Viewing profile — horstbort

You are never really floating freely, all gravitational wells extend to infinity. The curvature just becomes really small so the resulting acceleration is infinitesimally small too…

There is always microgravity, i.e. residual acceleration due to drag and thrusters, and especially vibrations. Worst offenders are actually the astronauts, especially when they wor…

Thankfully, the same measurement technique can be used to measure e.g. gravitational fields, and there are already devices available on the market which surpass classical gravimete…

That's the gist of it, yes. The big advantage atom interferometers have over classical IMUs is that they do not need to be recalibrated every so often. They are thus often called "…

Related discussion a few weeks ago: https://news.ycombinator.com/item?id=40692333

You don't need any helium or nitrogen here, cooling happens only by laser cooling and evaporative cooling from magnetic or optical traps. The atoms are perfectly insulated in an ul…

There is no liquid nitrogen involved here. The instrument from the article is actually rather big, current generations of quantum IMUs are roughly half this size with lots of room …

Obligatory: https://git-man-page-generator.lokaltog.net/

Permanent magnets are typically a no-go, because these sensors employ matter-wave interferometry, i.e. interference between atoms. Those unfortunately do not only react to gravity,…

Author here. Yes, Doppler Cooling is the first step used in the experiment, in a Magneto Optical Trap [0]. It is followed by Polarization Gradient Cooling [1] to overcome the Doppl…

Correct, that's the main problem there. Demanding experiments are even carried out when the astronauts are sleeping, they also tend to vibrate ;-)

They're building something similar in Hannover: https://www.hitec.uni-hannover.de/einsteinelevator.html

Hey, that's my experiment! :-) So great to see that here on HN.

Hi, drop tower user here :-) Three drops per day is due to 20 min preparation, 90 min evacuation, 30 min to refill with dried air, 20 min recovery. The is indeed long, which was no…

Hi, long-time drop tower experimenter here :-) One very good reason to choose a drop tower over the vomit comet is microgravity quality, i.e. residual acceleration and vibrations. …