Cosmic bat

The reflection nebula NGC 1788 seems to spread gigantic dusty wings in a picture captured by the European Southern Observatory's MPG/ESO 2.2-meter telescope in Chile. The batwings are actually clouds of gas and dust that scatter light emanating from a cluster of young stars in the constellation Orion. This picture was released on March 3.

Story

Delicate nebula looks like a cosmic bat
A new photo of a nebula hidden near the constellation Orion reveals gas in the shape of a bat spreading its wings.

Winds of change

This composite image, released March 3, shows the spiral galaxy NGC 1068, which has a rapidly growing supermassive black hole at its center. X-ray readings from NASA's Chandra X-Ray Observatory are shown in red, optical emissions are in green, and radio emissions are in blue. The X-ray data suggest that a strong wind is being driven away from the galaxy's center at a rate of about a million miles per hour. These results help explain how an "average" supermassive black hole can alter the evolution of its host galaxy.

A strange land

Translucent ice formations dot the terrain in Mars' north polar region, as seen by NASA's Mars Reconnaissance Orbiter. Sunlight can shine through the ice to warm the surface below, creating weird shapes as the ice thaws. The image was acquired on Jan. 15 and released March 8.

Double-barreled blast

Two active regions glow brightly in this ultraviolet image of the sun, acquired by NASA's STEREO Ahead spacecraft on Feb. 12 and posted online March 20. A small flare rises from the active area on the left. Flares are intense solar explosions that blast radiation into space. This one paints a white line across the left edge of the sun's disk. Meanwhile, the active area on the right churns with magnetic loops

Out-of-control satellite threatens spacecraft

Galaxy 15 stopped responding to ground controllers on April 5

PARIS - An adrift Intelsat satellite that stopped communicating with its ground controllers last month remains out of control and has begun moving eastward along the geostationary arc, raising the threat of interference with other satellites in its path, Intelsat and other industry officials said.

In what industry officials called an unprecedented event, Intelsat's Galaxy 15 communications satellite has remained fully "on," with its C-band telecommunications payload still functioning even as it has left its assigned orbital slot of 133 degrees west longitude 36,000 kilometers over the equator.

Galaxy 15 stopped responding to ground controllers on April 5. The satellite's manufacturer, Orbital Sciences Corp. of Virginia, says an intense solar storm in early April may be to blame. It was launched into space in 2005.

The first satellite likely to face signal interference problems from the adrift Galaxy 15 is the AMC-11 C-band satellite owned by SES of Luxembourg and stationed at 131 degrees west, just two degrees away from Galaxy 15's starting position.

Rob Bednarek, chief executive of the SES World Skies division, which operates AMC-11, said Intelsat and SES have been meeting since April 5 to coordinate how to minimize the Galaxy 15 impact on AMC-11's media customers.

Adrift in space
In an interview Friday, Bednarek said that while it remains unclear whether SES World Skies will be able to avoid a signal interference problem as Galaxy 15 enters the AMC-11 orbital territory, the company has benefited from full disclosure on the part of Intelsat, SES's biggest competitor.

"The cooperation with them really has been very good," Bednarek said. "We all realize that we could be in the same position tomorrow. We are neighbors in space."

Alan Young, chief technology officer at SES World Skies, said the company's best estimate is that Galaxy 15 will enter AMC-11's neighborhood — meaning one-half of one degree distant — May 23. It will continue traveling at its own pace through the AMC-11 slot, exiting on the east around June 7.

Young said the period of May 31 to June 1 is going to be the riskiest time for AMC-11 customers as SES World Skies seeks to maneuver AMC-11 to the maximum extent possible out of the Galaxy 15 track while at the same time maintaining links with the company's AMC-11 customers.

Tobias Nassif, Intelsat's vice president for satellite operations and engineering, said Friday that the company, in concert with Orbital Sciences, has sent between 150,000 and 200,000 commands to the satellite in the nearly four weeks since the satellite stopped sending or responding to commands.

These communication attempts, the equivalent of mild wake-up calls to return Galaxy 15 to service, have had no effect. As it moved all Galaxy 15 customers onto Galaxy 12, which was pulled into service from another orbital location, Intelsat at first focused on recovering Galaxy 15 to regular service.

Zombie satellites in space
On Monday, Intelsat played what appeared to be its last card by blasting Galaxy 15 with a more powerful signal intended not to salvage the satellite, but to force it into a complete shutdown.

That attempt was to last about 30 minutes. It will not be repeated, both because a second attempt is viewed as unnecessary — the treatment works or it does not — and because sending out powerful radio frequency signals carries the risk of interfering with other satellites in the area.

Even if Monday's action succeeds, Galaxy 15 will remain a problem as it continues to wander the geostationary arc. But it is a problem that satellite operators know how to deal with. Industry experts say there are several dozen spacecraft, sometimes called "zombiesats," that for various reasons were not removed from the geostationary highway before failing completely.

Depending on their position at the time of failure, these satellites tend to migrate toward one of two libration points, at 105 degrees west and 75 degrees east. Figures compiled by XL Insurance of New York, an underwriter of space risks, say that more than 160 satellites are gathered at these two points, which Bednarek described as the orbital equivalent of valleys.

"Unfortunately for us, we were downhill from Galaxy 15 as it rolls toward" the 105 degrees west libration point, Bednarek said.

Satellite signal stealer
Satellites like Galaxy 15 and AMC-11 are so-called "bent-pipe" designs that receive signals from the ground, amplify them on board and redistribute them to customers' ground antennas. Emptied of its customers — except one, the U.S. Federal Aviation Administration, which uses an L-band payload on Galaxy 15 to guide aircraft landings — Galaxy 15 is no longer broadcasting. But its electronics payload is ready to capture and rebroadcast signals it receives that are intended for other spacecraft.

Young said that both SES and Intelsat are fortunate in this case because their two satellites' customers are mainly media companies using fairly large antennas to communicate with the satellites. During the period of maximum danger for AMC-11, SES expects to be able to reroute customer signals to SES-operated teleports with still-larger antennas to maintain communications links.

Nassif said Intelsat and Orbital Sciences have solicited outside opinions from other satellite manufacturers on possible maneuvers that might return Galaxy 15 to control or force it to shut down.

"The fact is that this is the first major anomaly on an Orbital-built satellite," Nassif said. "Other manufacturers have been through problems and might have something to suggest to us."

Click for related content

Oil spill hinders space shuttle fuel tank delivery
Huge space balloon crashes in Australia
Cosmic Log: See the spill from space

Because nothing like this has happened before, Intelsat remains uncertain as to when Galaxy 15, as its Earth sensor realizes it is no longer in the desired position, might lose its Earth-pointing capability. That would lead to its solar arrays losing their lock on the sun. Within hours, the satellite's batteries would discharge and the spacecraft would shut down on its own.

While cautioning that the company is revising its most-likely-scenario thinking almost on a daily basis as it gets input from Orbital Sciences and others, Nassif said the current estimate is that Galaxy 15 will lose Earth pointing by late July or early August.

As luck would have it, that timetable would mean the only other satellites in Galaxy 15's C-band frequency that face interference issues are owned by Intelsat.

After it leaves the vicinity of AMC-11, Galaxy 15 is expected to approach Intelsat's Galaxy 13 satellite, at 127 degrees west, around July 13. On July 30, it will enter into the Galaxy 14 satellite's orbital territory at 125 degrees west before heading toward Galaxy 18 at 123 degrees in mid-August.

"We are in regular contact with all our customers of these satellites to keep them apprised of the situation," Nassif said.

Cassini’s Latest Discoveries :

This view of Titan uncovers new territory not previously seen at this resolution by Cassini's cameras. Some of the territory in this view was covered by observations made by the Cassini synthetic aperture radar in October 2004 and February 2005.





Cassini Views of Titan:

These three views of Titan from the Cassini spacecraft illustrate how different the same place can look in different wavelengths of light. Cassini's cameras have numerous filters that reveal features above and beneath the shroud of Titan's atmosphere. All of these images were taken with the Cassini spacecraft wide angle camera on April 16, 2005, at distances ranging from approximately 173,000 to 168,200 kilometers (107,500 to 104,500 miles) from Titan and from a Sun-Titan-spacecraft, or phase, angle of 56 degrees.



Enceladus to Scale

Saturn's moon Enceladus is only 505 kilometers (314 miles) across, small enough to fit within the length of the United Kingdom, as illustrated here. The intriguing icy moon also could fit comfortably within the states of Arizona or Colorado.

Ringside with Dione:

Saturn's moon Dione, with the planet and rings also viewable. The images were obtained with the Cassini spacecraft wide-angle camera on October 11, 2005.


Craters, Craters Everywhere

Craters within craters cover the scarred face of Saturn's moon Rhea in this oblique, high-resolution view of terrain on the moon's western hemisphere. This is one of the highest-resolution images of Rhea's surface obtained during Cassini's close flyby on Nov. 26, 2005

Out-of-the-world discoveries - recent space discoveries of two new planets, A new mass of interstellar matter, and billions of new galaxies

Astronomers announce three stunning space discoveries. Could these findings mean we are not alone in the universe?

Astronomers say they may have found at least half of the universe's "missing mass." Since the 1930s, scientists have been looking for this invisible mass, also called "dark matter," which they say keeps galaxies from flying apart. (By their calculations, all the visible stars don't have enough mass, and therefore gravitational pull, to hold galaxies together.)

How did astronomers find this dark matter? They detected increases in the brightness of stars in a nearby galaxy. This brightening, they say, could only be caused by large objects passing in front of the stars. The objects' mass indicates that they are white dwarfs, or burned-out stars. If enough of these dead stars exist in space, they could make up half of the universe's missing mass. What about the other half? Scientists are still looking.

TWO NEW PLANETS

Those who hope to find life elsewhere in the universe have a couple of new places to look: two larger-than-Jupiter planets just discovered orbiting faraway stars. Astronomers detected variations in the light coming from each star, which could be caused by a large planet in orbit. The stars, very similar to the Sun, are about 35 light-years away. (A light-year is the distance light travels in one year, about 9.5 trillion kilometers.)

Based on the stars' brightness and their estimated distances from their planets, scientists think both planets may be warm enough for water to exist there. Since water is essential to life on Earth, the discovery prompts the question: Could these new planets harbor life? Stay tuned as scientists search for signs!

BILLIONS OF NEW

GALAXIES

New photos from the Hubble Space Telescope reveal that the universe may be a lot more crowded than scientists once thought. The photos, like this one, reveal some 1,500 galaxies (groups of stars like our Milky Way) in a tiny speck of space. Based on their view of that speck, scientists now estimate there may be 50 billion galaxies in the universe - 5 times their previous estimate. With 50 to 100 billion stars in each galaxy, the universe may contain 5,000,000,000,000,000,000,000 stars - or about one trillion stars for every person on Earth!

New Asteroid Threat to Earth???????????????

Although scientists have basically cleared us from any danger from asteroid 2002 NT7, which originally had been reported as an impact hazard for the year 2019, a newer space rock has been spotted, which may pose a threat even sooner.

At around 1.2 km in width, 2003 QQ47 is substantially smaller than 2002 NT7 (2km), but has been called "an event meriting careful monitoring" by astronomers. If an impact does occur, it could be on March 21, 2014.

Discovered on August 24, 2003, by the Lincoln Near Earth Asteroid Research Project (an MIT Lincoln Laboratory program funded by the United States Air Force and NASA) in New Mexico, 2003 QQ47 has been classified as a 1 on the Torino scale of impact hazards. Scientists are urging calm, however, saying the odds of a catastrophic collision are only around 1 in 909,000.

The orbit of this asteroid has been calculated on only 51 observations during a seven-day period and require further observations to determine if any danger does exist. It will be monitored closely over the next two months. Astronomers expect the risk of impact to decrease significantly as more data is gathered.

If it does strike Earth, the impact could have the effect of over 20 million Hiroshima style atomic bombs. As Billy Bob Thornton says in Armageddon, “It's what we call a Global Killer....the end of mankind. Half the world will be incinerated by the heat blast.....the rest will freeze to death in a nuclear winter. Basically, the worst part of the Bible!”

Asteroids are rocks and debris which are the leftovers of the construction of our solar system nearly 5 billions years ago. Most are in a belt, which orbits the sun between Mars and Jupiter. However, the gravitational influence of the gas giant planets, like Jupiter, or an impact by a comet can knock these large rocks out of their safe orbit.

Needless to say, we will be monitoring this situation very closely.

Update:

Once again, the planet can breathe a sigh of relief. After making further observations of asteroid 2003 QQ47, astronomers now say there is no threat from this rock. It has been downgraded to a zero (0) on the Torin scale, which says, "The likelihood of a collision is zero, or well below the chance that a random object of the same size will strike the Earth within the next few decades. This designation also applies to any small object that, in the event of a collision, is unlikely to reach the Earth's surface intact."