A nasty wallop

Ah, remember back in 2011 when the Chinese Tiangong-1 space station was launched from the Gobi Desert, setting off on its five-year mission to explore strange new worlds, to seek out new life and new civilisations, to boldly go where no man has gone bef… Look, they launched a big space station.

Why is this relevant to you or I? Well, now it seems that they have lost control of said space station and it’s going to plunge back to earth “sometime in 2017”. And if that seems vague, then understand this:

Not knowing when it’s going to come down translates as not knowing where it’s going to come down.

Those would be the words of Jonathan McDowell, renowned Harvard astrophysicist and space industry enthusiast. He continues:

You really can’t steer these things. Even a couple of days before it re-enters we probably won’t know better than six or seven hours, plus or minus, when it’s going to come down. A slight change in atmospheric conditions could nudge the landing site from one continent to the next.

But thankfully, between us and the stricken satellite is the atmosphere: all round lekker ding and protective blanket around our flimsy planet with its fragile residents. And we all know that things entering or re-entering the earth’s atmosphere generally burn up harmlessly.

Generally. Some bits might get through though.

Little bits. Like the super dense rocket motors:

There will be lumps of about 100kg or so, still enough to give you a nasty wallop if it hit you.

What?

Yes there’s a chance it will do damage, it might take out someone’s car, there will be a rain of a few pieces of metal, it might go through someone’s roof…

A 100kg chunk of super dense metal, falling from 450km up “might go through someone’s roof”? I’d suggest that Jonathan McDowell has been astrophysicating so long that he’s forgotten about the 9.81 m/s² force of gravity pulling things (like 100kg chunks of super dense metal) mainly downwards towards us.

Of course, you’d have to be pretty unlucky to be hit by any of this debris, but – without wanting to cause any sort of panic – I’d think that “a nasty wallop” might be a slight understatement as to the effect it might have if it was to land on you.

Hang on. What’s that strange noise? Part shriek, part holler…

Oh – it’s Wu Ping – Chinese space official, who tells us:

Tiangong-1 is currently intact and  authorities will continue to monitor it and strengthen early warning for possible collision with objects.
If necessary, China will release a forecast of its falling and report it internationally.

How very generous of them.

We’ll be keeping an eye on this story over the next 3 to 15 months (seriously – no-one has a single clue when this thing is going to crash), and keep you informed of what we learn and the location of the best caves in the expected landing area.

ISS mess

One of the best things about being a Dad is being able to tell your offspring amazing things.
Often, these things aren’t actually true and even if they are, parental licence allows for a huge degree of exaggeration.
I follow @twisst14, one of the twisst.nl bots on twitter, who helpfully tell me (to the nearest second) what time the International Space Station is coming over Cape Town. They can do it for wherever you’re based as well.
Forearmed with this information, I can confidently predict exactly when Alex is going to see a “shooting star” going across the sky.
The fact that I am always right fills him with amazement – a totally different reaction from that of his mother when I tell her that I’m always right.

Tonight’s ISS pass was very bright, but then so was the sky behind it and the long exposure on my camera was sadly affected by the blustery south-easter. Then Alex went a bit mad on Picasa and we ended up with the picture above. Bit retro and kinda funky, but not as sharp as the last time I snapped the ISS over Constantiaberg – so I’m calling it “ISS mess”.

Twisst tells me that I have another opportunity to spot the ISS again this evening at 21:02:58 and – judging by the snoring coming from Alex’s room – this time I’ll be watching it on my own.

UPDATE: Looked a lot better the following evening.