Mercury farthest from the sunrise this week

Mercury will reach its farthest angular distance from the sun at 3 UTC on December 25, 2024 (9 p.m. CST on December 24). Then it’ll be 22 degrees from the sunrise. No matter where you are on Earth, look east before sunrise to see Mercury now. The red star Antares will be nearby. Chart via EarthSky.

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Mercury farthest from the sunrise on December 25

The innermost planet Mercury orbits the sun every 88 days. And Earth is moving, too. So Mercury goes between us and the sun pretty often, about every 116 days. It did this last on December 6, 2024, reaching the point astronomers call inferior conjunction. And since then, Mercury has been speeding ahead of Earth in orbit. It re-emerged in our dawn around mid-month. Now, Mercury will reach its greatest morning elongation – its greatest apparent distance from the rising sun – on December 25, 2024.

By the way, this Mercury elongation does not favor either hemisphere.

In the meantime, the innermost planet – named for the fleet-footed messenger god of the ancient Romans – will be visible for a few more weeks.

Mercury greatest elongation, December 2024

When to watch: Officially, Mercury became visible toward the middle of December 2024 in the morning sky. Look for it about 40 minutes before sunrise. At greatest elongation – December 25, 2024 – Mercury is farthest from the sunrise on our sky’s dome. And after that, when it’ll be edging back toward the sunrise, it’ll brighten a little bit more, making Mercury easier to spot – although low – in the morning twilight.
Where to look: Look in the sunrise direction as the sky is getting lighter.
Greatest elongation is on December 25 at 3 UTC (9:00 p.m. CDT on December 24). Mercury is shining at -0.3 magnitude that morning. And it is 22 degrees from the sun.
Through a telescope on and around December 25, Mercury appears 69% illuminated, in a gibbous phase, and 6.4 arcseconds across.
Note: Once you spot it, notice that Mercury brightens quickly as December progresses, reaching a magnitude of around -0.4 (bright, but in bright morning twilight) by the end of the month. Mercury will slip away in the morning glare in January 2025.

Diagram: Orbits of Earth and Mercury with sun in center, and lines showing line of sight from Earth to Mercury.
At greatest elongation on December 25, 2024, Mercury lies to one side of the sun as seen from Earth. That’s when it’s at its greatest distance from the sun on our sky’s dome. Chart via EarthSky.

December finder charts for Mercury

Star chart with line looping up and back down for Mercury from December 15 to 25, and the star Antares nearby.
In the last half of December, the bright but elusive little planet Mercury will lie near the horizon in the morning twilight. Look for it about 40 minutes before sunrise. It’ll reach its farthest angular distance from the sun at 3 UTC on December 25, 2024 (9 p.m. CST on December 24). At that time, Mercury will be 22 degrees from the sun in our sky. It will lie near the the bright red star Antares in Scorpius the Scorpion.
Chart via EarthSky.
Star chart with line looping up and back down for Mercury from December 15 to 25, and the star Antares nearby
For Southern Hemisphere viewers, Mercury will lie low in the bright southeastern twilight thirty minutes before sunrise. The little planet might be difficult to spot. The bright star Antares will shine nearby. Chart via EarthSky.
Star chart showing 2 Moons on December 27 and 28 near 3 dots labeled Mercury, Antares and Zubenelgenubi.
On the mornings of December 27 and 28, 2024, the waning crescent moon will float above the eastern horizon near Mercury and Antares – the brightest star of Scorpius the Scorpion. Mercury will be disappearing from the morning twilight soon. Also nearby is the bright star Zubenelgenubi. Look for them about an 40 minutes before sunrise. Chart via EarthSky.

For precise sun and Mercury rising times at your location:

Old Farmer’s Almanac (U.S. and Canada)
timeanddate.com (worldwide)
Stellarium (online planetarium program)

Mercury events in 2024

Note: Dates are listed based on UTC times

Jan 12, 2024: Greatest elongation (morning)
Feb 28, 2024: Superior conjunction (passes behind sun from Earth)
Mar 24, 2024: Greatest elongation (evening)
Apr 11, 2024: Inferior conjunction (races between Earth and sun)
May 9, 2024: Greatest elongation (morning)
Jun 14, 2024: Superior conjunction (passes behind sun from Earth)
Jul 22, 2024: Greatest elongation (evening)
Aug 19, 2024: Inferior conjunction (races between Earth and sun)
Sep 5, 2024: Greatest elongation (morning)
Sep 30, 2024: Superior conjunction (passes behind sun from Earth)
Nov 16, 2024: Greatest elongation (evening)
Dec 5, 2024: Inferior conjunction (races between Earth and sun)
Dec 25, 2024: Greatest elongation (morning)

Mercury charts from Guy Ottewell

Sky chart with labeled constellations and objects, and positions of Mercury at elongations marked.
View larger. | Mercury’s greatest morning elongations in 2024 – from the Northern Hemisphere – as viewed through a powerful telescope. The planet images are at the 1st, 11th and 21st of each month. Here, dots show the actual positions of the planet for every day. Chart via Guy Ottewell’s 2024 Astronomical Calendar. Used with permission.
Sky chart with labeled constellations and objects, and positions of Mercury at elongations marked.
View larger. | Mercury’s greatest morning elongations in 2024 from the Southern Hemisphere, as viewed through a powerful telescope. The planet images are at the 1st, 11th and 21st of each month. Here, dots show the actual positions of the planet for every day. Chart via Guy Ottewell’s 2024 Astronomical Calendar. Used with permission.

A comparison of elongations

Mercury’s greatest elongations are not equal. Indeed, some are “greater” than others. For example, the distance of Mercury from the sun on our sky’s dome varies from about 28 degrees (maximum) to 18 degrees (minimum).

Also, Mercury elongations are better or worse depending on the time of the year they occur and your location on Earth. So, for both hemispheres, spring evenings and autumn mornings are best.

As an illustration, the chart below – from a Northern Hemisphere perspective – might help you visualize these differences.

Chart with row of steep, alternating light blue and gray arcs, each with a date and height in degrees.
Mercury elongations compared. Here, gray areas represent evening apparitions (eastward elongation). Blue areas represent morning apparitions (westward elongation). The top figures are the maximum elongations, reached at the top dates shown beneath. Curves show the altitude of the planet above the horizon at sunrise or sunset, for latitude 40 degrees north (thick line) and 35 degrees south (thin line). Likewise, maxima are reached at the parenthesized dates below (40 degrees north bold). Chart via Guy Ottewell’s 2024 Astronomical Calendar. Used with permission.

Heliocentric solar system, December 2024

Circle with sun at center, planets around, and zodiac names on outer edge.
Heliocentric view of solar system, December 2024. Chart via Guy Ottewell’s 2024 Astronomical Calendar. Used with permission.

Seasons make a difference

So, in the autumn for either hemisphere, the ecliptic – or path of the sun, moon and planets – makes a narrow angle to the horizon in the evening. Conversely, it makes a steep slant, nearly perpendicular, in the morning. So – in autumn from either hemisphere – morning elongations of Mercury are best. Then, Mercury appears higher above the horizon and farther from the glow of the sun. Conversely, evening elongations in autumn are harder to see.

On the other hand, in the spring for either hemisphere, the situation reverses. Then, the ecliptic and the horizon meet at a sharper angle on spring evenings and at a narrower angle on spring mornings. So, in springtime for either hemisphere, evening elongations of Mercury are best. Meanwhile, morning elongations in springtime are harder to see.

Bottom line: Mercury reaches its greatest elongation – greatest distance from the sunrise – on December 25, 2024. Look east at dawn. It’ll emerge around mid-month and brighten through the rest of December before disappearing from the morning sky in January.

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