Unanswered Questions
12
votes
0answers
179 views
What's falling off the Shenzhou/Long March stack?
Watching the launch of the Shenzhou-11 mission on a Long March 2F, I noticed a number of items falling off the exterior of the rocket. I'm used to seeing chunks of ice sheet coming off of cryogenic ...
11
votes
0answers
271 views
What happens next if the root cause of one rocket failure won't be identified?
Supposing that in a rocket failure engineers don't find what the root cause was, what will happen next?
In general if the root cause will never be fully understood is there a law, rule, or standard ...
11
votes
0answers
511 views
What is the value of the cross-track angle between the two designated CRS-4 first stage recovery zones?
For the SpaceX Falcon 9 launch on its Dragon/CRS-4 cargo delivery mission to the International Space Station, according to Spaceflight 101, two downrange safety zones have been identified:
The SpX-...
9
votes
0answers
94 views
How bright is a rocket launch?
How bright (in Watts, preferably, or lumens) is the plume from a rocket launch (e.g. a SpaceX launch)? Obviously in its direction of travel it isn't particularly bright, but what is its effective ...
9
votes
0answers
523 views
How does QUESS, China's quantum communications satellite, relay entangled signals?
China launched the Quantum Experiments at Space Scale (QUESS) satellite today, which will be used for quantum communications between China and Europe. Popular Science describes the science package as ...
9
votes
0answers
177 views
At what altitude does transonic compressibility become a non-issue?
I know that on the forthcoming SpaceX attempt at sea landing the first stage, they have added hypersonic fins to the first stage. I was curious as to what altitude transonic compressibility is an ...
8
votes
0answers
89 views
How are remove before flight (RBF) pins made?
The CubeSat standard (CubeSat Design Specification Revision 13) requires that CubeSats have a remove before flight (RBF) pin that "shall cut all power to the satellite once it is inserted into the ...
8
votes
0answers
102 views
What is the process for allocating GEO slots to commercial satellites?
Building off of this previous question, is there a more detailed summary anywhere of the process that a commercial satellite would have to go through to obtain a GEO slot?
The documentation I have ...
8
votes
0answers
96 views
Measuring the pressure and temperature of Pluto's atmosphere using stellar occultations
Is this primarily done analyzing the Voigt profiles absorption bands on background of stellar spectra or on re-emission bands of atmospheric compounds?
Assuming Pluto's atmosphere behaves like an ...
8
votes
0answers
550 views
Online Porkchop Plotter
Is there an online tool available to calculate porkchop plots at arbitrary resolutions? Real world only please -- I am aware of the tools available to do this for, say, KSP.
7
votes
0answers
65 views
How many orbits will it take for Santa to deliver all the presents?
This year Santa has decided to try a new strategy to deliver presents which he hopes will require less physics-defying magic, since magic is in short supply these days. Instead of personally flying ...
7
votes
0answers
56 views
How could we make a fair comparison between space rockets regarding their payload mass in low Earth orbit and Earth escaping?
I was searching for comparisons between space rockets regarding their payload mass in low Earth orbit and Earth escaping. First one to see capability of the space booster (the first stages) and second ...
7
votes
0answers
106 views
Understanding formula for geocentric position of Moon
I am trying to understand a basic formula in a Celestial Mechanics reference. The formula is for the position of the Moon in a geocentric frame. The reference claims in line (981) that this should be ...
7
votes
0answers
70 views
Do different generations of Soyuz use different launchpad infrastructure?
The Soyuz family has many variants. Do any of them require different launchpad infrastructure? If multiple active variants require different infrastructure, how are the logistics of that handled? Do ...
7
votes
0answers
132 views
Purpose of hemisphere under shuttle nose cone (Enterprise)
I noticed a small hemisphere protruding from the dorsal side of the Enterprise space shuttle's nose cone, forward of the front landing gear. I have no clue what its purpose is but am far from an ...
