Want to calculate when ANY satellite might deorbit? We have a Lifetime tool for that.
Please note: STK’s Lifetime tool is not intended to determine an exact time of decay, a specific geographical “impact point” or to what degree a satellite might survive its descent through the atmosphere.
The Lifetime tool estimates the amount of time a satellite can be expected to remain in orbit before atmospheric drag and other perturbations cause it to decay. A satellite is assumed to have decayed when its height of perigee drops below 64 km when atmospheric drag becomes too strong.
The Lifetime tool estimates the orbital lifetime of a satellite and provides the corresponding date of decay. It should be emphasized that although the Lifetime computations are based on sophisticated orbital theory and accurate environment models, the result is still an estimate. Due to the seemingly random 10% variation in atmospheric density and because of the difficulty in accurately predicting solar activity, satellite lifetimes cannot be determined with accuracy better than +10% of the actual lifetime. Furthermore, assumptions and simplifications made in order to produce a practical computer implementation of the lifetime theory introduce an additional degree of uncertainty in the final result.
To do this analysis:
-Download STK here -http://www.agi.com/product-explorer/?productid=12
-Open STK and create a new ‘scenario’
-Insert your satellite of interest from our Satellite Database
-Highlight your satellite in the object browser and select ‘Lifetime’ from the Satellite menu.
For more info on the parameters to enter into the tool, please refer to the help documention here: http://www.agi.com/resources/help/online/stk/source/stk/tools-11.htm
STK is a free tool and the Lifetime tool is part of STK Professional. You can get a 30-day evaluation here if you aren’t already a Professional user.
If you have further questions, please do not hesitate to contact our engineering support (support@agi.com).
Dear Senor Poley,
Thank you for looking after us and protecting our family from harm when NASA’s satellite crashed to Earth last month. Please look after us again as you find place for the Germany’s ROSAT satellite to crash too. The rainy season approaches and we need our barn so our alpacas don’t wet and they are hard to brush.
Warmest Regards,
Julio
Tierre del Fuego
Argentina
I understand that predicted entry is only estimated and there is no propulsion system which means it’s pieces could crash anywhere at 100mph and kill people.
The chance of it crashing into the sea are greater as there is much more sea than land, but there are also people out at sea. There are heavily populated areas in it’s path and they may be struck by it.
Does anyone have any control over it ?
When satellites are launched is any consideration given to people who may be beneath them when they crash to Earth?
Are there any plans to pay out for accidentally killing someone with it?
Senor Poley,
Once again we are saved. But, I am confused. My son, who is an Astronautics major at Virginia Tech in the United States told me the chance of ROSAT hitting me was 1 in 3200. I measured my barn and it is 1600 square feet. If I am 2 square feet than that means the odds of it hitting my barn was 1 in 2 so I was concerned for my llamas and alpacas.
And yet, once again my barn has not been hit. Which is good but I am beginning to wonder if my son should be majoring in something else, or should he go to a better school?
By the way, I spent Sunday night in the barn waiting for ROSAT and it did not come, but a baby llama did and so I have decided to name it “Holy Poley” after you.
Julio