The Planets in February and March 2022.

In this period we have lost long line of planets previously visible in the early evening sky as some sink deeper into the glow of sunset and others move steadily past the Sun to become morning objects.

In February Mercury has very good morning apparition for equatorial regions and the southern hemisphere but is rather low as seen from the UK. Greatest Western Elongation (GWE) from the Sun, stretching to 26 degrees, occurs on the 16th but for mid-UK latitudes look for it at around 5 degrees above the south-eastern horizon from 0650UT any time between perhaps 05 and 21 February; however you won’t have long to see it before it is washed-out by the brightening sky. In this period Mercury itself brightens from magnitude +1.4 to +0.8 but its low altitude above the horizon means that atmospheric extinction (darkening by viewing through a thick air mass) will reduce its visibility by at least one magnitude.

Both Venus and Mars are nearby, some 15 degrees further south and noticeably higher and finding them may help in finding the innermost planet to the Sun around the date of its GWE; Venus will be very obvious but Mars is of similar brightness to Mercury. On 02 and 03 March Mercury passes very close to Saturn but this is unlikely to be seen from the UK unless you follow Saturn into daylight to view at higher altitudes. If you do, Mercury will sit less than a degree below the gas giant but the pair will be only 23 degrees from the risen Sun making this a risky, if interesting, observation.

Venus, as mentioned, is now also a morning object and a very splendid one too. In early February it rises in darkness around 0535UT somewhat south of due-east, shining at magnitude -4.6, bright enough to cast shadows if you are well away from light pollution, and reaches an elevation of 15 degrees above the south-eastern horizon by sunrise from the UK. Initially its phase will be small at some 15% illuminated and its angular size large, at 49 seconds of arc; a good time to look for the Ashen Light perhaps? By early March the phase will have risen to 38% illuminated and the apparent size fallen to 31 arcseconds as Venus moves away from us towards its own GWE from the Sun which occurs on the 20th of March. By that date Venus will reach only 10 or so degrees above the horizon at sunrise so it is better to observe it early in the period rather than at greatest elongation. By late March Venus is even lower by sunrise but will still be bright and obvious in the hour before that as long as you have a clear eastern horizon.

As mentioned Mars is also in the morning sky, keeping company with Venus; Mars initially sitting noticeably lower to the horizon and slightly further to the south. Brightening slowly from +1.4 to + 1.1 throughout the period, Mars remains below 10 degrees of elevation by sunrise so is a difficult object to observe. By late March the apparent size of Mars is just 4.3 arcseconds so it will be best seen later in the year.

Jupiter put on a lovely evening show earlier in the year but moves into conjunction behind the Sun on 05 March. This means you may just catch it before sunset in early to mid-February, low in the western sky, but after that you will have to wait until April to see Jupiter again, rising just before the Sun in the east.

Saturn had its own solar conjunction on 04 February so for most of the rest of the month is still too close to the Sun to observe as a morning object. By 02 March Saturn is rising some 30 minutes before the Sun but gains only 5 degrees of elevation in the south-east by sunrise making its conjunction with Mercury extremely hard to see on the 2nd and 3rd for UK observers. By late March things have improved slightly with Saturn sitting between Venus and Mars, forming a low altitude but interesting planetary grouping in the south-east, all three planets clearly visible at around 0500UT.

Uranus remains the sole observable evening object throughout this period. As darkness falls in early February Uranus can be found at more than 50 degrees of elevation above the southern horizon midway between Hamal in Aries and Menkar in Cetus. At magnitude +5.8 and just 3.6 arcseconds in apparent size you will need binoculars to find it and high power to resolve its visible disc however the planet can be followed in full darkness and at above 30 degrees of elevation for around 4 hours so it is well worth seeking out. By early March Uranus is sinking to the west as darkness falls but can still be found at 40 degrees of elevation at around 1900UT in early twilight. By late in the period Uranus will be too low for effective observation as darkness falls.

Neptune sits 10 degrees above Jupiter in very early February but is in solar conjunction on 13 March so is soon lost, becoming unobservable until early summertime.

Alan Clitherow.