My rant this week is about how TV shows disseminate horribly inaccurate information about satellites. I just watched an old episode of The West Wing where a war between India and Pakistan was imminent in the Kashmir region. The U.S. general told the president that they had just deployed a satellite over the “northern Asian subcontinent” to monitor the situation. This is wrong on two levels.
First, to position a satellite over a fixed spot on the surface of the earth, it must be over the equator. That’s because a satellite in a circular geostationary orbit must orbit around the center of mass, i.e. the center of the earth. If that doesn’t compute with you, just take my word for it, or read up on orbital mechanics. Kashmir is over 2000 miles north of the equator, so it’s a no go.
Second, a geostationary orbit is about 22,000 miles above the surface of the earth. You can’t see much of anything from there except the weather. That’s where weather satellites hang out. Spy satellites and most other orbiting stuff we’ve sent up are in low earth orbit, somewhere around 200 to 300 miles above the surface. With very powerful cameras you can see things on the surface from there if the weather isn’t too bad. They are normally placed at an angle to the equator so that they can travel at various latitudes, although still centered on the center of the earth. The problem is that those satellites zip around the earth very fast, about 90 minutes per orbit. They are only over a particular spot for a minute or two and on the next orbit, when they are at the right longitude, they’ll be at a different latitude, so they won’t pass over that spot every 90 minutes. It cam take days to get there the next time and during the minute they are there, the weather may be bad.
Other shows do this all the time, too. The show 24 was awful about this. It’s still happening and it’s a problem. You may have heard of “the CSI effect” where some jurors expect police and FBI to be able to do all the fancy “scientific” things they see police on TV that are actually impossible or unrealistic. This may fall into that category. I even know of one general who asked a satellite engineer to position a satellite over a spot like that. Learn the laws of physics, TV writers! Some members of the public may expect unrealistic things of our military or law enforcement. Just because you saw a nice animation on TV, that doesn’t mean it’s possible.