MADRID (AFP) - Spanish astronomers Wednesday announced the discovery of the smallest planet discovered to date outside the solar system, located 30 light years from earth.
The planet, "GJ 436T", was detected through a new technique which "will allow us to discover in less than 10 years the first planet resembling earth in terms of mass and orbit," said Ignasi Ribas of Spain's CSIC scientific research institute.
It was discovered by a team led by Ribas through its gravitational pull on other planets already discovered around the same star in the constellation of Leo.
"GJ 436T" has a mass five times the size of Earth, which makes it the smallest extrasolar planet among the roughly 300 identified so far, Ribas said in announcing the discovery.
More.
NVDL: Maybe it's big enough for Earth's human population, (and far enough to be at a minimum safe distance from Earth's original ecosystem to pose a minimal risk of re-infection) since we apparently need 1.4 planets for all the cargo pants, SUV's and DVDs that we buy every day.
Showing posts with label data from Crashed Spacecraft. Show all posts
Showing posts with label data from Crashed Spacecraft. Show all posts
Thursday, April 10, 2008
Tuesday, February 19, 2008
Satellite Shoot-Down Set: Intercept Near Hawaii; Debris Cloud Over Canada (Updated)
As you probably know by now, the U.S. military is going to try to shoot down a dying satellite on Thursday, around 10:30 pm eastern time, before it plummets into the atmosphere. That's right smack in the middle of a lunar eclipse, which should make the machine easier to track. Satellite-watchers have figured out where the Navy cruiser will take its shot -- and where the debris cloud is likely to go afterwards.More from this WIRED article.
Operation Rogue Satellite: The Latest
Tuesday, December 11, 2007
Best Meteor Shower of 2007 Peaks Dec. 13
What could be the best meteor display of the year will reach its peak on the night of Dec.13-14.
Here is what astronomers David Levy and Stephen Edberg have written of the annual Geminid Meteor Shower: "If you have not seen a mighty Geminid fireball arcing gracefully across an expanse of sky, then you have not seen a meteor."
The Geminids get their name from the constellation of Gemini, the Twins, because the meteors appear to emanate from a spot in the sky near the bright star Castor in Gemini.
Also in Gemini this month is the planet Mars, nearing a close approach to the Earth later this month, and shining brilliantly with yellow-orange hue. To be sure, Mars is certain to attract the attention of prospective Geminid watchers this upcoming week.
Reliable shower
The Geminid Meteors are usually the most satisfying of all the annual showers, even surpassing the famous Perseids of August.
Studies of past find the "Gems" have a reputation for being rich both in slow, bright, graceful meteors and fireballs as well as faint meteors, with relatively fewer objects of medium brightness.
They are of medium speed, encountering Earth at 22 miles per second (35 kps). They are bright and white, but unlike the Perseids, they leave few visible trails or streaks. They are four times denser than most other meteors, and have been observed to form jagged or divided paths.
Geminids also stand apart from the other meteor showers in that they seem to have been spawned not by a comet, but by 3200 Phaethon, an Earth-crossing asteroid. Then again, the Geminids may be comet debris after all, for some astronomers consider Phaethon to really be the dead nucleus of a burned-out comet that somehow got trapped into an unusually tight orbit. Interestingly, on December 10, Phaethon will be passing about 11 million miles (18 million kilometers) from Earth, its closest approach since its discovery in 1983.
The prospects for this year
The Geminids perform excellently in any year, but British meteor astronomer, Alastair McBeath, has categorized 2007 as a "great year."
Last year's display was hindered somewhat by the moon, two days past last quarter phase. But this year, the moon will be at new phase on Dec. 9. On the peak night, the moon will be a fat crescent, in the south-southwest at dusk and setting soon after 8 p.m. That means that the sky will be dark and moonless for the balance of the night, making for perfect viewing conditions for the shower.
According to McBeath, the Geminids are predicted to reach peak activity on Dec. 14 at 16:45 GMT. That means those places from central Asia eastwards across the Pacific Ocean to Alaska are in the best position to catch the very crest of the shower, when the rates conceivably could exceed 120 per hour.
"But," he adds, "maximum rates persist at only marginally reduced levels for some 6 to 10 hours around the biggest ones, so other places (such as North America) should enjoy some fine Geminid activity as well.
Indeed, under normal conditions on the night of maximum activity, with ideal dark-sky conditions, at least 60 to 120 Geminid meteors can be expected to burst across the sky every hour on the average (Light pollution greatly cuts the numbers).
The Earth moves quickly through this meteor stream producing a somewhat broad, lopsided activity profile. Rates increase steadily for two or three days before maximum, reaching roughly above a quarter of its peak strength, then drop off more sharply afterward. Late Geminids, however, tend to be especially bright. Renegade forerunners and late stragglers might be seen for a week or more before and after maximum.
What to do
Generally speaking, depending on your location, Gemini begins to come up above the east-northeast horizon right around the time evening twilight is coming to an end. So you might catch sight of a few early Geminids as soon as the sky gets dark.
There is a fair chance of perhaps catching sight of some "Earth-grazing" meteors. Earth grazers are long, bright shooting stars that streak overhead from a point near to even just below the horizon. Such meteors are so distinctive because they follow long paths nearly parallel to our atmosphere.
The Geminids begin to appear noticeably more numerous in the hours after 10 p.m. local time, because the shower's radiant is already fairly high in the eastern sky by then. The best views, however, come around 2 a.m., when their radiant point will be passing very nearly overhead.
The higher a shower's radiant, the more meteors it produces all over the sky.
But keep this in mind: At this time of year, meteor watching can be a long, cold business. You wait and you wait for meteors to appear. When they don't appear right away, and if you're cold and uncomfortable, you're not going to be looking for meteors for very long! The late Henry Neely (1878-1963), who for many years served as a lecturer at New York's Hayden Planetarium, once had this to say about watching for the Geminids: "Take the advice of a man whose teeth have chattered on many a winter's night – wrap up much more warmly than you think is necessary!"
By Joe Rao
SPACE.com Skywatching Columnist
NVDL: Unfortunately for us in South Africa, the far North West and Central and North Eastern Hemisphere (around Alaska and Asia) are likely to get the best views of this.
Here is what astronomers David Levy and Stephen Edberg have written of the annual Geminid Meteor Shower: "If you have not seen a mighty Geminid fireball arcing gracefully across an expanse of sky, then you have not seen a meteor."
The Geminids get their name from the constellation of Gemini, the Twins, because the meteors appear to emanate from a spot in the sky near the bright star Castor in Gemini.
Also in Gemini this month is the planet Mars, nearing a close approach to the Earth later this month, and shining brilliantly with yellow-orange hue. To be sure, Mars is certain to attract the attention of prospective Geminid watchers this upcoming week.
Reliable shower
The Geminid Meteors are usually the most satisfying of all the annual showers, even surpassing the famous Perseids of August.
Studies of past find the "Gems" have a reputation for being rich both in slow, bright, graceful meteors and fireballs as well as faint meteors, with relatively fewer objects of medium brightness.
They are of medium speed, encountering Earth at 22 miles per second (35 kps). They are bright and white, but unlike the Perseids, they leave few visible trails or streaks. They are four times denser than most other meteors, and have been observed to form jagged or divided paths.
Geminids also stand apart from the other meteor showers in that they seem to have been spawned not by a comet, but by 3200 Phaethon, an Earth-crossing asteroid. Then again, the Geminids may be comet debris after all, for some astronomers consider Phaethon to really be the dead nucleus of a burned-out comet that somehow got trapped into an unusually tight orbit. Interestingly, on December 10, Phaethon will be passing about 11 million miles (18 million kilometers) from Earth, its closest approach since its discovery in 1983.
The prospects for this year
The Geminids perform excellently in any year, but British meteor astronomer, Alastair McBeath, has categorized 2007 as a "great year."
Last year's display was hindered somewhat by the moon, two days past last quarter phase. But this year, the moon will be at new phase on Dec. 9. On the peak night, the moon will be a fat crescent, in the south-southwest at dusk and setting soon after 8 p.m. That means that the sky will be dark and moonless for the balance of the night, making for perfect viewing conditions for the shower.
According to McBeath, the Geminids are predicted to reach peak activity on Dec. 14 at 16:45 GMT. That means those places from central Asia eastwards across the Pacific Ocean to Alaska are in the best position to catch the very crest of the shower, when the rates conceivably could exceed 120 per hour.
"But," he adds, "maximum rates persist at only marginally reduced levels for some 6 to 10 hours around the biggest ones, so other places (such as North America) should enjoy some fine Geminid activity as well.
Indeed, under normal conditions on the night of maximum activity, with ideal dark-sky conditions, at least 60 to 120 Geminid meteors can be expected to burst across the sky every hour on the average (Light pollution greatly cuts the numbers).
The Earth moves quickly through this meteor stream producing a somewhat broad, lopsided activity profile. Rates increase steadily for two or three days before maximum, reaching roughly above a quarter of its peak strength, then drop off more sharply afterward. Late Geminids, however, tend to be especially bright. Renegade forerunners and late stragglers might be seen for a week or more before and after maximum.
What to do
Generally speaking, depending on your location, Gemini begins to come up above the east-northeast horizon right around the time evening twilight is coming to an end. So you might catch sight of a few early Geminids as soon as the sky gets dark.
There is a fair chance of perhaps catching sight of some "Earth-grazing" meteors. Earth grazers are long, bright shooting stars that streak overhead from a point near to even just below the horizon. Such meteors are so distinctive because they follow long paths nearly parallel to our atmosphere.
The Geminids begin to appear noticeably more numerous in the hours after 10 p.m. local time, because the shower's radiant is already fairly high in the eastern sky by then. The best views, however, come around 2 a.m., when their radiant point will be passing very nearly overhead.
The higher a shower's radiant, the more meteors it produces all over the sky.
But keep this in mind: At this time of year, meteor watching can be a long, cold business. You wait and you wait for meteors to appear. When they don't appear right away, and if you're cold and uncomfortable, you're not going to be looking for meteors for very long! The late Henry Neely (1878-1963), who for many years served as a lecturer at New York's Hayden Planetarium, once had this to say about watching for the Geminids: "Take the advice of a man whose teeth have chattered on many a winter's night – wrap up much more warmly than you think is necessary!"
By Joe Rao
SPACE.com Skywatching Columnist
NVDL: Unfortunately for us in South Africa, the far North West and Central and North Eastern Hemisphere (around Alaska and Asia) are likely to get the best views of this.
Monday, October 22, 2007
Nature: Crashed spacecraft yields data
By Nicola Jones
Researchers have been able to salvage usable material from the Genesis mission, whose aim was to collect samples from the solar wind and bring them safely back to Earth. The results, picked from millimetre-sized shards of the spacecraft's detectors, provide a snapshot of the early Solar System, and will feed into models that outline how our planet’s atmosphere evolved. “Great measurements can be made on small objects,” says Genesis scientist Roger Wiens of the Los Alamos National Laboratory in New Mexico.
The Genesis mission spent 27 months in space with its innards spread open to the Sun, gathering tiny samples from different types of solar wind. Its delicate and contamination-sensitive collectors were due to be returned to Earth using an unusual technique — Hollywood stunt pilots were enlisted to swoop by in a helicopter and catch the falling capsule. But the craft’s parachute did not open, and the careening craft ploughed a hole into the desert. Observers were initially devastated that the spacecraft had crashed, but researchers soon realized that data could be salvaged — albeit more slowly and with more effort.
“The landing didn't help”
Roger Wiens
“We had originally hoped we could publish a series of papers within a year,” says Wiens. It has taken much longer than that, but a series of four papers have now been published in Space Science Reviews 1,2,3,4, and a fifth follows this week in Science 5. A preliminary paper was also published last year6.
The team remains hopeful that they will soon be able to complete the main goal of their original mission: solving the mystery of the unique isotopic signature of different objects in our galaxy.
For the rest of this Nature.com article go here.
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