Venus, Saturn and Mars join the Moon for a morning meeting
BEST TIME TO SEE: All month
The morning sky is getting interesting this month as a trio of planets jostle for position. The group consists of Venus, Mars and Saturn, which all appear rather low when they are observed from the UK. Dimmer Mars and Saturn take advantage of the fact that they appear close to the bright planet Venus which, currently shining at mag. –4.4, is considerably easier to see despite its low pre-sunrise altitude.
At the start of March, Mars rises approximately 90 minutes before the Sun, popping up above the southeast horizon while 5˚ south of Venus. Mars will be shining at mag. +1.3 on this date, and easy to recognise because of its orange hue.
On 8 March, the gap will have closed between Venus and Mars, the separation being 4.3˚ on this date. Mars will be a fraction brighter too, at mag. +1.2.
By 13 March, the gap will have dropped to a fraction less than 4˚. It’s about this time that mag. +0.9 Saturn may be glimpsed, rising 30 minutes after Mars. Venus remains close to Mars over the next few mornings, only starting to separate from the Red Planet around 18 March. Mars, Venus and Saturn will be contained within a circle 12˚ across on this date.
By 23 March, the containing circle will have reduced in size to 8.5˚, the three planets now quite tightly packed together. It’s fascinating to watch the pattern formed by the trio change shape over the remainder of the month. On the morning of 24 March, they form a squat isosceles triangle, with Venus as the upper vertex. Mars will have brightened to mag. +1.1 on this date. All three planets are above the horizon 60 minutes before the Sun, but will need at least 20 minutes longer to reach a visible altitude.
An altitude-challenged waning crescent Moon joins the group on 28 March. Located 5˚ below Mars, the 18%-lit waning crescent rises around 40 minutes before the Sun above the southeast horizon.
By 31 March, all three planets are contained within an area 6˚ across. Venus appears east of the group on this date, shining at mag. –4.2 and the easiest to see by far. Meanwhile, Saturn remains at mag. +0.9, just 3˚ from Venus with mag. +1.1 Mars now 3.3˚ from Saturn.
As March transitions into April, Venus leaves Mars and Saturn, the dimmer pair reducing their separation to just 19 arcseconds on 5 April. On that date, it will be possible to catch all three planets rising around the same time, approximately 80 minutes before the Sun above the east-southeast horizon.