At least five Earth-sized planets appear to be orbiting their stars at just the right distance to host liquid water, NASA said Wednesday, announcing a significant step in the agency’s search for extraterrestrial life.

The Kepler telescope gleaned an extraordinary amount of new information in less than two years of Earth orbit, observing a small slice of the Milky Way galaxy.

The discoveries include whole solar systems and planets close enough to each other to give scientists clues about what they are made of — thus how hospitable to life they may be.

“Not only is Kepler telling us about planetary systems of a type that we had no idea existed, but right now it’s providing our best clues on the composition of these planets as individual worlds,” Kepler scientist Jack Lissauer said Wednesday at a briefing to announce the discoveries.

Several hundred new “planet candidates” — they are, for now, just known to be celestial bodies — bring the Kepler mission discoveries to 1,235 possible planets, potentially tripling the count of extra-solar planets from the current 519.

Of those bodies, 68 are about the size of Earth, and five of those Earth-sized bodies were observed in what scientists call the “habitable zone,” where liquid water could exist on a planet’s surface.

“If we find that Earth-sized planets are common in habitable zones of stars, it’s very likely that life is common around these stars,” Kepler scientist William Borucki said Wednesday.

Before Wednesday, there were only thought to be at most two extra-solar planets in their system’s habitable zone.

Another 49 planet candidates were found by Kepler in the habitable zone, but their enormous sizes suggest big, gassy planets more like Saturn, which, regardless of their distance from their star, cannot sustain life.

The Kepler mission has also turned up 170 stars that appear to be orbited by multiple planets. Such systems are crucial because the planets’ effects on one another’s orbits allow scientists to glean more information about their environments.

“We’re studying systems of planets,” Mr. Borucki said, describing multiplanet systems as “the most valuable things that we can find.”

The largest such system so far has six planets orbiting a star dubbed Kepler-11.

“The five inner planets are essentially close together, something that we didn’t think would happen for worlds of this size,” Mr. Lissauer said. The planets’ proximity means they are disturbing one another’s orbits enough to determine what they might be made of, he said.

The inner two possible planets of this system could be mixtures of rock and water or rock and gas, while the outer planets are large for their mass and must be made of large parts hydrogen and helium, Mr. Lissauer said.

Such a pattern would be similar to our solar system, which has four small, rocky “inner planets” (Mercury, Venus, Earth and Mars) and four large, gassy “outer planets” (Jupiter, Saturn, Uranus and Neptune).

However, our own solar system also suggests limits to Kepler’s discoveries. For example, Mars and Venus are on the edge of our solar system’s habitable zone and even have water (if not in liquid form), but neither has known living beings. Also, being hospitable to life doesn’t necessarily mean hospitable to intelligent life, but possibly just to simple forms such as bacteria.

Kepler cannot determine whether these planets do have the kinds of atmospheres and carbon contents necessary for advanced life forms.

Still, Yale University astronomy professor Debra Fischer said the system orbiting Kepler-11 is an enormous discovery.

“It shows that planetary systems with several small planets like our own seem to be common,” she said. “The adjacent neighborhoods in the galaxy look a lot like our own neighborhood. I think that’s encouraging and important if we’re trying to make extrapolations about the formation of planets elsewhere and perhaps life.”

Ms. Fischer said she is amazed at the number of possible planets — especially Earth-sized planets — the mission has discovered since the orbiting observatory was launched in March 2009. She had expected the discoveries to come in slower, over the course of years.

“Kepler’s blown the lid off of everything we know about extra-solar planets,” she said.

The Kepler observatory uses a telescope that measures light to monitor the brightness of more than 156,000 stars. Orbiting planets block some of that light, causing stars to appear to dim at regular intervals.

The telescope remains constant over the same small patch of sky, about a four-hundredth of the total sky.

This batch of data has undergone only preliminarily analysis and, now that the entire astronomical community has access to it, it is expected to turn up many more discoveries, especially some refining our understanding of Wednesday’s data.

“The stars that surround us have a huge number of planets and candidates for us to look at,” Mr. Borucki said. “Kepler is a step in the exploration of the surrounding galaxy to find life and the extent of life in our galaxy.”

If dinosaur evolution were an Austin Powers movie, T. rex would be Dr. Evil. And today scientists unveiled Mini-Me.

But in this case, it was the tiny terror that gave rise to the larger, fiercer relation.

Raptorex kriegsteini, described this week in the journal Science, likely lived about 125 million years ago, during the Cretaceous period.

That’s almost twice as far back as the mighty Tyrannosaurus rex, according to study leader Paul Sereno of the University of Chicago.

Raptorex has all the main characteristics of its larger descendants such as T. rex—big head, nipping teeth, stubby arms, fast legs—but packed into a 9-foot (3-meter) frame.

This T. rex design in miniature “reveals a spectacular carnivore strategy,” according to Sereno, a National Geographic Society explorer-in-residence. (The National Geographic Society owns National Geographic News.)

Tiny T. rex “Evolutionarily Staggering”

The 150-pound (70-kilogram) Raptorex “was running things down, dispatching them with its powerful jaws, and clutching them with its two-fingered hands”—the same hunting strategy that apparently worked for 6-ton T. rex, Sereno said.

“That’s the pretty evolutionarily staggering thing,” he added. Raptorex is T. rex, but “scaled up, almost without change, a hundred times.”

The find runs counter to previous theories, which had said that T. rex’s stumpy arms were a relatively recent evolutionary development. As tyrannosaurs got larger, their arms simply didn’t scale up fast enough, and the limbs eventually became small in relation to the dinosaurs’ oversized bodies, the older theories say.

It’s still thought, however, that T. rex’s earlier ancestors—even before Raptorex—had relatively long arms.

T. rex-style Arms Not a Liability

The new dinosaur is “a very significant find” for understanding the evolution of tyrannosaurs, said paleontologist Thomas Holtz of the University of Maryland.

“We didn’t know where and when in the history of the tyrannosaurs this arm-shortening occurred,” said Holtz, who was not part of the study.

“Now the question is going to be, What were they doing [with those small arms]?” Holtz said. “There’s not much of a reach,” he added, speculating that the tyrannosaurs grabbed prey first with their jaws and then used their arms to help hold onto their quarry.

Study leader Sereno noted that it can be hard for people to appreciate the trade-offs that evolution inevitably entails.

“It would seem to a human that forelimbs are so useful, that only when you got to the size of a tyrannosaur and you could frighten everybody with a growl could you get rid of [forearms],” he said.

“But this common sense type of thinking almost never works with evolution,” Sereno said. In the tyrannosaurs, for instance, “long, heavy forelimbs are a significant burden and would seriously curtail agility in the hunt.”

Smuggled T. rex Ancestor Heading Home

The new findings are based on a nearly complete Chinese dinosaur skeleton, which was excavated in secret, smuggled into the United States, and sold at auction to private collector Henry Kriegstein.

Sereno said he convinced Kriegstein to donate the fossil back to science.

Although the exact location the dinosaur came from will never be known, the excavated block containing the dinosaur’s skeleton also included fish bones and clamshells that link it to Northern China’s Yixian fossil formation.

Raptorex kriegsteini, named after the collector’s father, an Auschwitz survivor, will eventually be shipped back to Northern China, where it will be displayed in a museum in Hohhot, the capital of China’s Inner Mongolia region.

“Fossils like these should be protected from smugglers, or there’s a chance they could disappear forever,” Sereno said.

Until that day comes, Sereno hopes the story of this fossil can serve as a model for saving—and learning from—smuggled dinosaurs.

“I think everybody involved with this Raptorex is a winner here,” he said.

A total solar eclipse passed over some of Earth’s most densely populated regions today (pictures of today’s total solar eclipse).

Just before daybreak the solar eclipse began over India and was widely visible across Asia before darkening southern Japan and finally ending over the Pacific Ocean.

Lasting as long as 6 minutes and 39 seconds in some areas, the solar eclipse boasted the longest period of totality—when the sun appears to be completely blotted out by the moon—of the entire 21st century.

Today’s record eclipse, though—if you include the periods where the sun was only partially covered—will be eclipsed by another total solar eclipse in 2132.

Solar Eclipse Science

At a remote hotel at an altitude of about 3,000 feet (900 meters) on Tianhuangping, a mountain outside the Chinese city of Hangzhou, solar eclipse scientist Jay Pasachoff witnessed the July 2009 solar eclipse with other scientists and enthusiasts from around the world.

“We saw it! The clouds kept getting thinner, and we even had a pretty good-sized hole in the clouds for the five minutes of totality, said Pasachoff,” chair of the International Astronomical Union’s Working Group on Solar Eclipses, in a blog entry.

The roughly five and a half minutes of total solar eclipse seen from Tianhuangping was the longest period of totality visible from the Asian mainland.

From a scientific perspective, “once you have five minutes-plus of totality, the extra minute that we could have [seen from the Pacific] is not significant,” Pasachoff, of Williams College in Massachusetts, told National Geographic News earlier this month. Those few minutes should have provided enough data to keep his team busy for months, he said.

Solar Mystery

Pasachoff studies solar eclipses in part to figure out why the sun’s corona—gas that extends millions of miles out from the sun—is millions of degrees hotter than the sun. The sun’s temperature is just about 6,000 degrees Fahrenheit (3,300 degrees Celsius).

“Somehow energy has been put up into the corona from lower down, heating the gas, and we’d like to see how that happens,” he said.

Scientists believe the coronal phenomenon has to do with the sun’s magnetic field, and Pasachoff is looking to identify vibrating magnetic waves that move from the sun out into the corona.

(Related: “‘Corkscrew’ Waves Seen on Sun — Keys to Solar Mystery?”)

Scientists can’t usually see the corona from Earth because its light is fainter than the blue sky created by our atmosphere.

Furthermore, instruments attached to space satellites can’t isolate all areas of the corona because the sun and the light it scatters are too bright.

The only time certain observations are possible is during a solar eclipse, when the moon blocks out the sun, creating a darker sky, which highlights the coronal light around the sun.

(Find out some of the ways eclipse chasers have advanced science, from proving Einstein’s theories to finding “other Earths” outside the solar system.)

Although the sun is about 400 times bigger than the moon, it’s also about 400 times more distant. So from the ground, the moon appears to be just a little bigger than the sun—exactly what happened as the clouds parted over Tianhuangping earlier today.

“Everyone saw all the coronal phenomena,” said Pasachoff, a National Geographic Society Committee for Research and Exploration grantee.

The distinct, jewel-like bursts of light just before and after the total solar eclipse were a highlight, he added. “The diamond rings were spectacular [picture of a solar eclipse diamond ring]. Just before totality, the clouds were just the right thickness that allowed us to see partial phases without filters.”

“All our equipment seems to have worked, so now we still have an hour or so of partial eclipse to image, and then we will download photos and start looking at them,” Pasachoff said by email from China, according to a statement.

(See some of Passachoff’s pictures of the July 22 total solar eclipse.)

Eclipse Chasers

The sun’s disappearing act attracts so-called eclipse tourists, who travel the world to watch solar eclipses, which happen between two and five times a year, though total solar eclipses are less frequent.

(See solar eclipse pictures.)

Rollie Anderson, a retired actuary from St. Louis, Missouri, is in China today, on a trip planned around the solar eclipse, his 14th.

“The cosmic coincidence that the sun and moon both appear in the sky as the same size, and then, on top of that, they line up every now and again. … Just the very idea of that is pretty mind-blowing,” he told National Geographic News earlier this month.

“As you get to the last several minutes before totality, that’s when your eyes actually start noticing things getting dark around you, and you can feel the air cooling,” he said. “It gets really dark and totality appears, and that’s when it gets most spectacular.”

“You see a black hole in the sky where the sun used be, and if there are birds around, they may stop chirping, because they think it’s night.”

Chasing eclipses has also allowed Anderson and his wife to see the world.

“It’s kind of an excuse to see whatever the part of the world the eclipse happens to be in.”

Merging galaxies that forcefully eject supermassive black holes have theoretically created a whole new class of astronomical object—and now scientists think they know how to find them.

Black holes that get kicked out should carry with them clusters of nearby stars, a new study says.

These stars can act as signposts and can reveal details about the now galaxy-less black hole’s past life.

In theory, hundreds of massive black holes left over from the age of galaxy formation could be lurking in the nearby universe.

“Every such black hole that’s ever been kicked out is still potentially observable, and that’s very encouraging,” said lead study author David Merritt of the Rochester Institute of Technology.

“It’s not quite what anybody has seen so far,” he said. “We’re just talking about what they would look like if you were to find them.”

Observations made with the Hubble Space Telescope and re-examined with ground telescopes have come close, Merritt said.

“People are now just starting to make the kind of observations to see these kinds of things, if they are there.”

Powerful Kick

Most galaxies are thought to harbor black holes at their centers that are millions to billions of times the mass of our sun.

When galaxies merge, their respective supermassive black holes start to coalesce in a process that creates a spurt of gravitational waves.

If the waves are strong enough, the kick they provide should drive the newly merged black hole outside the host galaxy, simulations from the past few years suggest.

That kick would also leave the “rogue” black hole surrounded by any orbiting stars that got taken along for the ride, Merritt and colleagues report in the July 10 issue of the Astrophysical Journal.

(Related: “New Class of Black Hole Found?”)

And knowing the speed of the stars that accompanied the black hole can reveal the speed of ejection, Merritt said.

That’s because stars that were orbiting slower than the force of the kick would stay in the host galaxy.

“[It's] like the sun in our solar system: If you gave it a kick, it would take along some of the inner planets, like Mercury, but it would leave behind the outer planets because they’re just too weakly bound to the sun to move with it,” Merritt said.

Milky Way’s Mergers

Scientists earlier this year came to similar conclusions in a study that focused on our home galaxy, the Milky Way.

“The Milky Way is thought to have been a collection of small galaxies early on that later merged together,” said Avi Loeb of Harvard University, a co-author of the paper, published in the April issue of the Monthly Notices of the Royal Astronomical Society.

“If this [merger] process took place at each stage of evolution, then black holes would have escaped from the merger remnant but would have still been [surrounded by nearby stars],” he said.

Both new theories are reasonable, based on estimates made in the last few years of how strong a merging black hole’s kick might be, said Christopher Reynolds, of the University of Maryland in College Park.

“The question is if that actually does happen in nature,” said Reynolds, who was not involved in either study.

Merritt’s work is “good science in the sense that it lays out a very clear path by which we can actually use observations to address these questions,” Reynolds added.

“If we don’t find [the black holes with star clusters], that could tell us that the estimates of how many of these black holes get ejected with very high velocity are off.”

The Mississippi River Delta is drowning, according to new research that predicts the surrounding coastline will be inevitably reshaped in coming decades.

“There’s just not enough sediment to sustain the delta plain,” said study author Michael Blum.

Deltas are coastal landmasses created from a river’s sediment deposits as the water flows out to sea.

The Mississippi River’s delta plain, for example, includes the lacy “toe” of southern Louisiana. (See a Louisiana map.)

All deltas are degrading to some extent, as their sediment settles and sinks. But a delta can sustain itself or even grow if its parent river regularly deposits enough new material.

Today sediments collected along the Mississippi cover about 23,360 square miles (60,500 square kilometers) ranging in thickness from less than 33 feet (10 meters) upstream near Memphis, Tennessee, to about 328 feet (100 meters) in the delta at the tip of southern Louisiana.

The drainage basin of the roughly 2,350-mile-long (3,782-kilometer-long) river, however, includes about 40,000 dams and levees built over the past century.

These structures control flooding and improve navigation, but they also trap sediment or funnel it completely through to the sea.

Previous studies suggested that dams and reservoirs built since 1950 have trapped as much as 70 percent of the river’s natural amount of sediment. With less material feeding it, the delta plain has been experiencing erosion.

(Read a National Geographic magazine article about erosion in Louisiana that seemed to “predict” the damage done by Hurricane Katrina.)

But even without the dams and levees, the amount of sediment flowing downriver would no longer be enough to sustain the delta because of rising seas, the study authors say.

Tough Choices

The researchers base their conclusions on estimated delta levels over the past 12,000 years, which show significant changes more than 7,000 years ago, when meltwater from the last ice age quickly filled the oceans.

The Mississippi Delta plain retreated inland at that point, and it was only after sea level rise had slowed considerably that the delta again grew seaward.

Current sea level rise, however, may be three times faster than it was the last time the delta was able to grow. (Related: “New York, Boston ‘Directly in Path’ of Sea Level Rise.”)

With the added threat of rapid sea-level rise, sustaining the current extent of the delta plain would require 18 to 24 billion tons of sediment—way more than the entire Mississippi River currently carries, the researchers say.

The team therefore estimates that as much as 5,200 square miles (13,500 square kilometers) of delta land could disappear by 2100—an area only slightly smaller than Connecticut.

For now the study authors don’t have a solution, and they add that plans to save the delta plain—such as redirecting and possibly adding sediment—will almost certainly involve sacrifices.

“They can [divert sediment to areas] downstream from, say, New Orleans, but that means that areas [of the delta plain] farther upstream will be submerged,” Blum said.

“Tough choices have to be made, and they need to be made fast.”

After five successful spacewalks that have left the Hubble Space Telescope more capable than ever, astronauts on the space shuttle Atlantis held a space-based press conference today.

(See “Shuttle Crew’s Repairs Will Leave ‘Best Hubble Ever.’”)

The crew recounted the mission’s unexpected obstacles, advocated for human exploration of space, and turned their eyes to new frontiers—before they’d even returned to Earth.

“In human space flight, as much as we love lower-Earth orbit, it’s time to leave lower-Earth orbit and go out and explore the cosmos,” veteran spacewalker John Grunsfeld said.

Hugs for Hubble

Grunsfeld and fellow crew member Andrew Feustel, who was on his first space mission, were the last humans to work directly on the orbiting observatory. No more manned servicing missions are scheduled or likely.

“We both gave Hubble one last hug before coming inside,” Grunsfeld said. “We knew that [crew member Megan McArthur] was going to be the one to hold Hubble the last time and send it on its way.”

Operating a robotic arm from inside the shuttle, McArthur had let go of the satellite on Monday morning, and Atlantis slowly pulled away (see video below).

The mission successfully installed two new science tools, fixed two ailing ones, and replaced batteries and gyrators. But there were definitely hiccups along the way.

For instance, veteran astronaut Michael Massimino struggled to remove the last of 117 screws on one of the science instruments’ handrails during a repair—the screw that had always been the easiest during his practice sessions on Earth, he said.

“What was really most challenging for me was not to give up hope that we could do it,” Massimino said.

Humans vs. Robots

Grunsfeld said such incidents demonstrated “the extreme utility of having people working in space and accomplishing things that are different than what was expected.”

His comments are an indirect response to calls to replace expensive and dangerous manned missions and spacewalks with robotic missions.

“As we push further out, from lower orbit to the moon, Mars, and beyond, we’re going to have to do this kind of work every single day,” he said.

Not before some hard-earned rest, however.

“We’ve been training for this flight for a couple years now,” McArthur said. “We all feel pretty good about what’s been accomplished, but we’re also looking forward to taking a break.”

The seven-member crew is also looking forward to a call this afternoon from U.S. President Barack Obama—and to returning to Earth on Friday, when the predicted weather conditions should provide for a smooth landing.

Thousands of miles above Earth, a cosmic chorus is filling the heavens with a mysterious, low frequency “hiss.”

That’s the conclusion of scientists studying data from a set of NASA probes designed to monitor substorms—dramatic exchanges of energy among charged particles that spark the auroras at Earth’s poles.

The charged particles come from the sun and get trapped in loops around our planet by Earth’s magnetic field.

Knowing how the hiss influences the loops, known as Van Allen radiation belts, might help scientists predict their behavior—a good thing, because the belts can bombard satellites, spacecraft, and even spacewalking astronauts with dangerous radiation.

Although we’re currently experiencing an unprecedented lull in solar activity, space is expected to get much stormier after 2012, when the sun should enter an active phase that will hurl more charged particles toward Earth.

Lucky Break

The faint “shh” sound that scientists now call the plasmaspheric hiss is the result of an electromagnetic wave in Earth’s radiation belts.

The hiss wave appears to reduce levels of dangerous electrons in the radiation belts by deflecting the particles from their stable trajectories and sending them into the dense upper atmosphere, where they are lost.

For more than four decades scientists have been puzzled by what was generating the hiss wave, noted study leader Jacob Bortnik, of the University of California, Los Angeles.

A previous model had suggested that the hiss wave might evolve from a more distant radio wave called chorus, so named because its discoverers in the 1950s thought it sounded like “a rookery of birds heard from a distance,” Bortnik said.

But proving this idea presented a challenge. Researchers would need simultaneous, high-resolution observations from two sophisticated satellites recording both hiss and chorus from different locations at a moment when Earth’s magnetic field was particularly active.

By chance, one of Bortnik’s students found exactly what they needed in data from two of NASA’s five THEMIS satellites.

“We didn’t think that we’d be lucky enough to get this kind of gift from nature,” Bortnik said.

The probes showed a definite correlation between the two waves, confirming that the hiss wave comes from chorus.

Weather Forecasts

Understanding the hiss wave’s origins could allow scientists to build more accurate models of the radiation belts, which could ultimately help predict space weather.

Studying space weather, Bortnik added, is similar to studying weather patterns here on Earth.

“Step number one is just to understand the system,” he said, and then maybe there’s hope that researchers can predict things in time to avoid danger.

Findings published this week in the journal Science.

The ever-present supersonic gale from the sun creates never-before-seen magnetic “twisters” that “dance” across Mercury’s magnetic field and occasionally touch down on its surface, new observations have revealed.

These invisible formations, made of high-energy electrons, kick up material from Mercury’s surface and send it flying into the tiny, rocky planet’s tenuous atmosphere, according to new research.

Part of a suite of new findings based on October 2008 data from the MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and Ranging) spacecraft, the study could help explain why Mercury’s thin, inconstant atmosphere is so, well, mercurial.

The findings, published this week in the journal Science, could also add to scientists’ understanding of the phenomenon called space weather.

With a period of strong solar storms predicted to start in 2012 that could interfere with satellites and disrupt power grids on Earth, better understanding of solar wind is a pressing need, scientists say.

(Related: “Magnetic-Shield Cracks Found; Big Solar Storms Expected.”)

Surprisingly Intense

Mercury’s magnetic twisters are created when solar wind—which is actually a stream of charged particles—triggers a process on the tiny planet called magnetic reconnection.

This is when magnetic field lines flowing from the sun splice together with the field lines around Mercury.

The connection transfers solar wind energy into the planetary magnetic field and sends charged particles shooting toward the planet along the field lines.

Bundles of these connected field lines then penetrate the planet’s magnetic boundary and their particles are sent whirling by the solar wind, forming the twisters.

On Earth, energy from magnetic reconnection “lights up” atoms in our much thicker atmosphere, creating the shimmering auroras at our planet’s poles.

(Related: “Giant ‘Space Tornadoes’ Spark Auroras on Earth.”)

What surprised scientists is that reconnection on Mercury is ten times more intense than it is on Earth, said study author James Slavin of the NASA Goddard Space Flight in Greenbelt, Maryland.

It’s reasonable to think that magnetic reconnection would be stronger on Mercury, the closest planet to the sun. But researchers were anticipating it would only be about two or three times more intense than on Earth, Slavin said.

Figuring out why the process is so much stronger than expected could shed light on how solar wind affects magnetic fields around other planets, including Earth.

Despite the stronger reconnection events, Slavin said, “at Mercury, we don’t have an atmosphere that’s dense enough or of the right kind of gas probably to produce anything we would recognize as auroras.”

Still, similar invisible currents may exist along those same magnetic regions of Mercury.

“It’s possible there may be a little ring around both poles of Mercury, where the surface is ever so slightly warmer than the other latitudes of the planet,” Slavin said. (See a photo of “hyper auroras” on Jupiter.)

Solar Erosion

The new observations also show that—like the twisters—the solar wind directly plays a part in shaping the mysterious planet’s surface.

Earth, Jupiter, and Saturn have dense atmospheres and strong magnetic shields, protections that deflect the full force of the winds from reaching their surfaces.

On Venus and Mars, meanwhile, there’re little or no magnetic fields but some atmospheres, so “there’s a tendency for the solar wind to strip away the atmosphere over the eons,” Slavin said.

(Related: “Stars Can Strip Gas Giants Naked.”)

“In the case of a body like Mercury, where you don’t have a planetary atmosphere, or you have an extremely tenuous one, you have a situation where the solar wind … actually erodes the surface somewhat. It’s a very small amount,” Slavin said.

Sean Solomon of the Carnegie Institution in Washington, D.C., who was involved in the research, noted that there was much more magnetic activity during the October flyby than during MESSENGER’s first encounter in January 2008. (See photos from the first Mercury flyby.)

“Mercury is a lot more complicated and its processes are a lot more dynamic than we knew,” Solomon said.

A giant space blob discovered in the far reaches of the universe has scientists puzzling over what exactly the bizarre object might be, according to a new study.

At 12.9 billion light-years away, the blob—dubbed Himiko after a legendary Japanese queen—is the fourth most distant object ever discovered, said lead study author Masami Ouchi, a Carnegie Institution fellow.

Because of the time it takes light from so far away to reach Earth, astronomers are seeing the blob as it was when the universe was just 800 million years old, about 6 percent of its current age.

But “the most significant feature of this object is the size,” said Ouchi, who describes the find in the May 10 issue of the Astrophysical Journal.

Himiko is about 55 thousand light-years across, or roughly the size of a mature present-day galaxy, making the young blob the earliest known object of its size.

(Related: “Giant ‘Blob’ Is Largest Thing in Universe.”)

In addition, the blob has an unusual structure: A large mass of stars sits its center, while the whole thing is shrouded by a mysterious cloud of electrically charged hydrogen.

According to Ouchi, Himiko could be some sort of primordial galaxy, but one that does not resemble other galaxies found during the so-called cosmic dawn.

Big Blobby Galaxy

Chris Carilli, chief scientist at the National Radio Astronomy Observatory in Socorro, New Mexico, said the study’s science is solid and extremely careful.

The find challenges prevailing theories that say very young galaxies should be much smaller, and that over time small galaxies merged to form the large ones we see today, he suggests.

(See pictures of unusual galaxy mergers.)

“I would be a little more risky and say that [the newfound blob is] pretty clear evidence for massive galaxies forming very early,” said Carilli, who was not involved with the study.

Richard Ellis, an astronomy professor at the California Institute of Technology, said Himiko could be a galaxy that is collapsing in on itself, a never before observed stage of galactic development.

Such a collapse would create an enormous burst of star formation, which would heat up the remaining hydrogen around the galaxy, creating a charged cloud like that seen around Himiko.

Alternatively, Ouchi suggested, the hydrogen cloud could be gases from the surrounding environment that are cooling and gravitating toward what is actually a mature galaxy inside Himiko.

But if the blob is a stable, mature galaxy at its core, astronomers should be seeing other similar galaxies from the same time period, Caltech’s Ellis noted.

“I much prefer the spectacular argument that we’re seeing an object at a very special time in its history,” he said.

Ouchi hopes to resolve some of these issues by solving the mystery of Himiko’s energy source, which he described as “the most difficult question.”

“It could be a supermassive black hole or the cooling radiation powered by gravitational energy or outflow from starbursts … ,” he said.

Understanding what’s driving the blob’s development should help determine what kind of object it is.

The trend could seriously threaten the area’s caribou and other wildlife, as well as local landmarks that document human settlements.

Some stretches of the state’s northern shore along the Beaufort Sea receded by more than 80 feet (25 meters) in summer 2007 alone, when Arctic sea ice was at a record low.

In the past, spurts of erosion had often been linked to storms, but there were no major storms in 2007. That suggests “a shift in the forces driving erosion,” said lead author Benjamin Jones, a research geographer at the U.S. Geological Survey.

One major force now is global warming, according to the research.

The study of the 40-mile (64-kilometer) stretch of coast was published this week in the journal Geophysical Research Letters.

Out to Sea

Warming air and sea temperatures are melting the ice in the region’s permafrost, or perpetually frozen earth. The meltwater then streams over the land and melts more permafrost, carrying sediment into the sea as it goes.

From 2002 to 2007, the melting ice caused the coast to disappear at a rate of about 45 feet (14 meters) a year.

That’s up from an annual average of 30 feet (9 meters) between 1979 and 2002 and 20 feet (6 meters) between 1955 and 1979.

Remains of the ghost town of Esook, a hundred-year-old trading post, have been buried underwater as a result of the erosion, Jones said.

And near the town of Lonely, Jones took a picture of a whaling boat that a few months later was swallowed by the sea after nearly a century on shore.

The erosion also threatens oil wells. At least one has already been lost since 2002, and another will soon be gone, if the melting continues at these rates.

Especially Vulnerable

Larry Hinzman, director of the International Arctic Research Center in Fairbanks, Alaska, said the permafrost in this region has a considerable amount of ice, which is one reason it is melting so fast.

“If it were a different soil type, it would have less ice and would not erode so quickly,” said Hinzman, who was not involved with the research.

Hinzman said the findings “would not be representative of the whole Arctic, but there are many places in the Arctic where the permafrost does contain similarly massive amounts of ice.

“This is not an unusual landscape feature in Alaska, Canada, or Siberia, but it would be unusual in Greenland, Iceland, and [the Norwegian archipelago] Svalbard,” he said.

The researchers call for more study of the erosion patterns so that preservation plans can be devised and new development can avoid early demise.

“Erosion is a natural process, and it is likely that this coastline has experienced erosion for quite some time,” Jones said. It’s the speed at which it is now occurring that worries researchers.