How closely can ground control monitor astronauts aboard the ISS. Are there cameras or microphones that the ground can use to see and hear what's happening, or are they reliant on the crew to relay what is going on in terms of astronaut activity and movement?

If an astronaut wanted to do something like a practical joke on ground control and they needed to talk and hide their movements, would they be able to do that unnoticed?

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    $\begingroup$ @uhoh Thanks, any answers to your edit will answer the aspects of the initial question that interested me $\endgroup$
    – lijat
    Commented Oct 26, 2018 at 12:48
  • $\begingroup$ It's a good question, I've wondered about this as well. $\endgroup$
    – uhoh
    Commented Oct 26, 2018 at 12:49
  • $\begingroup$ en.wikipedia.org/wiki/List_of_cameras_on_ISS - I don't know if this includes security cameras, or if there even are internally monitored security cameras. Watching tours of the ISS I don't see anything like an "IP Camera" system that a traditional stop-n-go would use. Security cameras were popular as early as 1987 though, CCTV was using facial/licence plate recognition by 1997, the ISS was launched in 1998. I would expect there to be something akin to a 7-11's security cameras. $\endgroup$ Commented Oct 26, 2018 at 13:01
  • $\begingroup$ It's going to be hard to prove a negative, but there are no internal cameras or microphones that the crew does not have control of. The ground has total control of the external cameras. $\endgroup$ Commented Oct 26, 2018 at 13:46
  • $\begingroup$ The question of "can" may need to be specified if you mean technical ability or process ability. I suspect that normal procedures are to request permission before activating interior cameras ("can we come aboard?"), but that it could be done without permission if necessary. $\endgroup$
    – BowlOfRed
    Commented Oct 26, 2018 at 15:56

2 Answers 2


Note: This answer applies to the US side of the ISS

The ISS internal video cameras are simply Commercial Off The Shelf (COTS) camcorders. They interface with the video distribution system by plugging into Internal Camcorder Ports located throughout the pressurized modules. These ports communicate with Common Video Interface Units (CVIUs) which in turn communicate with Video Switching Units (VSUs). Camera ports. The ISS has camera ports (part of the structures and mechanisms system), both internal and external, for connecting cameras to the ISS. The internal camera ports are for handheld commercial camcorders. The external camera ports (14 in all) are for the ETVCG's.

(emphasis mine)

enter image description here

International Space Station Evolution Data Book (NASA/SP-2000-6109/VOL1/REV1)

The ground has control of the CVIUs and VSUs, but no control over the COTS camcorders. If the crew does not want video to be taken, there is nothing the ground can do about it other than ask nicely.

enter image description here

Photo Credit: NASA

  • $\begingroup$ Of course, if the ground ask nicely and the crew disobey, their chances of ever getting into space again drop to zero. $\endgroup$
    – Innovine
    Commented Jul 7, 2021 at 21:25
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    $\begingroup$ @Innovine Clay Anderson (en.wikipedia.org/wiki/Clayton_Anderson) had a big fight with MCC while on the ISS, got put on non-flight status, and managed to get back into their good graces and fly again. Fascinating description in his very frank memoir The Ordinary Spaceman nebraskapress.unl.edu/nebraska/9780803262829 $\endgroup$ Commented Jul 7, 2021 at 21:31


There are interior Canon XF305 (and now XF-705 as of 2021) camcorders all throughout the USOS portion of Station, but the crew could manually turn them off, unplug them, place the lens cap on them, or face them at the wall if they so desired and Mission Control could do nothing about it.

Generally, the crew leaves the cameras plugged in and the physical power switch on at all times. The cameras are powered off by ground-based flight controllers at the end of each work day and only powered back on starting at morning DPC (Daily Planning Conference). Mission Control generally asks permission to "come aboard" prior to activating the cameras.

During the workday, there are six simultaneous video downlinks used for "over the shoulder" situational awareness for flight controllers or science teams in order to assist the crew members in their planned activities. The "six pack" video is available whenever there's Ku-band coverage.


There's no audio automatically downlinked from the ISS. Crew members have a PTT handset that's wired into the ATU (Audio Terminal Unit) panel located in each module. They can talk to Mission Control with the blue handset/microphone shown below whenever there's S-band or Ku-band coverage.

enter image description here (image source)

If a crew member is performing a task in a glovebox or during EVA, they can wear a VOX headset which transmits whenever a certain noise threshold is exceeded. That way it's not constantly broadcasting white noise, and when they need to speak they don't have to free up a hand for the PTT.

enter image description here


Any SG voice loop and video downlink can be privatized so only a small subset of "need to know" personnel can hear/view. This is done for any medical experiment procedures a crew member is performing, or for sensitive research that may be proprietary. One example that always gets voice/video privatized is Rodent Research performed on the ISS. There are special subsets of each flight control discipline that handles those procedures.

  • $\begingroup$ Maybe you can answer this old question: space.stackexchange.com/q/44705/6944 $\endgroup$ Commented Feb 8 at 23:38
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    $\begingroup$ @OrganicMarble Unfortunately that's more of a GC/CRONUS question, since they're the ones actually putting the privatization in place. My concern as an OC was just "is it in place?" $\endgroup$
    – Doresoom
    Commented Feb 8 at 23:57
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    $\begingroup$ Ditto, as a MCC instructor, hence the question. $\endgroup$ Commented Feb 9 at 2:06

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