Vela Pulsar Jet: Did Somebody Call the Ghostbusters?

Narrator (April Hobart, CXC): Millions of people around the world believe in ghosts, many of them even claim to have seen one. Well, now you can count yourself among them! This spooky new image shows a massive star in its afterlife. You could say it's a 'ghost star'.

A large star comes to the end of its life when it runs out of fuel. At this point the star's outer layers are blown away in a powerful explosion, and the core collapses in on itself. While the cast off outer layers can create some fascinating and colorful patterns, it's at the core that things get really interesting. This haunting space picture shows the dense, leftover core of a massive star after it has gone through its dramatic end-of-life explosion. While the outer layers are blown away, the core collapses in on itself. Enough material to make a Sun like ours (and then some!) is squashed into an area much smaller than an average city! The core then begins its afterlife as a new type of star.

In this picture the core has been reborn as a 'pulsar'. This is a star that spins around extremely quickly - turning even faster than a helicopter rotor! As it whips round, the pulsars spews out jets of material, can you see one stretching upwards in this picture?

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HD 189733: NASA's Chandra Sees Eclipsing Planet in X-rays for First Time

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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.

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