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I appologise for the inconvenience,

Peter Jaquiery (Web master)

First: thank you for registering on the RASNZ web site. For RASNZ members this is the first step toward gaining access to the RASNZ Members only area of the site. The next step is that the site administrators will notice your registration and add you to the Members group - as a RASNZ member you don't need to do anything more. This will usually happen within a day, but may occasionally take longer if our membership officer is not available. If the process is taking too long and you are anxious to get access to Southern Stars please This email address is being protected from spambots. You need JavaScript enabled to view it. who will get it sorted for you pending confirmation by the membership officer.

If you aren't yet a member of RASNZ we don't yet offer much "extra" on the site, although we are thinking about what we can provide for you. If you have ideas about what you would like to see please This email address is being protected from spambots. You need JavaScript enabled to view it. and we'll see what we can do for you. Otherwise you might consider joining the society. See Glen Rowe's article outlining the benefits of membership.

Anyway, have a fun, inspiring and educational time visiting our site and please let us know what you like or would like to see improved.

RASNZ Electronic Newsletter February 2018

The RASNZ Email newsletter is distributed by email on or near the 20th of each month. If you would like to be on the circulation list This email address is being protected from spambots. You need JavaScript enabled to view it. for a copy. The latest issue is below.

Email Newsletter Number 206

Affiliated Societies are welcome to reproduce any item in this email newsletter or on the RASNZ website http://www.rasnz.org.nz/ in their own newsletters provided an acknowledgement of the source is also included.

Contents

1. Stardate South Island - Quick Summary
2. RASNZ Administrative Deadlines
3. 2018 BHT Lectures - Expressions of Interest Sought
4. SWAPA Secondary School Competition
5. Waharau (Auckland) Star Party -- April 13-15
6. RASNZ Annual Conference
7. Call for Papers for 2018 RASNZ Conference
8. The Solar System in March
9. Variable Star News
10. Water Ice Found Exposed in Martian Cliffs
11. ESO's VLT Combo
12. HST's Little Blue Dots: Galaxies or Globular Clusters?
13. Extra Stars Downsize Some Exoplanets
14. How to Join the RASNZ
15. Kingdon-Tomlinson Fund
16. Quote

1. Stardate South Island - Quick Summary

Stardate South Island had a most successful weekend at Staveley, inland from Christchurch. Now a two-day event, both Friday and Saturday nights were clear, though Saturday's clouds were slow to go. Around 50 persons of all ages attended from Invercargill to Palmerston North. Many brought telescopes. Particular thanks go to 'camp mother' Jan Fortune and her helpers and Eaun Mason who arranged the speakers.

There was a good range of talks. Before dark on Friday Euan introduced the night sky and described star charts and apps for finding one's way around in it.

Hartina Mogasanu told of the NZ Astrobiology Network and its upcoming conference in Rotorua in June. See www.astrobiology.nz for details. Sam Leske described the Milky Way Kiwi Facebook page as a way to get astronomy out to the digital generation. Stardate photos are already on the site: see www.facebook.com/milkywaykiwi/ .

Graeme Kershaw detailed his work on restoring the Townsend telescope after it and its observatory were munted in the Christchurch earthquakes. Thanks to generous funding it will be known as the Townsend-Teece Telescope in future. Rebuilding the observatory tower will take longer than expected as deep foundation work is required.

The Soapbox segment was an opportunity for quick reports. The Canterbury Astronomical Society has Dr John Campbell talking about William Pickering, the New Zealander who directed NASA's Jet Propulsion Laboratory in the 1960s and 70s. SOFIA pilots will talk to CAS in June and July.

Peter Wilde and George Ionas, with a little help from their friends, have installed a new dome on the Palmerston North Astronomical Society's Observatory. Mike Broughton reported that access to the Dunedin Astronomical Society's (DAS) Beverley-Begg Observatory in Robin Hood Park has been improved. They meet on the first Tuesday each month. Three astronomy courses have attracted new members.

Ross Dickie noted that the Southland Museum have closed the attached observatory of the Southland Astronomical Society due to H&S concerns about its tall spiral staircase. However, a new location has been found in cooperation with the Scouts Association. A public star party attracted 400 persons to look through four telescopes. Ross later gave a quick account of the 1965 Matauri Bay total solar eclipse attended by his father Norman who died last year, aged 100.

Erik Vermat of Oxford has continued his work on the ngawhetu.nz website as an educational resource. See it at http://www.ngawhetu.nz/ . The Oxford group will celebrate Mars Week on Saturday 4 August. The main speaker will be Dr Jan Blank NASA Ames who is with the Mars Curiosity team. They need lots of telescopes. Ron Paine of Dunedin saw the total solar eclipse from Kentucky. Using an iOptron mount to track the sun he got an image every two minutes.

Carol McAlavey recalled the origin of Stardate SI in the early 1980s after a CAS member returned from the North Island original. Carol is now the last one still active of the committee that organised the first gathering. Carol noted that CAS is hosting the RASNZ Conference in Christchurch at the old University's Great Hall. The Rutherford Den is nearby.

Mike Broughton of the DAS circulated copies of papers from Nature on "The Dark Side of Night" and "Make Lighting Healthier". We, along with our fellow creatures, need the dark of the night for circadian rhythms and much else. Blue light in particular wakes us up. So the blue-rich (4000K) LED street lights favoured by Transit NZ are bad for us and bad for nature in general.

Euan Mason gave an introduction to telescopes: what to buy and what to avoid. There is a graph of telescope resolution and limiting magnitude in Sky & Telescope May 2004. Eyepieces are important too. Rob Glassey gave a tour of objects in the Small and Large Magellanic Clouds. There are good charts of the Clouds at http://www.cloudsofmagellan.net.au/ .

On Sunday morning Mike Broughton enlarged on the campaign against blue-rich LEDs. UNESCO has decreed that access to the night sky is a fundamental human right. Mike and other Dunedin persons, notably Kyra Xavier, have been encouraging the City Council to adopt sky-friendly lighting.

Further talks were going on when this scribe left for home. Perhaps other attendees might contribute summaries (and others from similar gatherings).

-- Ed.

2. RASNZ Administrative Deadlines

March 15 SWAPA applications deadline for high school students. See Item 4, below. March 31 - 2018 BHT Lectures - expressions of interest sought. Item 3. April 1 - submit titles and abstracts oral or poster papers. Item 7.

3. 2018 BHT Lectures - Expressions of Interest Sought

The Beatrice Hill-Tinsley (BHT) Lecture Trust seeks expressions of interest from affiliated societies for hosting the 2018 BHT lecturer, Professor Paul Groot. The tentative dates for the lectures are the first half of October. RASNZ affiliated societies wishing to host Professor Groot should send an expression of interest to the RASNZ Lecture Trust's secretary at This email address is being protected from spambots. You need JavaScript enabled to view it. before March 31 2018.

Paul Groot's lecture title and abstract:

"Dawn of gravitational wave astronomy The direct detection of gravitational waves by the LIGO and Virgo laser interferometers has opened a completely new field in astrophysics. The merger events of binary black holes and neutron stars have now been detected. The electromagnetic radiation from one event (GW170817) has also been detected in a world-wide effort by thousands of astronomers. After the current upgrades the LIGO/Virgo detectors will detect a gravitational wave signals at a likely rate of one per week. This amazing development also raises many questions and opens up new opportunities: How do these binary black holes form? Where and when were they formed? How do they link to massive stars? Are they really the production site of gold in the Universe. What is the highest and lowest mass black hole? What are neutron stars made up of? Can we find these events even without gravitational wave signals, by looking at short duration transients in the optical sky?

During the lecture I will give a short overview of the amazing results obtained sofar and look ahead to the new possibilities for understanding black holes, neutron stars and the violent Universe"

---------- Paul Groot is professor of astronomy at, and co-founder of, the Department of Astrophysics of Radboud University in Nijmegen, The Netherlands. His areas of expertise are ultracompact binaries, transient sources and gravitational wave emitters. The research is focused on discovering and characterizing these elusive systems and using them as a probe to understand fundamental physics. For details see https://www.astro.ru.nl/~pgroot/

4. SWAPA Secondary School Competition

The Royal Astronomical Society of New Zealand (RASNZ) is interested in promoting astronomy for NZ high school students who have an interest and passion for this science. The Society is holding its annual conference in 2018 in Christchurch from Friday 4th to Sunday 6th May. The normal conference registration for non-RASNZ members is around $200, however the Society is waiving this cost for up to 10 young astronomers who are keen to attend and find out more about our science. In addition, the cost of the Saturday night banquet, travel costs to/from the conference and accommodation (usually backpacker) for the Friday and Saturday nights are paid for. To be considered students should email a short statement of no more than 300 words explaining why they would like to attend the conference and why they are interested in astronomy. This statement should be sent to RASNZ President, John Drummond (email: This email address is being protected from spambots. You need JavaScript enabled to view it. by Thursday 15th March, 5 pm. Please include your name, school, age, year of study at school in 2018, email address, telephone contact and science teacher’s name.

The winners of the competition will be selected for a clear enthusiasm for astronomy, their seniority, and good English in their submitted statement. Alternatively, a printed version can be posted to John Drummond, PO Box 113, Patutahi 4045. The RASNZ Students with a Passion for Astronomy (SWAPA) competition is mostly intended for students in years 11, 12 or 13, however excellent students in years 10 or below should not be deterred from applying. Those who win the free registration/travel/accommodation will be notified around early-April 2018.

If possible, could RASNZ members print out this note and take it to local secondary schools in their area.

-- From "Keeping in Touch #25", 11 January 2018.

5. Waharau (Auckland) Star Party -- April 13-15

The Auckland Astronomical Society is holding a two-night Star Party at Waharau Regional Park again this year on April 13th to 15th. Last year over 70 people attended this event and got two clear nights.

For details, costs, etc, see https://www.astronomy.org.nz/new/public/eventcalendar.aspx

6. RASNZ Annual Conference

The annual RASNZ conference is less than four months away! It will be held in Christchurch from Friday 4th until Sunday 6th May 2018. These conferences are the highlight of academic astronomy in New Zealand and are always packed full of stimulating talks and enjoyable socialising. For more information go to the following webpage (note that it has yet to be updated from the 2017 info) - http://www.rasnz.org.nz/index.php/groupsnews-events/events/32-conference/444-conf-next . Immediately following the conference in Christchurch the Variable Star Symposium will run from Sunday 6th – Mon 7th May.

-- From "Keeping in Touch #25", 11 January 2018.

7. Call for Papers for 2018 RASNZ Conference

It is a pleasure to announce that the next conference of the Royal Astronomical Society of New Zealand (RASNZ) will be held in Christchurch over the weekend of 4th-6th May 2018. Our guest speaker will be Dr Katie Mack from the North Carolina State University, and the Fellows’ Lecture for 2018 will be delivered by Steve Butler. Titles and abstracts for these talks will be released when they are available.

The RASNZ standing conference committee (SCC) invites and encourages anyone interested in New Zealand Astronomy to submit oral or poster papers, with titles and abstracts due by 1st April 2018 or at such a time as the SCC deems the conference programme to be full. The link to the paper submission form can be found on the RASNZ Conference website www.rasnz.org.nz/Conference. Please note that you must be registered for the conference to give an oral presentation, and for your convenience a link has been provided if you wish to do this when you submit a paper.

Following the conference, the Variable Stars South Symposium (https://www.variablestarssouth.org/5th-variable-stars-south-symposium-christchurch-2018/) will be held at the YMCA Christchurch, 12 Hereford Street (close to the Conference venue), starting on the Sunday evening and continuing on Monday 7th May. Registration for the symposium is through the RASNZ Conference website (http://rasnz.org.nz/conference). It is not necessary to register for the conference if you only wish to attend the symposium. Paper submissions should be sent directly to the convenor Mark Blackford (This email address is being protected from spambots. You need JavaScript enabled to view it.).

We look forward to receiving your submissions and seeing you at the conference. Please feel free to forward this message to anyone who May find it of interest.

For further information on the RASNZ conference, registration details and associated events please visit the conference website at www.rasnz.org.nz/Conference

-- Warwick Kissling, RASNZ Standing Conference Committee

8. The Solar System in March

Dates and times shown are NZDT (UT + 13 hours) unless otherwise stated. Times are for Wellington. They will vary by a few minutes elsewhere in NZ. Data adapted from that shown by GUIDE 9

The Sun and Planets in March 2018, Rise & Set, Mag. & Cons.

      March  1         NZDT          March 31    NZDT  
      Mag  Cons    Rise    Set     Mag  Cons    Rise    Set   
SUN  -26.7  Aqr   6.59am  8.06pm  -26.7  Psc   7.32am  7.17pm
Merc  -1.3  Aqr   7.48am  8.32pm    5.6  Psc   7.57am  7.07pm
Venus -3.9  Aqr   7.59am  8.40pm   -3.9  Ari   8.12am  8.05pm
Mars   0.8  Aqr  12.29am  3.35pm    0.3  Sgr  11.43pm  2.54pm
Jup   -2.2  Lib  10.58pm  1.15pm   -2.4  Lib   8.59pm 11.14am
Sat    0.6  Sgr   1.44am  4.44pm    0.5  Sgr  11.53pm  2.52pm
Uran   5.9  Psc  10.51am  9.52pm    5.9  Psc   9.01am  7.58pm
Nep    8.0  Aqr   7.17am  8.17pm    8.0  Aqr   5.21am  6.18pm
Pluto 14.5  Sgr   2.45am  5.37pm   14.5  Sgr  12.50am  3.41pm
              March  1  NZDT              March 31  NZDT
Twilights    morning     evening        morning     evening
Civil:    start 6.33am, end 8.33pm   start 7.07am, end 7.42pm
Nautical: start 5.59am, end 9.06pm   start 6.35am, end 8.14pm
Astro:    start 5.24am, end 9.42pm   start 6.03am, end 8.47pm

The southern autumnal equinox is on March 21 at 5.16am NZDT

March Phases of the Moon, times NZDT (& UT)

  Full moon:     March  2 at  1.51pm (00:51 UT)
  Last quarter   March 10 at 12.20am (Mar  9, 11:20 UT)
  New moon:      March 18 at  2.12am (Mar 17, 13:12 UT)
  First quarter: March 25 at  4.35am (Mar 24, 15:35 UT)
  Full Moon:     April  1 at  1.37am (Mar 31, 12.37 UT)

MERCURY is an evening object through March but at best, mid month, it sets only half an hour after the Sun, so is always a difficult object. It reaches inferior conjunction on April 1

VENUS, also an evening object, is little easier then Mercury. For the first three weeks of March the two planets are quite close in the sky, it is only in the last few days that Venus pulls away from Mercury. By the end of the month Venus sets 48 minutes after the Sun, so will be very low after sunset.

MARS rise near midnight during March so is best seen in the morning sky. It moves away from Antares and closes in on Saturn during the month. The two planets are less than 2° apart on the 31st. The moon will be some 5° from Mars on the morning of the 10th.

JUPITER rises late evening at the beginning of March and mid evening by the end of the month. The moon will be 5° from Jupiter late evening on the 7th, two days before the planet is stationary.

SATURN is slow moving in Sagittarius with Mars closing in on it by the end of March. The ring system is wide open at present with Saturn's north pole tilted at an angle of over 25° towards the Earth.

URANUS is an early evening object in Pisces during March. By the end of the month it will be very close to Venus, but this means Uranus will set too soon after the Sun to observe.

NEPTUNE is at conjunction with the Sun on the 4th. At conjunction it will be less than 1° from the Sun, but nearly 30 AU, 4478 million km beyond it. After conjunction Neptune moves into the morning sky to rise more than two hours before the Sun on the 31st.

PLUTO, in Sagittarius at magnitude 14.5, is a morning object rising 6.5 hours earlier than the Sun by the end of the month. It will then be some 13° east of Saturn and 8° below the handle of the teapot as seen 90 minutes before sunrise.

Brightest Asteroids in March, magnitude, constellation, time of transit

March 1                March 31   
            Mag  Cons   transit    Mag  Cons   transit
(1) Ceres   7.4   Cnc   11.33pm    8.0   Cnc    9.31pm
(2) Pallas  9.1   Eri    6.14pm    9.1   Eri    5.05pm
(4) Vesta   7.5   Oph    8.00am    7.1   Sgr    6.43am

(1) CERES is slow moving in Cancer being stationary on March 20. It is best placed about mid evening. The moon is in Cancer on March 26 & 27 but about 15° south of Ceres.

(2) PALLAS is an evening object, magnitude 9.0 to 9.1. It sets about 1am on March 1 and 11.30 pm March 31. Mid month it will be 3° below gamma Eri, mag 2.9

(4) VESTA is essentially a morning object, rising about 1 am on the 1st and 11.30 pm on the 31st. It starts the month in Ophiuchus moving to the east on a path about 5° from that of Mars, although the latter moves ahead of the asteroid during March. Both cross into Sagittarius during March, Mars on the 11th, Vesta on the 19th.

-- Brian Loader

9. Variable Star News

Variable Stars with Close Companions. A number of variable stars have close companions which cause problems in photometry. AAVSO have a spreadsheet which catalogues these stars, listed in order of RA. It has recently been updated; check out the list on their web-site. A link is given in AAVSO Communication Feb 2018. The Variable star charts delivered by VSP note the presence of a companion.

Variable Stars South 2018 January issue of the VSS Newsletter is available and provides results of some of the collaborative programs operating in the section. There are reports on the campaign last year, photometric and spectrographic, on the triple star system V0454 Carinae, on V487 Vel, a DY Per star (pulsate like a red variable but also fade like R CrB stars) and on the yellow hypergiant V382 Carinae.

Stan Walker has an interesting analysis of the observations of Mira (omicron Ceti, the progenitor star of this class of variable) which has been observed for about 450 years. There is also a discussion of the VSS observing progam for Mira variables which in future will focus mostly on the longer period southern Mira, and introduce improvements in colour measurements. There is also an analysis of the eclipsing binary V871 Ara, giving an accurate epoch and refined period, and suggested classifications of the star types of the components.

To find the Newsletter VSS Home page https://www.variablestarssouth.org , hover over Newsletter image and Click on “Read More” which gives the Table of Contents. To download go to the image below the Table of Contents and left click.

C:\Users\AandH\Documents\astronomy\RASNZ 2017\RASNZ News 2018 Feb.doc

-- Alan Baldwin

10. Water Ice Found Exposed in Martian Cliffs

Thick sheets of water ice, some barely buried beneath the surface and likely more than 100 meters thick, have been spotted on several Martian cliff faces.

Geologists hoping to study the past climate history of Mars — and visionaries planning future visits by astronauts — got some great news with the discovery that exposures of water ice have been spotted on cliff faces.

The widely scattered outcrops, seven in the southern hemisphere and one in the north, lie at latitudes of 55° to 58° — far from the planet's polar caps of water (and carbon-dioxide) ice.

Colin Dundas (U.S. Geological Survey, Flagstaff) led the team that made the discovery using two instruments aboard NASA's Mars Reconnaissance Orbiter. First, detailed images from the spacecraft's HiRISE camera revealed banded layers in the scarps' steep faces that had a bluer colour than their surroundings. Then near-infrared maps from the CRISM spectrometer confirmed that the layers were strongly enriched in water ice.

It quickly became clear that the icy exposures were not merely seasonal coatings of frost but rather distinct layers of ice that persist year-round. They begin within a few meters of the surface and sometimes extend down to more than 100 m.

The team surmises that they started out as dusty snow or frost layers laid down over time that later compacted and recrystallized. The massive exposures are fresh because the scarps are actively eroding and retreating at a rate of a few millimetres each summer. Apparently the exposed ice gradually sublimates (changes directly from frozen to vapour), causing any embedded rocky material to crumble away and fall to the foot of each cliff face. What's left behind are constantly refreshed exposures of previously buried ice.

Planetary scientists have realized for more than a decade that vast deposits of water ice must lie just below the planet's dusty surface. For example, in 2008 the Phoenix lander found both ice-cemented soil and slabs of nearly pure ice covered by a thin veneer of rocky rubble. Radar scans from orbit have revealed that huge glaciers of ice lie within 20 metres of the surface — and likely are often much shallower — over roughly a third of the Martian surface.

Deposits of ice on Mars, laid down over millions of years, lie exposed in the planet's polar caps. But these new-found outcrops open an unprecedented window into Martian climatic and geologic history. "It's like having one of those ant farms where you can see through the glass on the side to learn about what's usually hidden beneath the ground," comments co-author Shane Byrne (University of Arizona) in a NASA press release.

Given the planet's thin atmosphere and temperature swings, geophysicists calculate that water ice on Mars at the scarps' locations should be stable at depths of as little as 10 cm. Being able to access water so easily would be a huge boon to future human exploration of the planet. Heck, imagine if "Martian" Mark Watney (a.k.a. Matt Damon) merely had to scrape a few inches into the ground to get all the water needed to sustain his potato crop!

The full study, "Exposed subsurface ice sheets in the Martian mid-latitudes," appears in the January 12th issue of Science.

-- See Kelly Beatty's original article with images at http://www.skyandtelescope.com/astronomy-news/cliffs-reveal-water-ice-on-mars/

11. ESO's VLT Combo

For the first time the light from the four 8.2-metre telescopes at the European Southern Observatory (ESO) has been combined. This makes it into the largest optical telescope in existence in terms of collecting area.

One of the original design goals of ESO's Very Large Telescope (VLT) was for its four Unit Telescopes (UTs) to work together to create a single giant telescope. With the first light of the ESPRESSO spectrograph using the four-Unit-Telescope mode of the VLT, this milestone has now been reached.

The light is combined incoherently. That means that the light from the four telescopes is simply added up, without the phase information being considered in the way that it is in the VLT Interferometer. The new incoherent combination of light has the light-collecting power of a 16-metre-aperture telescope but without its resolving power. The four telescopes have previously been used as an interferometer to image Antares. See last December's Newsletter, No. 204, Item 10.

Two of the main scientific goals of ESPRESSO are the discovery and characterisation of Earth-like planets and the search for possible variability of the fundamental constants of physics. The latter experiments in particular require the observation of distant and faint quasars, and this science goal will benefit the most from combining the light from all four Unit Telescopes in ESPRESSO. Both rely on the ultra-high stability of the instrument and an extremely stable reference light source.

A system of mirrors, prisms and lenses transmits the light from each VLT Unit Telescope to the ESPRESSO spectrograph up to 69 metres away. Thanks to these complex optics, ESPRESSO can either collect the light from up to all four Unit Telescopes together, increasing its light-gathering power, or alternatively receive light from any one of the Unit Telescopes independently, allowing for more flexible usage of observing time. ESPRESSO was specially developed to exploit this infrastructure.

Light from the four Unit Telescopes is routinely brought together in the VLT Interferometer for the study of extremely fine detail in comparatively bright objects. But interferometry, which combines the beams "coherently", cannot exploit the huge light-gathering potential of the combined telescopes to study faint objects.

For details see http://www.eso.org/public/unitedkingdom/news/eso1806/

-- From ESO press release eso1806 forwarded by Karen Pollard.

12. HST's Little Blue Dots: Galaxies or Globular Clusters?

The recent discovery of a new type of tiny, star-forming galaxy is the latest in a zoo of detections shedding light on our early universe. What can we learn from the unique “little blue dots” found in archival Hubble data?

As telescope capabilities improve and we develop increasingly deeper large-scale surveys of our universe, we continue to learn more about small, faraway galaxies. In recent years, increasing sensitivity first enabled the detection of “green peas” — luminous, compact, low-mass (<10 billion solar masses; compare this to the Milky Way’s ~1 trillion solar masses!) galaxies with high rates of star formation.

Not long thereafter, we discovered galaxies that form stars similarly rapidly, but are even smaller — only ~3–30 million solar masses, spanning less than ~3,000 light-years in size. These tiny powerhouses were termed “blueberries” for their distinctive colour.

Now, scientists Debra and Bruce Elmegreen (of Vassar College and IBM Research Division, respectively) report the discovery of galaxies that have even higher star formation rates and even lower masses: “little blue dots”.

The Elmegreens discovered these unique galaxies by exploring archival Hubble data. The Hubble Frontier Fields data consist of deep images of six distant galaxy clusters and the parallel fields next to them. It was in the archival data for two Frontier Field Parallels, those for clusters Abell 2744 and MAS J0416.1-2403, that the authors noticed several galaxies that stand out as tiny, bright, blue objects that are nearly point sources.

The authors performed a search through the two Frontier Field Parallels, discovering a total of 55 little blue dots with masses spanning 630,000 time the Sun's mass to 25 million with specific star formation rates of >10^-7.4, and redshifts of 0.5 < z < 5.4. (A specific star formation rate of 10^-7.4 means that stars form at a rate of 10^-7.4 stars per cubic parsec per year, I think. That's many stars per year in a galaxy's volume. -Ed.)

Exploring these little blue dots, the Elmegreens find that the galaxies’ sizes tend to be just a few hundred light-years across. They are gas-dominated; gas currently outweighs stars in these galaxies by perhaps a factor of five. Impressively, based on the incredibly high specific star formation rates observed in these little blue dots, they appear to have formed all of their stars in the last 1% of the age of the universe for them.

Intriguingly, this rapid star formation might be the key to answering a long-standing question: where do globular clusters come from? The Elmegreens propose that little blue dots might actually be an explanation for the origin of these orbiting, spherical, low-metallicity clusters of stars.

The authors demonstrate that, if the current star formation rates observed in little blue dots were to persist for another ~50 million years before feedback or gas exhaustion halted star production, the little blue dots could form enough stars to create clusters of roughly a million solar masses — which is large enough to explain the globular clusters we observe today.

If little blue dots indeed rapidly produced such star clusters in the past, the clusters could later be absorbed into the halos of today’s spiral and elliptical galaxies, appearing to us as the low-metallicity globular clusters that orbit large galaxies today.

Citation: Debra Meloy Elmegreen and Bruce G. Elmegreen 2017 ApJL 851 L44. doi:10.3847/2041-8213/aaa0ce

-- From the American Astronomical Society's 'Nova', repeated with images and graphics at http://www.skyandtelescope.com/astronomy-news/galaxies/ hubbles-view-of-little-blue-dots/

13. Extra Stars Downsize Some Exoplanets

Follow-up studies of candidates planetary systems found by NASA’s Kepler mission suggest that companion stars make some worlds appear smaller than they really are.

NASA’s Kepler mission gave astronomers a bountiful supply of homework. Checking up on the 4,000-plus candidate exoplanets that it turned up is a daunting task. Among those tackling the list is the Robo-AO team. Robo-AO is an automated laser-guided adaptive optics system, which when hooked up to a large telescope (most recently, the 2.1-meter on Kitt Peak) enables rapid-fire observations of a couple hundred stars each night.

The Robo-AO team has been checking each of Kepler’s candidate-planet-hosting stars to see if any other stars are lurking nearby. Nearby stars can muck up estimates of what the host star is really like (temperature, size) and even create signals that look like exoplanets but aren’t. It turns out that extra stellar companions can also make exoplanets look smaller than they really are. Carl Ziegler (University of North Carolina, Chapel Hill) reported that take-away as part of the big-picture results from the Robo-AO project on January 9th at the American Astronomical Society meeting in Washington, D.C.

Of 3,857 stars observed with Robo-AO, more than 600 had stellar companions. The light from this extra star can contaminate exoplanet detections with extra light, making their dips appear smaller and thus giving the impression that the planet candidates themselves are smaller than they really are. Broadly speaking, having another star in the system means planetary radii are roughly a factor of 2 larger than they appear. The team found that due to this contamination, 8 of the 26 potentially rocky, habitable-zone worlds studied might be gaseous. Among the candidates are the confirmed planets Kepler-438b and Kepler-437b. If these worlds orbit the primary star in the system, they’re still rocky, but if they instead orbit the secondary star, they’re 2 to 3 times larger than estimated and thus gaseous.

The team also sees indications that hot Jupiters are roughly four times more common in systems with more than one star than they are around single stars. Astronomers have previously suspected that a stellar companion could gravitationally mess with a gas giant enough to push it into a much smaller orbit around its star than it originally formed at. The Robo-AO results support that idea.

You can learn more about the project on the team’s website http://roboaokepler.org/

References: Carl Ziegler. “Robo-AO KOI Survey: LGS-AO imaging of every Kepler planetary candidate host car.” 231st AAS Meeting. Abstract 128.05.

Carl Ziegler et al. “Robo-AO Kepler Survey IV: The effect of nearby stars on 3857 planetary candidate systems.” arXiv.org. Posted December 12, 2017.

--See Camille M. Carlisle's original article at http://www.skyandtelescope.com/astronomy-news/extra-stars-might-downsize-exoplanets-2201201823/

14. How to Join the RASNZ

RASNZ membership is open to all individuals with an interest in astronomy in New Zealand. Information about the society and its objects can be found at http://rasnz.org.nz/rasnz/membership-benefits A membership form can be either obtained from This email address is being protected from spambots. You need JavaScript enabled to view it. or by completing the online application form found at http://rasnz.org.nz/rasnz/membership-application Basic membership for the 2017 year starts at $40 for an ordinary member, which includes an electronic subscription to our journal 'Southern Stars'.

15. Kingdon-Tomlinson Fund

The RASNZ is responsible for recommending to the trustees of the Kingdon Tomlinson Fund that grants be made for astronomical projects. The grants May be to any person or persons, or organisations, requiring funding for any projects or ventures that promote the progress of astronomy in New Zealand. Applications are now invited for grants from the Kingdon-Tomlinson Fund. The application should reach the Secretary by 1 May 2016. There will be a secondary round of applications later in the year. Full details are set down in the RASNZ By-Laws, Section J.

For an application form contact the RASNZ Executive Secretary, This email address is being protected from spambots. You need JavaScript enabled to view it. Nichola van der Aa, 32A Louvain Street, Whakatane 3120.

16. Quote

"There is nothing which can better deserve our patronage than the promotion of science and literature. Knowledge is in every country the surest basis of public happiness." -- George Washington, Address to Congress, January 8, 1790. Quoted on the Scientific American webpage.

Newsletter editor:

Alan Gilmore Phone: 03 680 6817
P.O. Box 57 Email: This email address is being protected from spambots. You need JavaScript enabled to view it.
Lake Tekapo 7945
New Zealand

Welcome to the Royal Astronomical Society of New Zealand website.

The RASNZ website provides astronomical information with a New Zealand and Southern Hemisphere focus for members of the RASNZ and for people interested in astronomy and astronomical events generally.

Registered RASNZ members have access to the online version of the Southern Stars (RASNZ journal) and other member specific information.

Hey! How did I get here?

Some of the pages from our old site (from before 2014) haven't made it across to this site. Please This email address is being protected from spambots. You need JavaScript enabled to view it. and let us know which page you were looking for so we can provide it for you.

Please Register

Please take the time to create an account, especially if you are a RASNZ member.  For RASNZ members this opens up a members only section of the website where you can download the latest Southern Stars journal. We also provide various RASNZ documents for member's use. If you think there is something missing that we should provide to members please This email address is being protected from spambots. You need JavaScript enabled to view it. and let us know!

If you are not a RASNZ member now would be a good time to sign up for membership. You can do this using the online membership application form found under the RASNZ heading.

If you belong to a society affiliated with RASNZ note it during registration and we will keep you informed of upcoming events by email as information comes to hand.

We are here to help

Please do tell us (by emailing the This email address is being protected from spambots. You need JavaScript enabled to view it.) about any issues or missing material you notice. We would also love to hear about ideas for content you may have.

Take some time to have a look around, and come back again soon as we develop and grow the site.

Clear Skies,
Peter J. & Simon L.

RASNZ Electronic Newsletter January 2018

The RASNZ Email newsletter is distributed by email on or near the 20th of each month. If you would like to be on the circulation list This email address is being protected from spambots. You need JavaScript enabled to view it. for a copy. The latest issue is below.

Email Newsletter Number 205

Affiliated Societies are welcome to reproduce any item in this email newsletter or on the RASNZ website http://www.rasnz.org.nz/ in their own newsletters provided an acknowledgement of the source is also included.

Contents

1. RASNZ Administrative Deadlines
2. Stardate South Island - February 16-19
3. 2018 BHT Lectures - Expressions of Interest Sought
4. SWAPA Secondary School Competition
5. Waharau (Auckland) Star Party -- April 13-15
6. RASNZ Annual Conference
7. Call for Papers for 2018 RASNZ Conference
8. The Solar System in February
9. News Flash: Nova Muscae 2018
10. Black Hole in Globular Cluster
11. Eight-Planet System Found By Kepler
12. Voyager 1 Fires Dormant Thrusters
13. Extremely Large Telescope's Mirrors Underway
14. Infant Stars Near Our Galaxy's Black Hole
15. How to Join the RASNZ
16. Gifford-Eiby Lecture Fund
17. Quotes

1. RASNZ Administrative Deadlines

February 3 is the deadline for the following: RASNZ Fellow nominations - RASNZ Rule 19 RASNZ Honorary Members nominations - RASNZ Rule 11 RASNZ Murray Geddes Prize nominations - RASNZ By-Law G5 Nominations of RASNZ Officers for 2018-20 - RASNZ Rule 74 Earth & Sky Bright Star Award - RASNZ By-Laws K

February 15 RASNZ Section and Group reports due to the Secretary - RASNZ By-Law F14 March 15 SWAPA applications deadline for high school students. See Item 4, below. March 31 - 2018 BHT Lectures - expressions of interest sought. Item 3. April 1 - submit titles and abstracts oral or poster papers. See Item 7.

2. Stardate South Island - February 16-19

Come and join us for a celebration of astronomy at Stardate SI. It all happens at Staveley, on the weekend of February 16th. This year's theme is "Getting started with your tour of the cosmos", and our special guest is Rob Glassey, who has some great talks and workshops to introduce you and your children to amateur astronomy.

Please register on-line at http://www.treesandstars.com/stardate/

-- Euan Mason.

3. 2018 BHT Lectures - Expressions of Interest Sought

The Beatrice Hill-Tinsley (BHT) Lecture Trust seeks expressions of interest from affiliated societies for hosting the 2018 BHT lecturer, Professor Paul Groot. The tentative dates for the lectures are the first half of October. RASNZ affiliated societies wishing to host Professor Groot should send an expression of interest to the RASNZ Lecture Trust's secretary at This email address is being protected from spambots. You need JavaScript enabled to view it. before March 31 2018.

Paul Groot's lecture title and abstract:

"Dawn of gravitational wave astronomy The direct detection of gravitational waves by the LIGO and Virgo laser interferometers has opened a completely new field in astrophysics. The merger events of binary black holes and neutron stars have now been detected. The electromagnetic radiation from one event (GW170817) has also been detected in a world-wide effort by thousands of astronomers. After the current upgrades the LIGO/Virgo detectors will detect a gravitational wave signals at a likely rate of one per week. This amazing development also raises many questions and opens up new opportunities: How do these binary black holes form? Where and when were they formed? How do they link to massive stars? Are they really the production site of gold in the Universe. What is the highest and lowest mass black hole? What are neutron stars made up of? Can we find these events even without gravitational wave signals, by looking at short duration transients in the optical sky?

During the lecture I will give a short overview of the amazing results obtained sofar and look ahead to the new possibilities for understanding black holes, neutron stars and the violent Universe"

---------- Paul Groot is professor of astronomy at, and co-founder of, the Department of Astrophysics of Radboud University in Nijmegen, The Netherlands. His areas of expertise are ultracompact binaries, transient sources and gravitational wave emitters. The research is focused on discovering and characterizing these elusive systems and using them as a probe to understand fundamental physics. For details see https://www.astro.ru.nl/~pgroot/

4. SWAPA Secondary School Competition

The Royal Astronomical Society of New Zealand (RASNZ) is interested in promoting astronomy for NZ high school students who have an interest and passion for this science. The Society is holding its annual conference in 2018 in Christchurch from Friday 4th to Sunday 6th May. The normal conference registration for non-RASNZ members is around $200, however the Society is waiving this cost for up to 10 young astronomers who are keen to attend and find out more about our science. In addition, the cost of the Saturday night banquet, travel costs to/from the conference and accommodation (usually backpacker) for the Friday and Saturday nights are paid for. To be considered students should email a short statement of no more than 300 words explaining why they would like to attend the conference and why they are interested in astronomy. This statement should be sent to RASNZ President, John Drummond (email: This email address is being protected from spambots. You need JavaScript enabled to view it. by Thursday 15th March, 5 pm. Please include your name, school, age, year of study at school in 2018, email address, telephone contact and science teacher's name.

The winners of the competition will be selected for a clear enthusiasm for astronomy, their seniority, and good English in their submitted statement. Alternatively, a printed version can be posted to John Drummond, PO Box 113, Patutahi 4045. The RASNZ Students with a Passion for Astronomy (SWAPA) competition is mostly intended for students in years 11, 12 or 13, however excellent students in years 10 or below should not be deterred from applying. Those who win the free registration/travel/accommodation will be notified around early-April 2018.

If possible, could RASNZ members print out this note and take it to local secondary schools in their area.

-- From "Keeping in Touch #25", 11 January 2018.

5. Waharau (Auckland) Star Party -- April 13-15

The Auckland Astronomical Society is holding a two-night Star Party at Waharau Regional Park again this year on April 13th to 15th. Last year over 70 people attended this event and got two clear nights.

6. RASNZ Annual Conference

The annual RASNZ conference is less than four months away! It will be held in Christchurch from Friday 4th until Sunday 6th May 2018. These conferences are the highlight of academic astronomy in New Zealand and are always packed full of stimulating talks and enjoyable socialising. For more information go to the following webpage (note that it has yet to be updated from the 2017 info) - http://www.rasnz.org.nz/index.php/groupsnews-events/events/32-conference/444-conf-next . Immediately following the conference in Christchurch the Variable Star Symposium will run from Sunday 6th - Mon 7th May.

-- From "Keeping in Touch #25", 11 January 2018.

7. Call for Papers for 2018 RASNZ Conference

It is a pleasure to announce that the next conference of the Royal Astronomical Society of New Zealand (RASNZ) will be held in Christchurch over the weekend of 4th-6th May 2018. Our guest speaker will be Dr Katie Mack from the North Carolina State University, and the Fellows' Lecture for 2018 will be delivered by Steve Butler. Titles and abstracts for these talks will be released when they are available.

The RASNZ standing conference committee (SCC) invites and encourages anyone interested in New Zealand Astronomy to submit oral or poster papers, with titles and abstracts due by 1st April 2018 or at such a time as the SCC deems the conference programme to be full. The link to the paper submission form can be found on the RASNZ Conference website www.rasnz.org.nz/Conference. Please note that you must be registered for the conference to give an oral presentation, and for your convenience a link has been provided if you wish to do this when you submit a paper.

Following the conference, the Variable Stars South Symposium will be held at the YMCA Christchurch, 12 Hereford Street (close to the Conference venue), starting on the Sunday evening and continuing on Monday 7th May. Details of the registration for the Symposium will be available with the registration form for the conference, and paper submissions should be sent directly to the convenor Mark Blackford (This email address is being protected from spambots. You need JavaScript enabled to view it.). Note that this Symposium will be held only if there is sufficient interest, so please register as soon as you can.

We look forward to receiving your submissions and seeing you at the conference. Please feel free to forward this message to anyone who May find it of interest.

For further information on the RASNZ conference, registration details and associated events please visit the conference website at www.rasnz.org.nz/Conference

-- Warwick Kissling, RASNZ Standing Conference Committee

8. The Solar System in February

Dates and times shown are NZDT (UT + 13 hours) unless otherwise stated.

Sunrise, Sunset and Twilight Times in February

Times are for Wellington. They will vary by a few minutes elsewhere in NZ.

             February  1  NZDT          February 28  NZDT
     SUN:  rise 6.23am, set 8.44pm    rise 6.57am, set 8.08pm
Twilights    morning     evening        morning     evening
Civil:    start 5.55am, end 9.13pm   start 6.32am, end 8.34pm
Nautical: start 5.17am, end 9.50pm   start 5.58am, end 9.08pm
Astro:    start 4.35am, end10.32pm   start 5.22am, end 9.43pm

February Phases of the Moon (times NZDT, as shown by GUIDE)

  Full moon:     February  1 at  2.27am (Jan 31, 13:27 UT)
  Last quarter   February  8 at  4.54am (Feb  7, 15:54 UT)
  New moon:      February 16 at 10.05am (Feb 15, 21:15 UT)
  First quarter: February 23 at  9.09pm (08:09 UT)

A total eclipse of the moon, fully visible from NZ, takes place on the night of January 31/February 1. The eclipse will be total between 1:51:25 am and 3:08:07 am on the morning of Feb 1. Further details can be found on the RASNZ web site.

The subsequent partial eclipse of the Sun on February 15/16 is visible from the Southern Ocean, well to the south of New Zealand, and the Antarctic continent. Its end will be visible from southern parts of Chile and Argentina

The Planets in February 2018

Mercury and Venus are too close to the Sun for observation all month. During February Jupiter and Saturn move up in the morning sky as does Mars to a lesser extent.

MERCURY starts February as a morning object, rising 1 hour before the Sun on the 1st. Half an hour before sunrise the planet will be only 4° above the horizon, its best for the month. Mercury reaches superior conjunction on the 17th, when it will be 207 million km from the Earth, 60 million beyond the Sun. After conjunction Mercury becomes an evening object but sets only 25 minutes after the Sun on the 28th.

VENUS, already in the evening sky, sets only 20 minutes after the Sun on the 1st, an interval increasing to 33 minutes by the end of February, 8 minutes after Mercury.

JUPITER, MARS and SATURN are early morning objects, with Mars between the two gas giants.

During the first few days of February, Mars will cross the narrow northern part of Scorpius before moving into Ophiuchus on the 8th. Three night later it will be at its closest to Antares when the two will be 5° apart. Mars rises at 1.20 am on February 1 and 12.30 am on the 28th.

Jupiter is the first of the three to rise, a little before 1 am at the beginning of the month, advancing to 11 pm by the end. The planet will be slow moving in Libra.

Saturn, the last to appear, rises just before 3.30 am on the 1st and 1.50 am on the 28th. It is in Sagittarius all month.

The moon, at last quarter, passes Jupiter on the morning of the 8th, Mars on the 9th and 10th and is 2.5° from Saturn on the 12th, by which date it will be a 15% lit crescent.

Outer Planets

URANUS is an evening object in Pisces during February. It is best placed in the sky as soon as it is dark, setting just before 10 am on the 28th at the end of the month.

NEPTUNE, magnitude 8.0, is an early evening object but will be lost in the twilight, especially at the end of February when it will set less than 15 minutes after the Sun.

PLUTO, in Sagittarius at magnitude 14.5, is a morning object rising 4 hours earlier than the Sun by the end of the month. It will then be some 13° east of Saturn and 8° below the handle of the teapot as seen 90 minutes before sunrise.

Brightest Minor Planets

(1) CERES is at opposition on February 4 when it will be in Cancer at magnitude 6.9. It will be in Cancer all month. With a declination over +30°, it will be low in NZ skies.

(2) PALLAS is an evening object, magnitude 9.0 to 9.1 during February. It will be in Eridanus.

(4) VESTA is a morning object in Ophiuchus with a magnitude ranging from 7.8 to 7.5. The asteroid will be moving to the east on a track parallel to and about 5° from, that of Mars. The latter overtakes Vesta on the 26th when the asteroid will be between eta Oph, magnitude 2.5 and Mars, magnitude 0.9. It will be just under 1.5° from the star and just over 5° from the planet.

(7) IRIS starts February in Aries but moves into Taurus on the 18th. During the month it fades from magnitude 9.2 to 9.7.

(8) FLORA is in Gemini all month, but fades from magnitude 9.2 to 10.0 during February.

-- Brian Loader

9. News Flash: Nova Muscae 2018

Rob Kaufman, Bright, Victoria, Australia, reported his discovery of an apparent nova (mag 7.0) on four CCD frames taken with a Canon 650D camera) on Jan. 14.486 UT; he provided an approximate position of R.A. = 11h26m12s.20, Decl. = -65d31'08".6 (equinox 2000.0). A low-resolution spectrogram shows strong hydrogen emissions as well as Fe II lines. The spectrum is viewable via website URL https://tinyurl.com/y6wkbnpz; the discovery image viewable via URL https://tinyurl.com/y8n5srrh). The spectrum suggests that this could be a classical "Fe II"-type nova.

The object has been given the provisional designation PNV J11261220-6531086. Follow up information is given in the discovery announcement CBET 4472: 2018 January 15.

-- Alan Baldwin

10. Black Hole in Globular Cluster

Astronomers have discovered a star in the globular cluster NGC 3201 that appears to be orbiting an invisible black hole with about four times the mass of the Sun. This is the first such inactive stellar-mass black hole found in a globular cluster and the first found by directly detecting its gravitational pull. This important discovery impacts on our understanding of the formation of these star clusters, black holes, and the origins of gravitational wave events.

Globular star clusters are huge spheres of stars. Most contain tens of thousands to millions of stars. Globular clusters orbit most galaxies. They are among the oldest known stellar systems in the Universe, dating back to near the beginning of galaxy growth and evolution. More than 150 are currently known to belong to the Milky Way.

Using the MUSE instrument on the European Southern Observatory's Very Large Telescope in Chile measured the radial velocities - line-of-sight velocities - of thousands of stars in the globular cluster NGC 3201.

One of the stars in NGC 3201 was found to be orbiting something completely invisible over 167 days at a speed of several hundred thousand kilometres per hour. This showed that the invisible object had a mass around 4.36 times the Sun's mass, almost certainly a black hole. This was the first one found in a globular cluster by directly observing its gravitational pull. The only other plausible dark object would be an improbably massive neutron star binary.

The relationship between black holes and globular clusters is an important but mysterious one. Because of their large masses and great ages, these clusters are thought to have produced a large number of stellar-mass black holes - created as massive stars within them exploded and collapsed over the long lifetime of the cluster. However, interaction at the cluster's core are thought to eject black holes from the cluster relatively quickly.

Recent detections of radio and X-ray sources in globular clusters, as well as the 2016 detection of gravitational-wave signals produced by the merging of two stellar-mass black holes, suggest that these relatively small black holes May be more common in globular clusters than previously thought.

-- From ESO press release eso1802, forwarded by Karen Pollard. See the original at https://www.eso.org/public/unitedkingdom/news/eso1802/

11. Eight-Planet System Found By Kepler

Our solar system now is tied for most number of planets around a single star, with the recent discovery of an eighth planet circling Kepler-90, a Sun-like star 2,545 light-years from Earth. The planet was discovered in data from NASA's Kepler Space Telescope.

The newly-discovered Kepler-90i -- a sizzling hot, rocky planet that orbits its star once every 14.4 days -- was found using machine learning from Google. Machine learning is an approach to artificial intelligence in which computers 'learn'. In this case, computers learned to identify planets by finding in Kepler data instances where the telescope recorded signals from planets beyond our solar system, known as exoplanets.

The discovery came about after researchers Christopher Shallue and Andrew Vanderburg trained a computer to learn how to identify exoplanets in the light readings recorded by Kepler -- the miniscule change in brightness captured when a planet passed in front of, or transited, a star. Inspired by the way neurons connect in the human brain, this artificial 'neural network' sifted through Kepler data and found weak transit signals from a previously-missed eighth planet orbiting Kepler-90, in the constellation Draco.

Other planetary systems probably hold more promise for life than Kepler-90. About 30 percent larger than Earth, Kepler-90i is so close to its star that its average surface temperature is believed to exceed 400 C, on par with Mercury. Its outermost planet, Kepler-90h, orbits at a similar distance to its star as Earth does to the Sun. The planetary system is like a mini version of our solar system: small planets orbit inside and big planets outside, but everything is scrunched in much closer.

Kepler's four-year dataset consists of 35,000 possible planetary signals. Automated tests, and sometimes human eyes, are used to verify the most promising signals in the data. However, the weakest signals often are missed using these methods. Shallue and Vanderburg thought there could be more interesting exoplanet discoveries faintly lurking in the data.

Kepler-90i wasn't the only jewel this neural network sifted out. In the Kepler-80 system, they found a sixth planet. This one, the Earth-sized Kepler-80g, and four of its neighbouring planets form what is called a resonant chain -- where planets are locked by their mutual gravity in a rhythmic orbital dance. The result is an extremely stable system, similar to the seven planets in the TRAPPIST-1 system.

-- From a NASA press release forwarded by Karen Pollard. See more at https://www.jpl.nasa.gov/news/news.php?release=2017-321https://www.nasa.gov/press-release/artificial-intelligence-nasa-data-used-to-discover-eighth-planet-circling-distant-star

12. Voyager 1 Fires Dormant Thrusters

After 37 years unused, the spacecraft Voyager 1 test-fired its four backup Trajectory Course Manoeuvring thrusters on November 28th. The thrusters fired in short, 10-millisecond bursts. The signal that the spacecraft had performed the manoeuvre, which had to travel for 19 hours and 35 minutes back to Earth, successfully arrived at the Deep Space Network in Goldstone, California, on November 29th.

'With these thrusters that are still functional after 37 years without use, we will be able to extend the life of the Voyager 1 spacecraft by two to three years,' says Suzanne Dodd (NASA-JPL) in a recent press release.

Voyager 1 periodically uses its main attitude control thrusters to keep its communications antenna aimed at Earth. However, engineers have noticed that the aging thrusters had degraded since 2014, requiring longer burns to generate the same amount of energy. So they came up with a solution: use the long dormant Trajectory Course Manoeuvring (TCM) thrusters for attitude control.

Identical in size and shape to the main attitude-control thrusters, the four TCM thrusters are located on the back of the spacecraft. Built by Aerojet Rocketdyne, they were used during the hectic Jupiter and Saturn encounters to ensure that the spacecraft's instruments pointed at the two gas giants and their respective moons. The final use of the TCMs came on 8 November 1980, leading up to the planned Titan encounter four days later, a trade-off manoeuvre that also ejected Voyager 1 out of the plane of the solar system.

Those early burns used the TCM thrusters in a continuous firing mode. Voyager 1 had never used them in short bursts for spacecraft orientation. The new plan sent engineers digging back through old Voyager data and software, much of which was coded in an assembler programming language as old as the thrusters themselves.

The test firing was a success. Engineers now plan to start using the TCM thrusters for primary spacecraft orientation control in January 2018, and they might instruct Voyager 2 to do the same. According to Enrique Medina (NASA-JPL), Voyagers 1 and 2 have 14 and 23 kilograms of hydrazine propellant remaining, respectively.

The plan is not, however, without its drawbacks. The thrusters need heat to operate, and turning on extra spacecraft heaters, one for each thruster, draws energy from the power supply, a plutonium-238-fueled Radioisotope Thermoelectric Generator. The half-life of plutonium-238 is 88 years, and the mission has just reached its 40th-year anniversary. Still, when there is no longer extra power to heat the TCM thrusters, the team plans to switch back to the main thrusters for future adjustments.

Voyager 1 was actually launched two weeks after Voyager 2, on 5 September 1977. It's currently the most distant human spacecraft ever fielded, more than 141 times the Earth-Sun distance (astronomical units, or a.u.) from the Sun and counting. The spacecraft is flying away from our solar system at 17 km per second in the direction of the constellation Ophiuchus. It crossed the boundary into interstellar space in August 2012, as reckoned by the sudden decrease of solar-wind particles and a corresponding increase in cosmic-ray particles. The abrupt change marked the spacecraft's crossing of the heliopause, the bubble carved out by the solar wind.

Voyagers 1 and 2 are two of five spacecraft on an escape trajectory out of the solar system ? Pioneers 10 and 11 and New Horizons are also on their way out.

Fun fact: The first recently discovered rock from interstellar space, 1I/2017 U1 'Oumuamua, will overtake all of these spacecraft as it, too, leaves the solar system. It'll pass Voyager 1 in 2083, although unlike Voyager 1, 'Oumuamua is moving in the direction of the constellation Pegasus.

-- From David Dickinson's article on Sky & Telescope's webpage at http://www.skyandtelescope.com/astronomy-news/voyager-1-fires-dormant-thrusters-in-deep-space/

13. Extremely Large Telescope's Mirrors Underway

The first six hexagonal segments for the main mirror of the European Southern Observatory's (ESO's) Extremely Large Telescope (ELT) have been successfully cast by the German company Schott at their facility in Mainz. These segments will form parts of the ELT's 39-metre main mirror, which will have 798 segments in total when completed. The ELT will be the largest optical telescope in the world when it sees first light in 2024.

The 39-metre-diameter primary mirror of ESO's Extremely Large Telescope will be by far the largest ever made for an optical-infrared telescope. Such a giant is much too large to be made from a single piece of glass, so it will consist of 798 individual hexagonal segments, each measuring 1.4 metres across and about 5 centimetres thick. The segments will work together as a single huge mirror to collect tens of millions of times as much light as the human eye.

As with the telescope's secondary mirror blank, the ELT main mirror segments are made from the low-expansion ceramic material Zerodur from Schott. ESO has awarded this German company with contracts to manufacture the blanks of the first four ELT mirrors, known as M1 to M4, with M1 being the primary mirror.

The first segment castings are important as they allow the engineers at Schott to validate and optimise the manufacturing process and the associated tools and procedures.

The casting of the first six segments is a major milestone, but the road ahead is long - in total more than 900 segments will need to be cast and polished (798 for the main mirror itself, plus a spare set of 133). When fully up to speed, the production rate will be about one segment per day.

After casting, the mirror segment blanks will go through a slow cooling and heat treatment sequence and will then be ground to the right shape and polished to a precision of 15 nanometres across the entire optical surface. The shaping and polishing will be performed by the French company Safran Reosc, which will also be responsible for additional testing.

For background see https://www.eso.org/public/unitedkingdom/news/eso1801/ For telescope design details see https://www.eso.org/public/unitedkingdom/news/eso1704/ For the mirror production contract see https://www.eso.org/public/unitedkingdom/news/eso1717/

-- From ESO press release eso1801 forwarded by Karen Pollard.

14. Infant Stars Near Our Galaxy's Black Hole

At the centre of our galaxy, in the immediate vicinity of its supermassive black hole, is a region wracked by powerful tidal forces and bathed in intense ultraviolet light and X-ray radiation. These harsh conditions, astronomers surmise, do not favour star formation, especially low-mass stars like our sun. Surprisingly, new observations from the Atacama Large Millimeter/submillimeter Array (ALMA) suggest otherwise.

ALMA has revealed the tell-tale signs of eleven low-mass stars forming perilously close - within three light-years - to the Milky Way's supermassive black hole, known to astronomers as Sagittarius A* (Sgr A*). At this distance, tidal forces driven by the supermassive black hole should be energetic enough to rip apart clouds of dust and gas before they can form stars.

The presence of these newly discovered protostars (the formative stage between a dense cloud of gas and a young, shining star) suggests that the conditions necessary to birth low-mass stars May exist even in one of the most turbulent regions of our galaxy and possibly in similar locales throughout the universe.

'Despite all odds, we see the best evidence yet that low-mass stars are forming startlingly close to the supermassive black hole at the centre of the Milky Way,' said Farhad Yusef-Zadeh, an astronomer at Northwestern University in Evanston, Illinois, and lead author on the paper. 'This is a genuinely surprising result and one that demonstrates just how robust star formation can be, even in the most unlikely of places.'

The ALMA data also suggest that these protostars are about 6,000 years old. 'This is important because it is the earliest phase of star formation we have found in this highly hostile environment,' Yusef-Zadeh said.

The team of researchers identified these protostars by seeing the classic 'double lobes' of material that bracket each of them. These cosmic hourglass-like shapes signal the early stages of star formation. Molecules, like carbon monoxide (CO), in these lobes glow brightly in millimeter-wavelength light, which ALMA can observe with remarkable precision and sensitivity.

Protostars form from interstellar clouds of dust and gas. Dense pockets of material in these clouds collapse under their own gravity and grow by accumulating more and more star-forming gas from their parent clouds. A portion of this infalling material, however, never makes it onto the surface of the star. Instead, it is ejected as a pair of high-velocity jets from the protostar's north and south poles. Extremely turbulent environments can disrupt the normal procession of material onto a protostar, while intense radiation - from massive nearby stars and supermassive black holes - can blast away the parent cloud, thwarting the formation of all but the most massive of stars.

The Milky Way's galactic center, with its 4 million solar mass black hole, is located approximately 26,000 light-years from Earth in the direction of the constellation Sagittarius. Vast stores of interstellar dust obscure this region, hiding it from optical telescopes. Radio waves, including the millimeter and submillimeter light that ALMA sees, are able to penetrate this dust, giving radio astronomers a clearer picture of the dynamics and content of this hostile environment.

Prior ALMA observations of the region surrounding Sgr A* by Yusef-Zadeh and his team revealed multiple massive infant stars that are estimated to be about 6 million years old. These objects, known as proplyds, are common features in more placid star-forming regions, like the Orion Nebula. Though the galactic center is a challenging environment for star formation, it is possible for particularly dense cores of hydrogen gas to cross the necessary threshold and forge new stars.

The new ALMA observations, however, revealed something even more remarkable, signs that eleven low-mass protostars are forming within 1 parsec - a scant 3 light-years - of the galaxy's central black hole. Yusef-Zadeh and his team used ALMA to confirm that the masses and momentum transfer rates - the ability of the protostar jets to plow through surrounding interstellar material - are consistent with young protostars found throughout the disk of our galaxy.

---------- Reference: F. Yusef-Zadeh et al. 'ALMA Detection of Bipolar Outflows: Evidence for Low-mass Star Formation within 1 pc of Sgr A*.' Astrophysical Journal Letters. December 1, 2017. Full text here: https://arxiv.org/abs/1711.10573

See also Camille M. Carlisle's article at http://www.skyandtelescope.com/astronomy-news/infant-stars-huddle-near-black-hole-412201723/

15. How to Join the RASNZ

RASNZ membership is open to all individuals with an interest in astronomy in New Zealand. Information about the society and its objects can be found at http://rasnz.org.nz/rasnz/membership-benefits A membership form can be either obtained from This email address is being protected from spambots. You need JavaScript enabled to view it. or by completing the online application form found at http://rasnz.org.nz/rasnz/membership-application Basic membership for the 2017 year starts at $40 for an ordinary member, which includes an electronic subscription to our journal 'Southern Stars'.

16. Gifford-Eiby Lecture Fund

The RASNZ administers the Gifford-Eiby Memorial Lectureship Fund to assist Affiliated Societies with travel costs of getting a lecturer or instructor to their meetings. Details are in RASNZ By-Laws Section H.

For an application form contact the Executive Secretary This email address is being protected from spambots. You need JavaScript enabled to view it., Nichola van der Aa, 32A Louvain Street, Whakatane 3120.

17. Quotes

"Everything happens for a reason. Sometimes the reason is you're stupid and make bad decisions." -- Roadside sign passed along by Lynne Frost.

"There's a special place in he'll for autocorrect". -- Bill Murray quoted in The NZ Listener's 'Funniest Quotes' book, as are those below.

"Stop anthromorphising inanimate objects. They don't like it." -- Twitter.

"My grandfather invented social media. Well, when I say social media, he invented the concept of telling everyone what he was doing whether they wanted to know or not." -- British Comedian John Bishop.

"Economists are concerned that a quarter of over fifties are failing to save. It's 'Control S', you silly old duffers!" -- Jimmy Carr.

"The majority of Year 8 students (41%) are achieving below expectations in mathematics. -- Bay of Plenty Times.

"Superannuitants with SuperGold concession cards are being urged by the Ministry of Social Development to check they have not expired." -- Dominion Post.

Newsletter editor:

Alan Gilmore Phone: 03 680 6817
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Lake Tekapo 7945
New Zealand