Orbital Drag

We're in the midst of some major solar activity ( we just had another major
flare - X10 at 8.49PM ) all this affects the orbits of low Earth orbiting
satellites. How much has the altitude of ISS changed in the past week for
example? Is there a website that has this information?

Thanks

Steven

"Elysium Fossa" wrote in message
...
We're in the midst of some major solar activity ( we just had another
major
flare - X10 at 8.49PM ) all this affects the orbits of low Earth orbiting
satellites. How much has the altitude of ISS changed in the past week for
example?

About 1.3 km lower.

Is there a website that has this information?

Heavens Above maintains a one year graph of ISS' height:

http://www.heavens-above.com/issheig...ified&TZ =CET

Here are ISS' 2-line elements spanning nearly the past two weeks:

1 25544U 98067A 03289.80045139 .00017291 00000-0 19597-3 0 6533
2 25544 51.6286 127.3189 0006333 49.1059 138.5067 15.62479456280003

1 25544U 98067A 03292.80880787 .00015855 00000-0 17952-3 0 6686
2 25544 51.6293 112.1320 0006528 55.6987 145.5644 15.62579583280470

1 25544U 98067A 03296.82823387 .00021842 00000-0 24344-3 0 6928
2 25544 51.6291 91.8345 0006525 70.1335 77.6732 15.62732822281105

1 25544U 98067A 03299.83457123 .00022078 00000-0 24475-3 0 7066
2 25544 51.6304 76.6463 0006540 81.7868 71.1644 15.62863353281574

1 25544U 98067A 03301.86934052 .00035253 00000-0 38443-3 0 7131
2 25544 51.6300 66.3657 0006709 83.7464 5.6535 15.63011797281896

1 25544U 98067A 03302.10856481 .00035268 00000-0 38433-3 0 7144
2 25544 51.6309 65.1567 0006698 84.9995 271.3863 15.63029047281928

1 25544U 98067A 03302.50907943 .00035972 00000-0 39138-3 0 7154
2 25544 51.6299 63.1317 0006632 86.1231 5.4585 15.63060478281999

1 25544U 98067A 03302.83713926 .00033991 00000-0 36996-3 0 7165
2 25544 51.6301 61.4743 0006641 83.7135 55.1152 15.63079488282043

1 25544U 98067A 03303.20957148 .00073585 00000-0 78708-3 0 7174
2 25544 51.6313 59.5956 0006782 88.0121 348.0706 15.63182232282107

2-line elements are defined he
http://celestrak.com/NORAD/documentation/tle-fmt.shtml

and he http://www.satobs.org/element.html

The rate of decay doubled after the solar flare a few days ago, and doubled
again over the past day. Depending on the time-span of the observations, the
effects of a change in drag may take a few days to fully manifest themselves
in the elements.

Ted Molczan

"Elysium Fossa" wrote in message
...
We're in the midst of some major solar activity ( we just had another
major
flare - X10 at 8.49PM ) all this affects the orbits of low Earth orbiting
satellites. How much has the altitude of ISS changed in the past week for
example?

About 1.3 km lower.

Is there a website that has this information?

Heavens Above maintains a one year graph of ISS' height:

http://www.heavens-above.com/issheig...ified&TZ =CET

Here are ISS' 2-line elements spanning nearly the past two weeks:

1 25544U 98067A 03289.80045139 .00017291 00000-0 19597-3 0 6533
2 25544 51.6286 127.3189 0006333 49.1059 138.5067 15.62479456280003

1 25544U 98067A 03292.80880787 .00015855 00000-0 17952-3 0 6686
2 25544 51.6293 112.1320 0006528 55.6987 145.5644 15.62579583280470

1 25544U 98067A 03296.82823387 .00021842 00000-0 24344-3 0 6928
2 25544 51.6291 91.8345 0006525 70.1335 77.6732 15.62732822281105

1 25544U 98067A 03299.83457123 .00022078 00000-0 24475-3 0 7066
2 25544 51.6304 76.6463 0006540 81.7868 71.1644 15.62863353281574

1 25544U 98067A 03301.86934052 .00035253 00000-0 38443-3 0 7131
2 25544 51.6300 66.3657 0006709 83.7464 5.6535 15.63011797281896

1 25544U 98067A 03302.10856481 .00035268 00000-0 38433-3 0 7144
2 25544 51.6309 65.1567 0006698 84.9995 271.3863 15.63029047281928

1 25544U 98067A 03302.50907943 .00035972 00000-0 39138-3 0 7154
2 25544 51.6299 63.1317 0006632 86.1231 5.4585 15.63060478281999

1 25544U 98067A 03302.83713926 .00033991 00000-0 36996-3 0 7165
2 25544 51.6301 61.4743 0006641 83.7135 55.1152 15.63079488282043

1 25544U 98067A 03303.20957148 .00073585 00000-0 78708-3 0 7174
2 25544 51.6313 59.5956 0006782 88.0121 348.0706 15.63182232282107

2-line elements are defined he
http://celestrak.com/NORAD/documentation/tle-fmt.shtml

and he http://www.satobs.org/element.html

The rate of decay doubled after the solar flare a few days ago, and doubled
again over the past day. Depending on the time-span of the observations, the
effects of a change in drag may take a few days to fully manifest themselves
in the elements.

Ted Molczan