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Space based works for optical, but not all other wave length. For example it will also reduce the sensitivity of air cherenkov telescopes that detect gamma rays

Space based works for optical, but not all other wave length. For example it will also reduce the sensitivity of air cherenkov telescopes that detect gamma rays and that can not be moved to space.

xur17 7y ago
Why can't those be moved to space?
- rtkwe 7y ago
  They are imaging the flashes as the relativistic particles slam into our atmosphere. No atmosphere, no flash. https://en.wikipedia.org/wiki/IACT https://en.wikipedia.org/wiki/IACT
- HorstG 7y ago
  Because cherenkov radiation is only observable in a transparent medium like air or water. Space doesn't work because the speed of light in space equals the speed of light in vacuum, therefore no cherenkov radiation.
  - Taniwha 7y ago
    Couldn't they look down?
    - HorstG 7y ago
      Cherenkov telescopes for neutrinos do look down for reasons of schielding. Neutrinos can pass the earth, other particles not so much. But those are a special case, air cherenkov telescopes are looking for "less weird" particles like photons or protons. Those can only be seen looking up, since the primary particles moving down focuses the cherenkov light down in a narrow cone.
    - petschge 7y ago
      The Cherenkov emission is boosted in the direction of travel, i.e. downward. And there are too many lights on the surface of the Earth.
  - m4rtink 7y ago
    While this certainly requires non trivial large scale space engineering, you should be able to build in in principle. Basically a big bubble filled with the most useful gas for this + bunch of photodetectors inside at the appropriate places. You could also make the whole detection chamber much larger, than the ~30 km (?) of reasonably thick atmosphere you get on Earth.
- deleted 7y ago
  [deleted]
Ajedi32 7y ago
Would air cherenkov telescopes be significantly affected by additional satellites in orbit? It sounds like they're designed to detect high energy gamma rays striking the atmosphere, so probably not?
- SiempreViernes 7y ago
  In practice they are looking for very weak flashes of light, adding extra background light obviously reduced sensitivity.
dnautics 7y ago
is cherenkov radiation even observable during dawn/dusk +/- 2 hours? I imagine that the atmospheric refraction of the sun would seriously hamper those observations during that time period.
- petschge 7y ago
  On traditional telescope using photomultipliers such as Magic, Hess or Veritas: no. But systems with solid state detectors such as FACT are moving in that direction.
  - dnautics 7y ago
    Can you explain that for me? I'm not sure how better detectors let you delete the noise from the sun.
nwallin 7y ago
I'm struggling to see how starlink will affect those telescopes. Please explain?

Space based works for optical, but not all other wave length. For example it will also reduce the sensitivity of air cherenkov telescopes that detect gamma rays and that can not be moved to space.

xur17 7y ago

Why can't those be moved to space?

rtkwe 7y ago
They are imaging the flashes as the relativistic particles slam into our atmosphere. No atmosphere, no flash. https://en.wikipedia.org/wiki/IACT https://en.wikipedia.org/wiki/IACT
HorstG 7y ago
Because cherenkov radiation is only observable in a transparent medium like air or water. Space doesn't work because the speed of light in space equals the speed of light in vacuum, therefore no cherenkov radiation.
- Taniwha 7y ago
  Couldn't they look down?
  - HorstG 7y ago
    Cherenkov telescopes for neutrinos do look down for reasons of schielding. Neutrinos can pass the earth, other particles not so much. But those are a special case, air cherenkov telescopes are looking for "less weird" particles like photons or protons. Those can only be seen looking up, since the primary particles moving down focuses the cherenkov light down in a narrow cone.
  - petschge 7y ago
    The Cherenkov emission is boosted in the direction of travel, i.e. downward. And there are too many lights on the surface of the Earth.
- m4rtink 7y ago
  While this certainly requires non trivial large scale space engineering, you should be able to build in in principle. Basically a big bubble filled with the most useful gas for this + bunch of photodetectors inside at the appropriate places. You could also make the whole detection chamber much larger, than the ~30 km (?) of reasonably thick atmosphere you get on Earth.
deleted 7y ago
[deleted]

Ajedi32 7y ago

Would air cherenkov telescopes be significantly affected by additional satellites in orbit? It sounds like they're designed to detect high energy gamma rays striking the atmosphere, so probably not?

SiempreViernes 7y ago
In practice they are looking for very weak flashes of light, adding extra background light obviously reduced sensitivity.

dnautics 7y ago

is cherenkov radiation even observable during dawn/dusk +/- 2 hours? I imagine that the atmospheric refraction of the sun would seriously hamper those observations during that time period.

petschge 7y ago
On traditional telescope using photomultipliers such as Magic, Hess or Veritas: no. But systems with solid state detectors such as FACT are moving in that direction.
- dnautics 7y ago
  Can you explain that for me? I'm not sure how better detectors let you delete the noise from the sun.

nwallin 7y ago

I'm struggling to see how starlink will affect those telescopes. Please explain?