Solar System notes for March, 2017
The Solar System In March 2017
Dates and times shown are NZDT (UT + 13 hours).
Sunrise, sunset and twilight times in March
Times are for Wellington. They will vary by a few minutes elsewhere in NZ.
March 1 NZDT March 31 NZDT morning evening morning evening SUN: rise: 6.59am, set: 8.06pm rise: 7.32am, set: 7.16pm
Twilights Civil: starts: 6.33am, ends: 8.32pm starts: 7.07am, ends: 7.42pm Nautical: starts: 6.00am, ends: 9.06pm starts: 6.35am, ends: 8.14pm Astro: starts: 5.24am, ends: 9.41pm starts: 6.03am, ends: 8.46pm
The southern autumnal equinox is on March 20 at 11:29 pm
March phases of the moon (times as shown by guide)
First quarter: March 6 at 12.32 am (Mar 5, 11:32 UT) Full moon: March 13 at 3.54 am (Mar 12, 14:54 UT) Last quarter March 21 at 4.58 am (Mar 20, 15:58 UT) New moon: March 28 at 3.57 pm (02:57 UT)
The planets in March 2017
Mercury, Venus and Neptune are all at conjunction with the Sun during March so will be too close to the Sun for observation much of the month. Mars will remain an early evening object rather low to the west at sunset. Jupiter will move up into the evening sky being a few days short of opposition at the end of the month. Saturn is mostly a morning object but will rise shortly before midnight by the end of March.
Mercury is virtually unobservable throughout March. It is at superior conjunction on the far side of the Sun at midday on the 7th, NZ time. At conjunction the planet will pass 1.5° south of the Sun as seen from the Earth. Mercury will then be 204 million km ( 1.36 AU) from the Earth placing it 55.8 million km beyond the Sun
Before conjunction it is a morning object, but rises only 30 minutes before the Sun on the 1st. After conjunction Mercury becomes an evening object, but even by the 31st it will set only 30 minutes after the Sun.
Evening planets, venus, mars and jupiter
Venus sets some 40 minutes after the Sun on March 1. It is a very low object, only 4° up, 15 minutes after sunset, 30° north of the position of the set Sun. The comet Encke at magnitude 5.2 will then be 9° to the left of Venus and slightly lower but too faint to observe.
The angular distance of Venus from the Sun steadily decreases during the month until the planet is at inferior conjunction late on the evening of March 25. At conjunction the planet will pass 8° north of the Sun as seen from the Earth. It will be 42 million km from us and 108 million from the Sun.
After conjunction Venus will move into the morning sky and rise about 35 minutes before the Sun on the 31st but will be too low for observation.
Mars will also be a low early evening object. On the 1st it will be about 10° up 40 minutes after sunset, at the time Venus sets. Mars will be a little to the right of the position of Venus. Uranus will be less than 2° to the left of Mars but at magnitude 5.9 a difficult binocular object in the twilit sky.
Mars manages to keep ahead of the Sun during March, it sets 100 minutes after the Sun on the 1st and 85 minutes after on the 31st. The magnitude of Mars dims from 1.3 to 1.5 during the month.
On the evening of March 2 the 16% lit crescent moon will be just over 6° from Mars, above and to the right of the planet. A rather similar meeting of Mars and the moon will occur on the 31st, with the moon then 13% lit.
Jupiter will be the planet of the evening sky during March, although on the 1st it will not rise until 90 minutes after the Sun sets. By the end of March it will be up only 16 minutes after the Sun goes down.
On the 1st it will be 10.30 pm before Jupiter is reasonably easy to see 9° up to the east with Spica 4° to the upper right of the planet. The two form a pair throughout March, by the 31st they will be 6° apart.
On the 14th, two days after full moon, the latter will be 6.5° to the left of Jupiter as seen late evening, by the following morning the two will just over 4° apart. The rotation of the sky will bring the moon below Jupiter with Spica above the planet. The three should make an interesting grouping throughout the night.
Saturn in the morning sky.
Saturn rises an hour after midnight on the 1st and close to 11 pm on the 31st. Thus it remains essentially a morning sky object. The planet is in Sagittarius but some distance from the brighter stars of the constellation.
The last quarter moon will be just over 4° from Saturn on the morning of 21st NZ time.
Uranus, at magnitude 5.9, remains in Pisces throughout the month setting 95 minutes after the Sun on the 1st, but only 30 minutes later on the 31st. It starts the month a couple of degrees to the left of Mars, but the latter moves steadily away from Uranus during the month. Also on the 1st the 9% lit crescent moon will be 7° to the left of Uranus with Mars 2° on the opposite side of Uranus, the three forming an almost horizontal line. The following evening the moon will be to the upper right of Mars.
Neptune is another planet at conjunction with the Sun in March, on the 2nd. After conjunction it will become a morning object, rising nearly 2.5 hours before the Sun on the 31st. The planet at magnitude 8.0 remains in Aquarius throughout March.
Pluto is in the morning sky rising about 2.35 am on the 1st and 12.40 am on the 31st. It will remain in Sagittarius about 2.5° from the 2.9 mag star pi Sgr.
(1) Ceres is an early evening object, magnitude 9.1. It starts the month in Cetus but moves into Aries starting on the 3rd. By the 31st it will set about 9 pm and be 4.5° to the upper right of Mars with the crescent moon 5.5° to the upper right of Ceres, the three not quite in line.
(4) Vesta an evening object in March will have a magnitude rising from 7.2 to 7.6 during the month. It is stationary early in the month and will then move slowly to the east. The asteroid is in Gemini and will be only 2.4° from beta Gem, Pollux, magnitude 1.2 by the end of March.
A loose cluster of asteroids are bright enough to be seen in binoculars at the beginning of March. On the 1st they are probably best seen about 11pm when they will be between NNE and NE. The asteroids are (9) METIS, (14) IRENE and (29) AMPHITRITE in Leo and (15) EUNOMIA in Sextans. Irene, magnitude 9.1, is just under 7° to the lower left of Metis, 9.2, while Amphitrite, 9.2, is some 14° to the upper right of Metis. Eunomia, mag 9.4,is further away, 21° above Metis. Regulus, the brightest star in Leo, is near midway between Eunomia and Metis, a little closer to the latter. At 11 pm the star will be about 30° above the horizon.
All four asteroids fade during the month and are likely to be lost to binocular view by the 31st.
COMET P/Encke (2P) is in Pisces fairly close to Venus with a magnitude 5.5 on the 1st. But it will be too low in southern skies following sunset to observe.
Brian Loader New Zealand
Solar System notes for February, 2017
The Solar System In February 2017
Dates and times shown are NZDT (UT + 13 hours).
Rise and set times are for Wellington. They will vary by a few minutes elsewhere in NZ.
Sunrise, sunset and twilight times in February
February 1 NZDT February 31 NZDT morning evening morning evening SUN: rise: 6.24am, set: 8.43pm rise: 6.58am, set: 8.07pm Twilights Civil: starts: 5.56am, ends: 9.12pm starts: 6.32am, ends: 8.34pm Nautical: starts: 5.18am, ends: 9.50pm starts: 5.58am, ends: 9.08pm Astro: starts: 4.36am, ends:10.32pm starts: 5.23am, ends: 9.43pm
February phases of the moon (times as shown by guide)
First quarter: February 4 at 5.19 pm (04:19 UT) Full moon: February 11 at 1.33 pm (00:33 UT) Last quarter February 19 at 8.33 am (Feb 18, 19:33 UT) New moon: February 27 at 3.59 am (Feb 26, 14:59 UT)
Neither the penumbral eclipse of the Moon on February 11 nor the annular eclipse of the Sun on the 26th, are visible from New Zealand. Further details of both eclipses can be found on the RASNZ web page, <www.rasnz.org.nz/in-the-sky/eclipses>.
The planets in February 2017
Venus remains the obvious bright planet in the evening sky but gets considerably lower, setting earlier, during the month. Mars, much fainter, is only a few degrees higher. Jupiter begins to move into the late evening sky; in the morning sky it will be joined by Saturn and, during the first part of the month, by Mercury.
Evening planets, venus and mars
Venus will remain brilliant in the evening sky throughout February reaching magnitude -4.8 by the 28th. It will get much lower in the western sky during the month, setting before 9 pm, about 45 minutes after the Sun, at the end of February. The planet is in Pisces all month.
Mars will be about 5.5° above and to the right of Venus on the 1st, with the crescent moon less than 3° away on the other side of Mars. With a magnitude 1.1, while still quite bright, Mars will have less than 1% of the brilliance of Venus.
For the first few days of February the relative positions of two planets will change little, both moving to the east through the stars. Later in the month, as Venus' apparent motion slows, Mars will draw away from it. Venus is stationary early in March
Towards the end of February, Mars will pass Uranus. The two are closest on the evening of the 27th, when Uranus will be just over half a degree to the upper left of Mars. With a magnitude 5.9, Uranus will be an easy binocular object, with no star of a similar magnitude close by.
By the end of February Mars will set about 100 minutes after the Sun and nearly an hour later than Venus.
Late evening and morning
Jupiter rises near 11.30 pm on the 1st and 9.40 on the 28th. So by then it will be an obvious late evening object to the east. Anyone who has seen Jupiter in the morning sky recently will know that it is close to the first magnitude star Spica. Early in the month their separation will be 3.6°. On the 6th Jupiter is stationary, after that date it will start moving slowly to the west as the faster moving Earth begins to catch up with the planet. The resulting retrograde motion of Jupiter after the 6th will increase its distance very slightly from Spica.
On the night of the 15th and 16th the 80% lit waning moon will pass Jupiter. The two are closest at about 5 am on the 16th when the moon will be 3° below Jupiter with Spica 3.6° above the planet, the three forming a line near to dawn.
Saturn rises about 2.40 am on the 1st and an hour after midnight on the 28th. The planet is in Ophiuchus until the 21st when it moves into Sagittarius. The 32% lit waning moon will be 5° to the left of Saturn on the morning of February 21.
Saturn's ring system is now wide open as seen from the Earth. The planet's north pole is tilted towards us by over 26°. This is sufficient to bring the far edge of the ring system into view over the north pole of Saturn. Also the satellites, visible in a fairly small telescope, will appear scattered around the planet in a pattern changing from night to night.
Mercury rises about an hour and three-quarters before the Sun on February 1 so it should be visible in the morning sky about an hour before sunrise. The planet will then be a low 7° a little to the south of east. On the 1st Mercury is in Sagittarius at magnitude -0.2, it will be a little below the handle of the "teapot". During February Mercury moves out of Sagittarius, first into Capricornus on the 7th and then into Aquarius on the 24th. At the same time, its elongation from the Sun will steadily decrease. As a result the planet will be lost to view in the twilight glow by about the middle of the month.
The moon, as a very thin crescent, will be 5° to the left of Mercury on the morning of the 26th.
Uranus, at 5.8 to 5.9, remains in Pisces and is best observe early evening. On the 1st about 12.30 am and about 10.30 pm on the 28th. As noted above it is close to Mars at the end of the month giving an easy opportunity to locate the outer planet in binoculars. On the 2nd, the 30% lit waxing moon will be just under 3° to the upper left of Uranus.
Neptune is in Aquarius at magnitude 8.0 throughout February. Nominally in the evening sky, it will be too close to the Sun to observe. It sets just 7 minutes after the Sun on the 28th.
Pluto was at conjunction with the Sun on January 7, so will be moving into the morning sky during February. The planet is still in Sagittarius and will rise at 2.40 am on the 28th.
(1) Ceres is an early evening object. It starts the month in Pisces but moves across a corner of Cetus starting on the 13th. The asteroid is a 9th magnitude object.
(4) Vesta is also an evening object in February with a magnitude fading from 6.6 to 7.1 during the month. It will move to the west through Gemini and will be between 3 and 4° from beta Gem, Pollux, magnitude 1.2.
Four other asteroids brighten sufficiently to be visible in binoculars during the month. Three of them (9) METIS, (14) IRENE and (29) AMPHITRITE are in Leo, although Irene crosses a spur of Leo Minor from the 3rd to the 12th. The fourth, (15) Eunomia is in Sextans. All four brighten to between magnitude 9.0 and 9.2. Three of them are at opposition during February, Eunomia February 16/17, Irene February 23/27 and Metis the following night. Amphitrite brightens from 9.8 on the 1st to 9.2 on the 28th. It is at opposition in March.
Up to 3 comets May be visible in binoculars during February. Magnitudes shown are estimates for the whole comet, the nucleus is likely to be fainter.
P/Encke (2P) is in Pisces fairly close to Venus. It brightens during the month from magnitude 11.4 on the 1st to 5.5 on the 28th. Unfortunately as it brightens so it gets lower in the western early evening sky. By the 28th it will set only 34 minutes after the Sun making it virtually un observable.
P/Honda-Mrkos- Pajdusakova (45P) moves into the morning sky at the beginning of February. On the 8th it will be at magnitude 8.3. Two mornings later (10th) at 8.5 it will 6° to the lower left of alpha Oph (2.1). On the 13th 2° below alpha CrB (2.2) and on the mornings of 15 and 16 Feb at mag 9.2 it will be 12.5°below Arcturus (mag 0.2). Thus it will remain a very low object for NZ observers.
Brian Loader New Zealand