By mistake – that's why the moon is not a planet

China has collected rock samples from the far side of the moon for the first time. Scientists hope that these samples will provide new knowledge about the formation of the Moon and Earth.

China's moon mission was also the topic of “10vor10” this week. Wassiliki Gotziomitros (46) made a small mistake.

The news anchor led the program as confidently as ever. However, she relented: “China collects samples from the back of the planet for the first time.”

that's wrong. “The moon is not a planet, but rather a natural satellite that revolves around the Earth,” explains the doctor. Florian Kiehl of ETH Zurich told Nau.ch. Kiehl also works at the University of Zurich at the Institute for Astrophysics, and in the past for seven years at NASA.

What distinguishes a planet from a satellite? “The moon is a celestial body orbiting a planet. On the other hand, a planet orbits the sun or a star, has a roughly circular shape and its orbit is clear of other objects.

This means: If the Moon orbited the Sun instead of the Earth, it would be considered a dwarf planet.

At the request of Nau.ch, the SRF clarifies that the error in the “10vor10” version was not noticed. There were no negative reactions about it either.

Space researcher Florian Kiel doesn't think the slip of the tongue is a big deal: “Errors are human and confusion can arise quickly in the 'heat of battle'. I'm sure those responsible at the SRF understand the difference.”

It is not a common misconception that the moon is a planet, according to researcher Dr. Florian Keil. However, other errors related to the universe will be more persistent.

Expert: “Many people say that objects or astronauts become weightless once they are in space. This is not the case.” The International Space Station, which orbits the Earth at an altitude of 400 km, will have 90% of Earth’s gravity.

Keel: “If you were released from this height, you would fall to the ground like a stone. The reason this does not happen is that the International Space Station flies around the Earth very quickly. Therefore it is always in a state of “free fall”.

This would create “weightlessness” on the space station, says Florian Kihl. If the ISS slows down, the station will fall down.

Another point that few people know: there is no sound in the vacuum of space. Sound waves need a medium to propagate. Since there are (almost) no atoms or molecules that can collide with each other in a vacuum, space is completely silent. The expert: “Think about this when you hear loud explosions in space in the next science fiction movie… a common mistake in Hollywood.”

Additionally, many people don't realize how close space is. According to the international definition, it begins at an altitude of 100 km. “This roughly corresponds to the distance from Zurich to Bern. With a rocket you can reach space in just a few minutes.”