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Would be so sweet if LISA – LISA (NASA), LISA (ESA) – gets launched on time (2012) and is successful.
Jupiter was visible last evening, definitely couldn’t mistake it for a star…it was very bright
Seems they’ve found something on Mars, webcast of newsconference…
Signs of Water On Mars :aliensmile:
cosmic life imitates art : or so goes today’s headline + gorgeous front page starry pic in the guardian …
you can check it out here
"rambleon" wrote:cosmic life imitates art : or so goes today’s headline + gorgeous front page starry pic in the guardian …you can check it out here
[img]http://www.ibiblio.org/wm/paint/auth/gogh/starry-night/gogh.starry-night.small.jpg[/img]
[img]http://image.guardian.co.uk/sys-images/Guardian/Pix/pictures/2004/03/05/hubble.jpg[/img]
Click on the pix to enlarge….
"dB stands for den Buck" wrote:"The galaxy, dubbed Abell 1835 IR1916, is 13.23 billion light-years from Earth"
Holy Sh*t!!!! That is so far away!!!!
"The universe, thought to have begun with the Big Bang some 13.7 billion years ago, would have been a mere 470 million years old when the newly observed galaxy formed"
It’s so cool how we can look back in time…space is one big history/picture book!!!
Possible sighting of the Beagle
Quote:the choice of name for the probe was unfortunate."Beagles are notoriously difficult to control when let off the leash"
I house sat a Beagle once, he lasted 45 minutes, he was evicted to never return
More on distant galaxies found in deep space, great pics at the site…
Oddball Galaxies Picture Gallery :aliensmile:
Hubble finds farthest galaxies
Oddball galaxies existed following Big Bang
By Tariq Malik and Robert Roy Britt
SPACE.com
Tuesday, March 9, 2004 Posted: 1:21 PM EST (1821 GMT)Called the Hubble Ultra Deep Field, the million-second-long exposure reveals the first galaxies to emerge from the time after the Big Bang when the first stars reheated the cold, dark universe.
(SPACE.com) — Astronomers using the Hubble Space Telescope (HST) unveiled the deepest look into the universe yet, a portrait of what could be the most distant galaxies ever seen.
The new image, called the Hubble Ultra Deep Field (HUDF), includes objects that until now have been too faint to be seen and includes ancient galaxies that emerged just 700 million years after the Big Bang from what astronomers call the "Dark Ages" of the universe.
"This image is the deepest view in the visible that we’ve ever taken, where an object about as bright as a firefly on the Moon would be visible," said Massimo Stiavelli, of the Space Telescope Science Institute (STScI) in Baltimore and the UHDF project leader.
Stiavelli said the new image is six times more sensitive than previous deep sky surveys and four times better than even Hubble’s last faraway looks, the Hubble Deep Fields (HDFs), taken in 1995 and 1998.
"It has these extra colors with extra red shifts, which leads you to the end of the Dark Ages, something you couldn’t do with the HDF," he added.
The HUDF field contains an estimated 10,000 galaxies in a patch of sky one-tenth the diameter of the full moon located in the constellation Fornax, a region just below the constellation Orion. Hubble took one million seconds to take the HUDF, which appears in an area of the sky that appears largely empty if observed by ground-based instruments.
This new view is actually two separate images taken by Hubble’s Advanced Camera for Surveys (ACS) and the Near Infrared Camera and Multi-object Spectrometer (NICMOS). The combination of ACS and NICMOS images will be used to search for galaxies that existed between 800 and 400 million years after the Big Bang.
But it’s the NICMOS instrument that will reveal the farthest galaxies ever seen, because only it can detect light stretched past the visible, far into the near-infrared spectrum. Astronomers can tell how old a galaxy is by measuring the light it emits, specifically the amount of light that has been shifted toward the red end of the spectrum.
The higher red shift a galaxy has, the more distant it is and the earlier it existed in the universe. Hubble researchers are confident their new image contains galaxies whose light has been stretched to a red shift of 6 or more.
STScI researchers said there’s even a good case that it contains ancient galaxies of red shift 12, which would place them about 300 million years after the Big Bang.
Mario Livio, head of the Institute Science Division at Space Telescope Science Institute, says that if red shift 12 galaxies are indeed in the image, they will be found soon.
"It could happen this afternoon," Livio said in an interview prior to the Hubble announcement. "That might be stretching it a bit, but it will be easy."
Stiavelli, head of ultra deep field observations, said that finding a red shift 12 galaxy will be important because it will be done not with a gravitational lens, but "by brute force."
The ACS field is studded with a wide range of galaxies of various sizes, shapes, and colors. In vibrant contrast to the image’s rich harvest of classic spiral and elliptical galaxies, there is a zoo of oddball galaxies littering the field. Some look like toothpicks, others like links on a bracelet. A few galaxies appear to be interacting.
These oddball galaxies, that existed 800 million years after the Big Bang, chronicle a period when the universe was chaotic, when order and structure were just beginning to emerge.
"The images will also help us prepare for the next step from NICMOS on Hubble to the forthcoming James Webb Space Telescope. The NICMOS images reach back to the distance and time that Webb is destined to explore at much greater sensitivity," explained Rodger Thompson of the University of Arizona and the NICMOS principal investigator.
The entire HUDF was observed with the advanced camera’s "grism" spectrograph, an instrument used to measure distances to these distant objects.
"The grism spectra have already yielded the identification of about a thousand objects. Included among them are some of the intensely faint and red points of light in the ACS image, prime candidates for distant galaxies," said Sangeeta Malhotra of the STScI and Principal Investigator for the Ultra Deep Field’s ACS grism follow-up study.
"Based on those identifications, some of these objects are among the farthest and youngest galaxies ever seen. The grism spectra also distinguish among other types of very red objects, such as old and dusty red galaxies, quasars and cool dwarf stars," she said.
The ACS picture required a series of exposures taken over the course of 400 HST orbits around Earth from September 24, 2003, to January 16, 2004.
The size of a phone booth, ACS captured ancient photons of light that began traversing the universe even before Earth existed. Photons of light from the very faintest objects arrived at a trickle of one photon per minute, as opposed to millions of photons per minute from nearer galaxies.
Astronomers are eager to see the Hubble receive a stay of execution in the form of future servicing missions by NASA’s space shuttles to extend the telescope’s lifetime. Adam Riess, a supernova researcher for STScI, said an extension could help astronomers find supernova early in the universe’s lifetime.
"There are no supernovae in this deep field, but the results show that supernova in the early universe could be found if Hubble could be extended," Riess said. "Those could provide valuable insight into dark energy and fate of the universe."
The STScI is operated by the Association of Universities for Research in Astronomy, Inc. under contract with NASA’s Goddard Space Flight Center, Greenbelt, Maryland. The HST is a project of international cooperation between NASA and the European Space Agengy.
Detailed Viewer’s Guide: Five Planets Soon Visible :aliensmile:
By Joe Rao
SPACE.com’s Night Sky Columnist
posted: 07:00 am ET
12 March 2004There are four planets visible to the naked eye now, and a fifth will begin to make brief appearances in the evening sky during the week of March 14. Not until April 2036 will there be another chance to readily see all five naked-eye planets at the same time in the evening.
The sky show will be at its best from late March into the first days of April: the five brightest naked-eye planets will all be simultaneously in view in the early evening sky from roughly 45 to 90 minutes after sunset. In addition, from March 22 through April 2, the Moon will traverse the scene and on some evenings will appear to pass close to this or that world.
Observing details for all five planets are presented in the order that they will appear across the sky, going from west-to-east:
MERCURY: This most elusive of naked-eye planets could be spotted by keen observers beginning this weekend, but most folks will need it to climb a bit higher in the sky. Mercury is much lower and less bright than brilliant Venus, but it should nevertheless be easy to find during the second half of March. Other than Venus, no star or planet low in the western evening sky competes with Mercury for brightness. The trick is picking it out just after the Sun sets, because Mercury itself follows the Sun down quickly.
Mercury passed through superior conjunction (going behind the Sun) on March 4, then began to race around the Sun toward Earth much the way Venus is doing, only faster.
Beginning March 16 Mercury should be easily visible a little above the western horizon, being at magnitude –1.3 (almost as bright as Sirius, the brightest star) and setting an hour after the Sun. It’s at greatest elongation (farthest east of the Sun) on the evening of March 29. By that time is will appear as a zero-magnitude star-like object setting shortly after evening twilight ends.
Although this speedy planet gets no farther than 19 degrees from the Sun, this apparition is the year’s best for the Northern Hemisphere.
Look for a slender crescent Moon hovering well above and to Mercury’s left on the evening of March 22. During the first few evenings of April, Mercury can still be spotted. On the evening of April 1, look for it about 45 minutes after sunset, shining at magnitude +0.6. Fading rapidly to magnitude +1.6 and setting much earlier each night, this planet will become difficult to see by April 5. Inferior conjunction with the Sun will take place again on April 17.
VENUS: The brightest of all planets continues to grow more brilliant, reaching magnitude –4.4 by the end of March. Only the Moon can outshine Venus in the night sky. The best of this Venus apparition is yet to come: greatest apparent separation from the Sun (greatest eastern elongation: 46 degrees) occurs on March 29 – the same day as Mercury’s.
Greatest brilliancy for Venus will come in May, followed by a dramatic plunge toward an exceedingly rare transit across the Sun’s disk on June 8.
Venus is now as high as it ever gets for evening viewers at mid-northern latitudes, remaining up for about four hours after the Sun goes down. On the evening of March 24, just more than two degrees will separate Venus from a lovely crescent Moon. An added bonus will be Venus’s closest approach to the Pleiades Star Cluster just a few days after its peak altitude and greatest elongation.
Indeed, on the evenings of April 2 and 3 it will be less than 1 degrees from the brightest Pleiad, 3rd-magnitude Alcyone, with the brilliant light from Venus almost overwhelming it. As a matter of fact, you may need binoculars to properly see the Pleiades on these nights, whereas several nights before and after, the separation from Venus is enough to allow the star cluster to stand out.
Telescopic observers should try to view the planet’s "half-moon" phase before the sky fully darkens and Venus becomes too dazzling. Yes, Venus goes through phases.
MARS: The red planet starts March in Aries, the Ram and crosses over into Taurus, the Bull on March 13. It stands high in the west-northwest at dusk and sets between 11 and 11:30 p.m. all through March. It continues to dim as it moves away from Earth.
On March 1, it’s 155 million miles away and appears at magnitude +1.1 (as bright as the star Pollux). By month’s end, its distance from us has increased by more than 29 million miles and it’s down to magnitude +1.4 (as bright as Regulus).
On the evenings of March 20 and 21, Mars will slip about 3 degrees to the south of the Pleiades Star Cluster. Then during the evening of March 25, a fat crescent Moon will appear to pass closely to the north of Mars. For those living across northern Canada, Greenland and Iceland, the Moon will appear to occult or hide Mars.
As April gets underway, Mars will be located between the V-shaped Hyades and Pleiades star clusters. It may be hard to believe that this was the same object that made headlines last August when it passed so near to the Earth and outshone everything in the night sky except for the Moon and Venus!
SATURN: In Gemini, the Twins, Saturn stands high in the east-southeast sky at dusk. It sets shortly after 3 a.m. local time on March 1; about two hours earlier by the end of the month. Small telescopes continue to provide a wonderful view of Saturn’s beautiful ring system.
In addition, Saturn will be at east quadrature (90 degrees east of the Sun) on March 26, so this month is a good time to see the shadow of the planet cast farthest to its eastern side, giving the planet and its rings a greater depth in appearance.
The Moon visits Saturn on March 28, Saturn appearing as a bright yellowish-hued "star" below and to the Moon’s right.
JUPITER: The giant gas planet shines as a brilliant silvery "star" in Leo low in the eastern sky as dusk arrives. It is unmistakably the brightest star or planet in the region of sky it inhabits. Jupiter arrived at opposition to the Sun – rising as the Sun sets, highest in the sky at midnight and setting at sunrise – on March 4 and will now climb higher in the evening every week thereafter.
During mid-March the giant planet is ready for telescopic observing some 30 degrees up in the east by about 8 p.m. local time. It’s higher in the evening at later times and dates.
Jupiter reaches its highest position in the south around midnight and is heading toward its setting in the west during dawn. Besides its prominent cloud belts, the smallest telescope – even steadily held 7-power binoculars – will reveal the four bright satellites of Jupiter as tiny stars nearly in line and changing their places in the line as they revolve around the planet in orbits nearly edgewise to us.
On the evening of April 2, the Moon will pay Jupiter a visit, the giant planet appearing as a bright silvery "star" shining to the Moon’s right.
"Coma Girl" wrote:There are four planets visible to the naked eye now, and a fifth will begin to make brief appearances in the evening sky during the week of March 14. Not until April 2036 will there be another chance to readily see all five naked-eye planets at the same time in the evening.Wow, that surely must result into some massive cosmic energy waves ascending (or descending) upon us…..
Scientists Find Another Huge Mini-World in Outer Solar System :aliensmile:
By Robert Roy Britt
Senior Science Writer
15 March 2004The most distant object ever seen orbiting the Sun is nearly as large as Pluto, expanding astronomers notions of how the solar system formed and what resides in its outskirts
Controversial Proposal Would Boost Solar System’s Planet Tally to 12The round world is currently three times farther away than Pluto from the Sun, a distance that expands even further on its 10,000-year orbit. It sits in a part of the solar system that some astronomers had thought empty. It is redder and brighter than anything astronomers have seen in the outer solar system, and scientists don’t know why.
The object may even have its own little moon.
"There’s absolutely nothing else like it known in the solar system," said Michael Brown of the California Institute of Technology in Pasadena, Calif.
Other researchers say they’re not even sure how to classify the object, and the puzzling discovery is just the beginning of many years of investigation that will be needed to figure out the nature of space beyond Neptune.
Meet Sedna
The object is catalogued as 2003 VB12 and has unofficially been dubbed Sedna, goddess of the sea for Arctic dwellers. Brown thought that appropriate given the frigid conditions under which the solar system body has probably always existed. The International Astronomical Union would have to approve the name.
The discovery was led by Brown, who discussed it today at a NASA press conference.
Brown does not consider Sedna to be a planet. He and many other astronomers maintain that Pluto should not have ever received planet status, either, since astronomers are now finding myriad round objects beyond the orbit of Neptune, and several of them are quite large.
Pluto is about 1,413 miles (2,274 kilometers) wide. Sedna is estimated at no more than 1,100 miles (1,770 kilometers) in diameter. It may be the largest object in the solar system after Pluto, but more observations are needed to pin that down.
Sedna is some 8 billion miles away, or 86 astronomical units (AU) from the Sun. One AU is the distance from Earth to the Sun (93 million miles). Pluto is, on average, 39.5 AU from the Sun. But Sedna’s orbit, tracked since November when it was first spotted, can bring the object out to some 84 billion miles. It is a very elliptical orbit.
"If you were stand on the surface of Sedna today and you held a pin at arms length, you cold cover the entire Sun with the head of that pin," Brown said. Even the largest backyard telescopes would have a hard time spotting Sedna from Earth, he said.
The region beyond Pluto is commonly called the Kuiper Belt. It is loaded with icy objects large and small.
Most primordial object
Brown said Sedna may be the most primordial object ever detected, having undergone very little heating by the Sun and having had few collisions in the sparse region of space where it resides. Other objects in the solar system, according to the latest thinking, have typically been transformed significantly since their formation.
The next two largest Kuiper Belt Objects were also discovered by Brown’s group. Both were much closer.
Last month, the team announced 2004 DW, which was estimated to be between 520-1,170 miles wide (840 to 1,880 kilometers). The best estimate is that 2004 DW is 994 miles across (1,600 kilometers). It is nearly 47 AU from the Sun.
In 2002, the group found 2002 LM60, also named Quaoar (KWAH-o-ar). It is roughly 780 miles (1,250 kilometers) wide, about half as big as Pluto. Quaoar is 42 AU from the Sun.
Eugene Chiang, an astronomer at the University of California at Berkeley, told SPACE.com that the discovery of Sedna adds to the case that Pluto is more like a Kuiper Belt Object than a planet. He called Pluto’s discovery, in 1930, an accident of history.
"If Pluto were discovered after all these discoveries, would we have called it a planet? No," said Chiang, who was not involved in the Sedna discovery.
Strange origins
Brown said Sedna occupies a region of space beyond the Kuiper Belt but inside the theorized Oort Cloud, a distant reservoir of icy comets that are detected only when they zoom through the inner solar system on occasion. The Oort Cloud is thought to extend halfway to the next known star, but scientists know almost nothing about its scope, density or composition.
Brown said the discovery suggests the Oort Cloud might be more dense — containing more objects — than was previously thought.
"It is very likely that there are more inner Oort cloud objects like Sedna," Brown says, noting that only 15 percent of the sky has been surveyed for objects so dim as this.
Sedna probably was formed nearer to the Sun, in what’s now the Kuiper Belt. Like other objects there, it would have been gravitationally booted outward by the giant planets early in the 4.6-billion-year history of the solar system. Many such objects should have been ejected from the solar system. But interactions with very distant stars could have forced some to remain in the Oort Cloud.
Sedna’s presence suggests, Brown said, that the Sun might have formed in a neighborhood more tightly packed with stars than what’s evident today. Other theories of planet formation have suggested this, too, holding that the Sun was long ago booted out of the star cluster in which it was born.
Another view
It is not certain, however, that Sedna should be considered part of the Oort cloud, said Alan Stern of the Southwest Research Institute (SwRI).
"I think it’s a really cool find," Stern said in a telephone interview, but he added that it was "not unexpected."
Stern heads up NASA’s New Horizons mission that will launch in 2006 and explore Pluto and the Kuiper Belt. He expects the spacecraft to be functional at least out to 50 AU — short of Sedna’s distant location.
Stern and others have long theorized that there would be many objects beyond the orbit of Neptune. He said Sedna might turn out to be a Kuiper Belt Object that has been scattered outward. The problem, he said, is that scientists don’t know enough about either region to say for sure what belongs where and what is or isn’t in between.
"I think the jury is out on whether it’s a scattered Kuiper Belt Object or an Oort Cloud object," Stern said. "There’s a fair chance Mike [Brown] is right." Stern said it is not even clear whether there is actually a gap between the two regions.
Stern said only multiple missions to the Kuiper Belt and beyond would answer all the questions he has about the far reaches of the solar system.
Composition unknown
Scientists don’t know what Sedna is made of, but they presume it is about half ice and half rock, like other distant solar system bodies. But Sedna appears redder than all but Mars, Brown said, and observations over the next six months or so aim to learn why.
Observations suggest Sedna has a satellite — a small moon, but further study is needed to determine if that’s the case, Brown said. He and other astronomers would not be overly surprised, as several Kuiper Belt Objects, as well as Pluto, have satellites.
Sedna’s surface temperature is about minus 400 degrees Fahrenheit (-240 Celsius), the coldest known place in the solar system.
Sedna was found using the 48-inch Samuel Oschin Telescope at Caltech’s Palomar Observatory near San Diego. The discovery was confirmed with other observatories, and the object’s size was pinned down using NASA’s new Spitzer Space Telescope.
100-foot asteroid to fly by Earth (from cnn.com)
…close encounter….
Monday 22nd March 2004
SETI coffers boosted by Paul Allen donation
Reuters
March 22, 2004, 10:50 GMThe co-founder of Microsoft has made a multimillion-dollar donation to the search for ET and friends
Microsoft co-founder Paul Allen has donated $13.5m to help fund the search for extraterrestrial life.
The California-based SETI Institute, which is dedicated to the search for life beyond Earth, said the donation from Allen, who co-founded Microsoft with Bill Gates, would be used to create a radio telescope array of more than 200 satellite dishes that will measure signals from space.
SETI, which stands for Search for Extraterrestrial Intelligence, plans ultimately to increase the array to a total of 350 satellite dishes.
"An instrument of this magnitude…will result in the expansion of our understanding of how the universe was formed, and how it has evolved and our place therein," Allen said in a statement.
A long-time science fiction fan, Allen has already devoted millions of dollars to exploring outer space and is building a science fiction museum in his hometown of Seattle.
His donation comes at a time of a renewed interest in space exploration. NASA’s Mars rovers have discovered evidence of water on the surface of the Red Planet and President George W. Bush has outlined plans for an ambitious space initiative, including a manned mission to Mars.
:aliensmile:
![[img]http://www.ibiblio.org/wm/paint/auth/gogh/starry-night/gogh.starry-night.small.jpg[/img]](http://www.ibiblio.org/wm/paint/auth/gogh/starry-night/gogh.starry-night.jpg){kind=link}
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