Spectacular Satellite Re-Entry Caught on Vid

[seeder]

quote:

On Thursday night, reports of a stream of UFOs over Chile and Argentina started making the rounds. It was caught on video, and it’s pretty amazing!

It’s with some relief I can say that’s not a fleet of alien spaceships bent on either enslaving the human race or possibly eating us. It's not even a swarm of meteors: what you're actually seeing there is a satellite dramatically breaking up as it re-enters the Earth’s atmosphere. And it’s even been identified: it was the Cygnus mass simulator, a payload lofted into space by the Antares rocket in April!

read more

http://www.slate.com/blogs/bad_astronomy/2013/05/11/video_satellite_re_entry_looks_like_ufos_over_south_america.html

[freetoroam]

As more private companies get into the launch game—and with everyone walking around with a private movie studio packed into their phones—we’ll be seeing more video like this. I hope that as these sightings and videos become more common, people will learn even more about what’s going on literally right over their heads.

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Are there no warnings for people when they know this is going to happen? cos they do know.

Where do the bits drop to or do they all just burn up?

[Ashotep]

I think most of them burn up but I think there should be a warning because you never know when one won't.

[Waspie_Dwarf]

Are there no warnings for people when they know this is going to happen?

Even if it was possible to know exactly where and when this was going to happen (and I will come to that in a moment) exactly what should they be warning people about? What purpose would a "totally harmless bright light in the sky" warning actually serve?

Where do the bits drop to or do they all just burn up?

Given that with this question you have shown that you do not know anything about the subject do you really think that giving a definitive statement on the subject such as the following was wise?

cos they do know.

The problem with giving definitive statements on subjects you know nothing about is that they have a very good chance of being wrong. Guess what... you are wrong.

When there are controlled re-entries, such as a Soyuz capsule or a SpaceX Dragon, or the shuttle, or even a missile warhead, then the vehicle is re-entered over a precise, predetermined location so that the vehicle (or warhead) can land at the correct location. Since the vehicle is active it can manoeuvre and so constantly correct it's trajectory.

Then we have the deliberate, preplanned re-entries of retired satellites or spent booster stages, for example the Progress (and other) freighters that visit the ISS, the Mir space station or a spent shuttle fuel tank. These will be commanded to re-enter over the ocean so that any debris will not impact over land. Although not usually under control during re-entry they will be under a controlled trajectory until they hit the atmosphere and so the point of impact of any fragments can be pre-determined.

Finally we have the uncontrolled re-entries of space debris, such as was observed here. These are dead satellites or spent rocket stages which are not under control and have orbits which have decayed naturally.

This material is tracked and organisations such as NORAD will have a rough idea of when it will re-enter. The problem is that there are many variables involved in knowing exactly when such an uncontrolled re-entry will occur. The object may vent gas which could raise or lower it's orbit. The very sparse upper atmosphere which slows the object and causes it to drop from orbit varies in hight. It can be affected by temperature and solar activity. Many of these objects tumble as the orbit, making it very difficult to calculate exactly how drag will affect it. Finally many of these objects are complicated shapes, again making drag predictions difficult.

If you take all these factors together then it is not possible to give a precise prediction where such a re-entry will take place. It may be possible to know what day an object will re-enter. As the re-entry approaches then it might be possible to reduce that to an orbit or two, but we are talking about an object that circles the Earth in 90 minutes. Being out by even 1 minute gives an error on the ground of 445Km (277 miles).

The precise location of an uncontrolled re-entry is only known AFTER it has happened.

The vast majority of space junk does not make it to the ground and simply burns up in the atmosphere (larger objects are, as I said earlier, generally deliberately re-entered over the ocean). in the rare occasions when pieces do make it to the surface they poise a very small risk. Despite the impression city dwellers have that this planet is crowded with humanity, the reality is that most of it is unpopulated. In 56 years of spaceflight no one has yet been hit by a piece of space debris.

[freetoroam]

Even if it was possible to know exactly where and when this was going to happen (and I will come to that in a moment) exactly what should they be warning people about? What purpose would a "totally harmless bright light in the sky" warning actually serve?

Given that with this question you have shown that you do not know anything about the subject do you really think that giving a definitive statement on the subject such as the following was wise?

The problem with giving definitive statements on subjects you know nothing about is that they have a very good chance of being wrong. Guess what... you are wrong.

When there are controlled re-entries, such as a Soyuz capsule or a SpaceX Dragon, or the shuttle, or even a missile warhead, then the vehicle is re-entered over a precise, predetermined location so that the vehicle (or warhead) can land at the correct location. Since the vehicle is active it can manoeuvre and so constantly correct it's trajectory.

Then we have the deliberate, preplanned re-entries of retired satellites or spent booster stages, for example the Progress (and other) freighters that visit the ISS, the Mir space station or a spent shuttle fuel tank. These will be commanded to re-enter over the ocean so that any debris will not impact over land. Although not usually under control during re-entry they will be under a controlled trajectory until they hit the atmosphere and so the point of impact of any fragments can be pre-determined.

Finally we have the uncontrolled re-entries of space debris, such as was observed here. These are dead satellites or spent rocket stages which are not under control and have orbits which have decayed naturally.

This material is tracked and organisations such as NORAD will have a rough idea of when it will re-enter. The problem is that there are many variables involved in knowing exactly when such an uncontrolled re-entry will occur. The object may vent gas which could raise or lower it's orbit. The very sparse upper atmosphere which slows the object and causes it to drop from orbit varies in hight. It can be affected by temperature and solar activity. Many of these objects tumble as the orbit, making it very difficult to calculate exactly how drag will affect it. Finally many of these objects are complicated shapes, again making drag predictions difficult.

If you take all these factors together then it is not possible to give a precise prediction where such a re-entry will take place. It may be possible to know what day an object will re-enter. As the re-entry approaches then it might be possible to reduce that to an orbit or two, but we are talking about an object that circles the Earth in 90 minutes. Being out by even 1 minute gives an error on the ground of 445Km (277 miles).

The precise location of an uncontrolled re-entry is only known AFTER it has happened.

The vast majority of space junk does not make it to the ground and simply burns up in the atmosphere (larger objects are, as I said earlier, generally deliberately re-entered over the ocean). in the rare occasions when pieces do make it to the surface they poise a very small risk. Despite the impression city dwellers have that this planet is crowded with humanity, the reality is that most of it is unpopulated. In 56 years of spaceflight no one has yet been hit by a piece of space debris.

Thats why I am asking, cos i don`t know. But thanks, I do now. the bold bit is what I wanted to know really.

As for the first bit, they should inform us so we do not get untold IS THIS A UFO youtube videos.

Thanks for the info Waspie, I do not feel so thick now. Who knows, I could be as clued up as you one day.

Edited May 12, 2013 by freetoroam

[DONTEATUS]

peace on you freetoroam ! ITs good to read and learn from waspie,even when its a bit strict !