Space telescopes designed to observe distant planets need to be powerful, but they also need some method of blocking the light from the parent star, which completely washes out any dimmer objects orbiting it. A strategy from CU-Boulder professor Webster Cash would use a large, daisy-shaped space shield to block the light from the star. A space telescope trailing the shade by thousands of kilometres would then be able to see much fainter objects surrounding the star.
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Four Supernova Remnants by Chandra
These four photographs of supernova remnants in the Large Magellanic Cloud galaxy were taken by the Chandra X-Ray Observatory. The youngest remnant is at the upper left (600 years old), while the oldest is at the bottom left (13,000 years old). These photos show how gas expelled by a dying star is heated to millions of degrees by shockwaves from the supernova explosion.
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Dark Matter Could Be a Galaxy in the Making
European astronomers have discovered a primordial “blob” of dark matter more than 10 billion light-years away. This gigantic object is twice as large as the Milky Way, but it only emits as much energy as 2 billion suns. The discovery was made using the ESO’s Very Large Telescope by surveying the sky in a narrow spectrum of radiation designed to highlight primordial hydrogen atoms. The astronomers think they’re seeing large quantities of gas falling into a clump of dark matter, which could go on to build a large galaxy like the Milky Way.
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Star Forming Regions in Andromeda
Astronomers think that stars form inside collapsing clouds of cold hydrogen gas. This gas is mainly molecular hydrogen; where two hydrogen molecules are bonded together. These clouds are very difficult to see because the Earth’s atmosphere absorbs much of the light that it radiates; however, another gas, carbon monoxide is always present as well, and can be observed easily from Earth. Astronomers from the Max Planck Institute for Radio Astronomy have developed a detailed map of these star forming regions in the Andromeda galaxy.
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Interacting Galaxies Generate a Supernova
When galaxies interact, it’s never a pretty picture. But it can be a source of rebirth and renewal. In this photograph, captured by the European Southern Observatory’s Very Large Telescope, galaxy NGC 5917 (at the top) is tearing apart its nearby neighbour. The tidal forces between galaxies cause huge clouds of gas and dust to compact, creating nurseries of giant, hot stars. These stars live fast and die young as powerful supernovae. Supernova SN2005cf was discovered last year along the bridge connecting the two galaxies.
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Two Dust Disks Around Beta Pictoris
Detailed photographs of nearby star Beta Pictoris by the Hubble Space Telescope show that it’s circled by two disks of dust. Astronomers believe that a planet with the mass of Jupiter is using its gravity to sweep up material from the primary disk. Additional material is attracted to the planet, and is shaped into a second disk. The dust disk was first discovered by ground telescopes in 1984, and then seen by Hubble in 1995.
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Four Planets Shine in the Evening
Linger outside after dark and you’ll be in for a treat next week. Four of our solar system’s bright planets will be arranged in the western skies at the end of June. Jupiter, the brightest “star” in the sky is the easiest to see, but Mercury, Mars and Saturn are there too. The waxing crescent Moon will pass right through the region over several days, pointing the way to these other planets. The best nights to see the planets are on June 27th and 28th, about 45 minutes after sunset.
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Did V838 Monocerotis Eat Three Jupiters?
V838 Monocerotis. You might not remember the name, or even be able to pronounce it, but you’ve seen the pictures. The Hubble Space Telescope first captured images of this amazing star erupting material in 2002, and then photographed it again in subsequent years. A huge cloud of gas and dust, light-years across, is being illuminated before our eyes. But what caused the outburst that set off this explosion? One team of astronomers think we might be looking at the violent deaths of V838 Monocerotis’ planets as they’re consumed.
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Everything’s on the Menu for Supermassive Black Holes
The supermassive black holes that lurk at the heart of most galaxies have enormous appetites. They’ve already consumed millions of times the mass of our own Sun, and they’re not done yet. Everything’s on the menu: mostly gas, dust, planets and stars, but the occasional exotic delicacy gets consumed too. “Compact objects”, such as stellar mass black holes, neutron stars, and white dwarfs occasionally fall into their grasp too. But these objects don’t go with a whimper; they make screams we’ll soon hear across intergalactic space.
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Distant Quasars are Natural Particle Accelerators
An international team of astronomers has gathered new data that helps to explain the origins of quasar particle jets. These are enormous jets, hundreds of thousands of light-years long, emanating from the supermassive black holes at the heart of distant galaxies. They’re mysterious because the energy of particles they emit goes down across the length of the jet. This new theory proposes that the jets are emitting particles through synchrotron radiation; where the environment close to the black hole acts as a natural particle accelerator.
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