13 September, 2009

Sunday Sensational Science

Hubble Rejuvenated

Thanks to Darksyde at Daily Kos, thee shall have gorgeous new Hubble Space Telescope images to drool over. Most of you know that Hubble got an upgrade back in May. The cameras are now calibrated, and Hubble's back to providing breathtaking images and scientific insight into the cosmos that was unimaginable before it launched.

Even before calibration was finished, Hubble ended up snapping away. It's not every day that you get a chance to capture the impact of an asteroid on Jupiter - the last time was comet Shoemaker-Levy 9 a decade and a half ago. What's an astronomer to do - keep fiddling the instruments until all is perfection, or say bugger perfection and capture something really incredible?

We all know the answer to that one:

24-Jul-2009: The checkout and calibration of the NASA/ESA Hubble Space Telescope has been interrupted to aim the recently refurbished observatory at a new expanding spot on the giant planet Jupiter. The spot, caused by the impact of a comet or an asteroid, is changing from day to day in the planet’s cloud tops.

For the past several days the world's largest telescopes have been trained on Jupiter. Not to miss the potentially new science in the unfolding drama 580 million kilometres away, Matt Mountain, director of the Space Telescope Science Institute in Baltimore, Maryland, allocated discretionary time to a team of astronomers led by Heidi Hammel of the Space Science Institute in Boulder, Colorado.

The Hubble picture, taken on 23 July, is the sharpest visible-light picture taken of the feature and is Hubble's first science observation following its repair and upgrade in May. Observations were taken with Hubble's new camera, the Wide Field Camera 3 (WFC3).


"Since we believe this magnitude of impact is rare, we are very fortunate to see it with Hubble", added Amy Simon-Miller of NASA's Goddard Space Flight Center. She explained that the details seen in the Hubble view show a lumpiness to the debris plume caused by turbulence in Jupiter's atmosphere. The spot is presently about twice the length of the whole of Europe.

Simon-Miller estimated that the diameter of the object that slammed into Jupiter was at least twice the size of several football fields. The force of the explosion on Jupiter was thousands of times more powerful than the suspected comet or asteroid that exploded over the Tunguska River Valley in Siberia in June 1908.

So there was that excitement. After that, calibration continued, and I think you'll all agree the results were worth a spacewalk for:

The NASA/ESA Hubble Space Telescope's newly repaired Advanced Camera for Surveys (ACS) has peered across almost five billion light-years to resolve intricate details in the galaxy cluster Abell 370. Abell 370 is one of the very first galaxy clusters where astronomers observed the phenomenon of gravitational lensing, the warping of space-time by the cluster’s gravitational field that distorts the light from galaxies lying far behind it. This is manifested as arcs and streaks in the picture, which are the stretched images of background galaxies.

These two images of a huge pillar of star birth demonstrate how observations taken in visible and in infrared light by the NASA/ESA Hubble Space Telescope reveal dramatically different and complementary views of an object.

The pictures demonstrate one example of the broad wavelength range of the new Wide Field Camera 3 (WFC3) aboard the Hubble telescope, extending from ultraviolet to visible to infrared light.

This celestial object looks like a delicate butterfly. But it is far from serene.

What resemble dainty butterfly wings are actually roiling cauldrons of gas heated to nearly 20 000 degrees Celsius. The gas is tearing across space at more than 950 000 kilometres per hour — fast enough to travel from Earth to the Moon in 24 minutes!

A dying star that was once about five times the mass of the Sun is at the centre of this fury. It has ejected its envelope of gases and is now unleashing a stream of ultraviolet radiation that is making the cast-off material glow. This object is an example of a planetary nebula, so-named because many of them have a round appearance resembling that of a planet when viewed through a small telescope.

The Wide Field Camera 3 (WFC3), a new camera aboard the NASA/ESA Hubble Space Telescope, snapped this image of the planetary nebula, catalogued as NGC 6302, but more popularly called the Bug Nebula or the Butterfly Nebula.

A clash among members of a famous galaxy quintet reveals an assortment of stars across a wide colour range, from young, blue stars to aging, red stars.

This portrait of Stephan's Quintet, also known as the Hickson Compact Group 92, was taken by the new Wide Field Camera 3 (WFC3) aboard the NASA/ESA Hubble Space Telescope. Stephan's Quintet, as the name implies, is a group of five galaxies. The name, however, is a bit of a misnomer. Studies have shown that group member NGC 7320, at upper left, is actually a foreground galaxy that is about seven times closer to Earth than the rest of the group.

Using a distant quasar as a cosmic flashlight, a new instrument aboard the NASA/ESA Hubble Space Telescope has begun probing the invisible, skeletal structure of the Universe.

Called the cosmic web, it is the diffuse, faint gas located in the space between galaxies. More than half of all normal matter resides outside of galaxies. By observing the cosmic web, astronomers can probe the raw materials from which galaxies form, and determine how this gas was assembled into the complex structures of the present-day Universe.

Using the light from the quasar PKS 0405-123, located 7.8 billion light-years away, the newly installed Cosmic Origins Spectrograph (COS) on Hubble probed a string of gas clouds residing along the light path at different distances. Quasars are the bright cores of active galaxies and are powered by supermassive black holes. Thousands of quasars have been observed, all at extreme distances from our Milky Way galaxy. The most luminous quasars radiate at a rate equivalent to a trillion Suns.

The COS spectrum shown here reveals the absorption lines of elements that make up the intervening gas clouds traversed by the quasar's light. COS detected three to five times more lower-density filaments of hydrogen in the cosmic web than were seen in previous observations along this line of sight. The instrument also detected evidence of glowing oxygen and nitrogen that predominantly trace strong shocks in the filamentary cosmic web. These shocks are produced by gravitational interactions between intergalactic clouds of gas falling onto filaments in the web and by the fast outflow of material from star-forming galaxies.

Rings of brilliant blue stars encircle the bright, active core of this spiral galaxy, whose monster black hole is blasting material into space at over 14 million kilometres per hour. Viewed nearly face-on, the galaxy, called Markarian 817, shows intense star-forming regions and dark bands of interstellar dust along its spiral arms. Observations by the new Cosmic Origins Spectrograph (COS) aboard the NASA/ESA Hubble Space Telescope captured the powerful outflow of material from this galaxy.

The signature balloon-shaped clouds of gas blown from a pair of massive stars called Eta Carinae have tantalised astronomers for decades. Eta Carinae has a volatile temperament, and has been prone to violent outbursts over the past 200 years.

Observations by the newly repaired Space Telescope Imaging Spectrograph (STIS) aboard NASA's Hubble Space Telescope reveal a stream of charged particles from a massive stellar wind and some of the chemical elements that were ejected in the eruption seen in the middle of the nineteenth century.

STIS resolved the chemical information along a narrow section of one of the giant lobes of ejected material. In the resulting spectrum, iron and nitrogen define the outer material cast off in the nineteenth century from Eta Carinae. STIS also reveals the interior material being carried away by the ongoing wind from Eta Car A, the primary star. The amount of mass being carried away by the wind is the equivalent of one Sun every thousand years.
Plenty more where that comes from, my darlings, including videos. Enjoy!

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