SpaceJibe

February 25, 2009

Galaxy may be full of ‘Earths,’ alien life

(CNN) — As NASA prepares to hunt for Earth-like planets in our corner of the Milky Way galaxy, there’s new buzz that “Star Trek’s” vision of a universe full of life may not be that far-fetched.

An artists impression shows a planet passing in front of its parent star. Such events are called transits.

An artist's impression shows a planet passing in front of its parent star. Such events are called transits.

Pointy-eared aliens traveling at light speed are staying firmly in science fiction, but scientists are offering fresh insights into the possible existence of inhabited worlds and intelligent civilizations in space.

There may be 100 billion Earth-like planets in the Milky Way, or one for every sun-type star in the galaxy, said Alan Boss, an astronomer with the Carnegie Institution and author of the new book “The Crowded Universe: The Search for Living Planets.”

He made the prediction based on the number of “super-Earths” — planets several times the mass of the Earth, but smaller than gas giants like Jupiter — discovered so far circling stars outside the solar system.

Boss said that if any of the billions of Earth-like worlds he believes exist in the Milky Way have liquid water, they are likely to be home to some type of life.

“Now that’s not saying that they’re all going to be crawling with intelligent human beings or even dinosaurs,” he said.

“But I would suspect that the great majority of them at least will have some sort of primitive life, like bacteria or some of the multicellular creatures that populated our Earth for the first 3 billion years of its existence.”

Putting a number on alien worlds

Other scientists are taking another approach: an analysis that suggests there could be hundreds, even thousands, of intelligent civilizations in the Milky Way.

Researchers at the University of Edinburgh in Scotland constructed a computer model to create a synthetic galaxy with billions of stars and planets. They then studied how life evolved under various conditions in this virtual world, using a supercomputer to crunch the results.

In a paper published recently in the International Journal of Astrobiology, the researchers concluded that based on what they saw, at least 361 intelligent civilizations have emerged in the Milky Way since its creation, and as many as 38,000 may have formed.

Duncan Forgan, a doctoral candidate at the university who led the study, said he was surprised by the hardiness of life on these other worlds.

“The computer model takes into account what we refer to as resetting or extinction events. The classic example is the asteroid impact that may have wiped out the dinosaurs,” Forgan said.

“I half-expected these events to disallow the rise of intelligence, and yet civilizations seemed to flourish.”

Forgan readily admits the results are an educated guess at best, since there are still many unanswered questions about how life formed on Earth and only limited information about the 330 “exoplanets” — those circling sun-like stars outside the solar system — discovered so far.

The first was confirmed in 1995 and the latest just this month when Europe’s COROT space telescope spotted the smallest terrestrial exoplanet ever found. With a diameter less than twice the size of Earth, the planet orbits very close to its star and has temperatures up to 1,500° Celsius (more than 2,700° Fahrenheit), according to the European Space Agency. It may be rocky and covered in lava.

Johannes Kepler - brilliant student of Danish astronomer Tycho Brahe

Johannes Kepler - brilliant student of Danish astronomer Tycho Brahe

Hunt for habitable planets

NASA is hoping to find much more habitable worlds with the help of the upcoming Kepler mission. The spacecraft, set to be launched from Cape Canaveral Air Force Station in Florida next week, will search for Earth-size planets in our part of the galaxy.

Kepler contains a special telescope that will study 100,000 stars in the Cygnus-Lyra region of the Milky Way for more than three years. It will look for small dips in a star’s brightness, which can mean an orbiting planet is passing in front it — an event called a transit.

“It’s akin to measuring a flea as it creeps across the headlight of an automobile at night,” said Kepler project manager James Fanson during a during a NASA news conference.

The focus of the mission is finding planets in a star’s habitable zone, an orbit that would ensure temperatures in which life could exist. Video Watch a NASA scientist explain the search for habitable planets »

Boss, who serves on the Kepler Science Council, said scientists should know by 2013 — the end of Kepler’s mission — whether life in the universe could be widespread.

Explore the Kepler Mission: http://www.nasa.gov/mission_pages/kepler/main/index.html

Finding intelligent life is a very different matter. For all the speculation about the possibility of other civilizations in the universe, the question remains: If the rise of life on Earth isn’t unique and aliens are common, why haven’t they shown up or contacted us? The contradiction was famously summed up by the physicist Enrico Fermi in 1950 in what became known as the Fermi paradox: “Where is everybody?”

The answer may be the vastness of time and space, scientists explained.

“Civilizations come and go,” Boss said. “Chances are, if you do happen to find a planet which is going to have intelligent life, it’s not going to be in [the same] phase of us. It may have formed a billion years ago, or maybe it’s not going to form for another billion years.”

Even if intelligent civilizations did exist at the same time, they probably would be be separated by tens of thousands of light years, Forgan said. If aliens have just switched on their transmitter to communicate, it could take us hundreds of centuries to receive their message, he added.

As for interstellar travel, the huge distances virtually rule out any extraterrestrial visitors.

To illustrate, Boss said the fastest rockets available to us right now are those being used in NASA’s New Horizons mission to Pluto. Even going at that rate of speed, it would take 100,000 years to get from Earth to the closest star outside the solar system, he added.

“So when you think about that, maybe we shouldn’t be worried about having interstellar air raids any time soon,” Boss said.

Galaxy Quest

• The Milky Way is believed to be more than 13 billion years old.

• It is just one of billions of galaxies in the universe.

• The Milky Way has a circumference of about 250,000-300,000 light years.

• It is about 100,000 light years in diameter.

• There are three types of galaxies: ellipticals, spirals and irregulars.

• The Milky Way is a large disk-shaped barred spiral galaxy. (A barred galaxy has a bar-shaped structure in its middle.)

Source: Space.com

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February 24, 2009

Glimpse Before Big Bang Possible

Filed under: Cosmology, Wierd — bferrari @ 2:39 pm

The Universe appears to be lopsided, and a new model that aims to explain this anomaly could offer a glimpse of what happened before the birth of it all.

When astronomers look out at the cosmos, the view in one direction is turning out to be different than in the other. Specifically, fluctuations in the density and temperature of the radiation left over from the theoretical Big Bang called the Cosmic Microwave Background seem to be strangely larger on one side of the universe.

A new model suggests this unevenness could be caused by an imprint left over from before the beginning of the universe, that is, before the cosmos ballooned almost instantaneously from less than the size of an atom to about golf-ball size. This process is called inflation.

Blowing up the balloon

“Inflation theory does predict that we have these density and temperature fluctuations, but they should look the same everywhere across the sky,” said Caltech astrophysicist Sean Carroll, who worked on the new model, detailed in the Dec. 16 issue of the journal Physical Review D. “But people who look at the data say they see one side of the universe has bigger fluctuations, and that’s what we’re trying to get a handle on.”

Scientists think the normal variations in temperature and density predicted by inflation became the seeds for the structure we see today throughout the universe. Soon after inflation, the denser areas would have attracted more matter and eventually grown into the clusters and galaxies we see today, while less dense regions would have become voids mostly absent of galaxies, stars and planets.

But the normal model of inflation can’t account for the asymmetry now noted. To try to explain that, Carroll, astrophysicist Marc Kamionkowski and graduate student Adrienne Erickcek (all at Caltech) tested a new version of inflation theory, in which two fields are responsible for the universe’s early bloom of expansion.

In the standard theory of inflation, one field called the inflaton (not inflation) caused both the rapid expansion of the universe and its density fluctuations. But Kamionkowski and team found that an unevenness in the density fluctuations could arise if inflation is caused by two fields instead of one. In the new model, the inflaton is responsible for ballooning the size of the universe, while a second field called the curvaton that had been previously proposed introduces the density variations.

Before the Big Bang

The model also intriguingly hints at what might have come before inflation, since it suggests that the universe’s lopsidedness may be an aftereffect of a great fluctuation that occurred before inflation began.

“It’s no longer completely crazy to ask what happened before the Big Bang,” Kamionkowski said. “All of that stuff is hidden by a veil, observationally. If our model holds up, we may have a chance to see beyond this veil.”

The next step is to gather better data about the Cosmic Microwave Background, to confirm that the unevenness seen so far really holds up.

“So far it seems to be in the data, but that doesn’t mean it’s in the universe,” Carroll told SPACE.com. “There’s a chance this asymmetry is coming from errors in the data.”

A new European Space Agency satellite called Planck, designed to map the background radiation with unprecedented sensitivity and resolution, is set to launch in 2009. If Planck finds the radiation densities to be off-balance, too, then cosmologists must really come to terms with this puzzling aspect of inflation. Though it would require some serious amendments to current theories, many physicists would relish the challenge.

 Incomprehensible as it sound, inflation poses that the universe initially expanded far faster than the speed of light and grew from a subatomic size to a golf-ball size almost instantaneously. (NASA)

Incomprehensible as it sound, inflation poses that the universe initially expanded far faster than the speed of light and grew from a subatomic size to a golf-ball size almost instantaneously. (NASA)

“That’s what everyone wants — it’s much more interesting that way,” Carroll said.

Source

Comet’s Heart May Have Struck Earth

Filed under: Cosmology, Inner Solar System, Oort Cloud — bferrari @ 12:48 pm
A close-up image of the Bejar bolide, photographed from Torrelodones, Madrid, Spain.  (J. Perez Vallejo/SPMN)

A close-up image of the Bejar bolide, photographed from Torrelodones, Madrid, Spain. (J. Perez Vallejo/SPMN)

Bright lights that suddenly streak across the night sky with an accompanying boom tend to elicit a flurry of phone calls to local police departments.

These rare events aren’t typically wayward missiles, or satellite debris (as was thought when one such streak recently lit up the skies over Texas), or alien invasions. But they do come from outer space.

Scientists aptly call the objects fireballs because they are the brightest meteors, or “shooting stars,” that fall to Earth.

A fireball as bright as the full moon raced across the Spanish skies on July 11, 2008, and was tracked by the Spanish Fireball Network (SPMN). Researchers used the tracking data to trace the path of the comet backwards through the sky and space; they think the boulder may be a chunk of a comet that broke up nearly 90 years ago. Their conclusions are detailed in the Feb. 11 online issue of the journal Monthly Notices of the Royal Astronomical Society.

It’s possible that chunks of the fireball made it to the ground and are waiting to be picked up, the researchers said, which would give scientists a rare glimpse into the heart of a comet.

Meteors and fireballs

Earth and the other planets of the solar system are under constant bombardment from particles that range in size from a sand grain to a boulder and are collectively known as meteoroids. Many meteoroids are the detritus left over from collisions of asteroids and comets and impacts to other planets.

If a meteoroid enters Earth’s atmosphere, it starts to burn up, forming a bright streak in the sky, called a meteor. Meteors can come from asteroid or comet fragments. If that meteor is brighter than any of the planets in the sky, it is deemed a fireball (also called a bolide).

A blazing bolide can also create a sonic boom that can be heard up to 30 miles away — these explosive noises were heard over Kentucky on Friday, Feb. 13, and over Texas on Sunday, Feb. 15, causing a number of startled citizens to call local law enforcement.

Initial speculation that these streaks of light and accompanying boom were caused by debris from the Feb. 10 collision of two satellites was later refuted by astronomers, who said it was likely a meteor. Preston Starr, the observatory manager at the University of North Texas, told the Associated Press that the object would have been about the size of a truck and that somewhere between eight and 10 such objects burn up in the atmosphere every year.

Spanish sighting

The bolide that shot across the Spanish skies in July was also seen in Portugal and southern France.

At maximum intensity, it was 150 times brighter than the full moon. It was first picked up by the SPMN above Bejar in the western part of Spain at a height of about 61 miles (98 kilometers) and disappeared from view at about 13 miles (21 kilometers) above the surface of the Earth.

A professional photographer also snapped a picture of the streak from the north of Madrid.

From these images, astronomers Josep Trigo-Rodríguez of the Institute of Space Studies, CSIC-IEEC in Spain, Jose Madiedo of the University of Huelva-CIECEM in Spain and Iwan Williams of the University of London were able to deduce the trajectory and properties of the incoming fireball.

Their work was funded by the Spanish Ministry of Science and Innovation, the National Institute of Aerospatial Technique, and the Junta de Andalucía.

The team thinks the bolide was a dense object, about 3 feet (about 1 meter) across with a mass of about 4,000 pounds (1.8 tonnes). This would be like squeezing an adult elephant down to the size of an armchair.

The rock would have been big enough that chunks of it may have survived the fiery passage through the atmosphere and hit the ground as meteorites. Finding these pieces would be a boon to science if they are, as the team suspects, remnants of a comet breakup.

The bolide traveled an unusual orbit around the sun, as determined by the astronomers, following a path that took it from beyond the orbit of Jupiter to the vicinity of Earth. This orbit is similar to that of a cloud of dust particles known as the Omicron Draconids, which on rare occasions produce a minor meteor shower on Earth.

This collection of meteoroids is thought to originate from the breakup of Comet C/1919 Q2 Metcalf in 1920.

It has been proposed that comets consist of large boulders glued together by a mixture of smaller particles and ice. If the nucleus of the comet disintegrates, the boulders are set loose in space. Finding chunks of the Bejar bolide could help confirm this theory.

“Handling pieces of comet would fulfill the long-held ambitions of scientists — it would effectively give us a look inside some of the most enigmatic objects in the solar system,” Trigo-Rodríguez said.

Source

Failure hits Nasa’s ‘CO2 hunter’

Filed under: Global Warming, Government Policies, Space Exploration — bferrari @ 9:15 am

NASAs CO2 Hunter artist conception

NASA's CO2 Hunter artist conception

Nasa’s first mission to measure carbon dioxide (CO2) from space has failed following a rocket malfunction.

Officials said the fairing – the part of the rocket which covers the satellite on top of the launcher – had failed to separate properly.

Officials said the satellite had now crashed in Antarctica.

The Orbiting Carbon Observatory (OCO) was intended to help pinpoint the key locations on our planet’s surface where the gas is being emitted and absorbed.

Nasa officials confirmed the launch had failed at a press conference held at 1300 GMT.

The $270m mission was launched on a Taurus XL – the smallest ground-launched rocket currently in use by the US space agency.

Since its debut in 1994, this type of rocket has flown eight times, with six successes and two failures including this launch. But this is the first time Nasa has used the Taurus XL.

Nasa will now put together an investigation board to determine the root cause of the problem.

Onlookers watched the launcher soar into the sky from the Vandenberg Air Force Base in California at 0951 GMT on Tuesday.

The first indication of a problem came in an announcement made by the Nasa launch commentator, George Diller.

“This is Taurus launch control. We have declared a launch contingency, meaning that we did not have a successful launch tonight,” he said.

“The OCO spacecraft did not achieve orbit successfully in a way that we could have a mission. They’re still looking at the telemetry data here very carefully. It appears that we were getting indications that the fairing was having problems separating.

“It either did not separate or did not separate in the way that it should, but at any rate we’re still trying to evaluate exactly what the status of the spacecraft is at this point.”

Separation of the fairing was one of the last technical hurdles faced by the satellite as it flew into orbit. Orbital said there had been no changes to the design of the fairing since previous launches.

John Brunschwyler, from Orbital Sciences Corporation, the rocket’s manufacturer, cast doubt on any suggestion of a link between the failure and a power glitch which occurred to the vehicle before launch.

“That was on a separate system, so I do not believe there was any connection,” Mr Brunschwyler told journalists at the Nasa press conference.

Dr Paul Palmer, a scientist from the University of Edinburgh, who was collaborating on the mission, told BBC News: “I am bitterly disappointed about the loss of OCO. My thoughts go out to the science team that have dedicated the past seven years to building and testing the instrument.”

Scientists had hoped the OCO mission would improve models of the Earth’s climate and help researchers determine where the greenhouse gas is coming from and how much is being absorbed by forests and oceans.

Rebuild question

Only about 50% of carbon emitted into the atmosphere, for example from fossil fuel combustion and land use, stays there. Most of the remainder is mopped up by the forests and oceans, which act as “sinks”.

However, there appears to be a large carbon sink missing.

“All eyes are now on the Japanese Gosat instrument to search for the missing carbon sink,” said Dr Palmer.

Gosat was launched in January from Tanegashima in Japan. It is also designed to monitor atmospheric greenhouse gases.

Nasa’s Glory satellite, which is designed to measure carbon soot and other aerosols in the Earth’s atmosphere, is due to launch on a Taurus XL from California in June.

But the space agency said it would not fly Glory until the cause of OCO’s failure had been investigated.

When the European Space Agency’s Cryosat spacecraft was destroyed on launch in 2006, officials decided to re-build it; the launch is scheduled for later in the year. However, the future of the OCO mission remains unclear at this stage.

The only other failure to hit a Taurus rocket occurred in September 2001, when the rocket dropped off its payload of two satellites at a lower altitude than had been intended.

Source

February 17, 2009

Ex-Astronaut: Global Warming Is Bunk

Filed under: Earth, Global Warming, Stupidity — bferrari @ 9:20 am

Harrison Schmitt, the only geologist/scientist to visit the moon. (NASA)

Harrison Schmitt, the only geologist/scientist to visit the moon. (NASA)

By Bob Ferrari

Harrison Schmitt may unceremoniously have been the last astronaut to visit the moon, but he is actually more famous for being  an actual life-long scientist. A geologist by trade he is a brilliant scientist in his own right and he has a lot to say about the human-caused global warming fabrication.

Foxnews

SANTA FE, N.M. —  Former astronaut Harrison Schmitt, who walked on the moon and once served New Mexico in the U.S. Senate, doesn’t believe that humans are causing global warming.

“I don’t think the human effect is significant compared to the natural effect,” said Schmitt, who is among 70 skeptics scheduled to speak next month at the International Conference on Climate Change in New York.

Schmitt contends that scientists “are being intimidated” if they disagree with the idea that burning fossil fuels has increased carbon dioxide levels, temperatures and sea levels.

“They’ve seen too many of their colleagues lose grant funding when they haven’t gone along with the so-called political consensus that we’re in a human-caused global warming,” Schmitt said.

• Click here to visit FOXNews.com’s Natural Science Center.

Dan Williams, publisher with the Chicago-based Heartland Institute, which is hosting the climate change conference, said he invited Schmitt after reading about his resignation from The Planetary Society, a nonprofit dedicated to space exploration.

Schmitt resigned after the group blamed global warming on human activity.

In his resignation letter, the 74-year-old geologist argued that the “global warming scare is being used as a political tool to increase government control over American lives, incomes and decision-making.”

Williams said Heartland is skeptical about the crisis that people are proclaiming in global warming.

“Not that the planet hasn’t warmed. We know it has or we’d all still be in the Ice Age,” he said. “But it has not reached a crisis proportion and, even among us skeptics, there’s disagreement about how much man has been responsible for that warming.”

Schmitt said historical documents indicate average temperatures have risen by 1 degree per century since around 1400 A.D., and the rise in carbon dioxide is because of the temperature rise.

Schmitt also said geological evidence indicates changes in sea level have been going on for thousands of years. He said smaller changes are related to changes in the elevation of land masses — for example, the Great Lakes are rising because the earth’s crust is rebounding from being depressed by glaciers.

Schmitt, who grew up in Silver City and now lives in Albuquerque, has a science degree from the California Institute of Technology. He also studied geology at the University of Oslo in Norway and took a doctorate in geology from Harvard University in 1964.

In 1972, he was one of the last men to walk on the moon as part of the Apollo 17 mission.

Schmitt said he’s heartened that the upcoming conference is made up of scientists who haven’t been manipulated by politics.

Of the global warming debate, he said: “It’s one of the few times you’ve seen a sizable portion of scientists who ought to be objective take a political position and it’s coloring their objectivity.”

Source

February 11, 2009

German Jetpack Runs for Hours on Water

Filed under: Gadgets — bferrari @ 2:42 pm
Making a big splash with the JetLev water-powered jetpack. (MS Watersports GmbH)

Making a big splash with the JetLev water-powered jetpack. (MS Watersports GmbH)

It’s cool. It’s fast. And it lasts more than 30 seconds.

Jet packs have been around for half a century, but there’s always been one problem: They run out of rocket fuel very quickly.

Now a German company appears to have broken the time barrier by using an alternative fuel: Water, lots of it.

MS Watersports GmbH of Itzehoe, near Hamburg in northern Germany, takes the standard jetpack design and run a fat yellow hose out the back.

A young woman goes airborne using the JetLev water-powered jetpack. ( MS Watersports GmbH)

A young woman goes airborne using the JetLev water-powered jetpack. ( MS Watersports GmbH)

The hose connects to a small unmanned boat, which houses an engine, pump and fuel tank and sends pressurized water back up the hose, where it’s shot out by two nozzles just behind the wearer’s shoulders.

Called the JetLev-Flyer, the German design can purportedly reach a height of 50 feet, a speed of 45 mph and — wait for it — a range of 300 kilometers, or 186 miles, based on four hours of flying time.

Want one? They’re taking orders here, but be ready to shell out 100,000 euro, or $130,000 at today’s exchange rates.

Source

February 4, 2009

Telescope Sees Smallest Exoplanet

Filed under: Exoplanets, Life — bferrari @ 10:46 am

BBC

When planets transit their star, they block out light - like Mercury above

When planets transit their star, they block out light - like Mercury above

The smallest planet yet found outside the Solar System has been detected by a French space telescope.

The rocky world is less than twice the size of Earth.

Only a handful of planets have so far been found with a mass comparable to Earth, Venus, Mars or Mercury.

The discovery was made by Corot, an orbiting observatory with a 27cm-diameter telescope to search for planets orbiting other stars.

About 330 of these “exoplanets” have been discovered so far. But most of them have been gas giants similar to Jupiter or Neptune.

“For the first time, we have unambiguously detected a planet that is ‘rocky’ in the same sense as our own Earth,” said Malcolm Fridlund, Corot project scientist from the European Space Agency (Esa).

“We now have to understand this object further to put it into context, and continue our search for smaller, more Earth-like objects with Corot,” he added.

The new find, Corot-Exo-7b, orbits its Sun-like star once every 20 hours.

Because the planet is so close to its parent star, its temperature is between 1,000 and 1,500C – far too hot to support life.

Rock vs gas

The vast majority of exoplanets have been discovered using the radial velocity method.

This looks for spectral signs that a star is wobbling due to gravitational tugs from an orbiting planet.

But the method favours the detection of large planets orbiting close to its parent star.

Astronomers detected the new planet as it crossed the face of the distant “sun”, dimming the star’s light as it passed in front. This is known as the transit method.

Ian Roxburgh, professor of astronomy at Queen Mary, University of London, said the transit method still favoured the detection of big planets, because they blocked out more light from the parent star.

But he added that if you had a small star – as this one is – then a moderate-sized planet would block out enough light to be detected by telescopes.

Professor Roxburgh told BBC News there appeared to be another planet orbiting the same “sun” – a Neptune-sized gas giant.

Advanced science instruments aboard future spacecraft, such as the proposed European Plato mission, could find many more Earth-mass planets orbiting Sun-like stars.

The Corot mission is led by the French space agency (CNES), with contributions from Esa, Austria, Belgium, Germany, Spain and Brazil.

Its main objectives are to search for exoplanets and to study the interiors of stars.

Source

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