NASA's solar sailing spacecraft is tumbling – but that's part of the plan
(2024/09/06)
- Reference: 1725597015
- News link: https://www.theregister.co.uk/2024/09/06/nasa_solar_sail_acs3/
- Source link:
NASA has announced its experimental ACS3 solar-sailing spacecraft is working as expected, after it was spotted tumbling in the night sky.
The 80 m 2 (860 sq ft) Advanced Composite Solar Sail System (ACS3) successfully [1]spread its sails last week. The spacecraft uses [2]pressure produced by solar radiation to move – doing away with conventional rocket propellant. NASA is testing the sail in the hope that its design, and the materials used, are viable for future vessels.
As the boffins put it:
NASA's Advanced Composite Solar Sail System, or ACS3, technology demonstration uses composite materials – or a combination of materials with different properties – in its novel, lightweight booms that deploy from a CubeSat. Data obtained from ACS3 will guide the design of future larger-scale composite solar sail systems that could be used for space weather early warning satellites, near-Earth asteroid reconnaissance missions, or communications relays for crewed exploration missions.
Questions were raised this week after the instrument – which launched in April and is now in Earth's orbit – was [3]observed to be slowly tumbling, gyrating, or wobbling.
NASA's Langley Research Center assured the public that's neither unusual nor worrying.
[4]
"Our Solar Sail System is sailing around Earth, slowly tumbling as expected while the mission team characterizes its boom and sails," the agency [5]explained Thursday.
[6]
[7]
You can, we're told, track the craft from NASA's [8]app .
[9]
Engineers at NASA's Langley Research Center work on an unfurled Advanced Composite Solar Sail System's solar sail – Click to enlarge. Source: [10]NASA
The first probe to use solar radiation pressure as a major means for orientation during flight was NASA's 1970s-era [11]Mariner 10 , which caught sunlight on its solar panels and high-gain antenna. ACS3 is using vastly larger composite sails to do this – and hopefully far more efficiently.
[12]Bill Nye's bonkers LightSail spaceship unfurls solar sails at last
[13]I've seen things you people wouldn't believe. Spacecraft with graphene sails powered by starlight and lasers
[14]To infinity and beyond, with a swarm of tiny computers costing under $1K each
NASA is not alone in pursuing solar sails. Japan's JAXA [15]managed a Venus flyby in 2010 using solar sails. And the Planetary Society [16]executed an unfurling in 2019.
It's not ACS3's sails that are of most interest: the booms on which they hang are said to be "made from a polymer material that is flexible and reinforced with carbon fiber."
"This composite material can be rolled for compact stowage, but remains strong and lightweight when unrolled. It is also very stiff and resistant to bending and warping due to changes in temperature," according to NASA.
[17]
"The ACS3 technology demonstration will also test an innovative tape-spool boom extraction system designed to minimize jamming of the coiled booms during deployment."
Coiled components matter, because they mean items with large surface area can be packed into the small volume of spacecraft, making them easier to launch. ®
Get our [18]Tech Resources
[1] https://www.theregister.com/2024/09/04/nasa_acs3_solar_sail/
[2] https://www.nasa.gov/smallspacecraft/what-is-acs3/
[3] https://sattrackcam.blogspot.com/2024/09/acs-3-appears-to-be-tumbling.html?
[4] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_offbeat/science&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=2&c=2ZtrSyOsilpP9azlCbOfQtgAAAUE&t=ct%3Dns%26unitnum%3D2%26raptor%3Dcondor%26pos%3Dtop%26test%3D0
[5] https://x.com/NASA_Langley/status/1831795029939011811
[6] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_offbeat/science&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=4&c=44ZtrSyOsilpP9azlCbOfQtgAAAUE&t=ct%3Dns%26unitnum%3D4%26raptor%3Dfalcon%26pos%3Dmid%26test%3D0
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[8] https://www.nasa.gov/nasa-app/
[9] https://regmedia.co.uk/2024/09/06/nasa_acs3_factory.jpg
[10] https://www.nasa.gov/mission/acs3/
[11] https://science.nasa.gov/mission/mariner-10/
[12] https://www.theregister.com/2015/06/08/stars_ahoy_crowdfunded_lightsail_spacecraft_successfully_deploys_solar_sails/
[13] https://www.theregister.com/2020/05/09/lightsails_graphene/
[14] https://www.theregister.com/2023/07/26/linux_in_space/
[15] https://www.theregister.com/2024/09/04/nasa_acs3_solar_sail/
[16] https://www.theregister.com/2019/07/24/lightsail_2_unfurls_sails/
[17] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_offbeat/science&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=4&c=44ZtrSyOsilpP9azlCbOfQtgAAAUE&t=ct%3Dns%26unitnum%3D4%26raptor%3Dfalcon%26pos%3Dmid%26test%3D0
[18] https://whitepapers.theregister.com/
The 80 m 2 (860 sq ft) Advanced Composite Solar Sail System (ACS3) successfully [1]spread its sails last week. The spacecraft uses [2]pressure produced by solar radiation to move – doing away with conventional rocket propellant. NASA is testing the sail in the hope that its design, and the materials used, are viable for future vessels.
As the boffins put it:
NASA's Advanced Composite Solar Sail System, or ACS3, technology demonstration uses composite materials – or a combination of materials with different properties – in its novel, lightweight booms that deploy from a CubeSat. Data obtained from ACS3 will guide the design of future larger-scale composite solar sail systems that could be used for space weather early warning satellites, near-Earth asteroid reconnaissance missions, or communications relays for crewed exploration missions.
Questions were raised this week after the instrument – which launched in April and is now in Earth's orbit – was [3]observed to be slowly tumbling, gyrating, or wobbling.
NASA's Langley Research Center assured the public that's neither unusual nor worrying.
[4]
"Our Solar Sail System is sailing around Earth, slowly tumbling as expected while the mission team characterizes its boom and sails," the agency [5]explained Thursday.
[6]
[7]
You can, we're told, track the craft from NASA's [8]app .
[9]
Engineers at NASA's Langley Research Center work on an unfurled Advanced Composite Solar Sail System's solar sail – Click to enlarge. Source: [10]NASA
The first probe to use solar radiation pressure as a major means for orientation during flight was NASA's 1970s-era [11]Mariner 10 , which caught sunlight on its solar panels and high-gain antenna. ACS3 is using vastly larger composite sails to do this – and hopefully far more efficiently.
[12]Bill Nye's bonkers LightSail spaceship unfurls solar sails at last
[13]I've seen things you people wouldn't believe. Spacecraft with graphene sails powered by starlight and lasers
[14]To infinity and beyond, with a swarm of tiny computers costing under $1K each
NASA is not alone in pursuing solar sails. Japan's JAXA [15]managed a Venus flyby in 2010 using solar sails. And the Planetary Society [16]executed an unfurling in 2019.
It's not ACS3's sails that are of most interest: the booms on which they hang are said to be "made from a polymer material that is flexible and reinforced with carbon fiber."
"This composite material can be rolled for compact stowage, but remains strong and lightweight when unrolled. It is also very stiff and resistant to bending and warping due to changes in temperature," according to NASA.
[17]
"The ACS3 technology demonstration will also test an innovative tape-spool boom extraction system designed to minimize jamming of the coiled booms during deployment."
Coiled components matter, because they mean items with large surface area can be packed into the small volume of spacecraft, making them easier to launch. ®
Get our [18]Tech Resources
[1] https://www.theregister.com/2024/09/04/nasa_acs3_solar_sail/
[2] https://www.nasa.gov/smallspacecraft/what-is-acs3/
[3] https://sattrackcam.blogspot.com/2024/09/acs-3-appears-to-be-tumbling.html?
[4] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_offbeat/science&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=2&c=2ZtrSyOsilpP9azlCbOfQtgAAAUE&t=ct%3Dns%26unitnum%3D2%26raptor%3Dcondor%26pos%3Dtop%26test%3D0
[5] https://x.com/NASA_Langley/status/1831795029939011811
[6] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_offbeat/science&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=4&c=44ZtrSyOsilpP9azlCbOfQtgAAAUE&t=ct%3Dns%26unitnum%3D4%26raptor%3Dfalcon%26pos%3Dmid%26test%3D0
[7] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_offbeat/science&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=3&c=33ZtrSyOsilpP9azlCbOfQtgAAAUE&t=ct%3Dns%26unitnum%3D3%26raptor%3Deagle%26pos%3Dmid%26test%3D0
[8] https://www.nasa.gov/nasa-app/
[9] https://regmedia.co.uk/2024/09/06/nasa_acs3_factory.jpg
[10] https://www.nasa.gov/mission/acs3/
[11] https://science.nasa.gov/mission/mariner-10/
[12] https://www.theregister.com/2015/06/08/stars_ahoy_crowdfunded_lightsail_spacecraft_successfully_deploys_solar_sails/
[13] https://www.theregister.com/2020/05/09/lightsails_graphene/
[14] https://www.theregister.com/2023/07/26/linux_in_space/
[15] https://www.theregister.com/2024/09/04/nasa_acs3_solar_sail/
[16] https://www.theregister.com/2019/07/24/lightsail_2_unfurls_sails/
[17] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_offbeat/science&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=4&c=44ZtrSyOsilpP9azlCbOfQtgAAAUE&t=ct%3Dns%26unitnum%3D4%26raptor%3Dfalcon%26pos%3Dmid%26test%3D0
[18] https://whitepapers.theregister.com/
Re: How do you steer such a craft?
Anonymous Coward
Everything is in orbit*. If you're orbiting the sun, you decrease your speed to lower the orbit toward the sun. As you mention angling the sail can do this. Angling the other way increases the speed and therefore raises the orbit.
* Sometimes the periapsis (lowest point of the orbit) is inside the object you're orbiting so you won't orbit for long.
Re: How do you steer such a craft?
Richard 12
You can always use an etheric keel and rudder.
More seriously, to go closer to the Sun you need to slow down the orbit, thrusting along your direction of travel.
In a circular orbit that is exactly perpendicular to the radius. In a highly elliptical orbit that vector can be a little towards or away from the radius, although unless the ellipse is extreme, it's basically perpendicular.
Thrusting radially does not (alone) raise or lower your orbit, it only adjusts the elements by a small amount, as it's by far the least efficient direction.
Of course, if you adjust the elements to interact closely with something else, then that will significantly change the orbit as momentum is exchanged.
Anonymous Coward
We've been hearing about solar sails for decades. Great to see one finally up there being tried out.
How do you steer such a craft?
Given that the light pressure is always radial to the sun, I suppose that by tilting the sail you can change the angle of reflection and thus the thrust? But you can only ever go outwards?
And unlike a sailing boat, you can't tack close to the wind (or in this case, the sun)? I guess there's no Coanda effect to generate lift.