Why is Venus so bright in our Earth’s sky?

View at EarthSky Community Photos. | Karthik Easvur in Delhi, India, captured these 2 images on September 12, 2023. They show a crescent moon – and a crescent planet Venus – on the same evening. “It was just amazing,” he wrote. You need a telescope to see Venus as a crescent. But the planet and the moon appear as crescents to us for the same reason. It happens when they are located nearly along our line of sight to the sun, so that their lighted portions – or day sides – are turned mostly out of our view. On the evening Karthik captured Venus, it was just a week away from its greatest brilliancy on September 19, 2023. Why is Venus so bright in our sky, when it’s showing us a crescent phase? Read on to find out.

Venus brightest in the evening sky, February 14, 2025

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Why is Venus so bright?

Jupiter is a bright planet, and Mars is sometimes bright, too. But neither Jupiter nor Mars at their brightest can outshine Venus. And you can compare all three of them in our evening sky now.

So why is Venus so bright?

Our neighboring world – orbiting one step inward from Earth around the sun – is the 3rd-brightest natural object in the sky, after the sun and the moon. It’s currently a brilliant light in the evening sky, shining at magnitude -4.5. Greatest brilliancy for Venus for this 2025 evening apparition will happen on February 14.

Look at the photo above. Venus now appears as a crescent – through telescopes – as seen from Earth. How can a crescent Venus appear brighter to us than the fuller Venus we see at other times?

Albedo = reflectivity

As the planet next inward from Earth in orbit around the sun, Venus is relatively nearby. But its nearness isn’t the only reason Venus is bright. Consider that Mars orbits one step outward from Earth. And Mars waxes and wanes in brightness in our sky over about a two-year cycle. It’s only exceptionally bright around the time Earth passes between Mars and the sun, at the same time Mars is closest to the sun. The last time that happened was in 2018. And the next time will be in 2035.

With Venus, something else is going on. Astronomers use the term albedo to describe how bright a planet is in absolute terms. When sunlight strikes a planet, the planet’s surface absorbs some of the light and reflects the rest.

Albedo is a comparison between how much light strikes an object and how much the objects reflect. And, as you might have guessed, Venus has the highest albedo of any major planet in our solar system.

Reflectivity makes Venus bright

The albedo of Venus is close to 0.7, meaning it reflects about 70% of the sunlight striking it. When the moon is close to full in Earth’s sky, it can look a lot brighter than Venus. But the moon – whose surface is dark volcanic rock – reflects only about 10% of the light that hits it. The moon appears bright to us because it’s close to Earth. It’s only about a light-second away, in contrast to the several light-minutes distance of Venus.

Venus is bright (it has a high albedo) because it’s blanketed by highly reflective clouds. The clouds in the atmosphere of Venus contain droplets of sulfuric acid, as well as acidic crystals suspended in a mixture of gases. Light bounces easily off the smooth surfaces of these spheres and crystals. Sunlight bouncing from these clouds is a big part of why Venus is so bright.

By the way, Venus is the brightest major planet. But it isn’t the most reflective body in our solar system. That honor goes to Enceladus, a moon of Saturn. The little moon’s icy surface reflects some 90% of the sunlight striking it.

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When and why is Venus brightest?

Venus is brightest when two factors combine – the phase of its crescent, plus largest overall size of Venus’ disk – so that the greatest amount of surface area of Venus shows in our sky. Astronomers call this greatest illuminated extent.

Why does it happen? Because Venus orbits the sun inside Earth’s orbit, it sometimes goes between us and the sun. At such times, its lighted hemisphere, or day side, is facing away from us. Then it’s difficult to see Venus at all (though experienced astrophotographers sometimes catch it).

Also, around the time it passes between us and the sun – known as inferior conjunction – we see Venus exhibit phases … like a tiny moon. As Venus draws up behind Earth in orbit – and prepares to “lap” us in the race of the planets – observers on Earth can watch as the phase of Venus wanes. That’s what’s happening now. As Venus gets closer to inferior conjunction, it’ll increase in size as its phase decreases.

When it moves to the other side of the sun, racing ahead of us in orbit again, we see Venus wax in phase. As the crescent Venus waxes in Earth’s sky, the overall size of the disk of Venus gets smaller in our sky, as Venus speeds ahead of us.

Venus at greatest brilliancy soon

Venus will go between us and the sun at 1 UTC on March 23, 2025. Then it’ll be rushing ahead of us in orbit. Its phase will be increasing. But its disk size will be decreasing. Greatest brilliancy happens when we see the greatest illuminated surface area of Venus: a combination of phase size and disk size. Astronomers call this a “greatest illuminated extent” of Venus.

It’s happening now in the west after sunset … and it’s a sight to see! Don’t miss Venus blazing as darkness falls February 14, 2025. And it’ll reach greatest brilliancy again in the morning sky on April 27, 2025.

8 positions of Venus around its orbit, sun in center, with Venus's phases shown as viewed from Earth. — The phases of Venus – and its locations at inferior and superior conjunction – as viewed from Earth. Adapted from an image by NASA/ Chmee2/ Wikimedia Commons (CC BY-SA 3.0).

Read about Venus at greatest brilliancy

The view from above

Circle with sun at center, planets around, and zodiac names on outer edge. — Heliocentric view of solar system, February 2025. Venus is catching up with Earth in our orbits around the sun. Chart via Guy Ottewell’s 2025 Astronomical Calendar. Used with permission.

February finder charts

Chart with a starred dot representing Venus sitting above a small dot representing Saturn which is close to the horizon. — In mid-February, brilliant Venus – at its greatest brilliancy in the evening sky – will lie above the much dimmer Saturn, which will lie close to the horizon. In late February, Saturn will drop below the horizon, lost from view. Chart via EarthSky.

Star chart showing a large starred dot, Venus, above the small dot for Mercury. — Venus will remain a bright light after sunset in late February. It’ll slip away in March and emerge in the morning sky in April. It’ll reach its greatest distance from the morning sun on May 31-June 1, 2025. Mercury will emerge in the bright evening twilight low in the west the last few days of the month and reach its greatest distance from the sun on March 7-8, 2025. Chart via EarthSky.

Sphere with green line for the ecliptic showing the location of the planets Venus, Jupiter, Mars and Saturn in the evening sky on February 14, 2025. — There are actually 4 bright planets in the February evening sky. This view is for mid-month. They will lie along the path the sun travels in daytime (the green line on our chart). Brilliant Venus dazzles in dark skies in the western evening sky, with the steady golden light of Saturn lower on the horizon. High overhead is bright Jupiter, and visible most of the night is the red planet, Mars.

More photos from our community

Composite of crescent moon and crescent Venus. — View at EarthSky Community Photo. | Gwen Forrester of DeKalb County, Tennessee, captured these images on February 3, 2025. Gwen wrote: “Venus has been shining at its brightest recently, accompanied by the waxing crescent moon, as its own crescent phase wanes. Tonight, they were at roughly equal illumination as viewed from Earth.” Thank you, Gwen!

Why is Venus so bright? Bright dot in dark sky with scattered stars including group of stars to right. — View at EarthSky Community Photos. | In April 2023, Venus was a dazzling light in the west after sunset. Charlie Favret of Round Rock, Texas, captured this image on April 11, 2023, and wrote: “A photograph of Venus visiting the 7 Sisters. It is always a pleasure to see the 2 of these in the sky, and even better when they come close together!” Thank you, Charlie!

Thin crescent Venus in a slate blue sky. — View at EarthSky Community Photos. | Steven Bellavia of Mattituck, New York, captured this image on August 13, 2023, at 3:28 p.m. He wrote: “Venus, 0.9% illuminated, at (or very close to) inferior conjunction.” Thank you, Steven!

Line of crescents starting small and getting larger but thinner. — View at EarthSky Community Photos. | Vedant Pandey wrote: “I am Vedant Pandey, a 17-year-old amateur astrophotographer from Varanasi, Uttar Pradesh, India. I photographed Venus since it appeared in the evening sky in February 2023. And here are the phases of Venus, from waning gibbous in February to its crescent phase in August, as seen by my telescope.” Wow! Thank you, Vedant!

Bottom line: You can’t miss dazzling Venus in the west after darkness falls. It’s the 3rd brightest object in the sky, after the sun and moon. But why is Venus so bright?

Read more: Venus before sunrise: Greatest distance May 31-June 1, 2025

Deborah Byrd

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About the Author:

Our Editor-in-Chief Deborah Byrd works to keep all the astronomy balls in the air between EarthSky’s website, YouTube page and social media platforms. She’s the primary editor of our popular daily newsletter and a frequent host of EarthSky livestreams. Deborah created the EarthSky radio series in 1991 and founded EarthSky.org in 1994. Prior to that, she had worked for the University of Texas McDonald Observatory since 1976, and created and produced their Star Date radio series. She has won a galaxy of awards from the broadcasting and science communities, including having an asteroid named 3505 Byrd in her honor. In 2020, she won the Education Prize from the American Astronomical Society, the largest organization of professional astronomers in North America. A science communicator and educator since 1976, Byrd believes in science as a force for good in the world and a vital tool for the 21st century. “Being an EarthSky editor is like hosting a big global party for cool nature-lovers,” she says.

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