My Dark Sky

So, you have sent your name to the Moon…

Now, how about sending your name again to space, this time on board a spacecraft named Kepler that is dedicated to look for Earth-like planet beyond our Solar System?

But this time it is more than just fill in your name and hit submit. To let you know more what Kepler Mission is all about, you have to do some homework and write in 100 words or less why you think the Kepler Mission is important. As usual, you will get a certificate for your participation. Your name and message will then be stored on a DVD and Kepler will carry it into space.

Planets outside our Solar System are called extrasolar planets or exoplanets for short. They are nothing new nowadays; astronomers have found hundreds of them since 1994. However, apart from pulsar planets, these exoplanets are gas giant, not a bit earth-like.

So now the question is: “Are there other planets like our Earth out there?”

Kepler will be able to answer that question. It has the capabilities of detecting Earth-size or even smaller planets in the habitable zone of sun-like stars. The habitable zone is the distance from a star where liquid water can exist on the surface of a planet. If is too near, all the water will vaporised; if is too far, the water will be frozen ice.

Kepler will use a technique known as the transit method to find Earth-like planets. When a planet passes in front of a star, we called that a planet transit. (From Earth, we have Mercury or Venus Transit when they pass in front our Sun). When that happens, the planet will blocks a very very small fraction – only 1/10,000 – of the light from its parent star, causing tiny dips in the brightness of the star. (This is like seeing a drop in brightness of a car’s headlight when a fly moves in front of it!). If we see the dips repeating at regular times, we found a planet!

So as not to miss any of these transits, Kepler will stare at the same star field in the Cygnus-Lyra region for the entire four-year mission.

We can calculate the size of the planet from the change in brightness. The interval between transits will tell us the size of the planet’s orbit and estimate the planet’s temperature. These qualities determine possibilities for life on the planet.

The deadline to submit your name is 1 November 2008. You have about half a year to really think of the importance of this mission.

This “Name in Space” is an activity in association with the International Year of Astronomy 2009 (IYA2009). Both “Name in Space” and IYA2009 are celebrating the 400th anniversary of the achievements of two giants in astronomy; Johannes Kepler‘s publication of his first two laws of planetary motion and the first astronomical use of telescope by Galileo Galilei respectively.

Johannes Kepler, whom this mission was named after, was well known for his laws of planetary motions. He is the first person to recognise that the orbit of planets around the Sun is an ellipse instead of a perfect circle by using the data collected by his mentor, Tycho Brahe, which were the best available before the invention of telescope.

Go and read the mission and send your name in. Imagine years later you can tell your friends: “Kepler spacecraft has just found the first Earth-like planet around a sun-like star capable of supporting life as we know it… and the cool thing is my name is on it!”

Personally, I think this is a good way to let the public know more about the mission and follow its progress.  It feels like we are also part of the mission, a sense of belonging…

~ by thChieh on May 10, 2008.

Posted in Extrasolar Planets
Tags: Kepler Mission