10 hours and 40 minutes. Saturn spins around almost as fast as Jupiter, and shows the same flattening at the poles. Both planets generate such huge centrifugal forces that they are not round, but visibly elliptical. People don’t usually notice this about Saturn, though, because the beautiful system of rings masks the effect. Comments? Questions? Why not mail me at uastronomer@gmail.com
Continue reading →Lunar eclipses are rather more common than Solar Eclipses, even though they have the same cause. When the Earth, Moon and Sun are all positioned in a straight line, the Sun casts a shadow from one of the remaining two objects onto the other. When the Moon is in the middle of the alignment, the Moon’s shadow is cast upon the surface of the Earth, and this gives us a Solar Eclipse. When the Earth is in the middle, it’s … Continue reading →
Mars has two moons: Phobos and Deimos. They’re unusual, compared to other planet’s satellites, because they’re so tiny and orbit so close to the planet. The larger of the two, Phobos, is shaped something like a potato and has a diameter of anything from 20 km to 28 km, depending on how you measure it. It orbits at an altitude of only 9,270 km (compared to Earth’s moon, at over 350,000 km!). Although Deimos orbits at a more reasonable distance … Continue reading →
William Herschel discovered Uranus, and it was completely by accident. In 1781, while using one of his powerful home-made telescopes to survey a region of the sky in the constellation Taurus, he noticed that one star seemed a little larger than the rest. When he checked up on it again a few days later, he found that it had moved which helped confirm that it was actually a new planet. Although he tried to name it after his King, George … Continue reading →
Well now that depends on what you’re measuring from! Let’s try some possibilities: How far is Mars from the Sun? On average: 227.92 million kilometers. But, like everything else in the universe, Mars does not have a perfectly circular orbit. Instead, it moves in an ellipse, sometimes getting as far out as 249.23 million kilometers, and sometimes as close as 206.62 million kilometers. How far is Mars from the Earth? Anything from 54.52 million kilometers up to 401.33 million kilometers. … Continue reading →
