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What Passes in Front of the Sun Yet Casts No Shadow?

Relatively few objects pass between Earth and the sun. Most of those that do are much closer to Earth than to the sun, because of the enormous amount of heat the sun produces. The only object that casts a visible shadow on Earth is the moon, due to its size and proximity. Other objects that pass between Earth and the sun are normally too small or too distant to cast a shadow.

Satellites
- Manmade satellites constantly orbit Earth, prisoners of its gravitational field. Many of these satellites pass in front of the sun every day without casting a hint of a shadow on Earth, due to their very small size compared to the sun.
International Space Station
- Passing in front of the sun at the rate of 15 times per day, with an orbital tilt of roughly 52 degrees, the International Space Station is the most expensive structure ever built. This $100 billion project serves as a docking station for space shuttles. The ISS is too small relative to the sun to cast a shadow on Earth.
Planets
- The inner planets -- Venus and Mercury -- sometimes pass between Earth and the sun. These solar transits are relatively uncommon; Mercury transits the sun more often than Venus. As of 2011, the last transit of Venus occurred in the summer of 2004. Although these planets are larger than the moon, their much greater distance means they are too small to cast visible shadows on Earth.
Meteorites
- Meteorites are usually visible only at night; also known as "shooting stars," they typically comprise stone, iron or a combination of both. Meteorites can also occur during the day, and may pass right in front of the sun. However, due to their small size and the brightness of the sun, these meteorites are invisible, and do not cast shadows on Earth.

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