Waxing lyrical about exoplanets May 28, 2009Posted by Sarah in new astronomy, science, space.
Tags: astronomy, CoRoT, exoplanets, nature, netherlands
This year we celebrate the 400th anniversary of the first published astronomical observations with a telescope, by Galileo Galilei. Galilei used his telescope to observe the changing phases of Venus and reveal the true configuration of the Solar System. Now, exactly four centuries later, CoRoT observations have shown the changing phases of an extrasolar planet for the first time in optical light.
Blimey, is that a Nature-worthy cheesy quote or what?! And …. that’s exactly what it is*.
In today’s issue of Nature, Leiden astronomers describe how they used a series of observations of star Corot-1 from the CoRoT satellite to map out the phases of the star’s exoplanet CoRoT-1b. An equally (more?) important quote from the end of the paper reads:
We thank the CoRoT team for making the CoRoT data, which forms the basis of this study, publicly available in a high-quality and comprehensible way.
The required precision in the data to be able to carry out these studies is immense (the star’s brightness varies by just 0.01 percent), and a detailed understanding of the behaviour of the instrument and its systematics is absolutely crucial to this work. And not only is it important that the scientists and engineers understand the issues, they also need to relay this information to the end users (the astronomers using the data) and provide data products and analysis programmes that allow the users to correct for them. So the authors rightly give a big hat-tip to the CoRoT team for making it possible.
While demonstrating that we can now map out phases of exoplanets is a neat trick, it does have a broader scientific relevance. Looking at the brightness variation of the planet throughout its phases tells us about the temperature variation between the day- and night-side of the planet, and the way heat from the host star is absorbed or reflected by its gassy envelope and circulates through the planet’s atmosphere.
So it’s not just about watching pretty planets go round: these observations really make a significant contribution to our understanding of how these extrasolar gas planets are formed, behave and evolve.
*Reference (+ quotes): Snellen, De Mooij & Albrecht, Nature vol. 459, pp. 543-545 (read it here) (Nice work guys!)
A press release in Dutch is here with a video.