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The battery pack after being dropped from the ISS (2021)

Photo: NASA

First of all, the facts: In March 2021, NASA experts dropped a disused battery pack from the International Space Station (ISS) using a large robotic arm.

The nickel-hydrogen accumulators had become unnecessary after a conversion of the station's solar panels.

It was the largest piece of space junk ever disposed of in this way.

The idea is that the batteries would orbit the earth, slowly sinking - and eventually burning up in the atmosphere.

Now it should soon be that time.

The European Space Agency (Esa) is assuming a date that cannot yet be determined on Friday.

Experts around the world have been tracking the scrap package since it was exposed.

The exact time of the crash depends, among other things, on the current solar activity - because this determines how far the thinnest remnants of our atmosphere reach into space.

And this in turn determines how much objects are slowed down by friction as they orbit our Earth.

Now to interpret what actually happens every day: The battery pack has a lot of mass at almost three tons.

However, objects of this dimension regularly fall from their orbit towards Earth.

Just about two weeks ago, the old European environmental satellite ERS-2 burned up in its atmosphere.

There was no damage on earth.

The "Bild" newspaper published an article on Thursday under the headline "Battery rain from space falls on Germany."

It spoke of “danger in several cities” in Germany.

That's pretty nonsense.

The newspaper cites the Federal Ministry for Economic Affairs and Climate Protection as the source.

If you ask there, the matter sounds much less dramatic.

A spokeswoman tells SPIEGEL that a threat to Germany is “very unlikely.”

It relies on an assessment by the space situation center, which is operated jointly by the Bundeswehr and the German Aerospace Center (DLR) in Uedem, North Rhine-Westphalia.

Traveling on the ISS orbit

Even when you call the space situation center, there is little sense of excitement.

Likewise when you talk to those responsible at Esa.

The fact is: the battery pack will crash.

It is considered possible that some of the encapsulated batteries could survive the fall through the atmosphere.

But there is no indication that Germany is particularly at risk as a result.

When space debris is dropped from the ISS - before the battery pack, for example, there was a large ammonia tank in 2007 or a disused Russian space suit in 2006 - it travels on the same path as the space station.

With an orbital inclination of 51.6 degrees, the elements fly around the earth in an easterly direction approximately once every hour and a half.

This means that the space station - and the junk it releases - regularly flies over all areas of the planet between 51.6 degrees south and 51.6 degrees north latitude.

When the sky is clear, it can be seen as a bright point of light in the sky.

The railway poses a hypothetical threat to Germany - because if you draw 51.6 degrees north on a map, this line runs right through the country.

So theoretically, and really only theoretically, the garbage could come down south of this line.

Crash in the water likely

In practice, however, it is currently not even clear which orbit around the earth will be the last for the battery pack.

That's why no one can say whether it will even be over Germany when it crashes.

Probably not.

“If, contrary to expectations, there are indications that Germany is affected, the existing crisis response mechanisms of the federal and state governments will be used to respond appropriately to a possible threat,” writes the Ministry of Economic Affairs.

That's reassuring.

Especially since the probability is not zero, but almost: more than 70 percent of the earth is covered with water.

From what can be assumed, the space debris will end up in the ocean this time too - if it even reaches the surface.

There are a lot of things happening in the world right now that should worry us.

The ISS battery pack is not one of them.