© NASA/Ricardo Nunes

Venus at greatest elongation east

Dominic Ford, Editor
From the Inner Planets feed

Objects: Venus
Please wait
Loading 0/4
Click and drag to rotate
Mouse wheel to zoom in/out
Touch with mouse to dismiss
The sky at

Venus will reach its greatest separation from the Sun in its 2019–2020 evening apparition. It will be shining brightly at mag -4.4.

From San Luis Obispo , this apparition will be well placed and prominent, reaching a peak altitude of 44° above the horizon at sunset on 24 Mar 2020.

Begin typing the name of a town near to you, and then select the town from the list of options which appear below.

2019–2020 evening apparition of Venus

13 Aug 2019 – Venus at superior solar conjunction
24 Mar 2020 – Venus at greatest elongation east
24 Mar 2020 – Venus at highest altitude in evening sky
26 Mar 2020 – Venus at dichotomy
28 Apr 2020 – Venus at greatest brightness
03 Jun 2020 – Venus at inferior solar conjunction

The table below lists the altitude of Venus at sunset over the course of the apparition. All times are given in San Luis Obispo local time.

Date Sun
sets at
sets at
at sunset
at sunset
Mag Phase
24 Dec 201916:5719:2123°south-west-4.084%
03 Jan 202017:0519:4426°south-west-4.082%
13 Jan 202017:1320:0429°south-west-4.079%
23 Jan 202017:2320:2533°south-west-4.176%
02 Feb 202017:3320:4336°south-west-4.173%
12 Feb 202017:4121:0239°south-west-4.170%
22 Feb 202017:5121:2041°south-west-4.266%
03 Mar 202018:0121:3242°west-4.262%
14 Mar 202019:0922:4944°west-4.357%
24 Mar 202019:1823:0244°west-4.452%
03 Apr 202019:2623:1444°west-4.446%
13 Apr 202019:3523:1942°west-4.539%
23 Apr 202019:4423:1339°west-4.532%
03 May 202019:5022:5934°west-4.523%
13 May 202020:0122:2626°west-4.413%
23 May 202020:0921:3215°west-4.25%

Altitude of Venus at sunset

A graph of the angular separation of Venus from the Sun around the time of greatest elongation is available here.

Apparitions of Venus

02 Jun 2017 – Morning apparition
17 Aug 2018 – Evening apparition
05 Jan 2019 – Morning apparition
24 Mar 2020 – Evening apparition
13 Aug 2020 – Morning apparition
29 Oct 2021 – Evening apparition
20 Mar 2022 – Morning apparition

Observing Venus

Venus's orbit lies closer to the Sun than the Earth's, meaning it always appears close to the Sun and is lost in the Sun's glare much of the time.

It is observable for a few months each time it reaches greatest separation from the Sun – moments referred to as greatest elongation.

On these occasions, Venus is so bright and conspicuous that it becomes the third brightest object in the sky after the Sun and Moon. It is often called the morning star or the evening star.

These apparitions repeat roughly once every 1.6 years, taking place alternately in the morning and evening skies, depending whether Venus lies to the east of the Sun or to the west.

When it lies to the east, it rises and sets a short time after the Sun and is visible in early evening twilight. When it lies to the west of the Sun, it rises and sets a short time before the Sun and is visible shortly before sunrise.

At each apparition, Venus reaches a maximum separation from the Sun of around 48°. However, some times of the year are more favourable for viewing Venus than others. From San Luis Obispo, it reaches a peak altitude of between 21° and 47° above the horizon at sunset during each evening apparition, depending on the time of year. During its 2019–2020 apparition, it will peak at 44° above the horizon at sunset on 24 Mar 2020.

This variability over the course of the year is due to the inclination of the ecliptic to the horizon.

The inclination of the ecliptic to the horizon

The inclination of the ecliptic to the horizon changes over the course of the year, affecting how high planets close to the Sun appear in the sky.

At all times, Venus lies close to a line across the sky called the ecliptic, which is shown in yellow in the planetarium above. This line traces the path that the Sun takes through the zodiacal constellations every year, and shows the plane of the Earth's orbit around the Sun. Since all the planets circle the Sun in almost exactly the same plane, it also closely follows the planes of the orbits of the other planets, too.

When Venus is widely separated from the Sun, it is separated from it along the line of the ecliptic. But, at different times of year, the ecliptic meets the horizon at different angles at sunset. This would translate into Venus being at different altitudes above the horizon, even if its separation from the Sun was constant.

If the ecliptic meets the horizon at a shallow angle, then Venus has to be very widely separated from the Sun to appear much above the horizon. Conversely, if the ecliptic is almost perpendicular to the horizon, Venus may appear much higher in the sky, even if it is actually much closer to the Sun.

The seasonal dependence of this is that at sunset, the ecliptic makes its steepest angle to the horizon at the spring equinox – in March in the northern hemisphere, and in September in the southern hemisphere. Conversely, it meets the horizon at its shallowest angle at the autumn equinox. Because the seasons are opposite in the northern and southern hemispheres, a good apparition of Venus in one hemisphere will usually be badly placed in the other.

At sunrise, these dates are also inverted, so that for morning apparitions of Venus, the ecliptic makes its steepest angle to the horizon at the autumn equinox, and its shallowest angle to the horizon at the spring equinox.

The optimum time for an apparition of Venus

The maximum altitude of Venus during all its evening apparitions between 2000 and 2050, as a function of the day of the year on which greatest western elongation occurs. Different colours show the altitudes observed from different latitudes. Click to expand.

For this reason, the day when Venus reaches its widest separation from the Sun (greatest elongation) is not necessarily the same day when it appears highest in the sky at sunset. Venus typically appears highest in the sky a few days or weeks closer to the spring equinox than the moment of greatest elongation.

The inclination of the ecliptic plane to the horizon at San Luis Obispo varies between 78° (sunset at the spring equinox) and 31° (sunset at the autumn equinox). On March 24, the ecliptic is inclined at 78° to the western sunset horizon, as shown by the yellow line in the planetarium above, meaning that this apparition of Venus will be well placed and prominent, reaching a peak altitude of 44° above the horizon at sunset.

Venus's position

The position of Venus when it reaches greatest elongation will be:

Object Right Ascension Declination Constellation Magnitude Angular Size
Venus 03h06m10s +20°35' Aries -4.4 23.4"
Sun 00h14m +01°31' Pisces -26.7 32'04"

The coordinates above are given in J2000.0.

The sky on 24 March 2020
Twilight ends
Twilight begins

30-day old moon
Waning Crescent


30 days old

Rise Culm. Set
Mercury 05:55 11:27 17:00
Venus 08:52 15:57 23:02
Moon 07:29 13:35 19:45
Mars 03:46 08:43 13:40
Jupiter 03:34 08:32 13:31
Saturn 03:59 09:01 14:04
All times shown in PDT.


The circumstances of this event were computed using the DE430 planetary ephemeris published by the Jet Propulsion Laboratory (JPL).

This event was automatically generated by searching the ephemeris for planetary alignments which are of interest to amateur astronomers, and the text above was generated based on an estimate of your location.

Related news

24 Mar 2020  –  Venus at greatest elongation east
26 Mar 2020  –  Venus at dichotomy
28 Apr 2020  –  Venus at greatest brightness
03 Jun 2020  –  Venus at inferior solar conjunction

Image credit

© NASA/Ricardo Nunes



San Luis Obispo



Color scheme