How did Galileo realize that the Earth orbits the sun? He realized it when he observed the orbit of Venus. Galileo was born in 1564 in Pisa, Italy. Galileo is famous for saying that the Earth orbits the sun rather than the sun orbits the Earth, but he was not the first person to come […]
#472 How did Galileo realize that the Earth orbits the sun? Read More »
What is the densest material in the universe? Osmium is the densest material on Earth, but the densest material in the universe (that we know of) is that of a neutron star. What is density? Density is the amount of mass that something has in relation to the space that it occupies. For example, a
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Does the Oort cloud exist? Possibly, but there is no way of knowing. It is still just a working theory. The Oort cloud was first theorized by Jan Oort, a Dutch astronomer, in 1950. The idea is that a cloud of icy comets and planetesimals are orbiting the sun at a distance of about 0.03
#433 Does the Oort cloud exist? Read More »
How far will the Voyager probes go? As far as they can get before they are eroded to nothing by space dust. Voyager 1 and 2 were both launched in 1977. As of today, December 4th 2022, Voyager 1 is about 23.7 billion kilometers from the sun and Voyager 2 is about 19.8 billion kilometers
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How thick are Saturn’s rings? The rings of Saturn are incredibly thin. They are only about 10 meters thick. Saturn is a massive planet. It is the second largest planet in the solar system and is 95 times larger than Earth. It is a gas giant, but it could have a solid cure. It has
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How big would the sun be from the surface of Mercury and from the surface of Neptune? From the planet Neptune, the sun would look only slightly brighter than all of the other stars in the sky. You would be able to look at it directly without doing any damage to your eyes. From the
Where does space end? There is no way of knowing, but there is a horizon 46 billion light years away that we can’t see past. There are five different possibilities. That the universe is infinite. That the universe wraps in on itself. That there is no “outside” to the universe. That our universe is embedded
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Where does space start? Technically, it starts at 100 km, but there are five different definitions. Space begins at the Kármán Line, which is 100 kilometers above sea level. There is obviously no sign that says, “Welcome to Space!”, so any line that shows the boundary of space has to be arbitrary. The reasoning behind
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How big was the asteroid that killed the dinosaurs? It was probably 10 km across, but it could have been anywhere between 10 and 17 km. The asteroid that killed the dinosaurs hit Earth about 66 million years ago. Apparently, according to research, it was 66,043,000 (±11,000 years). The asteroid came down in the Yucatan
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How does a rocket engine work? Rocket engines work because of Newton’s third law of motion. Newton’s third law of motion states “to every action there is always opposed an equal reaction; or, the mutual actions of two bodies upon each other are always equal, and directed to contrary parts.” Or, in other words, for
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