Venus and Mercury are Venus and Mercury, and because they have no moons, they never undergo any form of eclipse. Even if Venus had a moon, observers on its blistering hot surface would never see an eclipse firsthand since the planet is continually engulfed by heavy clouds.
However, because Venus is so close to the Earth, it does affect our environment in significant ways. Electricity usage increases during periods of intense solar activity when many more electrons are ejected from the Sun, causing problems for satellites and astronauts on Earth. The increased electrical current can also cause radio interference with global communications systems.
The most notable aspect of Venus as it affects us here on Earth is that it causes severe weather. Solar flares are huge bursts of radiation that can damage or destroy satellites and other spacecraft, and they often include particles that reach Earth. If these particles were not deflected away from our planet by the magnetic fields surrounding it, we would be hit by a constant stream of cosmic rays. These collisions would produce more extreme weather patterns such as stronger winds and storms at high latitudes.
Because Venus always looks like it is within an hour of eclipses starting and ending, this has caused some cultures to believe that it is responsible for bringing about the events it resembles. For example, some people think that Venus' presence in the evening sky every night before full moons is why farmers need to stop working on Sundays!
The planet must have a moon in order to experience an eclipse. The nature (total or partial) and length of eclipses vary based on how large the satellite and the Sun look in the sky of a specific planet. Because Mercury and Venus do not have moons, eclipses are not possible.
Eclipses can only happen with bodies that have at least half-lit faces - planets, satellites, comets, and meteoroids. A total lunar eclipse happens when the Earth is completely blocked out by the Moon. Only the far side of the Moon is visible from Earth during a total lunar eclipse, so it appears as if the entire surface is darkening at once. A partial lunar eclipse shows some of the Moon's face illuminated while others are still hidden beneath the Earth's shadow. Eclipses can also be seen from space using instruments such as the Solar Eclipse Explorer (SEE), which was sent into orbit around the Moon during the 1970s Apollo 14 mission.
Lunar eclipses can only happen within certain times of the year and for only certain parts of the world. If you're living somewhere that has a chance of seeing a total lunar eclipse, start making plans now!
The next total lunar eclipse will be on April 20th, 2024. It will be visible from pretty much everywhere on Earth except North America.
A transit of Venus is even more unusual than solar or lunar eclipses, occurring just approximately twice per century! (Of course, it's not as bizarre as a total solar eclipse or as gory as a total lunar eclipse!) Why do lunar eclipses occur more frequently than solar eclipses? It's because the Moon is smaller than the Earth, and so it passes through more of its shadow. Solar eclipses can only happen on the Earth, not the Moon!
Lunar eclipses are visible on half of Earth, while solar eclipses are seen by half of Earth's surface area. Because of this, many people live in regions where they can see lunar eclipses but not solar ones.
It's also worth mentioning that a transit of Venus occurs when the planet Venus passes directly between the Sun and Earth. This happens about once every 584 days, but since our understanding of astronomy has improved, so have our estimates of how long Venus takes to orbit the Sun. Now we know that it takes around 246 million years! So there you have it, a transit of Venus is when Venus blocks out part of the Sun!
Another thing to note is that a transit of Venus doesn't need to be visible from everywhere on Earth to be noticed by scientists. They study trends over time, so even if you aren't able to see all of the stars during a transit, you'll still be contributing data to science!
Because the Earth is significantly larger than the Moon, its shadow will never be tiny enough to leave a ring. The moon, on the other hand, experiences complete eclipses. A partial lunar eclipse happens when the Moon passes through only a portion of the Earth's umbra or penumbra. Because the center of the moon is always illuminated by the sun, this causes some shadows to fall on the surface.
Lunar eclipses can be either total or partial. If a total lunar eclipse occurs, then all of the moon is within the path of the Earth's shadow. Only the far side of the Moon is in darkness; the opposite side is brightened by the Sun. A partial lunar eclipse happens when only part of the Moon is covered by the Earth's shadow. In this case, only half of it is dark. The other half remains exposed to the sunlit sky.
Lunar eclipses are visible on half of Earth. Where it is night, the eclipse will be visible as a red-colored Moon. Where it is the day, the eclipse won't be visible. During a total lunar eclipse, the Earth's atmosphere refracts light from the Sun that reaches and enters its shadow to create a reddish hue on Earth's moon. The color varies depending on how much dust or clouds are present in Earth's atmosphere at the time of the eclipse.
The Moon completely obscures the disk of the Sun during a total eclipse. Total solar eclipses are extremely rare in any given area because totality occurs only in a limited path on the Earth's surface traced by the Moon's full shadow, or umbra. Regions within this path will experience a total eclipse once every few years on average. Further out distances are far less likely to experience a total eclipse than nearby regions.
Total eclipses occur near either the beginning or end of an eclipse season. At most times of year, especially in temperate zones, the Sun is not fully covered by clouds or fog, so no part of its surface can see a total eclipse at any one time. However many people enjoy viewing the eclipse from locations where it is obscured by clouds or darkness before or after totality has ended.
A total lunar eclipse happens when the Moon is completely inside the Earth's shadow. Because all direct sunlight is blocked from directly reaching the Moon, only light from the Sun as refracted through Earth's atmosphere reaches it. The result is a darkening of the lunar surface and a visible reddish hue caused by sunlight passing through Earth's atmosphere reaching our eyes on opposite sides of the planet.