Mercury is in the evening sky until 28 October

Georgetown, Guyana · times in GMT-4. Best evening for Mercury: 11 October 2026, 14.6° high in the west-south-west at civil twilight.

Venus is in the evening sky until 12 October.

Mercury apparitions to 2028

Venus apparitions to 2028

Evening star, morning star

Mercury and Venus orbit inside Earth's orbit, so from here they never stray far from the Sun. Each one swings out to one side of the Sun, back behind or in front of it, and out to the other side.

• An apparition runs from one conjunction with the Sun to the next.
• After the planet passes behind the Sun (superior conjunction), it shows in the evening sky, in the west after sunset.
• After it passes between Earth and the Sun (inferior conjunction), it shows in the morning sky, in the east before sunrise.
• Greatest elongation is the day it is farthest from the Sun in the sky. The best night for viewing is often a day or two away from it.

Venus is so bright that it is easy once it is a little way from the Sun. Mercury is fainter and never far from the Sun, so it is only seen low in twilight, on a few weeks of each apparition.

Why the ratings use civil twilight

The heights on this page are taken at civil twilight, when the Sun's centre is 6° below the horizon. That is about 20 minutes after sunset (or before sunrise) in Guyana. The sky is still bright, but Mercury and Venus are already showing and have not yet sunk into the haze near the horizon. The dark-sky window used by other tools on this site starts much later, at 18° below, and is not used here.

The rating is a guide, not an astronomical standard:

• Good: at least 10° up and magnitude +1.0 or brighter.
• Fair: at least 5° up and magnitude +2.0 or brighter for Mercury (Venus is always bright enough).
• Poor: above the horizon, but lower or fainter than fair.
• Not visible: below the horizon at civil twilight.

A fair or good night is not a promise: haze, cloud and trees on the horizon hide low planets. On poor nights you may need binoculars, and the phase of either planet needs a telescope.

Low latitude helps

Near the equator, the planets set almost straight down after the Sun, so they stand higher in twilight than they do far from the equator. At Mercury's greatest elongation of 12 October 2026, it is 14.6° up at Georgetown's civil dusk, but only 3.3° up at New York's.

Safety

When Mercury or Venus is close to the Sun, the Sun may still be up or just below the horizon. Never sweep binoculars or a telescope across the sky while the Sun is up, and only look at the Sun through a certified ISO 12312-2 solar filter.

How the numbers were made

• Every night was computed with astronomy-engine 2.1.19 at civil twilight for the town you choose, with normal atmospheric refraction.
• Heights and directions agree with JPL Horizons to 0.01°, sizes to 0.01 arcseconds and phases to 0.1 percentage points.
• Civil twilight agrees with the US Naval Observatory to the minute; times are rounded to the nearest minute.
• Magnitudes are models and can differ by up to 0.15 from other sources, so they are given to one decimal.

Sources

• JPL Horizons (NASA Jet Propulsion Laboratory) for positions, sizes and phases.
• US Naval Observatory rise, set and twilight times.
• astronomy-engine 2.1.19 (Don Cross, MIT licence).