The Planetarium at UT Arlington
Monday, November 23, 2009
Today's Events
| 2:30 pm | Secret of the Cardboard Rocket |
| Join two children on a magical journey through the Solar System, aided by a talking astronomy book, a cardboard rocket, and a vivid imagination. During this imaginative show, audiences will land on Venus, fly through the rings of Saturn, and discover the secrets of the Solar System. | |
| 5:30 pm | Seven Wonders |
| Turn back the pages of time and witness the ancient wonders of the world as they have not been seen for thousands of years. We will investigate the theories of how these wonders were created and get a glimpse of some of the universe's greatest wonders. | |
Ask the Astronomer Q&A
Tag: "solar system"
- How far away are the stars?
- The closest star system, the Alpha Centauri triple star system, is about 25 trillion (25,000,000,000,000) miles away.
To put that in perspective, it could take us around 30 years to fly to Neptune, the furthest planet in our Solar System. But going at the same speed, it would take around 100,000 years to get to Alpha Centauri.
(Tags: solar system star universe) - If I were to fast-forward into the future, and I was setting up a base on Callisto, what might be the best place to do that? Would somewhere like in the Lofn crater be a good place to put it? If so, what would the area look like? Would I be able to see Jupiter from there? Would the ground feel and look like snow? Would the thin atmosphere carry any sort of sound?
- Callisto is a tidally locked moon which means that the same side is always facing Jupiter (like our Moon).
Unfortunately, the Lofn crater is located on the far side the moon (56˚ S and 23˚W) so your base would never see Jupiter.
The surface of Callisto is covered by ice (water ice), carbon-dioxide and silicates; so it wouldn’t feel like snow, it would feel like hard ice.
The thin atmosphere is so tiny; you can almost consider there is no atmosphere. It is surprising that this tiny moon has an atmosphere; however, it is not stable. The atmosphere is actually running away and is probably being replenished by the surface carbon-dioxide. Such an atmosphere wouldn’t carry any sound.
(Tags: jupiter moon physics solar system) - Is Pluto a planet, or what?
- It's more of an "or what."
When Pluto was discovered, it was thought that it was bigger than the Earth. But it was figured out that Pluto was even smaller than the Earth's Moon. But that's not what did it in.
Starting in 1992 icy objects similar to Pluto were found past Neptune, many in similar orbits to Pluto. It was discovered that there was a second asteroid belt, but made of icy objects, instead of rock. Pluto was still called the smallest planet, and the biggest Kuiper Belt object (Kuiper Belt is named for Dutch-American astronomer : Gerard Kuiper), or KBO.
In 2005 a KBO slightly bigger than Pluto was discovered (now called Eris). In light of the new evidence, the voting members of the naming committee to the International Astronomical Union decided to reclassify Pluto.
(Tags: planet pluto solar system) - What is a "dwarf planet" exactly?
- An unfortunate name.
Many people have an emotional tie to Pluto being a planet. They even have "When I was your age Pluto was still a planet" t-shirts.
The pro- "Pluto is a planet" group was strong, so a compromise was made and "dwarf planet" was born. A planet now has to meet three criteria. First, it is big enough to make itself round (Pluto is), goes around the Sun, and not a planet (Pluto does), but also has to clear its orbit (Pluto does not). A dwarf planet meets the first two conditions but not the third.
A better term would have been "big asteroid."
(Tags: planet pluto solar system)
