The strange variable star V838 Monocerotis flared up nearly 5 years ago, and astronomers have been trying to figure out what’s going on ever since. As the light from the flare up propagates out from the star, it illuminates the surrounding cloud of dust. This light reflects off the dust, and we see this echo here on Earth. This latest photograph from the Hubble Space Telescope shows the changes that have happened over the last year. One interesting feature are the whorls and eddies in the dust, which could be caused by powerful magnetic fields.
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Nearly a Thousand Years After the Death of a Star
In 1054 A.D., Chinese astronomers recorded the temporary brightening of a star in the constellation Taurus. Nearly 1000 years later, we look in the same region and see the exploded remnants of a dead star: the Crab Nebula. This composite photograph of the Crab Nebula was made by merging images from Hubble, the Chandra X-Ray Observatory, and the Spitzer Space Telescope. It shows only a hail of high-energy particles and expanding debris cloud that once was a massive star.
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Globular Clusters Sort their Stars
Globular clusters are regions of space where stars are densely packed together – 10,000 times more dense than our local stellar neighbourhood. New evidence from the Hubble Space Telescope has shown that globular clusters will sort out themselves out, hoarding more massive stars in the centre, and pushing the less massive stars out to the edges. Hubble captured images of globular cluster 47 Tucanae for nearly 7 years, allowing astronomers to carefully plot the positions of stars moving in the cluster, and then calculate how close they were to the centre.
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Colliding Spiral Galaxies Captured by Hubble
This Hubble photograph shows two spiral galaxies colliding together. Known as the Antenna Galaxies, aka NGC 4038-4039, these two galaxies started interacting a few hundred million years ago. Thanks to the galactic interaction, perturbed gas clouds in both galaxies collapse into regions of furious star formation (these are the blue regions). Most of these regions will disperse their stars into galactic disks, but some will remain on as super star clusters – similar to the globular star clusters we see in our Milky Way.
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Hubbles Sees Galaxies Under Construction
The latest image released from the Hubble Space Telescope shows a beautiful view of a large galaxy being assembled from a collection of small galaxies. The large galaxy, officially known as MRC 1138-262, but nicknamed the Spider Galaxy, contains dozens of smaller star-forming galaxies. It’s incredibly far away, 10.6 billion years, so we see it as it looked only 3 billion years after the Big Bang. These observations match commonly held theories about how small irregular galaxies merge together to form the larger structures we see today.
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Hubble Examines the Closest Known Extrasolar Planet
The Hubble Space Telescope turned its gaze towards a relatively nearby Jupiter-sized world recently. The planet orbits the Sun-like star Epsilon Eridani, which is located only 10.5 light-years away. This makes the planet so close that it could be directly observable by Hubble, and large ground-based observatories. The best opportunity will come in 2007, when the planet makes its closest approach to its parent star, and the reflected light should make it observable with our best instruments.
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Hubble Finds Distant Extrasolar Planets
The Hubble Space Telescope has identified 16 stars that could have extrasolar planets. The discoveries were made as part of a new Hubble survey, called the Sagittarius Window Eclipsing Extrasolar Planet Search (SWEEPS). This survey looked at 180,000 stars in the central bulge of the Milky Way – 26,000 light years away. The discovery was made using the transit method, where planets dim their parent stars slightly as they pass in front. Further observations will be needed to actually calculate the mass of the transiting planets.
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Hubble Sees the First Bright Galaxies
A new view from the Hubble Space Telescope shows some of the first bright galaxies to emerge in the Universe, appearing around 13 billion years ago, or 900 million years after the Big Bang. Galaxies like these weren’t visible 700 million years after the Big Bang, so smaller galaxies must have merged together quite rapidly for them to get large and bright. The discoveries were made in the Hubble Ultra Deep Field and the Great Observatory Origins Deep Survey Fields.
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Giant Planet or Failed Star?
The Hubble Space Telescope has helped astronomers uncover an object right at the dividing line between stars and planets. The object, known as CHXR 73 B, weighs in at about 12 times the mass of Jupiter, and orbits a larger red dwarf star. The two objects are separated by 200 times the distance of the Earth to the Sun, so astronomers don’t think they both formed out of the same disk of gas and dust.
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Hubble Sees a Rare Transit on Uranus
The Hubble Space Telescope recently captured a very rare event: the transit of its moon Ariel across the surface of Uranus. On Earth we call this an eclipse, when the Moon’s shadow falls upon the surface of our planet. This situation is rare on Uranus; however, because the blue-green planet is tilted over on its side. The Sun, the moons and Uranus only line up once every 42 years. The last time a transit like this could have been seen was 1965, but Earth-based telescopes weren’t powerful enough to image the event at the time.
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