Radio-wave Observations at the Lunar Surface of the photoElectron Sheath (ROLSES)¶
Blue Ghost Mission 3 · manifested · NASA payload
ROLSES 2, an improved copy of the low-frequency radio receiver that flew on Intuitive Machines' IM-1 in 2024. Four antennas, now set up as a crossed dipole 1 to 2 m above the ground, feed a spectrometer (about 10 kHz to 30 MHz or more). It measures the density of the thin photoelectron layer above the surface and the radio noise near the Moon, natural and human-made. New in ROLSES 2: onboard calibration, phase data between antennas, and fixes for the flaws found on IM-1.
PI: Natchimuthuk (Nat) Gopalswamy, NASA Goddard
Built by: NASA Goddard Space Flight Center; STACER antennas by Heliospace Corporation; science co-investigator at the University of Colorado Boulder (NASA center)
| Technology | science instrument (radio and plasma environment) |
| Moon Base need | DN-011 L, #0103 (Partly NASA's link. NASA's CP-21 page says ROLSES will show how natural and human-made activity could affect science and habitation on the surface. The ties by ID are the study's reading, as for ROLSES on IM-1: the surface plasma (DN-011 L) and the radio environment that surface radios must work in (#0103). DN-011 L is written for the South Pole; Gruithuisen is a northern near-side site.) |
| Route onto CLPS | NPLP; NASA-Provided Lunar Payloads, 21 February 2019, as 'Low-frequency Radio Observations from the Near Side Lunar Surface'. The first unit flew on IM-1 (TO2-IM). NASA re-manifested the investigation, under the same NPLP name, on Firefly's CP-21 (18 December 2024).; 2019-02-21 |
| Timeline | first funding 2019 (NPLP selection); earliest public award: Heliospace ROLSES 1 antenna order, 2020; ROLSES 2 antenna order 2025-01-13; first flight test 2024-02-15 (ROLSES 1 on IM-1, in transit and on the surface); selected 2019-02-21; task order CP-21 to Firefly 2024-12-18; launch Not yet launched. The paper says launch in 2028; NASA targets landing in 2028.; landing not in public sources |
| On the Moon | not yet flown |
| FO | none |
Flights before the Moon¶
- earlier lunar mission: Intuitive Machines IM-1 (Odysseus), CLPS task order TO2-IM: ROLSES 1, 2024-02-15 launch; 2024-02-22 landing. The first version of the same instrument. In transit, sunlight overheated one antenna's release bolt and that antenna deployed early and was damaged; ROLSES still recorded Earth's radio transmitters about 9,600 km from the Moon. After the tipped landing a second antenna deployed on its own; the team deployed the other two by command. Only 36 minutes of surface spectra came back, against 170 to 340 hours planned, with the gain stuck at its lowest. The team also found a data-discarding error in the DSP. ROLSES 2 fixes these and adds calibration and phase data.
"Intuitive Machines's Nova-C lunar lander launched on February 15, 2024 to deliver 6 NASA CLPS science payloads to Malapert A. It landed on February 22, 2024."
— Commercial Lunar Payload Services (CLPS) Deliveries - NASA Science"in the inadvertent deployment and damage of the antenna when the lander was about 9600 km from the Moon"
— arxiv.org: 2603.22600, section 1"only 36 minutes of spectral data was obtained compared to the projected 170 to 340 hours of data"
— arxiv.org: 2603.22600"fix the data-discarding error from the flown version"
— arxiv.org: 2603.22600, section 7
Heritage hardware¶
- flown predecessor (same instrument line): ROLSES 2 keeps most of ROLSES 1's signal chain. Changes: onboard calibration from a signal generated in the FPGA; a DSP that gives phase data between antennas (for Stokes parameters), meets FPGA timing (sampling cut from 120 to 80 MHz) and no longer discards data; bands widened to 40 MHz and 2.5 MHz; 16-bit floating-point output, doubling the science rate; antennas set as a crossed dipole; flight-like test antennas for pre-flight testing (ROLSES 1 had none); thermal blankets against early antenna deployment.
"There are two primary additions to ROLSES 2: introduction of onboard calibration and modification of the DSP to obtain Stokes parameters."
— arxiv.org: 2603.22600, section 7"Unlike ROLSES 1, test antennas very similar to flight antennas were procured for ROLSES 2.0 for pre-flight testing."
— arxiv.org: 2603.22600, section 7"care has been taken to mitigate the inadvertent antenna deployment issues by using appropriate thermal blankets"
— arxiv.org: 2603.22600, section 7
- design heritage (antennas): Beryllium-copper STACER monopoles like the STEREO/WAVES antennas, but smaller (from the IM-1 record).
"made of beryllium copper (Be-Cu) alloy, similar to STEREO/WAVES antennas"
— arxiv.org: 2603.22600, section 3.1
Funding before the lunar flight¶
- SMD NASA-Provided Lunar Payloads, supported through NASA's CLPS program (as for ROLSES 1). No total in public sources. (SMD NPLP / CLPS; from 2019): amount not in public sources
"This NPLP is supported by NASA's CLPS program and we thank them for their support throughout ROLSES development."
— arxiv.org: 2603.22600, Acknowledgments
- Purchase order 80NSSC25PA409 to Heliospace Corporation for the ROLSES 2.0 proto-flight antennas. Linked by its description. (NASA purchase order (NASA Shared Services Center); 2025-01-13 to 2026-01-09): $155,000
"ROLSES 2.0 PFM ANTENNA"
— USAspending.gov, 80NSSC25PA409, amount 155000.0
- ROLSES 1 flight antennas: purchase order 80NSSC20P1770 to Heliospace Corporation, for the predecessor that flew on IM-1. Linked by its description ('ROLES' as printed). (NASA purchase order; 2020-2021): $172,010
"PROVIDE ROLES PFM ANTENNA DEVELOPMENT AND PRODUCTION/STACER FLIGHT ANTENNAS"
— USAspending.gov, 80NSSC20P1770, amount 172010.46 (as printed)
- ROLSES 1 antenna simulator: purchase order 80NSSC20P1831 to Heliospace Corporation. Linked by its description. (NASA purchase order; 2020): $32,442
"ROLSES ANTENNA SIMULATOR"
— USAspending.gov, 80NSSC20P1831, amount 32441.65
- Grant 80NSSC22K1264 to the University of Colorado for the co-investigator's science work on the investigation (title uses the NPLP name). It funded ROLSES-1 data analysis and runs to 2028; whether it also covers ROLSES 2 is not stated. Science support, not hardware. (NASA grant (SMD ESSIO); 2022-06-15 to 2028-04-30): $855,652
"LOW FREQUENCY RADIO OBSERVATIONS FROM THE NEAR SIDE LUNAR SURFACE (I.E ROLSES INSTRUMENT)"
— USAspending.gov, 80NSSC22K1264, amount 855652.0"funded by NASA grant 80NSSC22K1264 from the Exploration Science Strategy Integration Office (ESSIO)"
— arxiv.org: 2503.09842, Acknowledgments
How it got onto CLPS¶
"The Low-frequency Radio Observations from the Near Side Lunar Surface instrument, a radio science instrument, will measure the photoelectron sheath density near the surface."
— NASA Selects Experiments for Possible Lunar Flights in 2019 - NASA, release of 21 Feb 2019"is designed to observe the Moon’s surface environment in radio frequencies, to determine whether natural and human-generated activity near the surface interferes with science"
— More NASA Science, Tech will Fly to Moon Aboard Future Firefly Flight - NASA, release of 18 Dec 2024"ROLSES is one of the NASA Provided Lunar Payloads (NPLPs) selected under the CLPS program."
— arxiv.org: 2603.22600, section 1
On the Moon¶
ROLSES 2 is to complete the science ROLSES 1 could not, from the Gruithuisen Domes in 2028.
"An upgraded ROLSES-2 is scheduled to go to the Moon in 2028 to complete the original science objectives for ROLSES."
— arxiv.org: 2603.22600
FO's role¶
Grade: none. No FO project, flight or report names ROLSES, its Goddard team or Heliospace; the study searched the 430 FO TechPort records, FO's reports and FO's pages. ROLSES's flight test before Blue Ghost 3 was its own first lunar flight, on IM-1. FO once flew a STACER antenna deployment test in microgravity for an MIT CubeSat (TechPort 12257, 2013-2016): same antenna type, different team, topic only. ROLSES 1's early deployment came from sunlight heating a release bolt, not from gravity. The study's earlier traceback grade (none found) stands.
"Surface of the photoElectron Sheath (ROLSES) radio telescope"
— earlier finding of this study (not a public source)"A microgravity environment on a parabolic flight would enable testing of the deployment mechanism and antenna dynamics"
— TechPort project 12257, description (MIT TERSat STACER test; not ROLSES)
Who built it¶
"PI: Natchimuthuk “Nat” Gopalswamy, Goddard Space Flight Center"
— CLPS CP-21 Science - NASA Science"ROLSES 2.0 PFM ANTENNA"
— USAspending.gov, 80NSSC25PA409, Heliospace Corporation, 155000.0, 2025-01-13 to 2026-01-09"antennas designed and built by Heliospace Inc."
— arxiv.org: 2603.22600, section 3.1, (ROLSES 1)
Moon Base need¶
"It’s important for us to understand how organic and human-made activity could affect science and habitation on the lunar surface."
— CLPS CP-21 Science - NASA Science"Measure the plasma environment at the lunar south pole"
— Moon to Mars knowledge base: DN-011 L: In situ lunar surface plasma environment characterization, Description"Deploy communications systems that can operate in the lunar geological, electromagnetic, and radio frequency environment."
— Moon to Mars knowledge base: Moon Base technology and knowledge challenges, Associated challenges, Surface-to-surface comms
Open questions¶
- Total cost of ROLSES 2 under NPLP: not in public sources; only the antenna order (USD 155,000) is public.
- Was any ROLSES 2 part flight-tested before the Moon (for example an antenna deployment test)? Not in public sources; the team procured flight-like test antennas for ground tests.
- Does grant 80NSSC22K1264 cover ROLSES 2 science, or only ROLSES 1 analysis? Not stated.