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Messenger, the Mercury-bound spacecraft NASA launched last August to explore the solar system's first planet, has delivered an unexpected gift.


On May 11, it snapped a fascinating picture of the Earth and the Moon. The shot, taken from some 18.4 million miles away, is a wonderful exhibit of the huge distance between us and our rocky satellite. The image comes as a surprise, considering that a full moon hanging over the horizon often looks like you could hit it with a rock.
In this picture, the distance between the Moon and the Earth is some 400,000 kilometers (248,000 miles), putting the Moon near its apogee at 405,000 kilometers. Apogee is the maximum distance the moon can reach away from the Earth. (The minimum distance, called perigee, is 363,000 kilometers.)
Expect more shots to come. Messenger will keep snapping away, testing its instruments, until August, when it's due for a fly-by around the Earth. Our planet's gravity will sling it towards Venus and then on to Mercury, which it will keep studying until 2011.

NASA says that most of the iron in ancient galaxies anchored by supremassive black holes have been forged when the universe was still young.



NASA's Chandra X-ray observatory studied spectra from 300 supermassive black holes in the centers of distant galaxies some 9 billion and 11 billion light years away. The peaks in the spectra produced by X-ray emission from iron atoms showed that approximately the same amount of iron was present in both sets of the holes. "This implies that most of the iron in the galaxies that contain these supermassive black holes was created before the Universe was about 2 billion years old, when galaxies were very young," NASA said. "The amount of iron around black holes has not changed significantly over the past 11 billion years."
The black hole in the center of our home galaxy holds a mass equal 4 million suns. It is estimated to be about 14 million miles (23 million kilometers) across, fitting within the orbit of Mercury around the sun. Since the Milky Way is estimated to be 13.6 billion years old, born just 200 million years after the "Dark Age" that succeeded the Big Bang, Chandra observartions may apply to our own iron. Something to think about when you next order spinach.

Scientists from the University of Arizona operating the Cassini spacecraft have been able to get some stunning surface pictures of Saturn' s perpetually clouded moon Titan.


But they've been baffled by a mysterious orange-colored spot near the moon's equator.
Members of the Cassini team have guessed that the 300-mile wide area might be a wound from a recent asteroid strike, or that the orange bruise is a mixture of water ice and ammonia oozing out of an ice volcano.
If that's the case, the spot might be a great place to start looking for extraterrestrial life.
In many ways, Titan, the second largest moon in the solar system after Jupiter's Ganymede, resembles the Earth some four billion years ago. It's the only known moon with a fully developed, planet-like atmosphere rich in nitrogen and methane. Such chemical brew could support the assembly of long organic molecules, similar to those, which preceded early RNA and DNA.
However, for life to be possible the moon "would need liquid water, which is not stable for long because Titan is too cold," said the Cassini scientists. (Titan's surface temperature averages -289F (-178C).) But "many of the large icy moons in the outer solar system host active water volcanism. Most of them contain a lot of liquid water, which flows across their surfaces in the same way lava does on Earth. Their internal heat initiates a melt that rises to the surface. These moons also contain various substances that are antifreezes (e.g. ammonia or formaldehyde). They are mixed into the water which lowers the density of liquid water and helps the water come up to the surface through the more dense icy crust."
Titan can also be heated with large asteroid impacts. "In the early 1990s, Carl Sagan and W. Reid Thompson of Cornell University suggested that impacts on the surface of Titan would melt the icy crust and produce liquid water," said Jonathan Lunine, professor of planetary sciences at the University of Arizona. He and a Russian colleague have been modeling impacts on Titan "to see what fraction of the crater would become liquid due to an impact." The couple computed that "an impact of a one-kilometer-diameter comet can turn about 5 percent of a crater's interior into liquid." Their simulations show that "the areas potentially containing organic matter would not be heavily shocked in an impact. Organic material survives such events and would be tossed in the crater where the liquid water would exist. When life on Earth originated about 4 billion years ago, large impacts were frequent."

Voyager 1, our messenger to the cosmic emptiness that lifted off the Earth in 1977, has reached the edge of the solar neighborhood.


The spacecraft "entered the solar system's final frontier, a vast, turbulent expanse where the Sun's influence ends and the solar wind crashes into the thin gas between stars," NASA said today. Said Edward Stone, Voyager project scientist at the California Institute of Technology: "Voyager has entered the final lap on its race to the edge of interstestellar space."
MIT's John Richardson, the principal Investigator of the Voyager plasma science said that "the consensus of the team now is that Voyager 1, at 8.7 billion miles from the Sun, has at last entered the heliosheath, the region beyond the termination shock."
The termination shock, NASA explained, is "where the solar wind, a thin stream of electrically charged gas blowing continuously outward from the Sun, is slowed by pressure from gas between the stars. At the termination shock, the solar wind slows abruptly from its average speed of 300 to 700 km per second (700,000 - 1,500,000 miles per hour) and becomes denser and hotter."
Voyager 1 has an identical twin brother, Voyager 2. That craft was concieved as a back-up for Voyager 1, but actually lifted off a month earlier, are on different flight paths. Voyager 1 is traveling at a speed of 3.6 astral units per year. (Astral unit is the distance between the Earth and the Sun, or about 93 million miles.) Voyager 2 is about 6.5 billion miles away from the Earth and moving at about 3.3 AU per year.
NASA estimates that the spacecraft could remain functional until 2020.

NASA reported today that its Cassini spacecraft has obtained the most detailed look ever at Saturn's rings, including the B ring, which has eluded previous robotic explorers.


"All ring features appear to be populated by a broad range of particle sizes that extend to many meters in diameter at the upper end," said Dr. Essam Marouf, Cassini team member.
Marouf said in a NASA press release that "at the lower end, particles of about 5 centimeters (roughly 2 inches" seem to abundant in the outer rings.
NASA said that "the inner and outer parts of ring B contain rings that are hundreds of kilometers wide (hundreds of miles) and vary greatly in the amount of material they contain. A thick, 5,000-kilometer-wide (3,100-mile) core contains several bands with ring material that is nearly four times as dense as that of ring A and nearly 20 times as dense as that of ring C."
Cassini analyzed the rings by beaming radio signals through the rings to Earth. "Scientists then watch how the strength of the radio signal is affected as the signal passes through ring material," NASA said. "The denser a ring is, the weaker the signal received. The experiment helps scientists map the distribution of the amount of ring material and determine the ring particle sizes."
From edge-to-edge, the ring system is wider than the gap between Earth and the Moon. But the rings are only 30 meters thick, or 100 feet. This is the first of many such observations Cassini will be conducting over the summer.

Here's one last take on the MIT time travel convention.


It's been proposed that nobody from our future showed up not because they didn't want to or because humans do not exist in the future, but because they simply couldn't. They were prevented by the many worlds interpretation of quantum mechanics.
Here's how. The MWI basically says that there's an infinitely large set of universes called a multiverse. At every instant, the universe splits off an infinity of other universes. Each of these universes has a copy of every quark, electron and gluon of the original universe, but is completely independent. In a multiverse, anything is possible and everything happens. For example, in one splinter universe you are writing this blog and I'm the reader.
But here's the catch. Two copies of the same particle cannot exist in the same universe without violating the laws of quantum mechanics. Therefore, when time travelers from our future arrived at the MIT campus two weeks ago, the universe immediately sprouted a new branch and re-routed the visitors away from us before we had a chance to debrief them.
The MWI, which was first proposed by English physicist Hugh Everett III in 1957, had some powerful backers like Stephen Hawking and John Archibald Wheeler.
However, they both changed their minds. "It required too much metaphysical baggage to carry around," Wheeler told physicist Heinz Pagels, author of the Cosmic Code. Hawking invoked his "chronology protection conjecture," which states that although quantum particles like photons can theoretically travel in time, "the laws of physics conspire to prevent time travel by macroscopic objects." The chief obstacle here is the second law of thermodynamics, which says that entropy, the measure of messiness of a system, must be growing with time for any closed system, including the universe. Reverse time's arrow and you'll most likely violate this bedrock of physics.
Perhaps the most eloquent rebuttal of the multiverse theory comes from Pagels himself: "But isn't this multi-reality and superspace all a great fanstasy, which although not strictly ruled out by quantum theory, is not required by it? You speak of all those other worlds as if they were real, when in fact, it is only this world - the one we live in - that we can ever know."

Here's an update on the MIT time travelers's bash.

It didn't go so well. "Unfortunately, we had no confirmed time travelers visit us," the organizers said. "We may be doing a run of t-shirts if there's enough interest."
That leaves us with a disconcerting question. Maybe no time travelers arrived from the future because there will be no future. Maybe something really bad happens before we learn to shake the shackles of spacetime.
Which forces us to take solace in John Titor, the only self-indentified time traveler from the future to be living on Earth right now. He claims that he came back from 2036, using a time machine built by General Electric. If he's right, rejoice and start saving up for your time-traveling retirement cruise. Here's how you do it. Buy some GE stock. Now!

American scientists say they have solved the mystery of a missing Martian icecap.


Mars, like Earth, has two icy polar caps. While the north pole appears to a fairly ordinary specimen, the south pole is a "strange animal," said Jeffrey Barnes, a professor of atmospheric sciences at Oregon State University. The southern ice cap is tiny compared to its nothern brother, about ten times smaller. It is made of carbon dioxide ice, the same stuff that street corner ice cream vendors use to cool their popsicles. That's normal since Martian atmosphere is rich in carbon dioxide.
What's unusual is that this dry ice is sequestered away from the planet's south pole. The pole itself is in the "cryptic region" which doesn't appear to have any ice at all. "No one has been able to figure out why there is this peculiar distribution of ice deposits," said Barnes.
Until now. Analyzing images and temperature measurements from the Mars Global Surveyor probe and plugging the data into climate models, Barnes and his colleagues from NASA figured out that the south pole is covered by a three-fee deep lid of crystal clear ice that's completely transparent. "We basically think the cryptic region is a sheet on incredibly clear ice," said Barnes. "The reason for the low reflectivity is that the ground beneath it shows right through it."
The scientists think that unlike visible ice caps, which on Mars as well as on Earth accumulate during snowfall, the clear ice forms when the Martian carbon dioxide atmosphere reaches brutal -193 F, starts behaving like freezing molasses, and "condenses right on the ground and forms slabs of ice."

There were no more details today from NASA on the powerful gamma ray burst reported yesterday. NASA scientists speculated that the burst was the result of a merger of two orbiting black holes or neutron stars and telegraphed the birth of a brand new black hole. However, Caltech physicist Kip Thorne has written extensively on the topic. A passage from his Black Holes and Time Warps gives an idea of what may have happened:
"The holes' inspiral [motion] is slow at first, but the closer the holes draw to each other, the faster they move, the more strongly they radiate their ripples of curvature [of spacetime], and the more rapidly they lose energy and spiral inward. Ultimately, when each hole is moving at nearly the speed of light, their horizons touch and merge. Where there were two holes, now there is one - a rapidly spinning dumbbell shaped hole. As the horizon spins, its dumbbell shape radiates ripples of curvature, and those ripples push back on the hole, gradually reducing its dumbbell protrusions until they are gone. The spinning hole's horizon is left perfectly smooth and circular in equatorial cross section...
"By examining the final, smooth black hole, one cannot in any way discover its past history. One cannot discern whether it was created by the coalescence of two smaller holes, or by the direct implosion of a star... The black hole has no 'hair' from which to decipher its history."
This account spells trouble for astronomers trying to decipher what happened on May 9. They will have to pore over old photographs of the cosmic region and look for traces of black holes or neutron stars. The new bald black hole won't give up any clues. One great source of evidence would be gravitational waves. Unfortunatelly, LIGO, Laser Interferometer Gravitational Wave Observatory, which still pretty much in debugging mode, has nothing to report.

Based on data coming out of NASA today, the agency's Swift gamma ray observatory has seen for the first time the birth of a black hole. The Swift registered a short and extremely powerful burst of gamma rays on May 9. NASA scientists speculate that the explosion was caused by a collision of two older low-mass black holes or two neutron stars.
Gamma bursts are the most violent events in the universe. NASA said that the burst, numbered grb050509b, "appears to have occurred near a galaxy that has old stars and is relatively nearby, about 2.7 billion light years away from Earth. This is consistent with the theory that short bursts come from older, evolved neutron stars and black holes. In contrast, longer gamma-ray bursts tend to be in young, distant galaxies filled with young, massive stars, remnants of the early universe."
"We are combing the region around the burst with the Keck Telescope in Hawaii for clues about this burst or its host galaxy," said Shri Kulkarni, a gamma-ray burst expert from the California Institute of Technology.
The system's image comes from Joshua Bloom, gamma-ray researcher at the University of California, Berkeley.

The Orion Nebula, a dazzling cloud of stellar dust riddled with bullet holes of bright young stars some 1,500 light years away, may be the most rewarding sight for any a backyard astronomer. Yet beyond the beauty, there lays a secret. It turns out that nebula holds important clues about the formation of our solar system.
NASA's Chandra X-ray observatory just snapped pictures of 1,400 stars in the nebula, including 30 which resemble the early sun. The photos revealed that some of Orion's youngest stars, just 10 million years old, erupt regularly in huge stellar flares, which dwarf in size, frequency and energy any such electromagnetic burps expelled by our Sun.
But that may not have always been the case. NASA astronomers analyzing the pictures say that the Sun may have also pumped out powerful flares when it was still young and boisterous, some 4.6 billion years ago. If that's the case, such outbursts have probably shaped planetary distribution of our solar system. "Big X-ray flares could lead to planetary systems like ours, where Earth is a safe distance from the sun," said Eric Feigelson of Penn State University. "Stars with smaller flares, on the other hand, might end up with Earth-like planets plummeting into the star."
Feigelson and his colleagues said that violent X-ray flares can create turbulence when they strike planet-forming disk, blow away nascent planets like soap bubbles, and prevent planets from burning up inside young stars. "Although these flares may be creating havoc in the disks, they ultimately could do more good than harm," said Feigelson. "These flares may be acting like a planetary protection program."
NASA wrote in a press release that "about half of the young suns in Orion show evidence of planet-forming disks including four lying at the center of proplyds (proto-planetary disks) imaged by NASA's Hubble Space Telescope."

Researchers at the the Georgia Institute of Technology and the University of California at San Francisco can spot tumors by tagging cancer cells with tiny gold nuggets. The scientists have engineered gold nanoparticles that are strongly attracted to the "epidermal growth factor receptor," a protein that sticks out of the surface of many cancer cells. The scientists chose gold since it's extremely efficient at absorbing and scattering light, making tumors glow like cities at night. "You can tell with a simple microscope that the whole cancer cell is shining," said Mostafa El-Sayed, director of the Laser Dynamics Laboratory and chemistry professor at Georgia Tech. "The healthy cell doesn't bind to the nanoparticles specifically, so you don't see where the cells are. With this technique, if you see a well defined cell glowing, that's cancer."
El-Sayed and his team reported that "the gold nanoparticles have 600 percent greater affinity for cancer cells than for noncancerous cells." They tested the technique using cell cultures of two different types of oral cancer and one nonmalignant cell line.
El-Sayed said that the new method is not toxic to humans and allows doctors make fast and detailed cancer observations with just a basic lab microscope. "If you take cells from a cancer stricken tissue and spray them with these gold nanoparticles that have this antibody you can see the results immediately. The scattering is so strong that you can detect a single particle," said El-Sayed.
This is not the first time researchers used gold to blow cancer's cover. Two years ago esearchers at Northwestern University developed gold marking and detection systems for breast and prostate cancer as well as many other types of cancer.

Russian astrologer Marina Bai is suing NASA over its Deep Impact mission designed to drive a spacecraft inside the Comet 9P/Tempel 1 on July 4. Bai, who's asking for $300 million, says that impact will disrupt the "natural balance of the Universe."
More strangely, a Moscow court actually took up the case.
A hearing was scheduled for May 6. So far now news on how it went.
The Deep Impact probe will crash a 39-inch spacecraft hauling some 700 pounds of copper into the 4-mile wide Tempel 1. The space craft will swoop down at a speed of 6.3 miles per second. The cosmic crash will take place 83 million miles away from Earth. NASA said that "the crater produced by the impact could range in size from the width of a large house up to the size of a football stadium and from 2 to 14 stories deep. Ice and dust debris will be ejected from the crater, revealing the material beneath."
The guts of comets are made of ice, gas and dust left over from the formation of the solar system 4.5 billion years ago and stored in a cosmic freezer beyond th orbit of Pluto. They hold important evidence about the birth and growth of Earth and other planets.

Military insignia of a purported American time traveler John Titor


MIT is holding "the first and only" Time Traveler Convention this Saturday, May 7. (That's right, one is all you need since you can always come back.)
Leaving nothing to chance, the entirely serious event gives precise directions for all those arriving from the future, or the past: East Campus Courtyard, MIT, 42:21:36.025 N, 71:05:16.332 W.
All time travelers are required to bring "some sort of proof that you do indeed come from the future, and haven't just dressed like you do. We welcome any sort of proof, but things like a cure for AIDS or cancer, a solution for global poverty, or a cold fusion reactor would be particularly convincing as well as greatly appreciated."
The organizers admit that they not at all sure whether time travel is at all possible. However, they are quick to ad that " the ancient Greeks would have thought computers were impossible, and the Phoenicians certainly wouldn't have believed that humans would one day send a spacecraft to the moon and back. We cannot predict the future of science or technology, so we can only make an effort and see if any time travelers come to our convention."
Sadly, only astralavista readers with time machines can take advantage of this post, tunnel back and sign up. MIT has already shut down registration "due to the overwhelming response."

Czech and American scientists have discovered the navigation gear that steers monarch butterflies on their annual pilgrimage from the north of the United States to Mexico. It's been known that the miniscule machinery resides in the monarch brain and guides the insect by analyzing the angle of polarized ultraviolet sunlight. But the researchers found that the key to the system is a link between the insect's eye and the brain region that holds the circadian clock circuits. The link, which the scientists spied by using tracer molecules illuminating circadian neural fibers connected to polarization photoreceptors in the eye, allows the butterflies compensate its position and flight path for the time of day. "This pathway has not been described in any other insect, and it may be a hallmark feature of butterflies that use a time-compensated sun compass," the researchers wrote. Since the link also supplies the brain with information about daylight, the scientists speculate that it might launch the monarchs's autumn migration. "The decreasing length of the day in the fall appears to be an important determinant for stimulating migratory behavior in butterflies," they said.
Of course, they went on to test their discovery and placed UV interference filters over the polarized light source simulating the sun in the lab. Sure enough, the poor monarchs got lost.

Scientists at Jefferson Medical College in Philadelphia have grown tobacco plants producing cancer fighting chemicals called monoclonal antibodies, which latch onto tumors and kill them like heat-seeking missiles. They are hoping that tobacco plants may soon become "antibody factories" producing proteins pounding variety of cancers.
The vegetal medicine seems to work. Results from animal trials show that the harvested antibodies attacked human colorectal tumors grown on mice and halted their growth. "The antibody produced in tobacco is as good as the antibody produced in animal cells," said Hilary Koprowski, professor of microbiology and immunology at Jefferson. She said that tobacco-derived antibody should be safer and less expensive to produce than antibodies currently grown in mice. The school says it is now looking for industry partners to begin mass production.
This is not the first time Jefferson scientists used tobacco to grow medicine. In the past they harvested rabies-fighting antibodies, which stopped the disease in infected mice.
Koprowski is already moving ahead with more research, testing new kinds of tobacco-grown antigens on breast and lung tumor cells.

The 15-year old Hubble Space Telescope, the workhorse space camera that snapped 700,000 pictures of the farthest and most violent corners of the universe, is dying. If nothing is done, its batteries and altitude control gyroscopes are going to fail within the next two or three years, leaving it crippled and unable to do any research.
Today there's little hope for a fix. The Bush White House seems to be ready to pull the plug on the Hubble, saying it wants to go to Mars instead. NASA says that servicing the Hubble from the the International Space Station would be too dangerous.
No wonder that the Space Telescope Science Institute in Baltimore, Maryland, which runs the telescope is appealing for clemency directly to the public. Doing what it does best, it released some stunning images of the universe. Take a look. The cosmos is frightening and awesome. Somehow, we also fit in.

A new study published by NASA, Columbia University and the Lawrence Berkeley National Laboratory says that Earth's energy is "out of balance," pointing out that the "energy imbalance is large by standards of the planet's history." The report said that more heat is being absorbed from the Sun than is emitted back to space, causing global warming.
Though hardly surprising, the finding is quite juicy, given that the study was partly funded by American tax dollars and published by a U.S. government agency. The Bush administration has steadfastly dismissed global warming as greenie hubris and refused to join the Kyoto protocol drafted to cut emissions of greenhouse gasses.
The scientists led by NASA's Jim Hansen gathered 10 years of climatic records from satellites and buoys, and used computer models to study the Earth's oceans. "The energy imbalance is an expected consequence of increasing atmospheric pollution, especially carbon dioxide, methane, ozone, and black carbon particles," said Hansen. "These pollutants block the Earth's heat radiation from escaping to space, and they increase absorption of sunlight."
The scientists wrote that the imbalance between absorbed and radiateed heat is 0.85 watts per meter squared. "That will cause an additional warming of 0.6 degrees Celsius (1 degree Fahrenheit) by the end of this century," they said. "To understand the difference, think of a one-watt light bulb shining over an area of one square meter (10.76 square feet). Although it doesn't seem like much, adding up the number of feet around the world creates a big effect. To put this number into perspective, an imbalance of one-watt per square meter, maintained for the past 10,000 years is enough to melt ice equivalent to one kilometer (.6 mile) of sea level, if there were that much ice."