This is how the alien fleet begins it's attack, swallowing up most of our communications satellites, and embedding their own signal in the remainder. YOU HAVE BEEN WARNED !

Personally, I welcome our new satellite-munching overlords.

Judging from how widespread the debris from the Chinese sat-killer missile spread around the earth (http://orbitingfrog.com/blog/files/Fengyun1CDebris.kmz) having another cloud blanket us is worrysome.

Can't be long before the chain reactions start.

"here's one: the Russians deliberately rammed the Iridium sat to prevent a particular satphone call/tracker-bug message/submarine data upload getting through"

Well you don't think Putin will let himself get caught commissioning another ABBA concert do you ?

This is part of the New World Order's clandestine attempt to create a Dyson sphere surrounding the Earth, one satellite at a time. A select few will be given new homes on the inside surface of this sphere, from where they can transmit orders to the hoi polloi down below, looking up at them.

Invasion!

I like conspiracy theories... alas I have only a question, but give me time and I'm sure I could work it up

Since the US continuously tracks all satellites (and lots of debris) surely a collision would have been predicted before it happened and e.g. Iridium warned to take avoiding action - unless one satellite manoeuvred suddenly...

So - whodunnit? Was it -

a) a US anti-sat operation using an Iridium satellite (possibly specially hacked and redirected, possibly with connivance of Iridium.... ah! Got to a conspiracy at last!)

b) a Russian anti-sat operation... etc. etc.

c) a CHINESE anti-sat AND hacking operation

d) a 4Chan stunt

e) clumsy Reptilians

.....i) Arriving in time to pick up the pieces of the (crisis of your choice),

.....ii) Departing in time to avoid the (crisis of your choice)

f) a Banker

g) THEM

Oh look! The sky IS falling.

"Just for starters, here's one: the Russians deliberately rammed the Iridium sat to prevent a particular satphone call/tracker-bug message/submarine data upload getting through"

Wow, now that is what I would call Heavy MetAIdData. If we didn't know any better, you could nearly spin it as one of those Rock Chipsets Frying the Opposition and Testing IT Ranges for Roaming Renegades

the same Alien (sorry UFO ;-) ) that smashed into that Wind turbine this ET is a clumsy bastard is he not! Dread to think how high this guys galatic insurance premiums will go, just hope it doesnt cost the eath.......

>> "We believe it's the first time that two satellites have collided in orbit," the colonel added.

you "believe" (read: not sure/can't say) that is the first time two freaking satellites have collided in the freaking orbit? this is odd, no matter how you look at it, this is really odd!

@ Julian I-Do-Stuff, nice conspiracy

mine is the one made of tin foil

I find it amazing that this has happened - space is pretty big, yeah? And in comparison, satellites are quite small.

Yes, I know that they generally fly at a similar altitude (though not necessarily identical) and can often broadly follow similar paths, but we're still talking about a truly MAHOOSIVE area they can fly around in, especially given that a satellite in comparison is so diddy.

For it to happen by chance, it'd be like lobbing peanuts at eachother from opposite sides of a football pitch, and expecting them to collide in mid-air.

My foul-play tentacles are raised.

You're clearly all wrong. This was an intentional act brought about to generate public support for Star Wars Laser V2.0!

Watch out for 'scientists invent way to clear space debris' headlines on your favourite IT news site in the near future.

I hope this hasn't put any of you folks off satellites. Statistically speaking, its still the safest way to communicate.

It's just John Connor popping back from the future to ensure that Skynet never becomes sentient.

>> "We believe it's the first time that two satellites have collided in orbit," the colonel added.

>you "believe" (read: not sure/can't say) that is the first time two freaking satellites have collided in the freaking orbit? this is odd, no matter how you look at it, this is really odd!

Odd? WTF are you talking about? Why should there be anything odd about him not knowing for 100% certain whether there might or might not have been a collision between satellites sometime in the past? Do you suppose if two russian or chinese military satellites had collided in orbit they'd have bothered to inform the colonel?

The attempt to make some kind of evidence of conspiracy out of this utterly trivial workaday disclaimer is pretty desparate, really.

... that will lose its No Claims Bonus ???

And which company has a long enough ladder to do panel beating up there?

It's in space, and is weightless, therefore has no inertia. So how can two weightless objects colliding in space blow each other to smithereens? Sure, I guess they could damage each other - knock a booster out of alignment, tear a solar strip, but, surely, if they hit each other, they'll just, er, stop?

I apologise in advance if I'm being thick. No, really I do.

Mine's the one with Newton's Law for Dummies in the pocket.

Apart from shortwave, it's the only way to maintain comms with ships out in the oceans, polar stations and any other places with no cellphone infrastructure (or where you don't want to use the cellphone infrastructure).

So yes, the US military would be keen to maintain it for all those reasons, but so I imagine are the shipping companies. (Both the cruise-liner companies and the freight companies).

Also, it's useful for achieving any sort of comms with spacetime-warping islands. As long as you can cope with the revenge of the smoke monster, the occasional polar bear and a horde of 1960's hippies with machine guns....

The Iridium satellite was used to prevent the Russian satellite from destroying another one of your windmill turbines in Lincolnshire...

Yes, they are weight-less, but they are not mass-less...

Inertia is based on mass, not weight (ie KG not N) - Newtons second law (F=ma) gives you the forces involved when two objects with great mass (m) collide (diminishing velocity a=(v-u)/t=dv/dt)... I think you'll find that that's enough force to destroy a couple of flimsy splattelites!

So yes, two objects colliding in space will do lots of damage to each other. How else would the Chinese have managed to destroy a satellite with a missile? According to your prior logic, they would have just stopped each other, had a cup of tea and carried on with their existences.

Maybe if they were very solid objects, however instead they're quite fragile. LEO orbits are in the region of 8km/s, and these satellites are quite massy.

Get two meringue nests and smack them together really hard (clap your hands together while holding one in each). Now how many pieces do you have?

>> "It's in space, and is weightless, therefore has no inertia. So how can two weightless objects colliding in space blow each other to smithereens [...] surely, if they hit each other, they'll just, er, stop?"

Weightless maybe. Mass-less? No. The two satellites still have mass, therefore inertia, therefore biiiiig crash.

@ iain newby I am sure your onto something. Presumably the impending impact was identified some time ago and the Iridium sacrificed to save the US black ops beweaponed death unit parked next to it.

So what we need is a satellite with two-hundred foot arms to spread the World's largest piece of (re-inforced) flypaper. That can fly co-orbit and mop it all up in no time. Then we just aim the remains at the Sun, give it a boost and problem gone.

/is it liquid lunchtime already? I'll just get my coat....

> It's in space, and is weightless, therefore has no inertia.

You are totally wrong. It seems weightless because its in orbit & falling freely, but it has all of the mass and inertia it had on the ground. Remember that weight is not equal to mass.

"Have you had an accident or fall at work that wasn't your fault ? "

Then sue the b*******

This is what the owners if the iridium sat could do.

actually thinking about it, I never thought 'cloud' computing involved satellites !

Its all in the cloud (sorry couldn't resist)

Weight is our interpretation of the gravitational attraction of masses towards the earth. Weight varies with distance from the planet, but mass is invariant (in Newtonian mechanics). Inertia is a property associated with mass, so the inertia, i.e. the tendency to continue in a straight line without change of velocity, is identical for a satellite in orbit and its twin at rest on the ground. Momentum is mass times velocity, and is a measure of energy, again independent of gravitational attractions.

The weightlessthing is a myth.. Evertything, conceptually, is simply falling at the same speed. (Don't forget that gravity is inverse-square related to distance from the mass * the mass). Weight is a function of Mass and relative gravity, the Mass remains constant even if lofted into space. It wouldn't take much to do serious damage to two solid bits of metal + hydrazine + secret russian military lasers.

This fun link might help explain it.

http://www.exploratorium.edu/ronh/weight/

@conspiracy theorists: Maybe the Iridium satellite was doing the ramming?? Maybe the US DOD is interested in the satellites as Ramming weapons, not some space age laser thingummies.

"It's in space, and is weightless, therefore has no inertia. So how can two weightless objects colliding in space blow each other to smithereens? .....I apologise in advance if I'm being thick. No, really I do...."

There are NO stupid questions..Only stupid answers.

My answer is that the satellites indeed have no 'weight', but that does not mean they have no mass. We only see weight and mass as identical because we all live in the same gravity well, but they are actually different.

Kinetic energy and inertia are dependent on mass, not weight. So each satellite will hit with 1/2 MV squared energy - which may be quite large....

With the Iridium company having a bit of a cheqeured financial history and with spare Iridium satellites up there to replace the destroyed craft my spider sense suggests this could be an insurance job. The Iridium satellites are moveable and very expensive so you would think that the company would monitor anything in it's path, after all the satellite positions are known and predictable (www.heavens-above.com has most of them on file). Quick easy way to make millions if you ask me.

Hi there, TIM SPENCE, I am guessing you are the one that I knew from school all those years back! Like the Peanut example.

There is loads of software out there for tracking satellites. I know that a Ham Radio program that I have on my Ubuntu box can track the iridium sats. Surely if Sats are in any obrit there paths can be predicted and alerts can be sent out, its a bit like air traffic control really.

@Mark Wills

"It's in space, and is weightless " does not mean mass = 0. And you will find mass matters not the weight.