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HD 189733b, the first exoplanet caught passing in front of its parent star in X-rays. NASA's Chandra X-ray Observatory and the ESA's XMM Newton Observatory have been used to observe a dip in X-ray intensity as HD 189733b transits its parent star. The main figure is an artist's impression showing the HD 189733 system, containing a Sun-like star orbited by HD 189733b, an exoplanet about the size of Jupiter . This "hot Jupiter" is over 30 times closer to its star than Earth is to the Sun and goes around the star once every 2.2 days, as determined from previous observations. Also in the illustration is a faint red companion star, which was detected for the first time in X-rays with these observations. This star orbits the main star about once every 3, 200 years. The inset contains the Chandra image of HD 189733. The source in the middle is the main star and the source in the lower right is the faint companion star. The source at the bottom of the image is a background object not contained in the HD 189733 system. Release date July 29, 2013.
