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The Solar System In April 2017

NZ reverts to NZST (UT +12 hours) on April 2 at 3am. Consequently dates and times shown are NZST apart for any on April 1.

Sunrise, sunset and twilight times in April

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

              April  1  NZDT                   April 30  NZST
              morning  evening                 morning  evening
 SUN: rise:   7.33am,  set:  7.15pm    rise:   7.04am,  set:  5.31pm
Twilights
Civil:    starts: 7.09am,  ends: 7.40pm    starts: 6.38am,  ends: 5.58pm
Nautical: starts: 6.37am,  ends: 8.12pm    starts: 6.05am,  ends: 6.30pm
Astro:    starts: 6.04am,  ends: 8.44pm    starts: 5.33am,  ends: 7.02pm

April phases of the moon (times nzst, as shown by guide)

          First quarter: April  4 at  6.40 am (Apr  3,  6:40 UT)
  Full moon:     April 11 at  6.08 pm (06:08 UT)
  Last quarter   April 19 at  4.07 pm (04:07 UT)
  New moon:      April 27 at 12.16 am (Apr 26, 12:16 UT)

The planets in April 2017

Jupiter becomes visible all night so is a brilliant object in the evening sky. Saturn will be to the east by late evening. Mars will be low to the west after sunset setting before the end of astronomical twilight. Venus moves up in the morning sky during April, a brilliant object to the east. Mercury is too close to the Sun to observe all month.

Mercury is virtually unobservable throughout April. It is at inferior conjunction between Earth and Sun at 5pm on the 20th. At conjunction the planet will pass 1.5° north of the Sun as "seen" from the Earth. Mercury will be 86 million km from the Earth and 64.4 million km from the Sun.

On the 1st Mercury, in the evening sky, will set only 30 minutes after the Sun. On the 30th, in the morning sky, it rises about 80 minutes before the Sun but at magnitude 2.6 is not likely to be visible due to twilight.

Venus is a morning object in April. On the 1st it will rise some 45 minutes before the Sun, by the 30th it will rise more than 3 hours earlier than the Sun.

The planet will not be readily visible on April 1 when it is only 12° from the Sun. Its distance from the Sun increases steadily throughout April, particularly early in the month as Venus moves to the west through the stars, away from the easterly moving Sun. This will make it an easy object within a few days. It will be visible a little to the north of east at first shortly before sunrise.

Venus is in Pisces all month and is stationary on April 13 after which it will start moving to the east but less rapidly than the Sun. The position of the planet relative to the stars will change little during the month

The morning of the 24th will find the crescent moon some 4.5° to the upper right of Venus

Mars will remain a low early evening object during April. On the 1st it sets just over 80 minutes after the Sun, dropping only slightly to 75 minutes later on the 30th. It will be low, with a magnitude 1.5, visible only briefly as the sky darkens following sunset. Mars will set a little before the end of Astronomical twilight so not be an easy object.

During April, the planet moves to the east through Aries and on into Taurus on the 12th. On the 21st and 22nd it will be 3.5° above the Pleiades, by the end of April Mars will be 7° below the similarly coloured star Aldebaran. On the 28th the moon, a very thin crescent less than 5% lit, will be 5° to the upper left of Mars.

Jupiter is at opposition on April 8, NZ time. At opposition Jupiter will be 4.5 AU, 666 million km from the Earth and a further 150 million km from the Sun. The planet will be in Virgo moving in a retrograde sense to the west as the Earth overtakes it. Jupiter starts the month just over 6° from Spica, its slow westerly motion taking it to nearly 9.5° from the star on the 30th.

The full moon will be 6.5° from Jupiter on the evening of April 11, the moon at the apex of an inverted triangle formed by it, Jupiter and Spica.

Saturn will rise close to 11 pm NZDT 1st of April, which becomes 10pm NZST on the 3rd with the time of rise advancing to just after 8 pm by the 30th. Thus it becomes a prominent later evening object to the east at magnitude 0.3 to the east during the month. It will, of course, be readily visible in the morning sky. By the end of April Saturn will be highest and due north about 3.40 am.

Saturn is stationary on the 6th, after which it will start moving to the west, but its position in Sagittarius will change little throughout the month.

The 75% lit waning moon will be 3.5° to the lower right of Saturn on the morning of April 17, with the two closest at about 6 am.

Outer Planets

Uranus is at conjunction with the Sun on April 14. Hence it will be too close to the Sun to observe throughout April.

Neptune, in the morning sky, rises about two and a half hours before the Sun on the 1st and nearly 5 hours earlier on the 30th. The planet is in Aquarius at magnitude 8.

Pluto, magnitude 14.4, is in the morning sky rising about 12.40 am, NZDT, on the 1st and 9.45 pm on the 30th. It will remain in Sagittarius just under 2.5° from the 2.9 magnitude star pi Sgr.

Minor Planets

(1) Ceres is an early evening object, brightening slightly from magnitude 9.1 to 8.9 during the month. It is quite close to Mars moving on a path almost parallel to the major planet which overtakes Ceres during the month. On the 1st they are 4° apart with Ceres above Mars. On the 8th they are at their closest, 3° apart. By the 30th Ceres is will be dropping behind Mars, the two then being 5° apart.

On the 12th both Ceres and Mars move from Aries to Taurus, with Ceres crossing the border shortly before Mars.

(4) Vesta, an evening object in April, is in Gemini. It passes Pollux, magnitude 1.2, early in April, the two being closest on April 7, just over 2° apart. The asteroid moves on into Cancer on the 24th. Vesta dims slightly during the month from magnitude 7.7 to 8.0. It sets about 12.45 am, NZDT, on the 1st and just before 10.30 pm, NZST, on the 30th.

Brian Loader  
New Zealand

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.

Outer Planets

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.

Minor Planets

(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