SpaceBreak—Rocket Lab to Unfurl NASA's Solar Sail
Welcome to your SpaceBreak for April 15th, 2024.
Breaking in Space:
Rocket Lab Tacking into the (Solar) Wind
(Been away for a little bit, back now.)
From Space.com: Rocket Lab will be carrying NASA’s Advanced Composite Solar Sail System (ACS3) into orbit “no sooner than April 24”.
Solar sails are a bit like terrestrial sails, except that they’re catching moving light instead of air. While the amount of acceleration that you get from the sail is minuscule, a big enough sail could slowly but steadily accelerate a spacecraft over a long period of time, without any need for propellants. Several experiments have been made regarding solar sails, most notably the Planetary Society’s LightSail 2.
(Ion drives are somewhat similar that way; the delta v that they provide is small, but very steady, and over enough time can get a spacecraft moving at a pretty good clip without requiring much in the way of heavy and massive propellant.)
In order to be effective, though, a solar sail has to be enormous. So this particular mission is primarily to test composite booms made of carbon fiber reinforced polymer (CFRP) which are “meant to unfurl and hold four very thin triangular sheets tautly”, transforming a microwave-sized payload into a kite-shaped multi-part sail the size of a small apartment. LightSail 2 used rigid metal booms; this could be thought of as the next step in solar sail development.
NASA’s lead systems engineer on the project, Alan Rhodes, said that “seven meters of the deployable booms can roll up into a shape that fits in your hand”. With that in mind, think about how much could fit in a heavy-lift launcher like a Starship or New Glenn. You could get absolutely gargantuan solar sails, which would still involve a lot less mass than the propellant you’d need for a traditional engine.
Once the ACS3 mission gets up to its orbit, 1000km above the surface, the spacecraft will “begin the 25-minute process of unrolling the composite booms, which span the diagonals of the sail.” And, if all goes well, the mission will also test changing the spacecraft’s orbit using adjustments of the sail.
Will we get to witness NASA engineers shouting “TRIM THE SOLAR SAILS”, Possibly while wearing a fancy officer’s hat? One can only hope.
Other Breaking Headlines:
Superfast drone fitted with new 'rotating detonation rocket engine' approaches the speed of sound (Space.com)
Space Force eyes faster satellite development with commercial tech (SpaceNews)
Space Force acquisition command prioritizing speed and commercial partnerships (SpaceNews)
A “slow bleed” of funding threatens NASA’s science flagships (SpaceNews)
China launches commercial SuperView-3 remote sensing sat (SpaceNews)
ESA accelerates the race towards clean energy from space (ESA)
Astrobotic Exploring National Security Tech Crossover (Payload)
SpaceX to launch Maxar WorldView Legion 1 & 2 mission for leading resolution and accuracy (SatNews)
A Cool Space Picture:
Finally, here’s a great pic of a Dragon Arc from the James Webb feed on Bluesky:
Dragon arc: a single strongly-lensed high-redshift galaxy behind the Abell 370 cluster at redshift of 0.725 when the Universe was half of its current age…A research group identified 46 microlensed stars in it.