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: "earth"
- Every leap year, we add a compensatory day. In the interim, why is our official time never off by one-quarter or three quarters a day?
- The Earth orbits the sun once every 365.25 days, so every four years we add an extra day to the year (Leap Year). In the interim years we don’t have our “official” time off by any certain amount because each day is only off by 360 min/year. So to have an accurate “official” calendar, all we have to do is add an extra minute to each day, so that every day is 24 hours and 1 min. This number is so insignificant that we don’t calculate it in to our normal calendar, but over time, it will start to add up (1 day every 4 years), so that is why we add the leap day, but do not keep track of the time in the interim.
(Tags: earth) - Have astronauts ever been to ___?
- Astronauts have never been anywhere besides the Earth and Moon (but there have been no Moon trips since 1972). There are plans to return to the Moon (possibly by 2020) and then astronauts may travel to Mars. A trip to the Moon takes about three days, but a one-way trip to Mars will take close to nine months.
(Tags: astronaut earth mars moon) - What is the best place and time to see a meteor shower?
- Meteors, sometimes called falling or shooting stars, are very common in the night sky. As Earth orbits around the Sun, it goes through debris fields, left behind by comets and other celestial objects and events. This debris falls towards the Earth, and burns up as it falls. That's what we see as a meteor. When the Earth goes through a large debris field, we can expect to see more meteors. Sometimes as many as 100 per hour. The Perseid meteor shower, which occurs every year in August, is one of the best meteor showers. To see the most meteors, go outside after midnight, when the sky is its darkest, and watch the show. Meteors will fall from all directions, but often they appear to start at one central point. In the case of the Perseid meteor showers, the meteors all appear to come from the constellation Perseus. If you can, get far away from the city to see the best possible show.
(Tags: earth) - Why is the earth not at 0° solar longitude on March 21 (the vernal equinox, 1st day of spring), but at 180°? Confusingly, the vernal equinox supposedly marks the 0°
- In the diagram (http://ssd.jpl.nasa.gov/?ss_inner), Earth is about at 90 degrees, if you consider the vernal equinox at +X-axis. On March 21, Earth would be at 180 degrees, just like you said. Now, why Earth is not at zero degrees since it is vernal equinox? Because we determine equinoxes according to the Sun’s position, not Earth’s. Put Earth on the Vernal Equinox point (180 degrees). Which direction you see the Sun?
(Tags: earth physics sun) - Will an asteroid hit the Earth in ___?
- Asteroids have hit the Earth in the past and will hit the Earth again someday, but not for a long time.
Astronomers are keeping an eye on a couple objects. One, which will pass near the Earth in the year 2029, has a small (1:45,000) chance of an impact in 2036. The other object, depending on its spin, has either a 0 or a 1:300 chance of impact in the year 2880.
(Tags: asteroid earth)
