The Solar System in May 2016
Dates and times shown are NZST (UT + 12 hours) unless otherwise stated.
Rise and set times are for Wellington. They will vary by a few minutes elsewhere in NZ.
Sunrise, sunset and twilight times in May
May 1 NZST May 31 NZST morning evening morning evening SUN: rise: 7.05am, set: 5.29pm rise: 7.33am, set: 5.03pm Twilights Civil: starts: 6.39am, ends: 5.56pm starts: 7.05am, ends: 5.31pm Nautical: starts: 6.07am, ends: 6.29pm starts: 6.31am, ends: 6.06pm Astro: starts: 5.34am, ends: 7.01pm starts: 5.58am, ends: 6.39pm
May PHASES OF THE MOON (times as shown by GUIDE)
New moon: May 7 at 7.30 am (May 6, 19:30 UT) First quarter: May 14 at 5.02 am (May 13, 17:02 UT) Full moon: May 22 at 9.14 am (May 21, 21:14 UT) Last quarter May 30 at 12.12 am (May 29, 12:12 UT)
The planets in May
Mercury is at inferior conjunction on May 9 when it will transit the Sun, an event visible from the opposite side of the Earth to NZ. After conjunction Mercury becomes a morning object and will be readily visible towards the end of May. Mars is at opposition on May 22 when it will be as bright as Jupiter. Mars will be close to Antares and Saturn.
Mercury starts May as an evening object, but sets only 24 minutes after the Sun on the 1st, so is not observable. It is at inferior conjunction between the Earth and Sun on the morning of May 10 NZST.
At the May conjunction Mercury will transit the Sun. The transit starts at 11:12 pm on 9 May (NZST) and ending at 6:42 am on 10 May (NZST); UT date and times are May 9, 11:12:18 and 18:42:14 respectively. The end is about half an hour before sunrise at Wellington. Thus the transit is not visible from New Zealand nor from Australia. The Middle East, Europe and Africa are well placed for viewing the start of the transit, the later stages are visible from the Americas. Apart from much of the Atlantic Ocean, Greenland and Brazil are the best places for seeing the entire event.
After conjunction Mercury becomes a morning object moving away from the Sun fairly rapidly. By May 24 the planet, at magnitude 1.8 will be some 7.5° above the horizon an hour before sunrise. A week later Mercury, now magnitude 1.0, will be nearly 10° up an hour before sunrise. Look for Mercury in a direction about 25° north of east.
Venus, in the morning sky, is close to the Sun all month. At the start of May its elongation is 10° with the planet rising 50 minutes before the Sun. By the 31st it will rise only 9 minutes before the Sun. So viewing is going to be difficult.
Mars, which has been steadily brightening recently, is at opposition on May 22. At magnitude -2.1 it will briefly be as bright as Jupiter. Mars will be close to Antares, the two just under 9° apart. The star at magnitude 1.1 is looking almost dim compared to the planet. Saturn will be about 12° from Mars and on the evening of May 22, the just past full moon will be 9° distant.
Mars is closest in its orbit to the Earth on May 31 when the two will be just over 75 million kilometres apart.
Jupiter will be best placed for viewing early evening, although it doesn’t set until after midnight. The planet is in Leo, its position changes little during the month, being stationary on May 10.
The 66% lit moon will be just over a degree from Jupiter on May 15.
Saturn rises an hour and three quarter after the Sun sets on May 1, and just 6 minutes after sunset on the 31st. So it is best viewed later evening. The planet, in Ophiuchus, is a few degrees from Antares. Saturn’s magnitude brightens from 0.2 to 0.0 during the month.
The moon passes Saturn on the 22nd but will be closest well after they set in NZ. The two are about 7° apart on the evening of May 22 and about 7.5° apart the following evening with the moon the opposite side of Saturn.
Uranus is a morning object in Pisces at magnitude 5.9. It rises about 100 minutes before the Sun on the 1st increasing to 4 hours earlier on the 31st.
Neptune is in the morning sky, rising just after midnight by May 31. The planet, at magnitude 7.9 is in Aquarius. Neptune is moving to the east past the 3.7 magnitude star lambda Aqr. The two are closest mid month when less than half a degree apart. Neptune will be to the upper right of the star. No stars as bright as Neptune are between the two.
Pluto at magnitude 14.4 rises close to 9.30 at the start of May and 2 hours earlier by the end of the month. The planet remains in Sagittarius less than 1° from the 2.9 magnitude star pi Sgr.
(1) Ceres, magnitude 9.3, is in Cetus during May. It rises just before 4 am on the 1st and just over an hour earlier by the 31st.
(4) Vesta, magnitude 8.4, is in Taurus. Its starts May as an evening object setting less than an hour after the Sun. It is at conjunction with the Sun on the 24th when the two will appear about 3.5° apart.
(7) Iris is at opposition on May 29 with a magnitude 9.2. The asteroid will be in Ophiuchus, 3° from Antares, just under 6° from Saturn and 9.5° from Mars. The 5th magnitude star rho Oph will be just over 13 arc minutes from Iris. The star has two close companions easily visible in binoculars at magnitudes 6.8 and 7.3, each about 2.5 arc minutes from brighter star.
Brian Loader New Zealand