Astronomy

NASA’s Hubble Space Telescope is back in business, ready to uncover new worlds, peer ever deeper into space, and even map the invisible backbone of the universe. The first snapshots from the refurbished Hubble showcase the 19-year-old telescope’s new vision. Topping the list of exciting new views are colorful multi-wavelength pictures of far-flung galaxies, a densely packed star cluster, an eerie “pillar of creation,” and a “butterfly” nebula. With its new imaging camera, Hubble can view galaxies, star clusters, and other objects across a wide swath of the electromagnetic spectrum, from ultraviolet to near-infrared light. A new spectrograph slices across billions of light-years to map the filamentary structure of the universe and trace the distribution of elements that are fundamental to life. The telescope’s new instruments also are more sensitive to light and can observe in ways that are significantly more efficient and require less observing time than previous generations of Hubble instruments. NASA astronauts installed the new instruments during the space shuttle servicing mission in May 2009. Besides adding the instruments, the astronauts also completed a dizzying list of other chores that included performing unprecedented repairs on two other science instruments.

Now that Hubble has reopened for business, it will tackle a whole range of observations. Looking closer to Earth, such observations will include taking a census of the population of Kuiper Belt objects residing at the fringe of our solar system, witnessing the birth of planets around other stars, and probing the composition and structure of the atmospheres of other worlds. Peering much farther away, astronomers have ambitious plans to use Hubble to make the deepest-ever portrait of the universe in near-infrared light. The resulting picture may reveal never-before-seen infant galaxies that existed when the universe was less than 500 million years old. Hubble also is now significantly more well-equipped to probe and further characterize the behavior of dark energy, a mysterious and little-understood repulsive force that is pushing the universe apart at an ever-faster rate.

Here you can find new pictures taken by “refurbished” Hubble. Enjoy.

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Scientists have found evidence that another object has bombarded Jupiter, exactly 15 years after the first impacts by the comet Shoemaker-Levy 9 — a comet that had been seen to break into many pieces before the pieces hit Jupiter in 1994.

First discovered by Australian amateur astronomer Anthony Wesley on July 19, the Pacific Ocean-sized black spot is likely the result of a collision with an asteroid or comet. Following this, scientists at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California, using the Infrared Telescope Facility at the summit of Mauna Kea, Hawaii, gathered evidence indicating an impact.

The infrared images show the likely impact point was near the south-polar region, with a visibly dark “scar” and bright upwelling particles in the upper atmosphere detected in near-infrared wavelengths, and a warming of the upper troposphere with possible extra emission from ammonia gas detected at mid-infrared wavelengths.

This image was taken at 1.65 microns, a wavelength sensitive to sunlight reflected from high in Jupiter’s atmosphere, and it shows both the bright center of the scar (bottom left) and the debris to its northwest (upper left).

New pictures of Jupiter and its recent impact site keep pouring in, showing the rapidly growing atmospheric aftermath in increasingly greater detail.

Later in the week, the Hubble Space Telescope’s newest camera captured the sharpest visible-light picture to date of Jupiter’s latest feature. Not only did the image provide greater detail on the impact itself, but also it proved astronauts successfully serviced the telescope in May.

Operators of the Keck and Hubble telescopes originally scheduled other work for the week but decided to postpone their plans to better study the unfolding events on Jupiter. They join a multitude of amateur and professional astronomers across the world now training their eyepieces on the planet’s constantly changing spot.

NASA scientists estimate the colliding object was several hundreds of yards across and the force of its impact to have been thousands of times greater than the explosion in 1908 over the Siberian Tunguska River Valley.

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The longest total solar eclipse during the 21st century, not to be surpassed until June 2132 has took place on 22 July 2009. It lasted a maximum of 6 minutes and 39 seconds off the coast of Southeast Asia,causing tourist interest in eastern China, Japan, India and Nepal. This was the second in the series of three eclipses in a one-month period, with two minor penumbral lunar eclipses, first on July 7 and last on August 6.

A partial eclipse was seen within the broad path of the Moon’s penumbra, including most of Southeast Asia (all of India and China) and north-eastern Oceania.

The total eclipse was visible from a narrow corridor through northern Maldives, northern India, eastern Nepal, northern Bangladesh, Bhutan, northern Philippines, the northern tip of Myanmar, central China and the Pacific Ocean, including the Ryukyu Islands, Marshall Islands and Kiribati.

Totality was visible in many large cities, including Surat, Vadodara, Bhopal, Varanasi, Patna, Gaya, Dinajpur, Siliguri, Guwahati, Tawang in India and Chengdu, Nanchong, Chongqing, Yichang, Jingzhou, Wuhan, Huanggang, Hefei, Hangzhou, Wuxi, Huzhou, Suzhou, Jiaxing, Ningbo, Shanghai, as well as over the Three Gorges Dam in China. According to NASA, the Japanese island Kitaio Jima was predicted to have the best viewing conditions featuring both longer viewing time (being the closest point of land to the point of greatest eclipse) and lower cloud cover statistics than all of continental Asia.

Picture: Total eclipse as seen on Varanasi, India [credit: wikipedia]

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Venus is the sixth largest planet. Its orbit is almost circular and varies only 1%. It has the most perfect orbit of all of the planets. It is the second planet from the sun. Also, Venus’ rotation is the slowest of all planets. It takes 243 Earth days for it to rotate.

The center of Venus is very similar to that of Earth. Its iron core is approximately 3000 kilometers in radius. The rest of the planet is made up of molten rock mantle. There is no tectonic plates as Earth does. There is evidence of recent volcanic activity on Venus.

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A report published in the scientific journal Nature of results from the Cassini probe indicates the discovery of the existence of liquid water on Saturn’s moon Enceladus, and with it the possibility of extraterrestrial life.

Analysis of ice particles once thought to be emitted by geysers from the moon revealed the presence of sodium salt in the ice. As on Earth, the most plausible explanation of the presence of salt water is the prolonged contact of liquid water with mineral bearing rocks.

The currently understood scientific model of how life occurs requires the presence of three elements: the existence of complex organic molecules, liquid water and a source of energy. All three appear to be present on Enceladus.

The possibility of discovering a global ocean on the moon has receded, and has been replaced by the idea of large subterranean caverns with large pools or lakes of water, created by tidal forces acting upon Enceladus, and it is from these mist filled caverns that the water evaporates into the atmosphere in a steady jet. However, until further flybys and missions can be carried out other mechanisms for the presence of salt water ice cannot yet be dismissed.

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When the crew of the Space Shuttle Atlantis released the Hubble Space Telescope to return to orbit, concluding the final astronaut mission to upgrade and repair Hubble, astronomy fans around the world rejoiced. Hubble, renewed and equipped with new cameras, would now return to its work of revealing the universe.

But after the furor and high-profile feats of a servicing mission, Hubble sinks into silence. This time, a three-month hiatus will take place between the mission and any new images.

The quiet belies the intense activity going on behind the scenes. Engineers and scientists are conducting a slow, painstaking process of Servicing Mission Observatory Verification (SMOV) — bringing the telescope to full functionality, making the adjustments and gathering the information that will allow them to provide the best, clearest, cleanest images. Once that’s accomplished, Hubble will begin taking its Early Release Observations (EROs), images intended to demonstrate the telescope’s new technology. Read full entry »

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Hubble Space Telescope has been launched by the shuttle Discovery in 1990. It released into an orbit 304 nautical miles above the Earth. Since then it’s circled Earth more than 97,000 times and provided more than 4,000 astronomers access to the stars not possible from inside Earth’s atmosphere. Hubble has helped answer some of science’s key questions and provided images that have awed and inspired the world.

Since then, four shuttle missions has been flying to the telescope, to replacing and repairing failed and faulty components and added new and improved cameras and scientific equipment. Now the fifth and also last mission has done the same again. Atlantis spacecraft’s crew - launched on May 11 - has been successfully installing several new scientific instruments.

The Cosmic Origins Spectrograph will observe the light put out by extremely faint, far-away quasars and see how that light changes as it passes through the intervening gas between distant galaxies. In this way scientists will learn what that gas is made of, how it’s changed over time and how it affects the galaxies around it. New Wide Field Camera 3 (WFC3) will allow Hubble to take large-scale, extremely clear and detailed pictures over a very wide range of colors. At ultraviolet and infrared wavelengths the WFC3 represents a dramatic improvement in capability over all previous Hubble cameras. It is also a very capable visible light camera, though by design not quite as capable at visible wavelengths as Hubble’s Advanced Camera for Surveys (ACS). The WFC3 and ACS are designed to work together in a complementary fashion.

The new camera and spectrograph are designed to complement the scientific instruments already on the telescope – specifically the Advanced Camera for Surveys and the Space Telescope Imaging Spectrograph. But pieces of those instruments have failed in past years – not the entire instrument, but specific pieces inside of them. The crew will replace only the pieces that have failed.

NASA hopes the final service will keep the telescope operate for another five to 10 years, before it is steered to reenter earth’s atmosphere and plunges into the ocean. A sad ending actually, for such a precious and one of the greatest scientific instruments ever built.

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Over the past 19 years Hubble has taken dozens of exotic pictures of galaxies going “bump in the night” as they collide with each other and have a variety of close encounters of the galactic kind. Just when you thought these interactions couldn’t look any stranger, this image of a trio of galaxies, called Arp 194, looks as if of the galaxies has sprung a leak. The bright blue streamer is really a stretched spiral arm full of newborn blue stars. This typically happens when two galaxies interact and gravitationally tug at each other gravitationally.

This interacting group contains several galaxies, along with a “cosmic fountain” of stars, gas and dust that stretches over 100,000 light years. Resembling a pair of owl’s eyes, the two nuclei of the colliding galaxies can be seen in the process of merging at the upper left. The bizarre blue bridge of material extending out from the northern component looks as if it connects to a third galaxy but in reality the galaxy is in the background and not connected at all. The blue “fountain” is the most striking feature of this galaxy troupe and it contains complexes of super star clusters that may have as many as dozens of individual young star clusters in them.

Resembling a pair of owl’s eyes, the two nuclei of the colliding galaxies can be seen in the process of merging at the upper left. The bizarre blue bridge of material extending out from the northern component looks as if it connects to a third galaxy but in reality this galaxy is in the background and not connected at all. Hubble’s sharp view allows astronomers to try and sort out visually which are the foreground and background objects when galaxies, superficially, appear to overlap.

The blue “fountain” is the most striking feature of this galaxy troupe and it contains complexes of super star clusters that may have as many as dozens of individual young star clusters in them. It formed as a result of the interactions among the galaxies in the northern component of Arp 194. The gravitational forces involved in a galaxy interaction can enhance the star formation rate and give rise to brilliant bursts of star formation in merging systems.

Arp 194, located in the constellation of Cepheus, resides approximately 600 million light-years away from Earth. Arp 194 is one of thousands of interacting and merging galaxies known in our nearby Universe. These observations were taken in January 2009 with the Wide Field Planetary Camera 2. Blue, green and red filters were composited together to form this rather picturesque image of a galaxy interaction.

This picture was issued to celebrate the 19th anniversary of the launch of the Hubble Space Telescope. Since its launch aboard the space shuttle Discovery in 1990, Hubble has made more than 880.000 observations and snapped over 570.000 images of 29.000 celestial objects over the past 19 years.

Image Credits: NASA, ESA and the Hubble Heritage Team (STScI/AURA)

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The most crowded collision of galaxy clusters has been identified by combining information from three different telescopes. This result gives scientists a chance to learn what happens when some of the largest objects in the universe go at each other in a cosmic free-for-all. Using data from NASA’s Chandra X-ray Observatory, Hubble Space Telescope, and the Keck Observatory in Hawaii, astronomers were able to determine the three-dimensional geometry and motion in the system MACS J0717.5+3745 (or MACS J0717, for short), located about 5.4 billion light-years from Earth.

This composite image showing MACS J0717, where four separate galaxy clusters have been involved in a collision — the first time such a phenomenon has been documented. Hot gas is shown in an image from NASA’s Chandra X-ray Observatory, and galaxies are shown in an optical image from NASA’s Hubble Space Telescope. The hot gas is color-coded to show temperature, where the coolest gas is reddish purple, the hottest gas is blue, and the temperatures in between are purple.

The repeated collisions in MACS J0717 are caused by a 13-million-light-year-long stream of galaxies, gas, and dark matter — known as a filament — pouring into a region already full of matter. A collision between the gas in two or more clusters causes the hot gas to slow down. However, the massive and compact galaxies do not slow down as much as the gas does, and so move ahead of it. Therefore, the speed and direction of each cluster’s motion — perpendicular to the line of sight — can be estimated by studying the offset between the average position of the galaxies and the peak in the hot gas.

MACS J0717 is located about 5.4 billion light-years from Earth. It is one of the most complex galaxy clusters ever seen. Other well-known clusters, like the Bullet Cluster and MACS J0025.4-1222, involve the collision of only two galaxy clusters and show much simpler geometry.

Image credits: NASA, ESA, CXC, C. Ma, H. Ebeling, and E. Barrett (University of Hawaii/IfA), et al., and STScI

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NASA recently publish first images (or “first lights”, as astronomer says) taken from Kepler spacecraft. It is the mission specifically designed to survey our region of the Milky Way galaxy to discover hundreds of Earth-size and smaller planets in or near the habitable zone and determine the fraction of the hundreds of billions of stars in our galaxy that might have such planets.

These pictures are taken just at the day after cover release. It shows a glittering array of millions of stars stretching across the field of view. Also in the field are star clusters, background galaxies beyond the Milky Way and three stars that are known to have “hot Jupiters” orbiting them. Kepler will observe these stars for an early confirmation of the planet detection capability of the analysis software to be used on all of Kepler’s target stars.

Analysis of the images taken over the past several days shows that the telescope is well within the focus requirements levied on the instrument. The data were taken under stable temperature conditions and with the spacecraft in the highest pointing stability mode, called fine point. Engineers are now working with the science team to determine whether optimizing the focus further would provide a significant improvement in science return. If so, the 1.4-meter (55-inch) primary mirror assembly will be adjusted to fine-tune the alignment.

Launched on March 6, 2009, the scientific goal of the Kepler Mission is to explore the structure and diversity of planetary systems, with a special emphasis on the detection of Earth-size planets. It will survey the extended solar neighborhood to detect and characterize hundreds of terrestrial and larger planets in or near the “habitable zone,” defined by scientists as the distance from a star where liquid water can exist on a planet’s surface. The results will yield a broad understanding of planetary formation, the frequency of formation, the structure of individual planetary systems, and the generic characteristics of stars with terrestrial planets.

Some of the first images from Kepler can be found here.

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