SkyEye

February 2021

Welcome to SkyEye, your guide to this month's celestial events.

The Calendar

Venus, Jupiter and Saturn cluster together low in the east just before sunrise during the first part of the month. Meanwhile, in the evening sky, the view of Mars through a telescope reveals a distinctly gibbous appearance as the red planet reaches east quadrature.

The phases of the Moon in February 2021

Date Body Event
1 Mars east quadrature
2
3 Moon farthest perigee of the year
4 Moon last quarter
5
6 Venus, Saturn conjunction: 0.4° apart
7 Mars equinox
Moon descending node
8 Mercury inferior conjunction
9 2 Pallas conjunction
10
11 Venus, Jupiter conjunction: 0.4° apart
Moon new
12
13 Mercury, Venus conjunction: 4.6° apart
14 Mercury, Jupiter conjunction: 3.9° apart
15
16
17
18 Jupiter 0.03° north of fourth-magnitude star θ Capricorni
Moon apogee
19 Moon first quarter
20 Venus aphelion
Mercury stationary point in right ascension: retrograde → direct
21 Moon ascending node
22
23
24
25
26
27 Moon full
28

The Solar System

The word planet is derived from the Greek word for 'wanderer'. Unlike the background stars, planets seem to move around the sky, keeping mostly to a narrow track called the ecliptic, the path of the Sun across the stars. Dwarf planets and small solar-system bodies, including comets, are not so constrained, often moving far above or below the ecliptic.

The position of the Sun and planets at mid-month

Sun CapricornusAquarius

Mercury CapricornusAquariusCapricornus

Mercury disappears in the west soon after the month begins, undergoing inferior conjunction on 8 February and reappearing later in the morning sky before sunrise. This is a poor apparition for planet chasers in northern temperate latitudes but the best morning appearance of the year for those in the southern hemisphere. Observers in the south will have the best chance of seeing Mercury move past bright Venus on 13 February and not-quite-as-bright Jupiter the following day. Retrograde ceases on 20 February and Mercury returns to direct motion.

Venus SagittariusCapricornusAquarius

The morning star appears just 0.4° south of Saturn and Jupiter on 6 February and 11 February respectively. Two days after the Jupiter appulse, Venus and Mercury come to within 5° of each other. Northern hemisphere observers will have particular difficulty observing any of these events as Venus is very near the horizon at sunrise. The magnitude −3.9 object reaches aphelion on 20 February.

Earth and Moon

The most distant lunar perigee of the year occurs this month, on the third.

Mars AriesTaurus

Red Mars is visible in the evening sky, best seen from northern skies where the planet doesn't set until after midnight. Its brightness is fading throughout the month, beginning at magnitude +0.4 and ending at around +0.9. On the first day of the month, Mars is at east quadrature, appearing 90° away from the Sun. A Martian equinox occurs on 7 February: spring comes to the northern hemisphere and winter takes hold in the south.

Jupiter Capricornus

The largest planet in the solar system was at conjunction very late last month and only begins to emerge in the dawn sky at the end of February. Southern hemisphere observers have the best views of Jupiter but its appulses with Venus (11 February) and Mercury (14 February) may occur too close to the Sun to be visible. The gas giant passes just 0.03° north of fourth-magnitude star θ Capricorni on 18 February, with closest approach occurring around 06:30 UT.

Saturn Capricornus

The ringed planet is still very close to the Sun at the beginning of the month, rendering its appulse with Venus on the sixth very difficult to see. Saturn is best viewed from the southern hemisphere where by mid-month it rises ahead of the dawn.

Uranus Aries

Uranus is visible in the evening and is best seen from northern latitudes where it sets around midnight. Look for the sixth-magnitude planet in the west during the first half of the month when the Moon is not flooding the sky with light. The waxing crescent Moon passes 3.0° south of Uranus on 17 February.

Neptune Aquarius

A small telescope is always necessary to view the most distant planet in the solar system. Neptune is setting during twilight by the end of the month so look for it in the west early in February. Northern hemisphere observers have the best chance to glimpse this eighth-magnitude object.

The Celestial Sphere

Constellations are patterns of stars in the sky. The International Astronomical Union recognises 88 different constellations. The brightest stars as seen from the Earth are easy to spot but do you know their proper names? With a set of binoculars you can look for fainter objects such as nebulae and galaxies and star clusters or some of the closest stars to the Sun.

Descriptions of the sky for observers in both the northern and southern hemispheres are available for the following times this month. Subtract one hour from your local time if summer (daylight savings) time is in effect.

Local Time Mid-month Northern Hemisphere Equator Southern Hemisphere
1730 hours (1830 hours summer time) 60° N 50° N 40° N 30° N 20° N 10° N 10° S 20° S 30° S 40° S
1930 hours (2030 hours summer time) 60° N 50° N 40° N 30° N 20° N 10° N 10° S 20° S 30° S 40° S
2130 hours (2230 hours summer time) 60° N 50° N 40° N 30° N 20° N 10° N 10° S 20° S 30° S 40° S
2330 hours (0030 hours summer time) 60° N 50° N 40° N 30° N 20° N 10° N 10° S 20° S 30° S 40° S
0130 hours (0230 hours summer time) 60° N 50° N 40° N 30° N 20° N 10° N 10° S 20° S 30° S 40° S
0330 hours (0430 hours summer time) 60° N 50° N 40° N 30° N 20° N 10° N 10° S 20° S 30° S 40° S
0530 hours (0630 hours summer time) 60° N 50° N 40° N 30° N 20° N 10° N 10° S 20° S 30° S 40° S