Have you ever had a specific astronomical question that Google couldn't answer for you? The Planetarium at CSN has a team of expert astronomers and astrophysicists available to answer any question that you may have.
Click to Contact Uswith your astronomy questions.
1. Why is Pluto not considered a planet?
Answer: In 2006, the International Astronomical Union declared that they would no longer consider Pluto a planet because it has not cleared its orbit of debris and other rocky material. Their declaration that this disqualified it from planetary status has received mixed reviews, with many planetary astronomers disagreeing with the IAU statement. In fact, NASA is proposing a counter definition for a planet after their exploration of Pluto with New Horizons. While NASA is trying to go through the proper channels within IAU to change their definition, the definition of a planet is not something that that IAU has unilateral discretion to determine. They have merely declared themselves the arbiters of all space related decisions without having the true authority to do so.
2. When (or where) does space end? (From Ari, age 6)
Answer (by Dr. Stephanie Fiorenza): As of right now, we can see space out to about 15 billion light years. A light year is the distance that light travels in one year. So what that means is that space is really, really big!
It is possible that there is stuff in the universe that's even farther away from the stuff we can see right now. The trouble, though, is that we will probably never get to see these things because space is growing bigger and bigger, and more and more quickly, every moment! So if there are extra things in space that are too far away for us to see, we probably will not ever get to see them because space keeps pushing them farther and farther away from us.
What this means is that we really don't know for sure when space ends. You asked a question that still stumps even the smartest astronomers, Ari! I hope that maybe one day, someone (editor's note: Or even you Ari, when you become a scientist) will come up with a better answer to your question.
Until then, we can do nothing but wait in wonder and awe! :)
3. “My husband and I's first year wedding anniversary is Sunday and for our wedding, I bought us a star! For our one year, I really want to surprise him and take him to a place that can show us our star for the first time. Is there anyway CSN Planetarium can help me make this big surprise happen?” (From Shelby)
Answer (by Nick Juliano, Planetarium Program Manager): Due to the dim nature of 99.99% of stars typically on these types of registries (an apparent magnitude much lower than the human eye can see) in conjunction with the extreme light pollution in Las Vegas (I once lived within 5 miles of NYC and the light pollution here is much worse), it is our policy to not attempt these types of observations. Even with the greatest telescopes, the Las Vegas Valley is not very suitable for observing dim objects.
If you would like to observe this star, my best recommendation would be to buy or rent your own telescope and drive to a dark area to observe it. The nearest certified dark sky site is Great Basin National Park, and that is a great place for observing dim objects. Unfortunately, however, the last telescope rental place in the valley went under several years ago. We at the CSN Planetarium and Observatory lack the location to make these observations, and many other observatories require a research proposal to use their equipment or have it operated for you.
I wish I had better news for you. Good luck with your search, and congratulations on making it past what many say is the most difficult year of marriage. I wish you two many more orbits around our host star.
4. Is there life out there?
Answer: Astronomers have not found any yet.
When astronomers look for extraterrestrial life, they look for single-celled organisms. Single-celled life came around on Earth long before larger life, and that is all we have to work with. So when we search for extraterrestrial life, we search for certain things: similarities between the other object and Earth (liquid water, oxygen, adequate temperature, carbon, etc.), indicators of life’s impact on the object’s geology, or life itself. Nothing has conclusively led to life so far.
There are an estimated 1 septillion stars in the Universe (1,000,000,000,000,000,000,000,000), and over half of the stars we have surveyed have at least one planet around them. That puts our estimated number of planets at a minimum of 500 sextillion (500,000,000,000,000,000,000,000). Statistically, it is literally impossible for Earth to be the only planet with life on it. That being said, it has not been discovered, so it cannot be claimed to exist.
5. How do we discover exoplanets?
Answer: There are three ways:
· Taking an actual image of the planet – this has only been done a handful of times because of the sheer distances between objects
· Observing the planet’s effect on the host star’s movement – planets have gravitational influence on their stars. It is small, but it is there. By observing this gravitational influence in the form of stellar “wobble,” we can determine what objects are orbiting these stars
· Observing the planet’s effect on the host star’s brightness – occasionally, a planet may come in between its host star and Earth, leading to a dip in the star’s brightness. With an orbiting planet, this happens periodically. We can use this information (orbital period and amount of brightness “dip”) to determine a lot about the orbiting object.