Your guide to the night sky this month
WEDNESDAY The waxing crescent Moon (12% lit) is 4º south-southeast of mag. +5.9 Uranus and 4.9º south of mag. +1.3 Mars this evening. The planets are separated by 2º, Uranus lying to the southwest of Mars. THURSDAY Jupiter is wellpositioned for a moon and shadow transit of Ganymede this evening. The shadow transit starts at 22:39 UT on 2 March, ending at 01:10 UT on 3 March. Ganymede transits between 02:06 UT and 04:02 UT on the 3rd.
SATURDAY A lunar occultation of the Hyades cluster in Taurus begins at 20:00 UT. The Moon sets before the occultation ends.
Outer Galilean moon Callisto is just off Jupiter’s northern limb at 22:00 UT. Io can also be seen off Jupiter’s western limb at this time. FRIDAY 10 There’s another chance to catch Ganymede and its shadow transiting Jupiter this morning. The shadow transit occurs between 02:37 UT and 05:06 UT, the moon transit between 05:30 UT and 07:26 UT. SATURDAY 11 This evening Uranus sits just 11 arcseconds from the mag. +8.3 star HIP 6513 in Pisces. Look from 20:00 UT, when the star will lie just 3 arcseconds from Oberon, the outermost of Uranus’s bright moons. TUESDAY 14 The Moon appears close to mag. +2.7 Porrima (Gamma (a) Virginis) at 00:13 UT, with a true occultation visible from Cornwall and southwest Ireland. It sets after dawn; when it rises again at around 21:00 UT, it’ll be just 1.8º from mag. –2.2 Jupiter. WEDNESDAY 15 Jupiter appears to have an extra moon this evening. This is because it is passing close to the mag. +10.8 star TYC 4964-1346-1. The planet rises around 20:30 UT. MONDAY 20 Saturn and the waning gibbous Moon (54% lit) appear 4º apart at 04:00 UT.
The northern hemisphere’s spring equinox occurs at 10:29 UT. WEDNESDAY 22 Ninthmagnitude comet C/2015 V2 Johnson is approximately 3º from mag. +9.4 globular cluster NGC 6229 in Hercules from now until the end of the month.
SATURDAY 25 The Moon visible in the morning sky shows a favourable libration for the western limb.
Venus reaches inferior conjunction, after which it will be a morning planet. See this month’s Sky Guide Challenge. SUNDAY 26 The clocks go forward at 01:00 UT, marking the start of British Summer Time (BST). BST is one hour ahead of UT. WEDNESDAY 29 Mag. –0.3 Mercury is 8º north of a thin waxing crescent Moon (3% lit) at 20:30 BST (19:30 UT) in twilight. They form a celestial triangle with Mars. Look for all three low in the west. THURSDAY 30 Mag. +1.5 Mars is 6º north of tonight’s waxing crescent Moon (9% lit). See them together with mag. –0.2 Mercury low in the west from 20:30 BST (19:30 UT).
THURSDAY 9 Tonight’s waxing gibbous Moon (92% lit) shows a favourable libration for the eastern limb, bringing features such as the Mare Marginis and the Mare Humboldtianum into view. SUNDAY 19 It’s inner Galilean moon Io’s turn to transit Jupiter. Watch from 23:30 UT. The moon’s shadow begins its passage at 23:44 UT, with Io following suit at 00:11 UT on the 20th. The shadow transit ends at 01:55 UT, while the moon leaves the disc at 02:21 UT. FRIDAY 24 Jupiter is close to mag. +11.8 star GSC 4964-597. As darkness falls, star and planet are 5 arcminutes apart. By dawn twilight on the 25th, the gap will be 2.5 arcminutes. At 03:29 UT on the 25th – the star will be 8 arcseconds from Ganymede. TUESDAY 28 Seventh-magnitude comet 41P/ Tuttle-GiacobiniKresak is located to the north of the Plough’s pan. FRIDAY 31 This evening the waxing crescent Moon (18% lit) is close to the Hyades and Pleiades open clusters in Taurus.