G352.7-0.1: Sweeping Supernovas

Narrator (April Hobart, CXC): Supernovas are the spectacular ends to the lives of many massive stars. They are explosions that produce enormous amounts of energy and can shine as bright as an entire galaxy made up of billions of stars! These events are very important because the remains of the shattered star are hurled into space. This material goes on to form new stars, planets and moons - in fact, both you and I are made of supernova material! As these fields of leftover star material (called supernova remnants) expand, they sweep up all the material they encounter and carry it along with them.

This space photograph shows a 2200-year-old supernova remnant that is sweeping up a remarkable amount of material - enough to make 45 Suns! The blue material in the picture shows the supernova remnant, the space dust is shown in pink. The impressive amount of material swept up by this remnant may be the first clue that something special happened to this star before it exploded. Another clue is the temperature of the material, which is unusually hot and still emitting (sending out) high-energy X-rays. With 2200 years having passed since the supernova explosion, the remaining material has normally cooled much more. Unfortunately, you'll have to watch this space to find out the cause for these oddities, as scientists are still trying to figure it out themselves!

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Narrator (April Hobart, CXC): HD 189733b: An exoplanet in orbit around a star about 63 light years from Earth. It has been nearly two decades since the first exoplanets – that is, planets around stars other than our Sun – were discovered. Now for the first time, X-ray observations have detected an exoplanet passing in front of its parent star. The observations, made by NASA's Chandra X-ray Observatory and the European Space Agency's XMM-Newton Observatory, took advantage of the alignment of a planet and its parent star in HD 189733. This alignment enabled the observatories to observe a dip in X-ray intensity as the planet moved in front of, or transited, the star. This technique is the one used so successfully at optical wavelengths by NASA's Kepler telescope. In earlier studies using optical light, astronomers discovered that the main star in the HD 189733 system had what is known as a "hot Jupiter" around it. This means the planet is about the size of Jupiter, but in very close orbit around its star. The planet – that has been named HD 189733b -- is over 30 times closer to its star than Earth is to the Sun, and goes around the star once every 2.2 days. The new X-ray data suggest that this planet has a larger atmosphere than previously thought. This, in turn, may imply that radiation from the parent star is evaporating the atmosphere of HD 189733b more quickly than expected. The results on HD 189733 demonstrate how we need information from many different telescopes that detect different types of light to get a fuller picture of these mysterious worlds that we are now able to explore.