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Asteroid Didymos and the NASA probe in an illustration: At 1:14 a.m. German time on Tuesday, the crash is expected to occur
Photo: HANDOUT/AFP
On the night of Tuesday, a probe from the US space agency is to crash directly and intentionally into an asteroid for the first time, thereby changing its trajectory.
According to NASA, the "future security of the earth" is at stake in the mission called "Dart" (Double Asteroid Redirection Test).
It is "the first mission to try to use a direct experiment to push a dangerous object out of the way," says NASA Science Director Thomas Zurbuchen.
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If the mission is successful, the Nasa probe will hit the celestial body Dimorphos in the coming night.
But what exactly happens when the "dart" hits the asteroid can only be guessed at by experts: too little is known about the structure of the mini-asteroid.
Planetary researcher Martin Jutzi from the University of Bern told SPIEGEL: "Dimorphos can be anything from a monolithic object to a flying heap of rubble."
The composition plays a major role in the efficiency of the distraction.
Read more about this here .
Scientists are not currently aware of any asteroid that could be heading straight for Earth in the foreseeable future - but researchers have identified around 27,000 asteroids near Earth, around 10,000 of them with a diameter of more than 140 meters.
About 160 meters across, Dimorphos is a type of moon orbiting the larger asteroid Didymos.
The mission is designed in such a way that both asteroids should not pose any danger even after the impact of the probe, which only has one camera on board.
transmission of nasa
The probe sends one image per second to Earth of this spectacle.
Nasa wants to show the images in a live stream, and the transmission starts at 11:30 p.m. German time.
However, the space agency prepares viewers in an accompanying text: "In the hours before the impact, the screen will appear mostly black, with a single point of light".
This point is the binary asteroid system Didymos.
The closer the impact got, the larger the point of light became.
In addition, the images would be somewhat delayed in the stream.
At 1:14 a.m. German time, the probe should then collide with the asteroid.
After the impact, the transmission goes black due to a loss of signal, it said.
"After about 2 minutes, this stream becomes a replay showing the final moments before impact."
After the impact, Dimorphos' approximately 12-hour orbit is expected to be at least 73 seconds shorter and possibly up to 10 minutes shorter.
For the scientists, the real work then begins: investigating what exactly happened before, during and after the impact - and what that could mean for protecting the earth.
The impact of two mini-satellites is to be observed.
In 2024, the ESA mission "Hera" is to start for even more detailed investigation.
ani/dpa