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34

This appears to be a garbled recounting of a problem that occurred during STS-1 entry due to a mis-match between predicted and actual hypersonic pitch trim. Image Source All that happened was that the body flap (see aft of Orbiter on diagram) extended 5 degrees more than predicted (which did cause the body flap to see higher heating than predicted as well)...


6

I want to offer some input to the above --- I'm thrilled in the level, depth, and knowledge reflected in the questions and discussion. This has been eye opening for me.... Citizen Scientist has a new meaning for me! Regarding 300 km vs 450 km. In my research I deploy, operate, and use data from scientific cameras. The data I was using for Steve came from a ...


5

It's an internal reflection. I wish I knew of what exactly, but here's the same line of green LEDs in a different picture. Some gadget in the cupola. I am not promising this is the source, but the Robotics Workstation (mounted in the cupola) has a lot of green LED illuminated buttons on it and you can see them reflecting all over the place here.


4

An excellent summary of the mission can be found here: https://earth.esa.int/web/eoportal/satellite-missions/a/atlas SEPAC involves the firing of a 1.6 Å 7.5 kV electron beam accelerator from the Shuttle bay to study a variety of phenomena related to vehicle charging and charge neutralization, atmospheric interactions, and virtual-antenna operation. The ...


4

A "flux tube" is a magnetically-confined conduit that allows charged particles to flow between one place in a planet's magnetosphere and another. An "L-shell" is a subset of a planet's magnetic field lines that cross the planet's equator (for most planets, anyway) at the specified number of planetary radii from the planet's center. In a ...


3

I think you're right. A finite pair of charged screens, with zero net charge, can't create an infinite potential well; the potential far away from the device must return to zero, which means that the propelled particles must get decelerated to their original velocities, taking back the momentum they initially provided. It seems that Zubrin has taken a ...


2

In a later (independant) interview with Eric Donovan he states the height was 450km. I suspect that in the presentation to the ESA meeting he should have said 300 miles which is 482 km very close to the altitude of the SWARM A satellite at the time rather than 300 km. All the online articles including wikipedia appear to be clones of the ESA presentation and ...


2

Science Magazine carried a March 2018 research article about this: Elizabeth MacDonald et al "New science in plain sight: Citizen scientists lead to the discovery of optical structure in the upper atmosphere" (hopefully not paywalled) Much of the observation are Earth based (including some by the Berkeley group), but the Swarm LEO satellites also ...


1

Editor's note: I'm maintaining here information from user Roger until he decides to migrate on his own. Answer to the question: "Can you add a link or citation that confirms that the temperature of Steve's ions was actually measured by the TII?" Have a look at the presentation from Eric Donovan at the 4th Swarm science meeting in Banff: http://www.esa.int/...


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