A giant satellite has gone out of control and may crash on Earth this weekend

"Statistically, there is a 1 in 3,200 chance that one person somewhere in the world will be hit by a satellite crash," says Nick Johnson, chief scientist of NASA's Space Debris Program.

"Statistically, there is a 1 in 3,200 chance that one person somewhere in the world will be hit by a satellite crash," says Nick Johnson, chief scientist of NASA's Space Debris Program.

A broken 6.5 ton satellite, named URAS, is making its way to Earth. The problem is that NASA does not know exactly when and where it might hit. They also do not know how many percent of the satellite will survive the hot passage through the Earth's atmosphere.

The estimate now is that the satellite will fall between Thursday (tomorrow) and Saturday. "Statistically, there is a 1 in 3,200 chance that one person somewhere in the world will be hit by a fall from a satellite," says Nick Johnson, chief scientist of NASA's space debris program at a press conference held last Friday. That means there is a very low chance that someone will be hurt by the fragments.

Johnson mentions that "During the entire 54 years of the space age, there were no reports of a single person being injured by any object that returned from space.

The 10-meter-long satellite, designed to study the Earth's upper atmosphere, flies in an orbit that includes six continents and three oceans. According to Johnson, the expectation is that the satellite will fall out of control in late September or early October.

While most of the spacecraft's material is expected to burn up during re-entry into the atmosphere, it is likely that some large pieces will reach the ground. Currently, estimates of the fracture field expected during the event speak of a radius of 800 kilometers and its location may be anywhere in the low and middle latitudes.

"We know with 99.9% certainty that it will enter the atmosphere at latitudes between 57 degrees north and 57 degrees south, meaning it covers the latitudes from Canada to the southern tip of South America and of course corresponding parts of Europe, Asia and Africa, and Australia," says Meige. and Michael Duncan, vice president of the Space Risk Situation Room at the US Air Force Strategic Command. "This is the best estimate that can be provided at this time."
There are about 26 components on the satellite that are large enough to survive burning in the atmosphere and reach the ground, the largest of which weighs over 150 kg.
"Returning satellites is a common phenomenon" says Johnson. Last year, for example, there was an average of one object per day that fell uncontrolled into the atmosphere, meaning that it was impossible to know where and when they would fall - and in total it is 75 tons of spacecraft and launcher remains that fell to Earth.

By comparison, URAS weighs less than six tons, Johnson says, "so it's a small percentage of the mass of satellites that fall to Earth.
Most of the satellites were much smaller than URAS and they burned up completely in the atmosphere.

The URAS satellite was launched from the space shuttle Discovery in 1991. To give a sense of how big the satellite is, we will explain that it completely filled the shuttle's cargo deck. It had ten scientific instruments on it to test the chemistry of the upper atmosphere and measure water vapor and other components. He checked the condition of the hole in the ozone, and surveyed the amount of aerosols in the atmosphere. In 2005 he was decommissioned. It was not planned to return to the space shuttle, says Paul Hertz, chief scientist at NASA's Science Mission Directorate. Hertz said that NASA will take care of updating the public about the possibility of debris falling from the satellite, and he will be the person responsible for the update at this address.

The Space Command will monitor the satellite and provide updates on when and where the satellite will fall, and will provide predictions regarding the risk of damage if the satellite crashes on land.

Although there are no dangerous substances on the satellite, unlike the hydrazine that was in large quantities in the NRO spy satellite that was shot down in 2008, to prevent contamination of the Earth - NASA still asks anyone who finds remnants of the satellite not to collect it and to inform the local authorities. But anyone who finds himself out of the path of the fall may win a spectacular show. says Johnson.
"It is a fairly large vessel," he said, "it will be visible even in daylight, the chances are that it will end its life in the ocean, and therefore this appearance will perhaps be revealed to passing airplane passengers. We have had such reports before. Since we don't know when it will crash we can't raise people's expectations and tell them to go watch the spectacle from their backyard. It will be a kind of serendipitous event.” Concluded.

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