The Teslarati article SpaceX’s April 7th Falcon Heavy launch a step toward new commercial markets says:

While there is some inherent uncertainty surrounding the (once again) fairly new rocket, SpaceX has now officially filed a plan with the Cape Canaveral range authorities that would see Falcon Heavy nominally conduct a critical static fire test as soon as March 31st, followed one week later by a launch target of no earlier than (NET) 6:36 pm EDT (22:36 UTC), April 7th. Set to place the ~6000 kg (13,200 lb) Arabsat 6A communications satellite in a high-energy geostationary orbit, a successful mission that ultimately proves Falcon Heavy’s commercial utility could also raise global launch market interest in the rocket, including potential anchor customers like NASA.

  1. What (if anything) is meant by "a high-energy geostationary orbit"?

  2. It SpaceX bringing the satellite all the way to a cis-GEO orbit, or is this a launch only to GTO?

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    $\begingroup$ As you imply, a "high-energy" geostationary orbit isn't really a thing - all true geostationary orbits will have the same energy. I suspect they mean "high energy" in the sense of "higher than low Earth orbits". As to 2. I believe it's going to either a standard GTO or a super-sync orbit, both of which will require the payload to provide some manoeuvring after deployment $\endgroup$ – Jack Mar 21 at 14:27
  • $\begingroup$ @Jack Would "super-sync orbit" be an orbit with higher energy than GEO, or lower? I never know if the "super" means a faster speed or higher semimajor axis. $\endgroup$ – uhoh Mar 21 at 14:28
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    $\begingroup$ A transfer orbit with its apoapsis above geostationary altitude. Wikipedia says that it also refers to an orbit with a larger period than GSO, but I think it more commonly refers to the above described transfer $\endgroup$ – Jack Mar 21 at 14:32
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    $\begingroup$ I would answer, but I'm not certain on the insertion orbit, so I'll leave it for now for someone who knows better places to look for sources! $\endgroup$ – Jack Mar 21 at 14:36
  • $\begingroup$ Have you considered asking the author? $\endgroup$ – Everyday Astronaut Mar 21 at 21:06

The transfer orbit for Arabsat 6a went to an apogee of 90,000km. At that height it's travelling very slowly, so adding delta-V needs less energy. The sat needs both to remove the launch inclination (i.e. 28.5 -> 0) and at the same time raise the perigee to geostationary altitude. Then, when the sat reaches perigee the engine is fired again to circularise the orbit. This needs less energy from the sat's own motor but requires more from the launcher.

  • $\begingroup$ This is a very interesting answer, thank you! Can you cite a source for apogee? Thanks! $\endgroup$ – uhoh Apr 13 at 15:21
  • $\begingroup$ Why does a certain amount of delta-V "need less energy" at low velocity than at high velocity? I thought the velocity influences how much the total kinetic energy is increased by that delta-V (quadratic dependence, Oberth effect). $\endgroup$ – Everyday Astronaut Apr 13 at 16:07
  • $\begingroup$ The name for this type of transfer to geosynchronous orbits is Supersynchronous. As stated, they are useful for combined plane and perigee changes at relatively low fuel expense. $\endgroup$ – Jack Apr 13 at 16:32
  • $\begingroup$ -1 temporarily, as a gentle reminder that it's important to cite your sources when quoting factual information. Right now readers (including me) have no way to know if this answer is wrong or correct. Thanks! $\endgroup$ – uhoh Apr 16 at 3:53

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