Chandra X-ray Image & Illustration of HD 189733
Using Chandra and XMM-Newton, astronomers have detected an exoplanet passing in front of its parent star for the first time in X-rays. The artist's illustration shows HD 189733b, a "hot Jupiter" that goes around its star once every 2.2 days. The illustration also reveals the presence of a faint red companion star in the system. The new X-ray observations suggest that HD 189733b has a larger atmosphere than implied by previous optical studies. HD 189733b is the closest hot Jupiter to Earth, making it a prime target for astronomers who want to learn more about this type of exoplanet and the atmosphere around it.

(Credit: X-ray: NASA/CXC/SAO/K.Poppenhaeger et al; Illustration: NASA/CXC/M.Weiss)