July 20th, 2010
The mission has zeroed in on a flipped or bad bit in the flight data system being the likely culprit for the spacecraft's current problem with formatting science data properly. Remember that computers store information as strings of ones and zeroes or "on" and "off" bits. Once in a while, a passing cosmic ray can evade the radiation protection on a spacecraft and slam into a memory bit; when that happens, the bit may change value, from zero to one or vice versa. It's a lot like a transcription error in DNA; it's a sort of mutation of the code. It's possible that the flipped bit will have no or insignificant effect on the spacecraft, but once in a while, a flipped bit happens in a very important location and causes serious problems, and that's what the Voyager team thinks happened within Voyager 2's flight data systems.
The view from the International Space Station as it flies through an Aurora at 28,000km/hr.
Never mind the image quality, feel the speed.
[Via Bad Astronomy]
I've seen still images of Daphnis causing a perturbation in Saturn's A Ring before, but this Cassini video of Daphnis ploughing through the rings was new to me. Seriously cool.
What self-respecting geek could resist an RSS feed notifying you every time another star falls within your light cone?
72 Herculis is 46.9 light years from Earth. It was enveloped by your light cone 2 months ago.
Nu-2 Lupi, here I come…
[Via James Nicoll]
Fortunately, it turns out that there is a good explanation for why Obama canceled the Constellation program. That explanation has been provided by Richard C. Hoagland. Hoagland, you may remember, is the person who discovered the lost city on Mars, and a bunch of giant invisible structures on the Moon that he asserts are the remains of alien civilizations. They're there, he says, but because they are invisible we have to trust him.
Hoagland has come up with a startling revelation… that Obama canceled the lunar program because (drum roll please): he was warned by Space Nazis. [...]
It's crazy, but it's not quite up there with my favourite Hoagland theory, about Iapetus. Now that's quality crazy.
[Via James Nicoll]
8. Greg in Austin Says:
February 15th, 2010 at 11:37 am
I can imagine one of the Cassini engineers here on Earth programming in the flight pattern:
Engineer: "Keep your distance, but don't look like you're keeping your distance."
Engineer: "I don't know. Fly casual!"
Secrets of The Shining: Or How Faking the Moon Landings Nearly Cost Stanley Kubrick his Marriage and his Life…
It is time to shed the lies. But also it is time for the world to view, uncensored, Stanley Kubrick's greatest unknown masterpiece. I ask NASA to release all of the footage directed by Kubrick for the faked Apollo landings.
May I also suggest that NASA use the millions of dollars made from this surely successful movie release to fund another mission to the moon?
The British version of the X-Files is no more:
The government has shut a unit which has investigated UFO sightings for more than 50 years, judging its resources better spent on more earthly threats.
"The MoD has no opinion on the existence or otherwise of extra-terrestrial life. However, in over 50 years, no UFO report has revealed any evidence of a potential threat to the United Kingdom," it said in a statement.
Sceptical readers will note that they don't say that UFOs don't exist, just that there's no threat to the UK. Is this because they've found no evidence of alien visitors to UK airspace, or <paranoia level="maximum">compelling evidence that the government has already signed a non-aggression pact with an alien power?</paranoia>
[Via Blood & Treasure]
On the way past Earth one last time, the Rosetta probe grabbed a couple of gorgeous photographs of the crescent Earth.
I can't make my mind up which I prefer: the shot of a blue-and-white planet posted by Emily Lakdawalla or the warmer, more colourful picture posted by the ESA, featuring sunlight glinting off the ocean.
The universe turns out, once again, to be stranger than we had imagined. It's been suggested that the neutron star at the heart of Cassiopeia A has a very peculiar atmosphere:
The properties of this carbon atmosphere are remarkable. It is only about four inches thick, has a density similar to diamond and a pressure more than ten times that found at the center of the Earth. As with the Earth's atmosphere, the extent of an atmosphere on a neutron star is proportional to the atmospheric temperature and inversely proportional to the surface gravity. The temperature is estimated to be almost two million degrees, much hotter than the Earth's atmosphere. However, the surface gravity on Cas A is 100 billion times stronger than on Earth, resulting in an incredibly thin atmosphere.
50 Years of Space Exploration would benefit from a decent key explaining some of the colour coding, but even without such frills it's still pretty wonderful.
Be sure to download the large version.
[Via James Nicoll]
NASA's Lunar Reconnaissance Orbiter has started taking photos of the Apollo landing sites.
At the moment LROC is orbiting at a relatively high altitude, but NASA plan to make further passes over the landing sites in September which will give us a better look at the Lunar Modules, the instrument packages and the tracks left by the Lunar Rovers. I can't wait.
I've seen plenty of film of the Space Shuttle blasting off. I've even seen footage from a camera strapped to the side of a shuttle at lift-off. Until today, I'd never seen a film showing a Solid Rocket Booster's fall back to Earth.
The images of the shuttle taking off and accelerating towards orbit are pretty routine. The latter half of the film, from the last glimpse of the Shuttle – still attached to the external fuel tank – carrying on into orbit while the booster begins the long, long fall earthwards, is one of the most awe-inspiring film sequences I've ever seen.
Purposefully crashing something into the moon just to watch what happens is akin to a schoolboy cutting up a live frog to see what makes it jump. It is an example of the domination of the left-brained rational scientific approach over the intuitive.
Did these scientists talk to the moon? Tell her what they were doing? Ask her permission? Show her respect?
[Via Ben Goldacre]
Alan Stern discusses the history of NASA's attempts to find evidence of the presence of water ice on the Moon and details the steps NASA's Lunar Reconnaissance Orbiter will be taking over the next year to resolve the issue:
What is clear about lunar polar ice is that it is hard to confirm with any single technique from orbit. And although it would be much easier to confirm with a properly equipped polar rover, such a mission would be far more expensive than LRO and is not yet on the books. NASA planners putting together the payload for LRO recognized both of these facts, and assembled an armada of five separate instruments that could search for the ice from orbit, each using an independent and complimentary technique.