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Demonstrating ASAT against a GEO target would cause a major political incident. The LEO ASAT tests carried out to date caused enough outcry as is. Hitting a GEO

Demonstrating ASAT against a GEO target would cause a major political incident. The LEO ASAT tests carried out to date caused enough outcry as is. Hitting a GEO target is not difficult. Ignoring dedicated ASAT missiles, any modern IRBM or LRBM can be tasked to intercept a GEO target. Global navigation constellations are certainly going to be one of the first targets in any major hot conflict between world powers. Realistically, a solar storm is a more likely and less predictable threat. The end result is the same, any critical functionality that relies on GPS will be denied for a prolonged period of time.

jessriedel 7y ago
> Hitting a GEO target is not difficult. Ignoring dedicated ASAT missiles, any modern IRBM or LRBM can be tasked to intercept a GEO target. Do you have a cite for this?
- deleted 7y ago
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- missosoup 7y ago
  Not as an overt blanket capability statement, but e.g. LGM-30 is known to carry ASIP and rumoured to carry THAAD kill vehicles, both capable of intercepting dynamic orbital targets. LGM-30 climbs to 100km altitude before deploying the payload bus, which gives it ample range to hit GEO targets anywhere in the hemisphere. Other thing I completely forgot to mention is that all existing global navigation constellations orbit at MEO, not GEO. Which puts them within speculative range of demonstrated ASAT weapons and allows for even longer reach from a launch vehicle like LGM-30. https://www.mda.mil/news/11news0002.html https://www.mda.mil/news/11news0002.html https://www.raytheon.com/capabilities/products/ekv https://www.raytheon.com/capabilities/products/ekv
  - jessriedel 7y ago
    > LGM-30 climbs to 100km altitude before deploying the payload bus, which gives it ample range to hit GEO targets anywhere in the hemisphere. This doesn't make sense to me. Could you explain further? LGM-30 is a land-based ICBM designed to strike targets on the surface of the Earth, and hence to take a (just barely) sub-orbital trajectory <13,000 km from point-to-point, with maximum altitude a few hundred km. Wouldn't its thrust capability have to be drastically upgraded to reach 20,000km in altitude, where MEO satellites like GPS are?
    - missosoup 7y ago
      It takes about 0.6 tons of fuel to transfer from a 100km to a 20,000km orbit. Well within the payload limits of LGM-30. A derivative of the LGM-30, Minotaur, is used to launch satellites (or ordnance) directly to GTO @ ~30,000km.

jessriedel 7y ago

> Hitting a GEO target is not difficult. Ignoring dedicated ASAT missiles, any modern IRBM or LRBM can be tasked to intercept a GEO target. Do you have a cite for this?

deleted 7y ago
[deleted]
missosoup 7y ago
Not as an overt blanket capability statement, but e.g. LGM-30 is known to carry ASIP and rumoured to carry THAAD kill vehicles, both capable of intercepting dynamic orbital targets. LGM-30 climbs to 100km altitude before deploying the payload bus, which gives it ample range to hit GEO targets anywhere in the hemisphere. Other thing I completely forgot to mention is that all existing global navigation constellations orbit at MEO, not GEO. Which puts them within speculative range of demonstrated ASAT weapons and allows for even longer reach from a launch vehicle like LGM-30. https://www.mda.mil/news/11news0002.html https://www.mda.mil/news/11news0002.html https://www.raytheon.com/capabilities/products/ekv https://www.raytheon.com/capabilities/products/ekv
- jessriedel 7y ago
  > LGM-30 climbs to 100km altitude before deploying the payload bus, which gives it ample range to hit GEO targets anywhere in the hemisphere. This doesn't make sense to me. Could you explain further? LGM-30 is a land-based ICBM designed to strike targets on the surface of the Earth, and hence to take a (just barely) sub-orbital trajectory <13,000 km from point-to-point, with maximum altitude a few hundred km. Wouldn't its thrust capability have to be drastically upgraded to reach 20,000km in altitude, where MEO satellites like GPS are?
  - missosoup 7y ago
    It takes about 0.6 tons of fuel to transfer from a 100km to a 20,000km orbit. Well within the payload limits of LGM-30. A derivative of the LGM-30, Minotaur, is used to launch satellites (or ordnance) directly to GTO @ ~30,000km.