Thursday, July 21, 2011

What's Next For NASA?

The shuttle program officially ended this morning around 6am EDT as Atlantis safely landed back on Earth at Kennedy Space Center. Many people seem to think that the end of the shuttle missions means the end of NASA. This is by no means true! Just because we aren't sending astronauts into space doesn't mean our space program is shutting down! NASA is hard at work developing new technology for future manned space missions, and is planning many robotic missions for the near future. Hubble, Spitzer, and Chandra are still operational and providing astronomers with gorgeous views of space objects. As long as funding continues, JWST will be launched in the upcoming years giving astronomers huge amounts of data to work with. So much is left to be learned about our own solar system and NASA is working on many orbiters, landers, and rovers will be launched to planets and moons in our solar system.

It's sad to see the shuttle program go, but we can still do great science without sending man into space. In fact it's often easier and more beneficial to send a satellite or robot rather than a person into outer space. To learn more about what's next for NASA, check out this excellent article: http://www.nasa.gov/about/whats_next.html

Sunday, July 17, 2011

Comet, Meteor, or Asteroid?

Leonid Meteor Shower

It's a bird! It's a Plane! It's a comet! No wait, a meteor! Or maybe an Asteroid? I know I'm guilty of using these three word synonymously, but each one has a distinct astronomical definition.

Meteoroids are small bodies that range from the size of a grain of sand to the size of a car. Meteoroids that enter Earth's atmosphere are called meteors and when they fall in groups they are called meteor showers. Most meteors break apart completely as they fall through Earth's atmosphere, but those that survive and impact the ground are called meteorites.

Comets are large bodies in the solar system made mostly of ice, dust and small rocks. They range in size from 100m (~300ft) to 100km (~62 miles) and originate from the outer edges of our solar system. Comets are different from other astronomical bodies because they have a visible tail resulting from the solar wind stripping particles off of the comet. About 4,200 different comets have documented in our solar system, and pass by Earth periodically. Comets continue to orbit the sun until they either break apart from solar radiation, crash into the sun, or get ejected from the solar system.

Asteroids are a broad term for pretty much any body in the solar system that's not a planet, moon, meteoroid, or comet. They can be any size or shape and exist in two main areas: the asteroid belt between Mars and Jupiter and the Kuiper belt beyond the orbit of Neptune. Some asteroids orbit closer the to the planets. Astronomers are working on finding and classifying all such asteroids so we can watch for any that might be on a collision course towards Earth!

Image Credit:  Geek.com/gearlog