The Night Sky in March 2017
The spring constellations of Leo, Hydra and Bootes are now high in the sky and visible all night whilst the galaxies of the Virgo cluster become prime objects for study. The giant planet Jupiter begins to dominate the night.
Moon in March:
New: 28th March
First quarter: 5th March
Full: 12th March
Last Quarter: 20th March
Planets in March:
Mercury: is at superior conjunction with the Sun on the 7th March and is not well placed for most of this month but it joins Mars and the crescent Moon in the west on the 29th.
Venus: begins to fade and draw in toward the Sun as it reaches inferior conjunction on 25th March. Early in the month is the best time to view its slim crescent.
Mars: Crosses into Aries by mid month and shines at magnitude 1.5. It sets by 9.30 and is still a tiny disc with no visible features in modest scopes.
Jupiter: Is a bright object in the constellation of Virgo, lying close to the first magnitude star Spica. Shining at magnitude -2.4, it rises by 9:50pm mid month and then dominates the sky for the rest of the night.
Saturn: Is in Sagittarius and is visible in the early morning, rising at 3:00am as a bright yellow star-like object shining at magnitude 0.5 low in the south east.
Uranus: Is in Pisces, and has a faint 6th magnitude disk that is shrinking as it comes into conjunction with the sun. The planet has set by 9:00pm mid month.
Neptune: The furthest planet from the Sun remains in Aquarius and is not visible this month as it attains conjunction on the 2nd of the month.
Meteor showers in March.
There are no major showers this month.
Interesting Events in March
The waxing crescent Moon is just to the south of Mars on the evening of the 1st March which may make a good photographic opportunity.
The dwarf planet Ceres, lately a target for the Dawn mission, enters the constellation of Aries on the 3rd March and shines at magnitude 8.5.
Two potentially interesting comets will grace northern skies in March. The first one, Comet 41P/Tuttle-Giacobini-Kresak will brighten to a potential magnitude of 5 in the latter part of the monthand will be sweeping through Draco and Hercules. Finder charts can be obtained at: http://www.cometwatch.co.uk/bright-comets-of-2017/41ptuttle-giacobini-kresak/
The second comet is not too far away in the northern sky from Comet 41P. Comet C/2015 V2 Johnson may reach 7th magnitude by the end of March as it comes to Perihelion. Finder charts and information can be found at: https://theskylive.com/c2015v2-info
Constellation of the Month: Hydra
Hydra is the longest and most sinuous constellation in the whole sky. In fact so long is it that its head is visible in winter, and its tail disappears mid-way through summer! Despite its length, Hydra is a constellation of faint stars, none of which rise to more than second magnitude. However, the head of Hydra is very distinctive, and once found, becomes the gateway to tracing out the rest of the constellation. Hydra lies under the constellations of Leo, Corvus, Crater and Virgo, but despite its association with such rich constellations, it does not have many deep sky objects of interest to the casual observer. In mythology, the Hydra is a snake associated in Babylonian records with waters and fountains and is the sign of the goddess Tiamat. In Greek mythology, Hercules killed this legendary monster as one of his 12 labours.
One of the finest deep sky wonders in Hydra is the star cluster M 48 which is a large irregular cluster of 50 or so stars in a fairly rich field close to the Milky Way, and lies adjacent to the constellation’s border with Monoceros. M 48 shines at magnitude 5.5; its stars are mostly A type giants which have a visual magnitude of 9th to 13th mag. The cluster lies 1500 light years away, and is famous in the Messier catalogue for its spurious position. The cluster in fact lies over 5 degrees away from the position Messier indicated. A beautiful sight in a small telescope or binoculars, and may even be visible to the naked eye on a night of exceptional “seeing”.
The next deep sky object deserving of attention is probably one of the most beautiful planetary nebulae in the night sky. This is NGC 3242 at RA 10h 24m 48s Dec -18°38m, an eighth magnitude disc of light that resembles the disc of a planet more than any other planetary in the sky. This object has on occasion been called the “Ghost of Jupiter” due to its uncanny resemblance. It lies over 2000 light years away, and is a marvellous sight in a small telescope, on high powers its lovely blue disc fills the field, and subtle shading indicates the presence of gaseous shells. This planetary can even be seen in binoculars on a good night, as a tiny star like disc.
The real showpiece of Hydra sadly, is not seen very well from Britain. This is the barred spiral galaxy M 83, which shines at eighth magnitude, but due to its southerly declination is extremely faint from these latitudes. It can be seen as an elongated blur of bluish light in a telescope, but binoculars may well provide a better view. M83 is relatively close by, only 10 million light years away, and may be an outlying member of our local group.
There are two globular clusters visible in Hydra, both rather unremarkable objects due to their southern aspect. One is M 68, a bright globular which shows little detail in a small telescope, but can be discerned as a 7th magnitude smudge of white light above the tail of Hydra. The other object is NGC 5694, which at magnitude 11 is beyond the grasp of most amateur instruments. It is another globular of fame, being very distant, and practically outside the confines of our galactic halo, on a par with NGC 2419 in Lynx. Hydra contains many double stars of note, but recourse to an album such as the Webb Deep Sky Society’s Binary Star handbook is recommended.