CRI听力: One Year Anniversary of the Launching of Herschel Telescope

European astronomers are celebrating one year of discoveries by the Herschel telescope. Launched on May 14, 2009 from French Guiana, the European built space craft is designed to increase our knowledge about the universe.



Herschel is currently the largest space telescope of its kind when launched. Its mirror, which has a diameter of about 3.5 meters, is bigger than the mirror on the Hubble, which has a diameter of about 2.4 meters.
Unlike NASA's Hubble telescope, which has become famous for its breathtaking images of the heavens, Herschel works in non-visible wavelengths of light, providing scientists with crucial information about planet and star formation.

Annie Zavagno is with the Laboratory of Astrophysics of Marseille. She is a researcher who studies process of star formation. Annie says data collected from the Herschel telescope could help answer questions such as what the universe was made of, how it has evolved and the rate at which it is expanding.

"This is what Herschel gave us, this new view of star formation, in the surrounding of this ionized region. And we are seeing a lot of red objects that are new stars in the way of forming. So they are really new and they were not known before, they were never observed. And we received the first images at the beginning of October and it was really fantastic. We are really happy to have new things and trying to understand because we are making a new step towards our understanding of massive star formation. So the idea is that Herschel can reveal this population of highly embedded stars that are formed in gas and dust cocoon, but that are not visible at optical wavelength for example. So we need Herschel to detect all this population of very young stars."

Goran Pilbratt is one of the lead scientists on the Herschel. He says they are already discovering new stars and Herschel still has two years left of its mission.

"We have done observations with some instruments since the end of last year. And some of the observing modes we have only done the first measurements last week. So we now have good data in all kinds of ways. The actual interpreting of that data only started obviously when we got the data. So in certain respects, like some pictures of star-forming regions, people are already counting how many star which we have never seen before and this type of thing. Whereas in other areas we are just starting now, this is still very early days for Herschel."

Herschel is now making observations for 21 hours everyday before sending them back to Earth in the three remaining hours. To ensure accurate readings of tiny microwaves, equipment aboard Herschel is kept at nearly absolute zero using helium. Pilbratt explains how the telescope works with a model.

"What you can see here is Herschel with the instruments inside the cryostat and with the telescope on the outside. Now, on the ground the cryostat has to be closed because it's a vacuum system. So when you build the satellite you cannot directly align the telescope with what you have inside. You need to do all by measurements and calculations. So exactly one month after the launch, we have opened the cover of the cryostat and for the first time the instruments could see out, could see the sky. And we could verify that the optics was working properly. We saw right away that we could take, if you like, sharp pictures of the sky. And this was a tremendous feeling, that we got it right."

Astronomers will also look for the presence of water in deep space. One year after its launch into a far-flung orbit, scientists are hoping Herschel will to help answer two questions: How did the cosmos begin and are we alone in it

For CRI, I am Li Dong.