Shuttle over London
Aug. 29th, 2009 05:56 amWhen the Space Shuttle launches to the International Space Station - which, other than the recent Hubble servicing mission, is the only place it goes these days - the need to match the ISS' orbit means that its launch trajectory invariably passes over southern England about 20 minutes after take-off. If launch happens to have been timed such that it is early dawn or late dusk in the UK at the time, then it's quite likely that the Shuttle, being some 150-200 km up, will be in sunlight and so brightly illuminated and clearly visible from below.
Yesterday I noticed that the latest launch had been rescheduled, after a number of technical hitches, for midnight Florida time. That's 5am UK time, so the Shuttle, if launched, would be passing over the UK at 5.20. Right now, dawn is at around 6, so there was every prospect of seeing the Shuttle - if it launched on time, and if (a bigger if!) the sky was clear. So I set my alarm for 4.45...
Up, and a quick check of the mission status page; yes, the countdown is in its final minutes so I turn on the TV and watch what must have been a very spectacular night launch for anyone in Eastern Florida. A peer out the window shows the odd star in the London glare, so I pull on some trousers and a top and wander out into the car park. Dawn is clearly near, with the eastern sky brightening fast, but the Shuttle will be coming from the west, so I look that way.
And there it is. Two brilliant stars, each around about as bright as Venus (say magnitude -4 or so if you want to be precise), one white, the other a very obvious orange. The white one is the Shuttle Orbiter, the orange one its External Tank, now empty of fuel and separated some eleven minutes ago. About twice the width of the Moon apart, so say a degree or so, they pass overhead in a matter of seconds at perhaps twice the apparent speed the ISS usually moves at, a consequence of them both being much lower (some 200km, vs the ISS at nearer 400). In about another twenty minutes the Orbiter will burn its manoeuvring engines to place itself fully in orbit, whilst the ET will fall back to burn up over the Pacific.
I've never seen a Shuttle launch in person, and given that it's due to retire in another year or so, I doubt I will. But I think this comes close to counting.
Yesterday I noticed that the latest launch had been rescheduled, after a number of technical hitches, for midnight Florida time. That's 5am UK time, so the Shuttle, if launched, would be passing over the UK at 5.20. Right now, dawn is at around 6, so there was every prospect of seeing the Shuttle - if it launched on time, and if (a bigger if!) the sky was clear. So I set my alarm for 4.45...
Up, and a quick check of the mission status page; yes, the countdown is in its final minutes so I turn on the TV and watch what must have been a very spectacular night launch for anyone in Eastern Florida. A peer out the window shows the odd star in the London glare, so I pull on some trousers and a top and wander out into the car park. Dawn is clearly near, with the eastern sky brightening fast, but the Shuttle will be coming from the west, so I look that way.
And there it is. Two brilliant stars, each around about as bright as Venus (say magnitude -4 or so if you want to be precise), one white, the other a very obvious orange. The white one is the Shuttle Orbiter, the orange one its External Tank, now empty of fuel and separated some eleven minutes ago. About twice the width of the Moon apart, so say a degree or so, they pass overhead in a matter of seconds at perhaps twice the apparent speed the ISS usually moves at, a consequence of them both being much lower (some 200km, vs the ISS at nearer 400). In about another twenty minutes the Orbiter will burn its manoeuvring engines to place itself fully in orbit, whilst the ET will fall back to burn up over the Pacific.
I've never seen a Shuttle launch in person, and given that it's due to retire in another year or so, I doubt I will. But I think this comes close to counting.