Fans identify US spy satellite behind President Trump's tweet

Amateur satellite trackers say they believe an image tweeted by President Trump on Friday would come from one of the most advanced spy satellites in the United States.

The image almost certainly comes from a satellite called USA 224, according to Marco Langbroek, a satellite follower based in the Netherlands. The satellite was launched by the National Reconnaissance Office in 2011. Nearly everything is listed there, but according to Mr. Langbroek, because of its size and orbit, most observers believe that the USA is 224 39, a multi-billion dollar KH-11 reconnaissance satellites.

"It's actually a very large telescope, similar to the Hubble Space Telescope," Langbroek said. "But instead of looking at the stars, he looks at the surface of the Earth and produces very detailed images."

The image tweeted Friday by Trump, showing the consequences of an accident at the Iranian Space Center Imam Khomeini, was so detailed that some experts doubted that it could have come from a satellite located above the planet.

Iran was preparing to launch a rocket called Safir with a small satellite on board, but experts believe that it exploded during refueling. The image showed a sharp handwriting painted on the edge of the launch pad, the burnt truck that had been used to move the rocket and other details.

Trump seemed to use the sensitive recognition image to drag the Iranians. "The United States of America has not been involved in the catastrophic accident in the preparations for the final launch of the Safir SLV launch at Semnan's launch site number 1 in Iran", tweeted the president. "I wish Iran all the best and good luck in determining what happened at Site One."

But a small community of amateur satellite followers was much more interested in photography than in words. These individuals use telescopes to watch satellites whistling in the sky and they know where most of them are – even those classified as those of USA 224. "They are very bright in the sky and easy to find. " Michael Thompson, a graduate student in astrodynamics at Purdue University, spotted the satellites in her spare time. Once a satellite is seen, it is relatively easy to determine exactly where it will be in the future. "Using mathematics to calculate an orbit is really easy," he says.

Thompson was one of the first to use a database of amateurs on satellites known to point the finger at USA 224. He showed that it was flying over the Iranian space center shortly after the accident.

Langbroek went even further. He was able to reconstruct the picture taken by USA 224 by comparing the obliquity of the circular launch pad in the image tweeted by Trump. His calculation shows that the picture was taken from the perspective of USA 224. Langbroek and another online researcher, Christiaan Triebert, also used the shadows worn by the towers around the launch pad as sundials, allowing them to check the time at which the photo was taken.

Both techniques suggest that the images were broken by USA 224, which flew near the site at 14:14. local hour. "The match was perfect, basically," Langbroek said.

Prior to the analysis, some experts suspected that the image contained in Trump's tweet could come from a drone or a spy plane.

"When I saw the picture, it was so clear and so high resolution that I did not think it could come from a satellite," says Melissa Hanham, satellite imaging expert and Deputy Director of the Nuclear Network, Vienna, Austria. But she finds the new analysis compelling. "Since the satellite is in position at that time, it is now very likely that it will be [the source of the picture]," she says.

Hanham is surprised that a satellite can provide such clear images. The spy satellites have to scan the earth's atmosphere, which is a bit like trying to look at objects in the bottom of a pool. They must also take their photos whistling in the sky. Both effects can blur the details of the images.

"I'm scratching my head and I'm curious how they take into account the effects of the atmosphere and the movement of objects," she says.

And she says that she thinks she's not alone. Others will try to use the image to learn more about how USA 224 works. "I imagine that the adversaries will look at this picture and proceed with reverse engineering to understand the operation." the sensor itself and the type of post-production techniques they use, "she explains.

Hanham asks if Trump's tweet about the Iranians was worth the information that this image provides to other nations, but she adds, "It's his decision as president."

Copyright NPR 2019.