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Submission + - First Details of Chinese Spacecraft's Asteroid Encounter

the_newsbeagle writes: Chinese aerospace engineers have revealed, for the first time, details about their Chang’e-2 spacecraft’s encounter with the asteroid Toutatis last month. They have plenty to boast of: The asteroid flyby wasn’t part of the original flight plan, but engineers adapted the mission and navigated the satellite through deep space.

Exactly how close Chang'e-2 came to Toutatis is still unclear. The article states that the first reports “placed the flyby range at 3.2 km, which was astonishingly—even recklessly—tight. Passing within a few kilometers of an asteroid only 2 to 3 km in diameter at a speed of 10 730 meters per second could be described as either superb shooting or a near disaster.” If the Chinese spacecraft did pass that near, it could provide a “scientific bonanza” with data about the asteroid’s mass and composition.

Comment more detail needed (Score 1) 85

I think you may be asking for the impossible. Well maybe not. I think that your question needs more details. The following information would be useful:
  • What you are mounting on the equatorial mount? Is it a telescope or a camera? How big of a telescope?
  • What are you trying to photograph

If you are trying to photograph deep sky objects through a mid sized telescope, I don't think you will find a mount in your budget range, unless you can get one used off of ebay or some such. The tabletop equatorial mount might be appropriate if you're just doing the sky. However, for a telescope, just the motors for a good equatorial drive will set you back $100 or more....

If you are only trying to photograph planets or the moon, you won't need any tracking ability to get spectacular photographs.

Comment Re:But what about the massive environmental damage (Score 1) 325

Actually, Lithium is one of the least abundant elements in the universe, at least in terms of elements that don't decay radioactively. Quoth wikipedia:

Though very light in atomic weight, lithium is less common in the solar system than 25 of the first 32 chemical elements.

The lack of lithium in the universe is one of the great unsolved mysteries in astronomy.

Comment Re:Back in the day... (Score 3, Interesting) 629

Actually, they still sell logic chips and miscellaneous electronic components, albeit fairly well-hidden in the back of the store. I had a last minute idea for a project for a summer camp group I was leading last week and was able to pick up all the components I needed from RadioShack. Admittedly, the selection isn't what it used to be, but it's still there when you have a sudden pressing need for resistors, LEDs, transistors and capacitors....

Who knows what this "rebranding" will do for that section of the store....

Comment Old news.... (Score 5, Informative) 146

This is not a new idea. Actually, this idea has been thought about before and dismissed. The researchers referenced propose using millisecond radio pulsars for navigation. This is a poor idea from an engineering standpoint because it requires having a large collecting area of radio dishes in order to get an apporpriate signal level.

A better idea, which is currently being researched, and was suggested four years ago (at least the earliest I recall it being mentioned) was using x-ray pulsars, which require much smaller collecting area. See for example this thesis on the subject.

Submission + - Satellites collide (

Geoffrey.landis writes: "We've been launching satellites for fifty years now, and for the first time, two satellites collided. Tuesday at about noon, an Iridium communications satellite and a defunct Russian satellite collided an altitude of 790 kilometers (491 miles) above northern Siberia, creating a cloud of debris. The international space station does not appear to be threatened by the debris, they said, but it's not yet clear whether it poses a risk to any other military or civilian satellites."

Submission + - Two Satellites Collide in Orbit

DrEnter writes: According to this story on Yahoo, two communications satellites collided in orbit, resulting in two large clouds of debris. The new threat from these debris clouds hasn't been fully determined yet. From the article:

The collision involved an Iridium commercial satellite, which was launched in 1997, and a Russian satellite launched in 1993 and believed to be nonfunctioning. Each satellite weighed well over 1,000 pounds.

This is the fifth spacecraft/satellite collision to occur in space, but the other four were all fairly minor by comparison.


Submission + - Comcast to face BitTorrent Filtering Lawsuits

An anonymous reader writes: It's been widely reported that Comcast is engaged in a sneaky form of Internet filtering. The company is terminating its customers' BitTorrent sessions by sending misleading data onto the network. The end result is that instead of targeting key heavy users, Comcast is instead engaged in an all out war against P2P protocols. In an interview with CNET, the Electronic Frontier Foundation's Fred von Lohmann states that Comcast is "throwing a spanner in the works of the Internet, hoping that this will somehow reduce bandwidth usage overall." Other lawyers seem to have smelled blood, and are circling in the water. Lohmann reveals that "[The EFF has] already been contacted by attorneys who are considering legal action against Comcast." Could Comcast be facing a class-action? Where do I sign up?

Submission + - Jack Valenti, Dead at 85

saforrest writes: Jack Valenti, a man whose influence in both Washington and Hollywood was profound, died today at age 85. He first became famous as special assistant to Lyndon Johnson: he can even be seen in the famous photo aboard Air Force One; he later recounted some of his experiences with the Johnson administration. In 1966, he quit this job to become what Slashdotters will undoubtedly know him best for: the staunchest promoter of copyright powers in America, as the longtime president of the MPAA, from 1966 to 2004.

Submission + - Jack Valenti has passed away

norminator writes: Jack Valenti, head of the MPAA for 38 years, passed away this afternoon in his home. Valenti is known among the Slashdot community as a man who did not believe in fair use, including backing up your digital media. From a Slashdot article four years ago: "In the digital world, we don't need back-ups, because a digital copy never wears out. It is timeless."
The Internet

Submission + - The Story behind funky, ad-laden domains

Dollaz writes: Entrepreneurs have been taking advantage of a five-day grace period to sample millions of domain names, keeping the relative few that might generate advertising revenues and dropping the rest before paying. It's akin to buying new clothes on a charge card only to return them for a full refund after wearing them to a big party.

The grace period was originally designed to rectify legitimate mistakes, such as registrants mistyping the domain name they are about to buy. But with computer automation and a burgeoning online advertising market, entrepreneurs have turned the return policy into a loophole for generating big bucks. trepreneurs-sampling.htm

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