Space
Meteorite strike in Norway
Here's a story that I probably would have missed if it hadn't been reported by those alert guys at Samizdata. It seems on Wednesday morning there was a big meteorite impact in Northern Norway. You can read the full story at http://www.aftenposten.no/english/local/article1346411.ece According to Aftenposten, the impact was roughly equivalent in force to the atom bomb that was dropped on Hiroshima (about 12 kilotons, if I remember right). Fortunately this happened in a very isolated area and no-one seems to have been killed or injured, which is probably why it's received almost no news coverage. Being a fairly intelligent type, I can easily imagine what the effect would have been if the meteorite had fallen somewhere more densely populated - like the center of Manchester, for instance. That would have been a real disaster, with tens of thousands of people killed and massive disruption to the surrounding area. Fortunately events like that aren't too frequent, but they do happen. The meteorite that fell in Norway was probably only a few feet or yards across. The dinosaurs are thought to have been wiped out by an impact from an asteroid several miles across. If something like that happened today there's nothing anyone could do about it. The technology to track asteroids, intercept them and move them into safe orbits does exist but it requires forward planning and a proper space infrastructure. It's one of many reasons why humanity needs to spread out into space and colonise the Solar System. The Space Age is only just beginning.
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New Horizons
It's been a good few weeks for space travel. First we've had the launch of GIOVE-A, the prototype for Galileo (Europe's independent satellite navigation system), then we've had the return of Stardust and this evening has seen the launch of New Horizons, NASA's Pluto probe - despite the launch being delayed for two days, first by high winds at Cape Canaveral, and then by a power outage at one of the tracking stations (again, caused by the weather). It's ironic that New Horizons, which is likely to spend the next few million years plunging through interstellar space, had its launch delayed by the problems of punching through those first few miles of atmosphere that surround our planet.
New Horizons was originally supposed to have launched on Tuesday evening, and I made a point of making sure I got home on time to watch on NASA TV (by way of Space.com, one of the best space websites that I know of). I wasn't going to miss a piece of history - the first Pluto probe - if I could help it. It seemed everything was OK with the spacecraft and the heavily upgraded Atlas booster that was to launch it, but I could tell from the picture that the wind was unusually strong. NASA held the countdown as long as they could while they waited for the wind speed to drop to a level where they would consider it safe to launch, but finally they got to the end of Tuesday's launch window and that was it - launch scrubbed. Not a complete surprise, of course, these kind of problems are pretty common in the space business - there's no point taking chances with all that expensive gear. Yesterday the launch was scrubbed again, due to the aforementioned power outage. Today was the third time lucky. New Horizons lifted off dead on 7.00pm GMT. NASA TV's a good way of watching a space launch if you can't be there in person. The cameras followed the spacecraft from launch, through the seperation of the five solid rocket boosters and the jetison of the payload fairing at something above 30 miles altitude. When the cameras couldn't follow the launch anymore, computer graphics were provided to show what was happening. Within three quarters of an hour of launch, the boosters, Atlas core stage, Centaur stage and upper stage had all been used up and the spacecraft was on its final trajectory, travelling so fast that it'll pass the orbit of the Moon in nine hours from launch (according to the narration). Next year it'll fly past Jupiter to pick up a gravity assist (and test the probe's instruments) and in nine years it'll reach Pluto, where it will turn its instuments on Pluto, Charon and the other satellites that have recently been discovered, before heading out through the Kuiper Belt into interstellar space. Of course a lot can happen in nine years - maybe some catastrophic failure will render the probe useless by the time it flies by Pluto - but it's on its way now, and if it works it'll be a real achievement, comparable to the Voyager and Cassine/Huygens missions.
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Stardust
Some good news on the space front today. The re-entry capsule from NASA's Stardust probe has made a successful return to Earth, carrying samples of dust from Comet Wild 2 and - hopefully - also some particles of interstellar dust. This is the first successful recovery of extraterrestrial material by a space probe since the Soviet Luna 24 mission nearly thirty years ago. It's also the first spacecraft to return samples from outside the Earth-Moon system. And it was the fastest vehicle ever to re-enter the Earth's atmosphere, coming in at 29,000mph. All in all, an impressive achievement. As a libertarian, I don't believe government-funded organisations should be exploring space, it's something that should be left to the private and voluntary sectors, but being the generation I am (I watched the Apollo landings live when I was a kid) I have to admit to having a soft spot for NASA. At least they carry out more interesting activities than other government job-creation programmes.
There's also a way that ordinary people can directly involve themselves with this mission. Now that they've recovered this material, they'll want to examine it. This shouldn't be a problem with the comet dust, but the interstellar dust that they've collected is so rarified and microscopic that they're not expecting to recover more than a few dozen tiny particles from the aerogel dust collector that the probe carried. This means that the first problem is to locate each particle. To do this, they're going to use a microscope to take millions of pictures of the collector, which someone - actually a whole bunch of someones - will have to examine frame by frame to look for signs of particle impacts. This is too much work to do in-house, so they've developed a scheme - known as Stardust@Home - to recruit loads of volunteers to download and examine the pictures on their home PCs. I quite like this idea, it's a way for people who don't have any scientific or engineering qualifications to make a non-financial contribution to an actual space exploration programme in their spare time. There's more information on this at the website here. At the moment, they're just taking the email addresses of anyone who's interested in participating. Later they'll ask volunteers to go through a test to see if they are reliable observers, then the actual programme is expected to begin in March.
The dust collector.
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Watching a Space Shuttle Launch - From the Shuttle's Point of View!
I once watched a Space Shuttle launch from ground level - while standing at the end of a short pier in Titusville, across the river from Kennedy Space Centre, to be precise. It was an experience so impressive that it'll probably stay with me till the day I die, assuming my brain's still working reasonably well by then. It's much more exciting than watching it on TV, I'd recommend it to anyone if you get the chance. Of course what I'd really like to do is watch a launch from inside the cockpit, but I'll never get a chance to do that. I have just found what may be the next best thing.
Doing a search on the internet, I found this page, on NASA's website. It seems last year's STS-114 flight was covered with video cameras, attached to every component of the Space Shuttle system, namely the Orbiter, External Tank (ET) and Solid Rocket Boosters (SRBs). I get the impression this was so they could monitor for damage and get a better idea of the stresses that a Space Shuttle is subjected to during its flight. They've put the resulting footage on their website for people to download and play. I haven't had time to look through all the video clips yet, but one that has impressed me is the top one on the page, which was taken from a camera mounted on the left SRB. It actually shows the whole flight of the SRB, from launch to splashdown. At first, you could almost think nothing's happening, as the SRB is bolted to the ET. The light gradually changes, and then the SRB seperates from the ET in the upper atmosphere. You see the other SRB using up the remainder of its fuel and then falling to Earth through the black sky, the view of Earth from 40km up, the buffetting that the SRB is subjected to when air resistance begins to take hold, the opening of the parachutes, then splashdown in the Atlantic. Absolutely brilliant, well worth having a look at.
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Cosmos 1: A private sector spacecraft.
Tonight, at approximately 20.46 BST (a few minutes from the time I'm typing this), will hopefully see the successful launch of Cosmos 1, the first lightsail to be placed in orbit. For those who aren't steeped in space technology, a lightsail is a novel type of spaceship that uses no rockets to accelerate. Instead, a thin, lightweight, reflective sail is deployed which is pushed along by the pressure of sunlight. That's right, light exerts a minute amount of pressure - you wouldn't notice it on Earth, because it's swamped by other forces such as gravity and air pressure, but it's there. What makes it practical in space is that once you get away from the Earth, air pressure ceases to be a factor and sunlight is constant, which means the pressure from those photons hitting the lightsail is causing it to accelerate by a tiny amount every second of every day. The change in velocity would be unnoticeable at first, but over days, weeks and months a lightsail should be able to accelerate to speeds beyond what could be achieved by a chemical rocket carrying the equivalent weight in fuel. Once the technology is mature, it could be a serious contender for the role of delivering space probes to other planets. Maybe later on lightsails will be used to deliver supplies to support manned exploration and colonisation of the planets - who can say at this point?
First the concept has to be proved, which is what the Cosmos 1 mission is about. The spaceship will be launched from a modified missile fired from a Russian submarine in the Barents Sea. The class of missile being used can't usually achieve orbit, but in this case a kick motor has been added to boost the 100kg spacecraft into a 800km orbit. Later, the eight triangular sails will be deployed. Each of these sails is 15m long and is made of Mylar, with a total surface area of 600m, and can each be individually adjusted to manouvre the craft. The mission planners hope to use the sails to boost the craft's orbit by 31 to 62 miles over the length of the 30-day mission. That doesn't sound a lot, but this is an experimental spacecraft, and in any case lightsails can't be expected to work as efficiently this close to Earth, due to air drag and the effect of the Sun's light being blocked periodically by the Earth. If successful, this will at least prove the concept and hopefully pave the way to future missions into deep space. After the main mission is finished, there's also some hope of testing the idea of giving the lightsail an added boost by firing microwaves at it from the Goldstone radio telescope.
What I find particularly interesting about this mission (apart from the fact that using missiles for something other than blowing people up appeals to me) is that it isn't being sponsored by any government agency. Instead, it's being run by a private group of space enthusiasts called the Planetary Society, with the actual money being put up by a TV studio called Cosmos, as well as donations from members. The total cost of the project is $4,000,000, all of it raised voluntarily from people who were interested in the project without a single penny being extorted from taxpayers. This is how space research should be done, and hopefully it's the way more of it will be done in the future. If the mission is successful, the people behind it deserve a big round of applause. If not, it's only their own money that's been wasted, and they still deserve credit for trying.
That took longer to type than I expected (I got a phone call from a friend). It's well past the nominal launch time now, I'd better post this and go and check to see if it was successful.
UPDATE 11.00pm
According to Space.com, Cosmos 1 has been successfully launched. Whether or not it achieved orbit hasn't been confirmed yet. Telemetry from the spacecraft has yet to be detected, which isn't necessarily bad news, because apparently tracking facilities in the area are a bit sketchy. Analysis of radar contacts does suggest that the kick motor fired and hopefully got Cosmos 1 into orbit, but nothing's definite yet. Let's hope there's good news tomorrow.
UPDATE 23/6/05
According to the Russians there was a failure of the booster rocket's first stage shortly after takeoff, meaning Cosmos 1 probably didn't reach orbit. Shazbot! The Planetary Society haven't completely given up hope, as they say several ground stations have received what may have been faint signals from the spacecraft, but it's not looking hopeful. Even if it did achieve orbit, it's almost certainly completely the wrong one, and a lot lower than it should be. If Cosmos 1 is in some kind of orbit, it's just possible that the sails will automatically deploy in a couple more days, obviously making it much easier to spot, but that's a long shot. This mission's almost certainly lost. I hope the launch was insured. I'd like to see the Planetary Society (or anyone else) give it another go in the near future, with a more reliable launch vehicle, if they can raise the money. The basic concept of a lightsail makes a lot of sense, it's just a matter of proving that you can manouvre one in space. This wasn't a failure of the lightsail itself, just the missile that launched it. The Planetary Society deserve credit for trying something that even NASA have never done.
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Touchdown on Titan!
In a historic first, the ESA space probe "Huygens" made a succesful landing on the surface of Titan today. Titan's dense methane atmosphere has prevented scientists from learning much about the surface in the past, although there has been speculation that there could be lakes, or even seas, of liquid methane (the temperature on the satellite being in the range where methane can exist as a solid, a liquid or a gas).
Now we finally know something about the surface. The probe started taking pictures during its descent, and this one shows the surface from about ten miles up:
You could almost be looking at a picture of Earth, with what looks like river channels and a coastline. Of course, if that's what they are, it'll be rivers of methane, not water, feeding into a methane lake - bizarre!
When the probe landed it took pictures from the surface, including this one:
It reminds me a bit of those pictures of Venus that the Soviet Venera probes took in the 70s. I understand the probe has stopped transmitting now, but that was expected - I think it only had a limitted power supply, and solar cells obviously aren't going to be any good in an environment like that. It's certainly sent enough data back to keep the scientists busy for a good while.
It's an impressive achievement. It's a shame the probe was taxpayer-funded, as I believe this kind of thing should be handled by the private sector, but all the same it's been a good day for space exploration.
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The X-Prize - we have a winner!
Well they've done it. Today SpaceShipOne, piloted by Brian Binnie, made its third flight into space, and its second X-Prize qualifying flight, following on from the flight last Wednesday, and after only five days. It reached an apogee of 114 km (77 miles), even higher than the famous X15. Coincidentally (or not) this is the 47th anniversary of the launch of Sputnik. Peter Diamandis, President of the X-Prize Foundation, issued the following statement:
“We are proud to announce that SpaceShipOne has made two flights to 100km and has won the Ansari X Prize... What we finally have here, after 40 years of waiting, is the beginning of the personal spaceflight revolution.”
Too right. Finally, manned space flight is no longer a government monopoly. From now on, anyone with the cash is going to have a chance to go, not just scientists and engineers. Already, Richard Branson has signed a deal to license the technology used in SpaceShipOne to build a fleet of commercial spaceliners, carrying five or six passengers at a time. The ticket price will be steep for the first few years - the wrong side of a hundred grand - but there was a time when air travel was only for the rich, now you can buy a plane ticket to a lot of destinations on the Continent for about the same price as a bus ticket from Manchester to London. That's the benefit of a free market. Once the price falls to something I can afford, I'd willingly pay a few grand to see views like this:
not to mention experiencing waitless conditions. This is going to be the big tourist growth industry of the next couple of decades. Time to get saving!
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