• Cheops observes its first exoplanets and is ready for science (ESA)
• CHEOPS space telescope ready for scientific operation (U of Bern)

Astronomers study stars in lots of weird ways, and one of the most surprising ways to even other astronomers is by using defocused images. Yes folks, those of us who have tried to get the best possible measurements of star brightnesses in non-crowded fields will actually unfocus the star light so it spreads out over more pixels. I’ve done this with RR Lyae variable stars using wide field cameras, Adam Reiss has done this with the Hubble Space Telescope and and Cepheid variables… and now the CHEOPS mission does it with everything it looks at as it searches the sky for planets orbiting stars. A few weeks ago, we showed you this early commissioning image of a star without planers. Today, we are happy to share that CHEOPS has observed the star HD 92296 – a star known to be orbited by the planet Kelt-11b – and have observed the transit with a new level of resolution that will allow us to more accurately measure the size of planets and to see smaller worlds than we have been previously been able to see.  

Cheops uses the planetary transit method to see where planets are located – this is the same technique used by Kepler and many other telescopes. As a planet passes in front of its home star, it blocks more and more of the star’s light until it is completely in front of the star. The time the planet takes to go from just taking a tiny bite out of its star’s light to being fully in front of the star’s disk will vary based on how big the star is and how far it is from its Star. By being able to accurately measure the light curve going from nothing by Star, to Star with a planet in front, we will be able to better understand what factors go into planets being dense little super Earths, versus bloated out ice giants…. And it will do a lot of other things.. But that is the research I’m most anxious to see.

While Cheops is still in the check out phase, everything is looking good, and the mission team hopes to transition into routine science operations at the end of the month.