Solar System Phenomena — Venus in 2021

The path of Venus against the background stars in 2021

The upper chart shows the path of Venus across the background stars over the course of the year. Stars to magnitude +4.5 are shown with some fainter objects included to complete constellation patterns. The white circles represent the planet on the first day of the month and are scaled according to apparent magnitude. The faint paths before the first circle and after the last circle represent the planet's positions in December of last year and January of next. In general, the planet moves from right to left except when it's in retrograde and proceding in the opposite direction. As an inferior planet, Venus never strays far from the Sun so it always begins and ends the year near the constellation of Sagittarius, located about one quarter of the way in from the left side of the chart.

The lower charts show how the appearance of Venus changes over the year. Below each image is listed the date, the apparent magnitude, the apparent diameter of the disk (in arc-seconds), the geocentric distance (in au), the elongation from the Sun (in degrees) and the percentage of the disk which is illuminated. Like the Moon, Venus exhibits a complete range of phases, from new to crescent to gibbous to full and back again. Unlike the Moon, however, Venus takes over a year to complete this phase cycle. Note how Venus is at its brightest during its crescent phase, when it is relatively close to the Earth.

Venus begins the year as the morning star but it is already descending toward the eastern horizon. It has close encounters with both Jupiter and Saturn in early February but vanishes from view in early to mid-March. Superior conjunction occurs later that month and then Venus returns to the west after sunset where it remains as the evening star for the rest of the year. This is a disappointing apparition for observers in northern temperate latitudes but Venus puts on an excellent show for the southern hemisphere, rising high above the western horizon. Venus comes to within 0.4° of Mercury in late May and is found only 0.1° away from the open star cluster Praesepe in early July. Mars and the evening star are only half a degree apart shortly thereafter. Finally, a lunar occultation takes place on 8 November.

01 Januaryelongation 20.4°, illuminated fraction 94.1%, magnitude −3.9, disk diameter 10.8 arc-seconds
05 JanuaryOphiuchusSagittarius
11 January1.5° north of the Moon
16 Januarydescending node
01 Februaryelongation 13.1°, illuminated fraction 97.6%, magnitude −3.9, disk diameter 10.2 arc-seconds
06 Februaryplanetary conjunction: 0.4° south of Saturn
11 Februaryplanetary conjunction: 0.4° south of Jupiter
13 Februaryplanetary conjunction: 4.6° south of Mercury
20 Februaryaphelion
23 FebruaryCapricornusAquarius
01 Marchelongation 6.5°, illuminated fraction 99.4%, magnitude −3.9, disk diameter 9.9 arc-seconds
14 Marchplanetary conjunction: 0.4° south of Neptune
17 MarchAquariusPisces
26 Marchsuperior conjunction
27 MarchPiscesCetus
29 MarchCetusPisces
01 Aprilelongation 1.9°, illuminated fraction 100.0%, magnitude −3.9, disk diameter 9.8 arc-seconds
12 April2.9° north of the Moon
14 AprilPiscesAries
23 Aprilplanetary conjunction: 0.2° south of Uranus
25 Aprilplanetary conjunction: 1.1° south of Mercury
01 Mayelongation 9.2°, illuminated fraction 98.7%, magnitude −3.9, disk diameter 9.9 arc-seconds
03 MayAriesTaurus
09 Mayascending node
12 Maylunar occulation: 0.7° north of the Moon
29 Mayplanetary conjunction: 0.4° north of Mercury
01 Juneelongation 17.4°, illuminated fraction 95.3%, magnitude −3.9, disk diameter 10.4 arc-seconds
02 JuneTaurusGemini
05 Junemaximum declination north
12 June1.5° south of the Moon
25 JuneGeminiCancer
01 Julyelongation 25.3°, illuminated fraction 89.9%, magnitude −3.9, disk diameter 11.3 arc-seconds
03 July0.1° north of the open star cluster M44 (known as Praesepe or the Beehive Cluster)
11 JulyCancerLeo
13 Julyplanetary conjunction: 0.5° north of Mars
21 July1.0° north of Regulus
01 Augustelongation 33.0°, illuminated fraction 82.2%, magnitude −4.0, disk diameter 12.8 arc-seconds
10 AugustLeoVirgo
29 Augustdescending node
01 Septemberelongation 39.8°, illuminated fraction 72.9%, magnitude −4.0, disk diameter 15.2 arc-seconds
05 September1.4° north of Spica
18 SeptemberVirgoLibra
01 Octoberelongation 44.9°, illuminated fraction 62.2%, magnitude −4.2, disk diameter 19.0 arc-seconds
02 Octoberaphelion
07 OctoberLibraScorpius
09 October2.9° south of the Moon
15 OctoberScorpiusOphiuchus
16 OctoberOphiuchusScorpius
1.4° north of Antares
21 OctoberScorpiusOphiuchus
28 Octoberdichotomy
29 Octobergreatest elongation east: 47.0°
01 Novemberelongation 47.0°, illuminated fraction 48.1%, magnitude −4.4, disk diameter 25.8 arc-seconds
02 NovemberOphiuchusSagittarius
07 Novembermaximum declination south
08 Novemberlunar occultation: 1.1° south of the Moon
01 Decemberelongation 41.6°, illuminated fraction 28.6%, magnitude −4.7, disk diameter 39.1 arc-seconds
07 December1.9° north of the Moon
12 Decembermaximum magnitude −4.7
18 Decemberstationary point in right ascension: direct → retrograde
20 Decemberascending node
29 Decemberplanetary conjunction: 4.2° north of Mercury


The dates, times and circumstances of all planetary and lunar phenomena were calculated from the JPL DE406 solar system ephemeris using the same rigorous methods that are employed in the compilation of publications such as The Astronomical Almanac. Dates of dichotomy are taken from 'Theoretical Dichotomy of Venus, 2000–2040', Jean Meeus, Journal of the British Astronomical Association, 110 (2), 83 (April 2000).