NGC 2392: Circus in the Sky

Narrator (April Hobart, CXC): Before the telescope was invented in the 17th century, people thought that the Earth was the center of the Universe. They thought the Sun, the planets and all the stars revolved around us! It was only when we had the technology to peer deeper into space that we realised that not only does the Earth move around the Sun, but the Sun moves around the center of our galaxy, the Milky Way!

In the last 100 years, telescopes have been advancing at an unbelievable rate. Now we have huge radio telescopes that stretch over 50 kilometers, and we even have telescopes that have been launched into space. With these powerful instruments, we can reveal the secret wonders of the Universe that our ancestors never dreamed of!

Take this picture, for example, it shows a planetary nebula, which is the remains of a star that is blowing itself apart. This one is called the "Clownface Nebula", can you see why? It looks like a clowns head, complete with a crazy hairstyle and a big, shiny nose at the center.

This object was first spotted in 1757, but today we are still discovering new details about it. Shown in purple is gas at a temperature over a million degrees. The red, green and blue pattern shows the ejected outer layers of the exploded star. Much more recently, astronomers realized that a very hot pair of stars may live at the center of this gassy cloud, and they are orbiting each other!

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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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