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Venus before sunrise: Greatest elongation March 20

Venus before sunrise: Chart showing annotated red and white circles on a blue background with a green line diagonally across.
Both Southern and Northern Hemisphere skywatchers can now spot 3 planets – Venus, Mars and Saturn – in the eastern sky shortly before sunrise. This is the Northern Hemisphere view. Notice the shallow angle of the ecliptic (the green line) with respect to the horizon, on spring mornings. Venus will reach its greatest elongation – its greatest apparent distance from the sun in our sky – on March 20, 2022. Chart by John Jardine Goss.

See Venus before sunrise

The brightest planet – Venus – orbits the sun one step inward from Earth. So we always see it near the sun in our sky, either east before sunrise, or west after sunset. It’s always beautiful, and interesting. But there’s always a time when Venus appears farthest from the sunrise or sunset. And now’s the time. Astronomers call it a greatest elongation of Venus. You’ll easily see Venus now, shortly before sunrise, above (or to one side) of the sunrise point. The moment of greatest elongation happens at 9 UTC (4 a.m. CDT) on March 20, 2022. Clouded out? Never fear. Venus is always a sight to see!

Even better, Venus has company! Spot Mars and Saturn not far from dazzling Venus.

At this greatest elongation, Venus will be about 46 degrees from the sun on the sky’s dome. In the Northern Hemisphere, the angle of the ecliptic – the path of the planets and sun across our sky – is shallow at this time of year. That means Venus will be above the southeastern horizon shortly before sunup. The view is better in the Southern Hemisphere on March mornings. From the southern part of Earth’s globe, the ecliptic is angled steeply with respect to the horizon. So Venus appears higher up, in a darker sky, before sunrise.

By coincidence, this greatest elongation of Venus occurs within hours of the March equinox.

Diagram with a slanted ecliptic and an almost vertical ecliptic, with text annotations.
As seen from either the Northern or Southern Hemisphere, the angle of the ecliptic – pathway across our sky of the sun, moon and planets – is shallow on spring mornings and steep on spring evenings. And it’s steep on autumn mornings and shallow on autumn evenings. In the Northern Hemisphere now, the low angle of the ecliptic keeps Venus – and Mars and Saturn – to one side of the sunrise point. So they are visible in the southeastern sky. In the Southern Hemisphere now, where it’s autumn, the angle of the morning ecliptic is steep. So, from southerly latitudes now, Venus – and Mars and Saturn – can be seen due east, in a line extending up from the sunrise point. Note: this illustration shows the evening, not the morning, view. Image via Dominic Ford/ In-the-Sky.org.

Venus and friends

Venus is an unmistakable beacon of light near the horizon before sunrise. It shines at magnitude -4.4. Our closest planetary neighbor is currently among the stars of Capricornus the Sea-Goat.

You might also notice two other points of light near Venus, also in front of Capricornus. The point of light closest to Venus might look a little red to you. That’s because it’s Mars, the Red Planet, shining at magnitude 1.1 around mid-March 2022. A bit farther away and closer to the horizon is golden Saturn. Saturn is technically a bit brighter than Mars around mid-March 2022 at magnitude 0.8. But because Saturn is closer to the light of the rising sun, it won’t necessarily be easier to see.

Venus before sunrise: Rising times

Here’s when to start looking for Venus in the morning sky, based on your location:

60 degrees north latitude (Anchorage, Alaska, for example): Venus rises about one hour before the sun
40 degrees north latitude (Denver, Colorado, for example): Venus rises about 2 hours before the sun
Equator, 0 degrees latitude (Singapore, for example): Venus rises about 3 hours before the sun
40 degrees south latitude (Wellington, New Zealand, for example): Venus rises almost 4 hours before the sun

Want more specific information? Click here for a sky almanac.

Spring versus fall elongations

Morning elongations of Venus (or Mercury) are best in the fall. These elongations, called western elongations, have a steeper path above the horizon. Springtime elongations that occur in the morning are less glorious because of the shallow angle of the planets, which keeps them closer to the bright sun’s rays.

The angle of the ecliptic is what determines how high or low Venus is after sunset or before sunrise. The angle in the evening is low to the horizon in autumn and steep in spring. In the morning, this is the opposite. The angle is low to the horizon in spring and steep in the fall. As the sun, moon and planets travel on the ecliptic when the angle is steep, a planet appears farther above the horizon and is visible for longer in a dark sky. Therefore, greatest elongations west, or in the morning, are better in the fall. Greatest elongations east, or those in the evening, are best in the spring.

Diagram of two concentric orbits showing line of sight views of Mercury from Earth.
An inferior planet – a planet that orbits the sun inside of Earth’s orbit – appears in the evening sky at its greatest eastern elongation, and in the morning sky at its greatest western elongation. The two inferior planets are Mercury and Venus, residing at a mean distance of 0.387 and 0.723 astronomical units from the sun, respectively. This diagram applies to both Mercury and Venus. Image via Wikimedia Commons.

Bottom line: See Venus before sunrise. The brilliant planet reaches greatest elongation – farthest from the sun on the sky’s dome – on March 20, 2022. Look east before the sun comes up.

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