NASA’s twins that could save our world

Wikipedia Imagine a billion tonnes of scorching hot gas and radiation being hurled toward you – it’s not the sort of thing you come across every day.

This is actually something our Sun does on a regular basis, although fortunately for us our atmosphere stops anything too dangerous getting in and hurting us.

But satellites, as well as any astronauts in space, feel the full force of a Coronal Mass Ejection (CME) – as these massive bursts from the Sun are known – and they can be really dangerous.

That’s why NASA decided to launch the Stereo mission, two twin satellites that give us unprecedented views of CME’s – something that would be vital if a CME was ever to come toward us. (Click here for two interesting videos from Stereo)

And it’s not just about damage prevention – we’re learning loads about the Sun too like new footage from Stereo showing just how powerful solar bursts can be as they rip the tail off a comet. The Stereo probes are telling us loads of things we didn’t know about our parent star.

BBC NewsSo why are there two probes in Stereo – wouldn’t just one have been cheaper? The whole point of Stereo is to give us a 3D view of the Sun – just like having two eyes a small distance apart helps our brains give depth to our vision, the two Stereo probes can give us a three-dimensional view of our Sun because one follows a path slightly in front of Earth’s orbit, and its twin trails on behind.

What would happen if one of these CME’s flew straight into our planet? Something not many people realize is that the effects on our lives could actually be huge. For a start many satellites would be knocked out, meaning no television, GPS, weather forecasting and more for a few days. And then there’s cell phones, the internet, and anything else that needs satellites to work.

Wikipedia The good news is that thanks to Stereo, we will be given a few hours’ warning if a CME is heading toward our planet, giving operators vital time to shut down any satellites in the path of the Solar blast, as well as making sure any astronauts are safely inside radiation-proof areas.

The wonderful Stereo probes are yet another example of why scientific research isn’t just about proving some professor’s theory or doing some irrelevant calculations – it really could save our lives. Of course, until the day when a CME is headed our way, it’s always fascinating  to discover more about our amazing Universe.

Interested? Read about how radiation could prevent humans from ever going to Mars.


Vanguard: The 5.7 billion mile satellite that never gives up

Vanguard 1 | Image: University College London Everyone knows about Sputnik, the tiny satellite that started the Space Race back in 1957, but everyone forgets that it burnt up just 3 months after it was launched – unlike an American satellite that went up just a few months later. Vanguard 1 was only the second ever successful U.S. satellite (after Explorer 1) but it is still up in space, having clocked up an amazing 5.7 billion miles over the last 50 years.

Something I hadn’t realized about Vanguard was that it is just 6 inches long – which led to it being dubbed the ‘grapefruit satellite’ by the envious Russians. Sputnik was 23 inches long – still tiny by modern standards, but a giant compared to Vanguard.

Several previous American attempts to launch satellites had gone very wrong | Image: NASA OK, so Vanguard’s been up in space for quite a while now. But was there any point in the satellite except to annoy the Soviets? Actually, it had some pretty amazing accomplishments considering how primitive it was. It surprised scientists at the time by showing that the Earth is not actually completely round, but is instead pear-shaped. Well only a little bit, but it’s still true. It’s pretty cool that a 3-pound lump of metal could discover stuff like this.

Vanguard was also the first ever spacecraft to use solar panels, a power source that kept it going for nearly 7 years until it stopped transmitting in 1964. In fact, estimates for its lifetime range from between 200 to 2000 years, after which it will plunge into our atmosphere and burn up.

Let’s just hope it doesn’t have to come down the same way as that US military satellite a few weeks ago.

Vanguard celebrates its 50th birthday Monday March 17, 2008.

Making the Internet 20,000 times faster: New satellite launched

'Kizuna' lifts off from Japan | Image: CNN The internet’s come a long way over the past few years, increasing in speed many times since the days of 56k Dial-Up.

But imagine being able to surf the web at speeds over 20,000 times faster than dial-up – thanks to a new satellite launched by Japan, that may soon be possible. The idea is that rather than using cables to transfer data, satellites and receiving dishes could be used to connect to the internet.

It’s all very well being able to download the latest movies onto your computer 20,000 times faster, but what will the real advantages of super high-speed internet be?

For a start, it could enable remote communities to get access to healthcare because all that would be needed to access the web would be a small, portable satellite dish, rather than miles of cable. Many rural communities around the world cannot access the internet at the moment because of the huge costs, but this new satellite technology could really change lives.

Satellite internet would also enable e-learning to really take off, with teachers able to talk to their pupils in real time through very high quality video.

The new satellite (Kizuna) is only meant to be experimental, but it is the start of a revolution in internet access. It will initially only be available for use in Asia, though Japan may open it up for testing by other countries as well in the future.

US to shoot down dead spy satellite: Why?

This rocket took the satellite up in December, and now it's falling back down again | Image: CNN / U.S. Air Force It’s the size of a bus, weighs 5000 pounds and contains gallons of the highly toxic rocket fuel hydrazine. And until recently it could well have landed in your back yard in a few weeks time.

But thanks to a U.S. government decision, a dead spy satellite that was due to hit Earth sometime in the next few weeks will now be blasted to pieces by a missile, smashing it into millions of tiny pieces that should burn safely up in the atmosphere. Click here for more detailed background on the dead satellite.

However, many people, both professional analysts and freelance bloggers, say the real motive for shooting it down is to either test out new missile technology or to stop U.S. defense secrets being leaked, should it return safely to land.

A satellite (unrelated to the one going to be shot down) | Image: UC Berkeley The government has used the ‘excuse’ that it is necessary to stop the dangerous hydrazine fuel on board the satellite causing anyone any harm – this is also a very valid point, so let’s take a look at the safety risks of hydrazine:

  • If humans are exposed to hydrazine (chemical formula N2H4), they can suffer the usual irritant reactions – eye irritation, dizziness, nausea, etc.
  • However, it can also cause damage to the liver, kidneys and Central Nervous System
  • It is also corrosive, so could burn your skin away
  • Rodents exposed to hydrazine have an increased chance of developing tumors/cancer

OK, so hydrazine looks pretty toxic. But what would the chance have been of it smashing through your roof? Many estimates say there was around a 1% chance it would have landed in a populated area, and even then most of the satellite would have burned up in the atmosphere, leaving only the hydrazine and some scraps of metal to come to the ground. The hydrazine may well have stayed locked up in its container anyway.

I think shooting the satellite down is the best option, but I’d be really interested to hear your views too. Is it just a big government cover-up? What do you think? Post your comments below.

CNN has done an interesting analysis here.

UPDATE: The Space Shuttle will be under no danger from the satellite debris, as it will not be blown up until after the Shuttle returns to Earth Wednesday.

The mission will cost between $40 and $60 million (Click here for details).

Click here for an excellent interactive explainer detailing the satellite shoot-down mission, including a video animation

Satellite hurtling down to Earth

Skylab,which fell to Earth uncontrolled in 1979 | Image: BBC NewsRain, snow, maybe hail… it’s very rare for anything to come out of the sky and hit you really hard on the head. But the U.S. government now admits that there is a new and dangerous possibility: a bus-sized spy satellite that is currently hurtling back to Earth, completely uncontrolled. It is due to hit us late February/early March. (Click here for a fascinating video explainer)

The problem is that because it died before anyone had time to safely direct it back to Earth, no-one has a clue where it’s going to land. So it could technically land right in the middle of New York City.

However, dangerous as it may sound, the chances of actually being hit by satellite debris are less than one in a trillion – compare that to one in 1.4 million for getting struck by lightning, and it’s doesn’t sound so scary after all. In fact, back in 1979 the 78-ton Skylab Space Station fell uncontrolled back to Earth, and it landed safely in the Indian Ocean. Think of the Challenger Shuttle disaster – there was far more debris there.

Planet Earth | Image: CNN / Getty ImagesWhat would the risks be apart from being knocked unconscious? Well, the satellite does contain hydrazine, a rocket fuel toxic to anyone who comes into contact with it. But that’s basically it.

Should we be scared? The scaremongers may say yes, but of course the sensible answer is no. Even ignoring the 75% of our planet that is ocean, there are still 57,500,000 square miles of land it could touch down on as well. Don’t lose too much sleep over it.