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Robot Gas Attendants Could Keep Old Satellites Chugging

Robot gas attendants could keep old satellites chugging.

MDA has a contract, and a good design. If they succeed in refueling an old communications satellite with a robot, it will be fundamentally change the launch industry. If satellites don’t have to be replaced as often, there will less need for launches, reducing the demand for rockets.

Genesis cover

On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.

The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.

The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.

"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News


  • BSJ

    But you still have to launch the robot. And if you have to go through all the trouble of launcing something, a newer and or better satellite may be the better option.

    Also, unless the robot has a REALLY HUGE fule supply of it’s own, you’d need to launch one robot per refuel mission.

  • mike shupp

    No, suppose you boost a 30-40 ton tanker with say 25 tons of hydrazine — that ought to be a stock Falcon 9 or Atlas mission. The tanker drifts about earth a bit above or below a geostationary orbit, rendezvousing with several comsats which it supplies with say 200 gallons of fuel. That should keep the comsats going another 5-10 years, and keep the tanker manuevering for maybe just as long.

    The question is, does it make sense to prolong the life of comsats in this fashion? Yes, it’s undoubtably cheaper to keep a 2 billion dollar satellite going for fifteen years rather than say ten. OTOH, a 10-15 year old comsat is probably pretty damned obsolescent; it might just be better to accept the 2-3 billion cost of replacement if a new satellite has sufficient capacity

  • Joe2

    My understanding is that even the notional (but not yet existent) Falcon Heavy would only place 53 tons into LEO (and that would require the – interesting – cross feed capability) the Falcon Heavy delivery to GEO would have to be considerably less (and the capacities of the Falcon 9 and Atlas 5 are already considerably less than the claimed capability of the Falcon Heavy).

    Additionally the rendezvous/docking capabilities would require mass for engines, tankage and fuel.

    So the idea that either the Falcon 9, the Atlas 5 or even the Falcon Heavy is going to deliver a total of 25 tons of propellant to several different GEO satellites is problematic at best.

  • mike shupp

    I’m stealing from Wikipedia:

    “Falcon Heavy, previously known as the Falcon 9 Heavy, is a spaceflight launch system that uses rocket engines currently being designed and manufactured by SpaceX. Multiple variants are planned with payloads of 53,000 kilograms (120,000 lb) to low Earth orbit, 19,000 kilograms (42,000 lb) to geostationary transfer orbit, 16,000 kilograms (35,000 lb) to translunar trajectory, and 14,000 kilograms (31,000 lb) towards Mars…. ”

    So, not 25 tons of fuel at Geosynchrous Earth Orbit, only 21 tons, using a Falcon Heavy rather than a Falcon 9.

    I should cut my throat with chagrin for this inaccuracy?

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