Takehome point: There turns out to be at least something that this incredibly hardy species is believed not to have survived. That would be the crash land on the moon of Israeli satellite Beresheet with tardigrades aboard.
According to Wired, there were water bears (tardigrades) aboard:
Someone decided to test whether the water bears (tardigrades) could have survived:
Traspas and her supervisor, Mark Burchell, a planetary scientist at the University of Kent, wanted to find out whether tardigrades could survive such an impact—and they wanted to conduct their experiment ethically. So after feeding about 20 tardigrades moss and mineral water, they put them into hibernation, a so-called “tun” state in which their metabolism decreases to 0.1% of their normal activity, by freezing them for 48 hours.
They then placed two to four at a time in a hollow nylon bullet and fired them at increasing speeds using a two-stage light gas gun, a tool in physics experiments that can achieve muzzle velocities far higher than any conventional gun. When shooting the bullets into a sand target several meters away, the researchers found the creatures could survive impacts up to about 900 meters per second (or about 3000 kilometers per hour), and momentary shock pressures up to a limit of 1.14 gigapascals (GPa), they report this month in Astrobiology. “Above [those speeds], they just mush,”
Traspas says. Jonathan O’Callaghan, “Hardy water bears survive bullet impacts—up to a point” at Science
The water bears were above mush speed, it appears.
What impact does the test have on panspermia, the hypothesis that life might travel between planets via comets?
Traspas, however, says it shows panspermia “is hard,” but not impossible. Meteorite impacts on Earth typically arrive at speeds of more than 11 kilometers per second. On Mars, they collide at least at 8 kilometers per second. These speeds are well above the threshold for tardigrades to survive. However, some parts of a meteorite impacting Earth or Mars would experience lower shock pressures that a tardigrade could live through, Traspas says.
Jonathan O’Callaghan, “Hardy water bears survive bullet impacts—up to a point” at Science
Well, when we meet up with the aliens, they could well be water bears (tardigrades).