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Contents

1. RASNZ 2009 Conference
2. The Solar System in June
3. June Fireballs?
4. Eyepieces for Spectacle Wearers
5. 'The Portal to the Universe' Opens
6. She Is An Astronomer
7. Anglo-Australian Telescope Funding Secure
8. Spitzer Space Telescope Warms to New Carrier
9. Lightest Exoplanet Yet Discovered
10. Cosmological Equivalence Principle
11. Most Distant Explosion So Far Seen
12. Mystery Blob in Early Universe
13. How to Join the RASNZ
14. Here and There

1. RASNZ 2009 Conference

Conference is but days away now. After a slow start, registrations picked up so, in spite of people understandable watching their pockets, numbers will be comparable to those of the last few years. It is still possible to register, however, except we may not be able to guarantee meals can be provided for late registrants.

The Registration Desk will be attended late Friday afternoon and up till the opening, and again prior to the commencement of the Saturday programme.

The Variable Star Symposium and Trans-Tasman Occultation Symposium have also attracted plenty of interest. Please note the Variable Star Colloquium gets underway at 10am on the Friday, and the Occultation Symposium at 9am on both days it is being held. Registration desks will be attended prior to the commencement of both.

The programme is full - and if you check the programme on the webpage you will see how exciting and interesting it is. The programme runs till 5pm on the Sunday. There are also several poster papers, and the winners of the RASNZ Photographic competition will also be on display.

Don't forget the Conference Dinner has a theme - please come dressed as your favourite astronomer. For those of you who are not able to bring attire, Marilyn tells us it is possible to hire it from the Costume Cave in Courtenay Place for a small fee. There has been a change in the Dinner programme - and Dr Ilana Feain from the CSIRO (Australia) will deliver an address on ASKAP.

The RASNZ Annual General Meeting is on in the final Saturday session - please bring your annual report (March Southern Stars), and the agenda etc that have been sent out by email to members.

The RASNZ wishes to acknowledge the support of the United States Embassy in enabling us to bring Dr Fulvio Melia to New Zealand as a Feature Speaker. And also the Australian High Commission for their sponsorship of our other Feature Speaker, Dr Chris Fluke.

Look forward to seeing you all in Wellington later this week - it's going to a great Conference, I'm sure. And thanks to the hard yards put in by the Local Organising Committee in Wellington.

Dennis Goodman, Chair, RASNZ Standing Conference Committee ----------------------

Conference speakers are, in order of appearance:

Saturday

Dr. Helen Anderson, CEO MORST, Conference opening.

Dr Tom Richards: Introducing Variable Stars South.
Alan Plummer and Mati Morel: The VSS RASNZ legacy and the evolving BV Centauri.
Dr Melanie Johnston-Hollitt: Understanding cluster dynamics with next generation
radio telescopes.
Glen Rowe: Tides and the real world.

Veronica Miller: A search for variable stars and transiting extrasolar planets in the

Galactic Plane.
Steve Butler: Activities of Dark Sky Section 2008/09.
Graeme Murray: New Zealand´s Starlight Observatory.
Steve Butler: Measuring up.
Dr. Chris Fluke: 3D Astronomy Visualisation: From Data to Documentary.
Dr Fluke's visit to New Zealand has been sponsored by the Australian High Commission.

Yvette Perrott: Parallax Effects in Gravitational Microlensing.

Professor Phil Yock: Gravitational Microlensing, New Zealand´s Contribution.
Dr Denis Sullivan: A Physical Description of Gravitational Microlensing Events.
Professor Fulvio Melia: Supermassive Black Holes.
Professor Melia's visit to New Zealand is supported by the US Embassy.

After Dinner Speaker: Dr Ilana Feain (CSIRO) Topic ASKAP

Sunday

David Herald: Video Astrometry.

Brian Loader: Lunar Occultations of Double Stars.
Owen Moore: Building an Amateur Observatory in your own home.
David MacLennan: Recent Revelations from Mars.
Bill Allen: Constructing the new GRB 0.6 m robotic telescope in Marlborough.

Dr Grant Christie: Science Objectives for the new BOOTES-3 Observatory.

Dimitri Douchin: Analysis of HST images of MOA microlensing event MB07379.
Graham Blow: Occultation Section Activities in 2008/09.
David Herald: Results of Asteroidal Occultations, 2007 and 2008.
Bob Evans: Aurora Section Activities 2008/09.
Gavin Milne: Education Section Activities 2008/09.

Jennie McCormick : "100 Hours of Astronomy"- Making History - A Global Astronomy.

Bob Evans: The next Aurora Season.
Gavin Milne: Secondary School Astronomy Education.
Rachel Soja: Dynamics of Resonant Meteoroids.
Professor Sergei Gulaev and Tim Natusch: The AUT Radio Telescope: current status and plans.
Dr Andrew Rakich: Status of the Large Binocular Telescope.

Poster Papers

Dr Edwin Budding et al: "Absolute Parameters of Young Stars: V831 Centauri".
Steve Butler, Poster: "Dark Skies".
Alan Plummer, Poster: "Visual Observation of Variable Stars".
Erik Vermaat, Poster: "Nga Whetu Resources; Supporting Astronomy Education"
Haritina Mogasanu: "Society for Maori Astronomy, Research and Tourism Trust dedicated to
astronomy education"

2. The Solar System in June

The usual notes on the visibility of the Planets for June 2009 have been placed on the RASNZ web site: http://www.rasnz.org.nz/SolarSys/Jun_09.htm. Notes for July 2009 will be in place in a few days.

The mid winter solstice is on June 21, with the Sun furthest north at 5:46 pm. The earliest sunset is a few days earlier in mid June, while the date of latest sunrise as at the end of the month.

The planets in june

The evening sky - saturn

Saturn will become an early evening object during June. It is at its highest at about 7pm at the start of the month, and nearly 2 hours earlier by the end. Thus the best time for viewing the planet will be the early evening once the sky has darkened. By the end of the month the planet will set before 11 pm.

During June the rings will start closing again as the Earth moves towards their plane. The planet remains in Leo with Regulus some 16 degrees away - to the lower left of Saturn early evening.

The 37% lit waxing Moon will be some 7.5 degrees above Saturn on the night of June 28. The previous night a thinner Moon will be rather further away to the left of the planet.

Saturn's brightest satellite Titan will be eclipsed by the planet twice during the month on June 8 and June 24. The first eclipse starts soon after sunset at 5:40 while the second starts before sunset. The eclipses end at 11:30 and 10:50 respectively, by which times the planet will be low in the sky making observation difficult.

There is also a transit of Titan's shadow across Saturn on June 16. The transit starts before sunset and ends at about 9:20pm.

All the inner Moons of Saturn are now being eclipsed. Reappearances from eclipse of Rhea, the second brightest satellite, occur on May 31 at 7:56pm, Jun 9 at 8:53pm and June 18 at 9:50. Saturn will be low by the time of the reappearance on June 18.

More details on observing these events and a table of the times of all the eclipses can be found on the page of eclipses of Titan and Rhea on the web site. Moderate sized telescopes are needed to see these events.

Jupiter, close to NEPTUNE, will be visible late evening and in the morning. It rises about 11 pm on June 1 and 2 hours earlier by the end of the Month. Fomalhaut, at magnitude 1.2 the brightest star in Piscis Austrinus, will be 20 degrees to the right of Jupiter and at about the same altitude.

Jupiter will remain in Capricornus throughout June. It is stationary on June 16, so will be slow moving all month. It passed close to Neptune at the end of May, and will be three-quarters of degree from it when stationary. After June 16 Jupiter will start moving back towards Neptune and the distance between the two will decrease again.

Neptune at magnitude 7.9 will be a rather faint object in binoculars, but should be detectable on a dark night. Late in the evening Neptune will be to the upper left of Jupiter and about half a degree below the 5th magnitude star mu Cap. There will be no other stars as bright as Neptune between the 3 objects. By the morning with the planets much higher, the sky will have rotated so that Neptune is to the lower left of Jupiter, with mu Cap to the left of Neptune and slightly higher.

On June 13 the waning Moon, 76% lit, joins Jupiter and Neptune. At midnight it will be some 3.5 degrees to the left of Jupiter. By the morning before sunrise, the Moon will have moved a little further from Jupiter and now appear below and to the right of the planet.

The morning sky - venus, mars and mercury

Venus will be the obvious brilliant object in the morning sky. At the beginning of June it will rise before 4am in most parts of New Zealand, a little after 4am in the south. That will be about half an hour before MARS. By the end of June, Venus will rise 35 minutes later, while Mars will continue to rise at the same time throughout June.

Venus starts June about 5 degrees above Mars. It passes the latter some three weeks later, with the two closest on the morning of June 22 when Venus will be just under 2 degrees to the right of Mars. They are only just over 2 degrees apart from June 20 to 24. On June 20 the crescent Moon will be just over 7 degrees below Mars.

The two planets end the month about 3.5 degrees apart with Mars to the left of, and a little higher than Venus. Mars, with a magnitude 1.1, will be more than 5 magnitudes fainter than Venus.

Mercury rises about 100 minutes before the Sun at the beginning of June and 2 hours before it mid June. By the end of June the planet will have moved back towards the Sun and be rising about 1 hour earlier. During the month the planet brightens from magnitude 2 to magnitude -0.9. As a result mid June is likely to be the best time for making a morning observation of the planet when it will have an altitude of about 10 degrees 50 minutes before sunrise.

Mercury will be in Taurus throughout June more than 20 degrees to the lower right of Venus. On the mornings of June 20 and 21 it will lie between the Pleiades and Aldebaran, considerably nearer the star than the cluster.

URANUS is in Pisces between Jupiter and Venus. On June 1 it will be about
midway between the two planets, 30 degrees from each.  While the distance
of Uranus from Jupiter stays about the same throughout June, its distance
from Venus and Mars will increase to 56 degrees by the end of the month.

Brighter asteroids:

(1) Ceres is an evening object setting about 11:30pm on June 1 and 10:30pm on June 30 with a magnitude ranging from 8.5 to 8.8. It is in Leo, its distance from Saturn decreasing from 11 degrees to 7 degrees during the month. It passes just under a quarter degree from the star theta Leo, magnitude 3.3, on June 20.

(2) Pallas starts June in Canis Minor 2.5 degrees from Procyon, and setting about 9 pm. Pallas moves into Hydra on June 12 and ends the month among the small group of 3rd and 4th magnitude stars, epsilon, rho and zeta Hya. Its magnitude is close to 9 throughout June.

(4) Vesta is in conjunction with the Sun on June 22, and is too close to it for observing throughout the month.

(7) Iris brightens to magnitude 8.9 by the end of June as it approaches opposition. It will then be in Sagittarius, 7 degrees from sigma Sgr, magnitude 2.1, and half that distance from pi Sgr, magnitude 2.9. Being near opposition it will be in the sky most of the night.

-- Brian Loader

3. June Fireballs?

Astronomers are encouraged to spend a few more minutes under the stars from the 1st-13th June this (and following) year.

Some New Zealand astronomers who are researching fireballs have discovered what could perhaps be a trend - more fireballs in early June than usual. This initial prediction is based on over 13 years of fireball reports by the NZ public and astronomers. The International Meteor Organisation (IMO) states that a meteor has to be brighter than magnitude -3 to be deemed a fireball.

The main direction to look - upwards naturally, but perhaps to the west as this is where the possible majority are seen. If you see any in the first two weeks of June (and at other times) contact RASNZ Comet and Meteor Section director John Drummond at This email address is being protected from spambots. You need JavaScript enabled to view it. . Fireball report forms (prepared by Jennie McCormick) are available from www.cometeor.co.nz

-- John Drummond

4. Eyepieces for Spectacle Wearers

The nzastropnomers group had an interesting discussion on eyepieces suitable for spectacle wearers. Also why some of us need to wear specs when observing.

The short answer from David Moorhouse was: The only reason to use glasses when observing is astigmatism. Being short or long sighted just requires a refocus. That said eyepieces like the Naglers and Panoptics are known for good eye relief. Try one out at the next Waharau star party or one close to you. (Eye relief is the distance the eye should be from the eyepiece lens to receive all the light from the eyepiece.)

As a general rule you will need 15-17 mm eye relief if you use glasses to observe, Most common Plossl eyepieces have about 0.8X their focal length in eye relief. So a 25 mm Plossl should have 20 mm eye relief and allow eyeglass use.

Kevin Barker provided more detail: As Dave pointed out astigmatism is the main reason why one would wear glasses. For near and long sighted folks focusing can allow sharp images.

Astigmatism however is another issue. We all have it to a smaller or greater degree. Astigmatism greatly reduces with smaller exit pupil diameter in the scope you are using.

To calculate the exit pupil diameter, divides the telescopes aperture by the magnification produces by the eyepiece. Magnification is given by focal length of telescope divided by eyepiece focal length. Example: Consider a 203 mm, f/6 scope with a 9 mm eyepiece. Magnification will be 203 X 6 divided by 9 = 135 X. Exit pupil will be 203/135 = 1.5 mm.

Astigmatism in a 2 mm or less exit pupil is going to be quite small. So wearing glasses may well not be necessary unless you suffer severe astigmatism.

Now with the same scope and a 25 mm Plossl, 203X6/25 = 49 X. Exit pupil is now 4.1 mm. So if you have significant astigmatism you can still wear glasses and see the full apparent field of view. If your astigmatism is low then no need for glasses.

Some of the more expensive higher quality eyepieces made by Tele-vue, Pentax, etc, have long eye relief for eyeglass users. Often at 3-4 times the cost of a basic plossl eyepiece.

5. 'The Portal to the Universe' Opens

The International Astronomical Union announces that a one-stop-shop astronomical information website has been set up. It is dubbed The Portal to the Universe. It opened for business on April 23, during the European Week of Astronomy and Space Science (JENAM 2009), at the University of Hertfordshire, UK.

The site features news, blogs, video podcasts, audio podcasts, images, videos and more. Web 2.0 collaborative tools, such as the ranking of different services according to popularity, help the user to sift constructively through the wealth of information available. It is hoped that it will promote interactions within the astronomy multimedia community. A range of "widgets" (small applications) have also been developed to tap into all sorts of existing live data, such as near-live pictures of the Sun, live positions of spacecraft or live observations from telescopes.

The Portal to the Universe can be accessed at http://www.portaltotheuniverse.org/

From an IAU press release forwarded by Karen Pollard. The full text of this press release is available on http://www.iau.org/public_press/news/release/iau0910/

6. She Is An Astronomer

The International Year of Astronomy 2009 Cornerstone project, She Is An Astronomer, was launched on April 21. She Is An Astronomer aims to help achieve several of the United Nations Millennium Development Goals, including promoting gender equality and empowering women.

Gender equality is a priority concern for the whole scientific community, regardless of its field, cultural background or geographic location. In astronomy only approximately one quarter of all professionals are women. In some countries there are no female astronomers, whilst in others more than half the professional astronomers are female. These numbers drop towards more senior levels, suggesting that scientific careers are heavily affected by social and cultural factors and are not determined solely by ability. She Is An Astronomer (SIAA), has been established to address these issues and tackle the main problems.

The SIAA program was announced during the European Week of Astronomy & Space Science at the University of Hertfordshire, UK. It is a mixture of international, national and local events ranging from conferences, meetings and workshops to address gender issues, events targeted at teenagers, and the central SIAA website, the variety is designed to appeal to a wide cross-section of the professional and public communities.

The official SIAA website, www.sheisanastronomer.org, provides a one-stop-shop for gender issues in astronomy and science. The site has five sections: profiles of living and historic astronomers; resources for female astronomers; events taking place during IYA2009; an SIAA Ambassadors¹ Area; and a forum where issues, lessons and challenges can be discussed, including the opportunity to question experts. The website provides neutral, informative and accessible information and will be used to advertise new events, keeping interested parties at the forefront of developments. Examples of best practices and relevant statistics will be pooled, making them accessible to the wider community. Content will be regularly added during 2009, resulting in a vast depository that will remain online long into the future, acting as an ongoing legacy.

Several of the international and national meetings arranged for 2009 feature a SIAA presence. These include the IAU General Assembly, meetings in the US and Egypt, a book launch in Australia, an exhibition in Germany and many local events. Spain is conducting its first ever survey of women in astronomy and has also produced a calendar featuring historic female astronomers.

IYA2009 encourages us to discuss magnificent and complex topics, from black holes to the mysteries of our Sun, but without losing sight of the core human aspects. SIAA will play its part in ensuring that the Year¹s impact is definitely felt here on Earth.

-- from an IAU press release forwarded by Karen Pollard.

7. Anglo-Australian Telescope Funding Secure

In a note to Astronomical Society of Australia members Professor Warrick Couch, Chairman of the Anglo-Australian Telescope Board announced:

I am delighted to relay to you that future funding for the Anglo- Australian Observatory (AAO) beyond the expiration of the current bi- national agreement (and hence total withdrawal by the UK) on 30 June next year, was announced in Tuesday night's Federal Budget. Moreover, we have been advised by the Department of Innovation, Industry, Science and Research (DIISR) that this funding has been secured for the next 10 years, through to 2018/19.

The specific funding details announced in the Budget are as follows: A total of $20.9M of new funding has been allocated for the next 4 years. In this period, total Australian Government funding for the AAO (excluding NCRIS and other grants) will be $36.5M. In fact, DIISR is forecasting that after the Australian Government takes sole ownership of the AAO on 1 July 2010, the AAO will have stable recurrent funding of about $11M p.a. through to 2018/19.

This commitment puts the AAO's financial future on a secure footing, so that it will be able to continue to provide users of the AAT with excellent instruments and high-quality service to the end of the decade, while maintaining its renowned instrumentation program in support of Australia's national and international optical telescope facilities. With AAO's funding secured, DIISR is now moving to resolve the future governance of the AAO.

On behalf of the AAT Board, I would like to acknowledge the extraordinary efforts and perseverance of the AAO's Director, Matthew Colless, and Executive Officer, Neville Legg, in securing this excellent funding outcome for the AAO. The Board also very much appreciates the patience and continued commitment and dedication of AAO staff through what has been a long and drawn-out period of uncertainty over the AAO's future.


Warrick Couch, originally from Lower Hutt, was recently elected a Fellow of the Australian Academy of Science. Warrick is also President of the Astronomical Society of Australia.

8. Spitzer Space Telescope Warms to New Career

The primary mission of NASA¹s Spitzer Space Telescope is about to end after more than five and a half years of probing the cosmos with its keen infrared eye. Within about a week of May 12, the telescope is expected to run out of the liquid helium needed to chill some of its instruments to operating temperatures.

The end of the coolant will begin a new era for Spitzer. The telescope will start its "warm" mission with two channels of one instrument still working at full capacity. Some of the science explored by a warm Spitzer will be the same, and some will be entirely new.

Spitzer is the last of NASA¹s Great Observatories, a suite of telescopes designed to see the visible and invisible colours of the universe. The suite also includes NASA¹s Hubble and Chandra space telescopes. Spitzer has explored, with unprecedented sensitivity, the infrared side of the cosmos, where dark, dusty and distant objects hide.

For a telescope to detect infrared light, heat, from cool cosmic objects, it must have very little heat of its own. During the past five years, liquid helium has kept Spitzer's three instruments chilled to -271 C, or less than 3 degrees above absolute zero. The coolant was planned to last as little as two and a half years, but Spitzer¹s efficient design and careful operations enabled it to last more than five and a half years.

Spitzer¹s new "warm" temperature is still quite chilly at -242 C. This temperature rise means two of Spitzer¹s instruments, the longer wavelength multiband imaging photometer and the infrared spectrograph, will no longer be cold enough to detect cool objects in space. However, the telescope¹s two shortest-wavelength detectors in its infrared array camera will continue to function perfectly. They will still pick up the glow from a range of objects: asteroids in our solar system, dusty stars, planet- forming disks, gas-giant planets and distant galaxies. In addition, Spitzer still will be able to see through the dust that permeates our galaxy and blocks visible-light views.

Since its launch in 2003, Spitzer has made countless breakthroughs in astronomy. Observations of comets both near and far have established that the stuff of comets and planets is similar throughout the galaxy. Breathtaking photos of dusty stellar nests have led to new insights into how stars are born. And Spitzer¹s eye on the very distant universe, billions of light-years away, has revealed hundreds of massive black holes lurking in the dark.

Perhaps the most revolutionary and surprising Spitzer finds involve planets around other stars, called exoplanets. Exoplanets are, in almost all cases, too close to their parent stars to be seen from our Earthly point of view. Nevertheless, planet hunters continue to uncover them by looking for changes in the parent stars. Before Spitzer, everything we knew about exoplanets came from indirect observations such as these.

In 2005, Spitzer detected the first actual photons from an exoplanet. In a clever technique, now referred to as the secondary-eclipse method, Spitzer was able to collect the light of a hot, gaseous exoplanet and learn about its temperature. Further detailed spectroscopic studies later revealed more about the atmospheres, or "weather" on similar planets. More recently, Spitzer witnessed changes in the weather on a wildly eccentric gas exoplanet -- a storm of colossal proportions brewing up in a matter of hours before quickly settling down.

Some of Spitzer¹s new pursuits include refining estimates of Hubble¹s constant, or the rate at which our universe is stretching apart; searching for galaxies at the edge of the universe; assessing how often potentially hazardous asteroids might impact Earth by measuring the sizes of asteroids; and characterizing the atmospheres of gas-giant planets expected to be discovered soon by NASA¹s Kepler mission. As was true during the cold Spitzer mission, these and the other programs are selected through a competition in which scientists from around the world are invited to participate.

For more information about Spitzer, visit: http://www.nasa.gov/spitzer http://www.spitzer.caltech.edu/spitzer

-- from a NASA press release forwarded by Karen Pollard.

9. Lightest Exoplanet Yet Discovered

The lightest exoplanet so far discovered, one only about twice the mass of our Earth, was announced on April 21st. The planet is the fourth discovered in the system around the star Gliese 581.

The planet, labelled Gliese 581 e orbits its host star in just 3.15 days. Being only 1.9 Earth-masses it is the least massive exoplanet ever detected and is, very likely, a rocky planet. Being so close to its host star, the planet is not in the habitable zone.

Gliese 581 is a low-mass red dwarf star located 20.5 light-years away in the constellation Libra. With the discovery of Gliese 581 e, its planetary system now has four known planets. The masses are about 1.9 (planet e), 16 (planet b), 5 (planet c), and 7 Earth-masses (planet d).

The planet furthest out, Gliese 581 d, orbits its host star in 66.8 days. Planet d is probably too massive to be made only of rocky material. It is suggested that it is an icy planet that has migrated closer to the star. If so then, since it is in the habitable zone, where liquid water could exist. 'd' could even be covered by a large and deep ocean making it the first serious 'water world' candidate.

The Gliese 581 planets have been found over the past two years by a large team using the HARPS spectrograph attached to the 3.6-metre ESO telescope at La Silla, Chile.

For more see http://www.eso.org/public/outreach/press-rel/pr-2009/pr-15-09.html

-- from a European Southern Observatory press release forwarded by Karen Pollard.

10. Cosmological Equivalence Principle

University of Canterbury cosmologist David Wiltshire's ideas continue to evolve as the following seminar abstract show:

Cosmological Equivalence Principle Through a series of thought experiments, I will tackle foundational questions which follow naturally from the questions Einstein asked when he first thought about the Equivalence Principle 100 years ago. I argue that Einstein overlooked an important aspect of the relativity of time in never quite realizing his quest to embody Mach's principle in his theory of gravity. As a step towards that goal, I broaden the Strong Equivalence Principle to a new principle of physics, the Cosmological Equivalence Principle, to account for the role of the evolving average regional density of the universe in the synchronization of clocks and the relative calibration of inertial frames. I apply the principle quantitatively to deduce the relative deceleration of observers in expanding regions of different density, which empirically accounts for the phenomenon we call "dark energy". This will be a conceptual talk, with some historical context; technical baggage will be kept to a minimum.

----- According the Einstein's equivalence principle all local, non- gravitational laws take the same mathematical form at the origin of a local inertial coordinate system. ----- For a MP3 download of David's interview on dark energy with National Radio's Kim Hill see http://www.radionz.co.nz/national/programmes/saturday/20080209/20080209

11. Most Distant Explosion So Far Seen

On 2009 April 23 NASA¹s Swift satellite discovered the most distant object so far observed in the universe: a spectacular stellar explosion known as a gamma-ray burst located about 13 billion light years away.

The satellite detected a ten-second-long gamma-ray burst of modest brightness. It quickly pointed its ultraviolet/optical and X-Ray telescopes at the burst location. Swift saw a fading X-ray afterglow but none in visible light.

That alone suggested this could be a very distant object. Beyond a certain distance, the expansion of the universe shifts all optical emission into longer infrared wavelengths. Ultraviolet light should be similarly shifted into the visible region. However, UV-absorbing hydrogen gas was denser at earlier times preventing any UV being red-shifted into optical wavelengths.

Ground-based imaging of the afterglow using the Gemini North Telescope on Mauna Kea showed the source in longer-wavelength images, but it was absent in an image taken at the shortest wavelength (1 micron). This "drop out" corresponded to a distance of about 13 billion light-years. By dissecting the infrared light of the afterglow into a spectrum, astronomers confirmed the burst¹s red-shift to be 8.2; the highest ever measured. This corresponds to a distance of 13.035 billion light-years.

The previous record holder was a burst seen in September 2008. It showed a red-shift of 6.7, which places it 190 million light-years closer than GRB 090423.

Gamma-ray bursts are the universe¹s most luminous explosions. Most occur when massive stars run out of nuclear fuel. As their cores collapse into a black hole or neutron star, gas jets - driven by processes not fully understood - punch through the star and blast into space. There, they strike gas previously shed by the star and heat it, which generates short- lived afterglows in other wavelengths.

For more see: http://www.cfa.harvard.edu/news/2009/pr200911_images.html

-- from a multi-institutional press release forwarded by Karen Pollard.

12. Mystery Blob in Early Universe

Using information from a suite of telescopes ground-based and satellite- borne, astronomers have discovered a mysterious, giant object that existed at a time when the universe was only about 800 million years old. Objects such as this one are dubbed extended Lyman-Alpha blobs; they are huge bodies of gas that may be precursors to galaxies. This blob was named Himiko for a legendary, mysterious Japanese queen. It stretches for 55 thousand light years, a record for that early point in time. That length is comparable to the radius of the Milky Way¹s disk.

The researchers are puzzled by the object. Even with superb data from the world¹s best telescopes, they are not sure what it is. Because it is one of the most distant objects ever found, its faintness does not allow the researchers to understand its physical origins. It could be ionized gas powered by a super-massive black hole; a primordial galaxy with large gas accretion; a collision of two large young galaxies; super wind from intensive star formation; or a single giant galaxy with a large mass of about 40 billion Suns. Because this mysterious and remarkable object was discovered early in the history of the universe in a Japanese Subaru field, the researchers named the object after the legendary mysterious queen in ancient Japan.

According to the Big Bang cosmology model, small objects form first and then merge to produce larger systems. This blob had a size of typical present-day galaxies when the age of the universe was about 800 million years old, only 6% of the age of today¹s universe.

Extended blobs discovered thus far have mostly been seen at a distance when the universe was 2 to 3 billion years old. No extended blobs have previously been found when the universe was younger. Himiko is located at a transition point in the evolution of the universe called the re-ionization epoch -- it¹s as far back as we can see to date. And at 55 thousand light years, Himiko is a big blob for that time.

This re-ionizing chapter in the universe was at the cosmic dawn, the epoch between about 200 million and one billion years after the Big Bang. During this period, neutral hydrogen began to form quasars, stars, and the first galaxies. Astronomers probe this era by searching for characteristic hydrogen signatures from the scattering of photons created by ionized gas clouds.

One of the puzzling things about Himiko is that it is so exceptional. If this was the discovery of a class of objects that are ancestors of today¹s galaxies, there should be many more smaller ones already found -- a continuous distribution. Because this object is, to this point, one-of-a-kind, it makes it very hard to fit it into the prevailing model of how normal galaxies were assembled. On the other hand, that¹s what makes it interesting!

The research is published in the May 10, 2009, issue of The Astrophysical Journal. An image of Himiko is at http://www.ciw.edu/http_www_ciw_edu_prouchihimikoimage4_6_09_jpg

-- from a press release forwarded by Karen Pollard

13. How to Join the RASNZ

A membership application form and details can be found on the RASNZ website http://www.rasnz.org.nz/InfoForm/membform.htm. Please note that the weblink to membership forms is case sensitive. Alternatively please send an email to the membership secretary This email address is being protected from spambots. You need JavaScript enabled to view it. for further information.

The annual subscription rate is $75. For overseas rates please check with the membership secretary, This email address is being protected from spambots. You need JavaScript enabled to view it..

14. Here and There

From The Observatory, v.129 p.108, April 2009.

ANTHROPIC PRINCIPLES IN THE MILKY WAY The 'Cosmic Diary' aims to put a human face on astronomy. -- IAU Information Bulletin 101, p.55.

THE LAST LAUGH Cosmic impacts teach lessons about science. -- Nature, v.453, contents page, 'Editorials'.

THE TRANSIENT NATURE OF CHARM AND BEAUTY A simulated Higgs bosom production and decay event. -- University of Cambridge 800 Years; 1209-2009 (Cambridge University Press), 2008, p.15.

CAREER ADVICE ...anyone who takes a university position will get no research support or time on telescopes,... --Annual Review of Astronomy and Astrophysics, v.45, 41, 2007.

Alan Gilmore Phone: 03 680 6000 P.O. Box 57 This email address is being protected from spambots. You need JavaScript enabled to view it. Lake Tekapo 7945 New Zealand


Newsletter editor:

Alan Gilmore   Phone: 03 680 6000
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