Baby Jupiters Must Gain Weight Fast

The planet Jupiter gained weight in a hurry during its infancy. It had to, since the material from which it formed probably disappeared in just a few million years, according to a new study of planet formation around young stars.

  Smithsonian astronomers examined the 5 million-year-old star cluster NGC 2362 with NASA's Spitzer Space Telescope, which can detect the signatures of actively forming planets in infrared light. They found that all stars with the mass of the Sun or greater have lost their protoplanetary (planet-forming) disks. Only a few stars less massive than the Sun retain their protoplanetary disks. These disks provide the raw material for forming gas giants like Jupiter. Therefore, gas giants have to form in less than 5 million years or they probably won't form at all.

"Even though astronomers have detected hundreds of Jupiter-mass planets around other stars, our results suggest that such planets must form extremely fast. Whatever process is responsible for forming Jupiters has to be incredibly efficient," said lead researcher Thayne Currie of the Harvard-Smithsonian Center for Astrophysics. Currie presented the team's findings at a meeting of the American Astronomical Society in Long Beach, Calif.

Even though nearly all gas giant-forming disks in NGC 2362 have disappeared, several stars in the cluster have "debris disks," which indicates that smaller rocky or icy bodies such as Earth, Mars, or Pluto may still be forming.

"The Earth got going sooner, but Jupiter finished first, thanks to a big growth spurt," explained co-author Scott Kenyon.

Kenyon added that while Earth took about 20 to 30 million years to reach its final mass, Jupiter was fully grown in only 2 to 3 million years.

Previous studies indicated that protoplanetary disks disappear within 10 million years. The new findings put even tighter constraints on the time available to create gas giant planets around stars of various masses.

Possible Abnormality In Fundamental Building Block Of Einstein's Theory Of Relativity

Physicists at Indiana University have developed a promising new way to identify a possible abnormality in a fundamental building block of Einstein's theory of relativity known as "Lorentz invariance." If confirmed, the abnormality would disprove the basic tenet that the laws of physics remain the same for any two objects traveling at a constant speed or rotated relative to one another.

     IU distinguished physics professor Alan Kostelecky and graduate student Jay Tasson take on the long-held notion of the exact symmetry promulgated in Einstein's 1905 theory and show in a paper to be published in Physical Review Letters that there may be unexpected violations of Lorentz invariance that can be detected in specialized experiments.

"It is surprising and delightful that comparatively large relativity violations could still be awaiting discovery despite a century of precision testing," said Kostelecky. "Discovering them would be like finding a camel in a haystack instead of a needle."

If the findings help reveal the first evidence of Lorentz violations, it would prove relativity is not exact. Space-time would not look the same in all directions and there would be measurable relativity violations, however minuscule.

The violations can be understood as preferred directions in empty space-time caused by a mesh-like vacuum of background fields. These would be separate from the entirety of known particles and forces, which are explained by a theory called the Standard Model that includes Einstein's theory of relativity.

The background fields are predicted by a generalization of this theory called the Standard Model Extension, developed by Kostelecky to describe all hypothetical relativity violations.

Hard to detect, each background field offers its own universal standard for determining whether or not an object is moving, or in which direction it is going. If a field interacts with certain particles, then the behavior of those particles changes and can reveal the relativity violations caused by the field. Gravity distorts the fields, and this produces particle behaviors that can reveal otherwise hidden violations.

The new violations change the gravitational properties of objects depending on their motion and composition. Objects on the Earth are always moving differently in different seasons because the Earth revolves around the Sun, so apples could fall faster in some seasons than others. Also, different objects like apples and oranges may fall differently.

"No dedicated experiment has yet sought a seasonal variation of the rate of an object's fall in the Earth's gravity," said Kostelecky. "Since Newton's time over 300 years ago, apples have been assumed to fall at the same rate in the summer and the winter."

Spotting these minute variances is another matter as the differences in rate of fall would be tiny because gravity is a weak force. The new paper catalogues possible experiments that could detect the effects. Among them are ones studying gravitational properties of matter on the Earth and in space.

The Standard Model Extension predicts that a particle and an antiparticle would interact differently with the background fields, which means matter and antimatter would feel gravity differently. So, an apple and an anti-apple could fall at different rates, too.

"The gravitational properties of antimatter remain largely unexplored," said Kostelecky. "If an apple and an anti-apple were dropped simultaneously from the leaning Tower of Pisa, nobody knows whether they would hit the ground at the same or different times."

Ford unveils automated parking system for Lincoln MKS and MKT

Ford is introducing an automatic parking system in the flagship Lincoln MKS sedan, as well as the upcoming Lincoln MKT seven-seat luxury crossover, to help drivers parallel park with ease. Known as 'Active Park Assist', the system will be available in mid-2009 as an option on both cars. Earlier this year, we reported that Ford was planning on fitting around 90% of its vehicles with electronic steering, and that this electronic steering technology would facilitate the implementation of an automatic parking system, similar to that seen in luxury marques such as Lexus. However, unlike camera-based systems used in Lexus models, 'Active Park Assist' uses an ultrasonic-based sensing system and Electric Power Assisted Steering (EPAS) to position the vehicle for parallel parking, calculate the optimal steering angle and steer the vehicle into a parking spot. According to Ford, the technology is a "major leap forward in speed and ease of use compared with the camera-reliant systems offered by competitors" as the system requires less driver interface and reduces the risk of selecting a parking spot that is too tight, as well as having the ability to work in downhill parking situations. Practically speaking, using the system itself is fairly simple - the driver activates the system by simply pressing an instrument panel button, which activates the ultrasonic sensors to measure and identify a feasible parallel parking space. The system then prompts the driver to accept the system assistance to park, at which point the steering system then takes over and steers the car into the parking space hands-free. Like other systems, the driver still shifts the transmission and operates the gas and brake pedals while a visual and/or audible driver interface advises the driver about the proximity of other cars, objects and people and provides instructions until the park is complete. In the event of anything untoward, the driver can interrupt the system by grasping the steering wheel and using the brakes. Currently, Ford plans to fit even more models with electronic steering, which means that more and more Ford models should be available with the Active Park Assist feature in the near future. On top of helping drivers park their vehicles, electronic steering improves fuel economy up to 5 percent, while reducing CO2 emissions and enhancing steering performance compared with traditional hydraulic powered-assisted steering systems.

Lincon MKS

 

Lincon  MKT

NASA says Columbia crew had no chance to survive

Astronauts on theshuttle Columbia were trying to regain control of their craft before it broke apart in 2003, but there was no chance of surviving the accident, a NASAreport said on Tuesday.

     From the crew's perspective, the shift from what appeared to be a normal descent on February 1, 2003, into disaster happened so fast that the astronauts didn't even have time to close the visors on their helmets.

Columbia broke apart about 12 miles over Texas as it headed for landing at the Kennedy Space Center. The cause of the accident was traced to a hole in one of the shuttle's wings, which was hit by a piece of falling foam insulation during launch 16 days earlier.

Seven astronauts, includingIsrael's first astronaut Ilan Ramon, were killed when superheated atmospheric gases blasted inside the breach like a blow torch, melting the ship's structure.

The crew cabin broke away from the ship and started spinning rapidly. Analysis of the wreckage indicated the crew members had flipped cockpit switches in response to alarms that were sounding. The astronauts had also reset the shuttle's autopilot system, the report said.

"We have evidence from some of the switch positions that the crew was trying very hard to regain control. We're talking about a very brief time in a crisis situation," said NASA's deputy associate administrator, Wayne Hale.

But rapid depressurization caused the Columbia crew to lose consciousness, and medical findings show that they could not have recovered, said the report, which took four years to compile.

"This report confirms that although the valiant Columbia crew tried every possible way to maintain control of their vehicle, the accident was not ultimately survivable," said Hale, who oversaw the shuttle program during its return to flight after the accident.

TRAUMATIC INJURIES

Analysis shows the astronauts' shoulder harnesses failed and their helmets did not adequately protect their heads. The lack of safety restraints caused traumatic injuries.

The investigation also found problems with the shuttle's seats and parachute landing system, which requires astronauts be conscious to operate manually.

Even if the safety gear had worked, the astronauts would have died due to the winds, shock waves and other extreme conditions in the upper atmosphere.

Designing spacesuits that are more automated and integrated into future spaceships is among 30 recommendations made in the report.

"I call on spacecraft designers from all the other nations of the world, as well as the commercial and personal spacecraft designers here at home to read this report and apply these hard lessons which have been paid for so dearly," Hale said.

Also killed in the accident were shuttle commander Rick Husband, pilot William McCool and astronauts Michael Anderson, David Brown, Kalpana Chawla and Laurel Clark.

Much of what is in the report was discovered by the Columbia accident investigation team, which released a series of findings and recommendations six months after the disaster.

The panel advised retiring the space shuttles as soon as NASA finishes using them to complete construction of the International Space Station, a $100 billion project of 16 partner countries that has been under way for more than a decade. The shuttle Challenger broke apart in 1986.

Since the accident, NASA has flown 11 shuttle missions and has nine left in its schedule. A 10th mission to fly a physics experiment to the space station is under consideration.

Smoothbook Slice MSI Wind Netbooks

Smooth Creations Launched Msi Wind Netbooks which are a Smoothbook Slice netbook, which is in fact a rebadged netbook.The Smoothbook Slice has a case with custom, automotive-grade painting,instead of white or black cases.

The Smoothbook Slice is equipped with an Intel Atom N270 1.6GHz processor, 1GB of RAM, 120GB hard drive and a 10-inch 1024×768 LCD display.The netbook comes with pre installed windows XP Home. It is priced at $499.99, which is more expensive than the original Wind.