Look for Mercury farthest from the morning sun August 19

Mercury farthest from the sunrise on August 19

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 at 0 UTC on August 1, 2025, reaching the point astronomers call inferior conjunction. And since then, Mercury has been speeding ahead of Earth in orbit. It re-emerged in our morning sky in early August. Mercury will reach its greatest morning elongation – its greatest apparent distance from the rising sun – on August 19, 2025. Also, brilliant Venus and Jupiter are near Mercury in the morning sky.

Mercury greatest elongation, August 2025

When to watch: Officially, Mercury emerged in early August in the morning sky. Look for it about 30 minutes before sunrise. At greatest elongation – August 19, 2025 – 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 August 19 at 10 UTC (5:00 a.m. CDT). Mercury is shining at magnitude 0 that morning. And it’s 19 degrees from the sun.
Through a telescope on and around August 19, Mercury appears 42% illuminated, in a crescent phase, and 7.33 arcseconds across.
Note: Once you spot it, notice that Mercury brightens quickly as August progresses, reaching a magnitude of around -1.2 (bright, but competing with the morning twilight) late in August when it will slip away in the morning glare.

By the way, this Mercury elongation – due to the high angle of the ecliptic to the horizon – favors the Northern Hemisphere.

In the meantime, the innermost planet – named for the fleet-footed messenger god of the ancient Romans – will be visible for another week or two, especially from the Northern Hemisphere.

Finder charts for Mercury

The moon visits Mercury

Mercury part of a planet parade

For precise sun and Mercury rising times at your location:

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

Mercury events in 2025

Note: Times are in UTC

Feb 8, 2025: Superior conjunction (passes behind sun from Earth)
Mar 8, 2025: Greatest elongation (evening)
Mar 24, 2025: Inferior conjunction (races between Earth and sun)
Apr 21, 2025: Greatest elongation (morning)
May 30, 2025: Superior conjunction (passes behind sun from Earth)
Jul 4, 2025: Greatest elongation (evening)
Aug 1, 2025: Inferior conjunction (races between Earth and sun)
Aug 19, 2025: Greatest elongation (morning)
Sep 13, 2025: Superior conjunction (passes behind sun from Earth)
Oct 29, 2025: Greatest elongation (evening)
Nov 20, 2025: Inferior conjunction (races between Earth and sun)
Dec 7, 2025: Greatest elongation (morning)

Mercury charts from Guy Ottewell

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.

Heliocentric solar system, August 2025

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 will reach its greatest elongation – greatest distance from the sunrise – on August 19, 2025. Look east at dawn. It’ll disappear from the morning sky later by month’s end. Also, the brilliant planet Venus and bright Jupiter are near Mercury in the morning sky.