ISS Ammonia Vent (May 3, 2017)
Why Space Exploration Stack Exchange recommends it
Space Stack Exchange users link it as a real example of material being vented from the ISS and as a visual of station hardware like the ammonia radiators and antennas.
Recommended by 0 people across 0 different months, 2016 to 2020.
What it is
A short clip from Spaceflight101 showing a stream of frozen ammonia escaping from the International Space Station during a planned vent-down on May 3, 2017. Ground controllers vented a radiator valve module on Loop B of the External Thermal Control System while trying to isolate a suspected slow leak. The footage is sped up 10x.
What people said
Cites Organic Marble · 2016-06 · Space Exploration Stack Exchange · on “Do antennae on the ISS have to constantly move to maintain data links?”
The US side of the ISS has a number of antennas to support its rather complicated comm system. Most visible are the two Ku-band High Gain Antennas which are 6 foot diameter azimuth/elevation gimbaled dish antennas mounted on the Z1 truss segment (near the center of the ISS truss). These antennas are sometimes referred to as SGANTs (Space-to-Ground ANTennas). [LINK] For most of its life, the ISS only had one SGANT. A second one was carried up on one of the later shuttle missions [LINK] . This system carries the video and experiment data to the ground and would normally be gimbaling continuously to point at the selected geosynchronous comsat (i.e. TDRS). You can see one tracking a TDRS satelli
Cites user12102 · 2017-06 · Space Exploration Stack Exchange · on “How do satellites communicate with a relay satellite?”
This excellent answer [LINK] discusses moving directional antennas in LEO that talk to TDRS. They are on the ISS. It also links to this video: [this video]
Cites user12102 · 2017-08 · Space Exploration Stack Exchange · on “What are the orbital mechanical consideration behind hand-launched nanosatellites from the ISS?”
@RomanReiner and all the photovoltaic panels and ammonia-filled thermal radiator panels, and high-gain antennas (some shown in [this video] ) are all designed and rated to accept impacts from astronaut-thrown and returning 5kg cubesats? That's not considering that the velocity difference could change different after a few orbits - the Earth is not a perfect monopole. If you think it's safe to throw things off the ISS any way you feel like because nothing could go wrong and so there are no rules, consider posting that as an answer!
Cites Apaiss · 2020-05 · Space Exploration Stack Exchange · on “H2 and CO2 ventilated outboard of the ISS, could become ice flakes in the extreme temperatures outside the ISS?”
Outside the ISS in the orbital night, the temperature can reach -250 degrees Fahrenheit (-157 degrees Celsius). The ECLSS (Environmental Control System and Life Support System), more specifically the OGA sub-system (Oxygen Generation Assembly) vent overboard hydrogen in the electrolysis process to produce oxygen from water, and the sub-system CDRA (Carbon Dioxide Removal Assembly) vent CO 2 overboard ISS, too. At orbital night temperature, or even in the penumbra / terminator area, could these gases (I'm not sure if the H 2 is maintained gaseous or liquid before it is about to be vented) become flakes of ice when ventilated outboard? Could CO 2 become flakes of dry ice? (EDITED by the commen