Venus at dichotomy

Dominic Ford, Editor
From the Inner Planets feed


Objects: Venus

Venus will reach half phase in its 2019–2020 evening apparition. It will be shining brightly at mag -4.4.

From Fairfield , this apparition will be exceptionally well placed and prominent, reaching a peak altitude of 43° above the horizon at sunset on 26 Mar 2020.

2019–2020 evening apparition of Venus

14 Aug 2019 – Venus at superior solar conjunction
24 Mar 2020 – Venus at greatest elongation east
26 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 Fairfield local time.

Date Sun
sets at
Venus
sets at
Altitude
at sunset
Direction
at sunset
Mag Phase
27 Dec 201916:3019:0321°south-west-4.083%
06 Jan 202016:3819:2725°south-west-4.081%
16 Jan 202016:4919:5128°south-west-4.078%
26 Jan 202017:0120:1431°south-west-4.175%
05 Feb 202017:1320:3635°south-west-4.172%
15 Feb 202017:2620:5737°south-west-4.269%
25 Feb 202017:3821:1739°south-west-4.265%
06 Mar 202017:4921:3641°west-4.360%
16 Mar 202019:0022:5442°west-4.356%
26 Mar 202019:1123:1043°west-4.450%
05 Apr 202019:2223:2242°west-4.445%
15 Apr 202019:3323:2841°west-4.538%
25 Apr 202019:4323:2437°west-4.530%
05 May 202019:5423:0632°west-4.521%
15 May 202020:0422:2923°west-4.412%
25 May 202020:1421:3012°north-west-4.13%

A graph of the phase of Venus is available here.

Apparitions of Venus

03 Jun 2017 – Morning apparition
17 Aug 2018 – Evening apparition
06 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 that 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. These apparitions repeat roughly once every 1.6 years.

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.

Venus's phase

Venus's phase varies depending on its position relative to the Earth. When it passes between the Earth and Sun, for example, the side that is turned towards the Earth is entirely unilluminated, like a new moon.

Conversely, when it lies opposite to the Earth in its orbit, passing almost behind the Sun, it appears fully illuminated, like a full moon. However, at this time it is also at its most distant from the Earth, so it is actually fainter than at other times.

Venus shows an intermediate half phase – called dichotomy – at roughly the same moment that it appears furthest from the Sun, at greatest elongation. The exact times of the two events may differ by a few days, only because Venus's orbit is not quite perfectly aligned with the ecliptic.

Venus's position

The coordinates of Venus when it reaches dichotomy will be:

Object Right Ascension Declination Constellation Angular Size
Venus 03h16m50s 21°30'N Aries 24.1"
Sun 00h24m 2°35'N Pisces 32'03"

The coordinates above are given in J2000.0.

The sky on 26 Mar 2020

The sky on 26 March 2020
Sunrise
06:43
Sunset
19:11
Twilight ends
20:45
Twilight begins
05:10


Waxing Crescent

8%

2 days old

Planets
Rise Culm. Set
Mercury 05:49 11:18 16:46
Venus 08:26 15:49 23:13
Moon 08:09 14:40 21:20
Mars 03:49 08:31 13:13
Jupiter 03:33 08:16 12:59
Saturn 03:55 08:44 13:32
All times shown in EDT.

Source

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

26 Mar 2020  –  Venus at highest altitude in evening sky
13 Aug 2020  –  Venus at greatest elongation west
02 Sep 2020  –  Venus at highest altitude in morning sky
29 Oct 2021  –  Venus at greatest elongation east

Image credit

© NASA/Ricardo Nunes

Share