I have worked as a scientist for over 20 years. My area of expertise is imaging, robotics, computer vision and AI. I have worked on a few projects involving satellite imagery.
Here's my take.
Weather satellites come in two flavors; polar and geostationary. The geostationary ones revolved around the Earth at the same rate as the Earth rotates, meaning they "hover" above a fixed point above the Earth. These satellites give you a multi-spectral image every 1-5 minutes. The resolution is typically not very high as these satellites are about 36,000 km out from the Earth (the position where the orbital velocity is such that the satellite orbits as fast as the planet rotates). I would typically work with images that had a maximum resolution of 1x1 km. Some channels (water vapor) had a lower resolution of 4x4 km. Some of these channels would work in the thermal region of the spectrum (true infrared) whereas others would be in the near infra-red spectrum (wavelengths only slightly longer than visible red). Could these satellites register an infrared laser? This depends on the wavelength. Most of the infrared part of the spectrum is absorbed by the atmosphere, meaning you could only use wavelengths closer to visible light, perhaps NIR (near-infrared).
From a resolution perspective, it is very unlikely you could observe such a laser beam with a geostationary satellite. If the laser wavelength is suitable and the light scatters enough for the sensor to pick up the light it is possible. (Think shining a laser in a dusty room; you can only see the beam when light deflects off of smoke or other small particles) I would have to look at the numbers on how much lasers scatter at those wavelengths. I think it is unlikely.
Now, with regard to polar satellites; these are satellites that are in a much lower orbit, typically only a few hundred kilometers up. They orbit from pole to pole to pole... etc. in around 90 minutes. (Lower orbits are always faster; if you speed up in a lower orbit, you reach a higher orbit. If you slow down in your orbit, you get into a lower orbit (here's the counterintuitive part), making you orbit faster.
Polar satellites cover the complete surface of the planet eventually, because the planet rotates "beneath" them. In 24 hours you would cover the planet in about 16 equidistant parallel strips. (Imagine taking a beach ball and wrapping a ribbon from top to bottom and back while rotating the beach ball slowly) Depending on the width of these strips, you could theoretically cover the whole beach ball. Typically, however, these strips observed by polar satellites are not very wide, because we want a high imaging resolution. Typical polar satellites cover the entirety of the planet's surface in 3-4 days.
Here we immediately see the trade-off between polar and geostationary satellites: One makes it possible to observe the same location continuously, but at reduced detail. The other allows for much higher detail levels (down to 3-4 inches), but you can not observe all of it at the same time. The solution is of course to have many polar satellites to cover all of the surface within a day or less.
Could you observe a near-infrared/visible laser with a polar satellite? If the satellite is positioned correctly (luck) and the scattering of the laser beam is high enough for the imaging sensor to pick up, then yes. Again, I am not sure if the scattering would be high enough.
However, I know thermal imagers exist that use infrared wavelengths from between 3 to about 600 µm.
I would need to have a look at the source data to find out more. Particularly the directionality of the beam would be of interest. Perhaps, given the time of recording, one could match the beam to a known military satellite.
I have worked as a scientist for over 20 years. My area of expertise is imaging, robotics, computer vision and AI. I have worked on a few projects involving satellite imagery.
Here's my take.
Weather satellites come in two flavors; polar and geostationary. The geostationary ones revolved around the Earth at the same rate as the Earth rotates, meaning they "hover" above a fixed point above the Earth. These satellites give you a multi-spectral image every 1-5 minutes. The resolution is typically not very high as these satellites are about 36,000 km out from the Earth (the position where the orbital velocity is such that the satellite orbits as fast as the planet rotates). I would typically work with images that had a maximum resolution of 1x1 km. Some channels (water vapor) had a lower resolution of 4x4 km. Some of these channels would work in the thermal region of the spectrum (true infrared) whereas others would be in the near infra-red spectrum (wavelengths only slightly longer than visible red). Could these satellites register an infrared laser? This depends on the wavelength. Most of the infrared part of the spectrum is absorbed by the atmosphere, meaning you could only use wavelengths closer to visible light, perhaps NIR (near-infrared).
From a resolution perspective, it is very unlikely you could observe such a laser beam with a geostationary satellite. If the laser wavelength is suitable and the light scatters enough for the sensor to pick up the light it is possible. (Think shining a laser in a dusty room; you can only see the beam when light deflects off of smoke or other small particles) I would have to look at the numbers on how much lasers scatter at those wavelengths. I think it is unlikely.
Now, with regard to polar satellites; these are satellites that are in a much lower orbit, typically only a few hundred kilometers up. They orbit from pole to pole to pole... etc. in around 90 minutes. (Lower orbits are always faster; if you speed up in a lower orbit, you reach a higher orbit. If you slow down in your orbit, you get into a lower orbit (here's the counterintuitive part), making you orbit faster.
Polar satellites cover the complete surface of the planet eventually, because the planet rotates "beneath" them. In 24 hours you would cover the planet in about 16 equidistant parallel strips. (Imagine taking a beach ball and wrapping a ribbon from top to bottom and back while rotating the beach ball slowly) Depending on the width of these strips, you could theoretically cover the whole beach ball. Typically, however, these strips observed by polar satellites are not very wide, because we want a high imaging resolution. Typical polar satellites cover the entirety of the planet's surface in 3-4 days.
Here we immediately see the trade-off between polar and geostationary satellites: One makes it possible to observe the same location continuously, but at reduced detail. The other allows for much higher detail levels (down to 3-4 inches), but you can not observe all of it at the same time. The solution is of course to have many polar satellites to cover all of the surface within a day or less.
Could you observe a near-infrared/visible laser with a polar satellite? If the satellite is positioned correctly (luck) and the scattering of the laser beam is high enough for the imaging sensor to pick up, then yes. Again, I am not sure if the scattering would be high enough.
However, I know thermal imagers exist that use infrared wavelengths from between 3 to about 600 µm.
I would need to have a look at the source data to find out more. Particularly the directionality of the beam would be of interest. Perhaps, given the time of recording, one could match the beam to a known military satellite.