Near-Earth Asteroid Scout Explained

Near-Earth Asteroid Scout
Names List:NEA Scout
Mission Type:Technology demonstrator, Reconnaissance
Operator:NASA
Cospar Id:2022-156H
Satcat:57684
Mission Duration:2.5 years (planned)
(final)
Spacecraft Type:CubeSat
Spacecraft Bus:6U CubeSat
Dimensions:
Solar sail:
Launch Date:16 November 2022, 06:47:44 UTC[1]
Launch Rocket:SLS Block 1
Launch Site:KSC, LC-39B[2]
Launch Contractor:NASA
Last Contact:Never established
Apsis:helion
Trans Twta:2 watts
Insignia:NEA Scout Logo.png
Insignia Caption:NEA Scout Mission Patch
Insignia Size:200px

The Near-Earth Asteroid Scout (NEA Scout) was a mission by NASA to develop a controllable low-cost CubeSat solar sail spacecraft capable of encountering near-Earth asteroids (NEA).[3] [4] NEA Scout was one of ten CubeSats launched into a heliocentric orbit on Artemis 1, the maiden flight of the Space Launch System, on 16 November 2022.[1] [5]

The target for the mission was asteroid 2020 GE,[6] but this could have changed based on launch date or other factors.[7] After deployment, NEA Scout was to perform a series of lunar flybys to achieve optimum departure trajectory before beginning its two-year-long cruise.

No contact with the spacecraft was ever made, and the mission was lost.[8]

Overview

The mission was funded by NASA's Human Exploration and Operations Mission Directorate. Near-Earth asteroids (NEAs) are of interest to science, and as NASA continues to refine its plans to possibly explore these small objects with human explorers, initial reconnaissance with inexpensive robotic precursors is necessary to minimize risks, and inform the required instruments for future reconnaissance missions. The characterization of NEAs that are larger than in diameter is also of great relevance to plan mitigation strategies for planetary defense.[4]

NASA's Marshall Space Flight Center (MSFC) and Jet Propulsion Laboratory (JPL) jointly developed this mission with support from NASA's Goddard Space Flight Center (GSFC), Lyndon B. Johnson Space Center (JSC), Langley Research Center (LRC), and NASA Headquarters. The principal investigator (science) was Julie Castillo-Rogez from NASA's JPL. The principal investigator was Les Johnson from NASA MSFC.

Goal

The NASA Near Earth Asteroid (NEA) Scout mission was going to demonstrate the capability of an extremely small spacecraft, propelled by a solar sail, to perform reconnaissance of an asteroid at low cost. The goal was to develop a capability that would close knowledge gaps at a near-Earth asteroid in the 1–100 m range.[4] [9] NEAs in the 1–100 m range are poorly characterized due to the challenges that come with detecting, observing, and tracking these for extended periods of time. It has been thought that objects in the 1–100 m size range are fragments of bigger objects. However, it has also been suggested that these objects could actually be rubble piles.[4]

The mission researchers argued that "characterization of NEAs that are larger than 20 m in diameter is also of great relevance to inform mitigation strategies for planetary defense".

Target

The planned target was near-Earth asteroid 2020 GE. The asteroid made a close approach to Earth in September 2023 of around 5.7 million kilometres, which was when NEA Scout was scheduled to make its flyby. The spacecraft would have approached the asteroid at less than a mile distant, and make the slowest flyby of any asteroid by any spacecraft at less than 30 m/s. A 14 megapixel camera, the mission's sole instrument, was going to image the object at very high resolutions of up to 10 cm/pixel.

2020 GE is no more than 18 meters across, and would have been the smallest object yet explored by spacecraft.

Status

As of 17 November 2022, NEA Scout was one of two out of the ten cubesats released by Artemis I whose status remained unknown.[10] Communications with the spacecraft had not been established as of 18 November 2022, two days after launch.[11]

As of December 2022, NEA Scout was considered lost, after deployment of its solar sail had failed and contact could not be established.[8]

Payload

Observations would have been achieved using a CubeSat performing a close (~10 km) flyby, equipped with a high resolution science-grade monochromatic camera to measure the physical properties of a near-Earth object. The camera was a custom JPL design.[12] The electronics were based on the context camera design for the Orbiting Carbon Observatory 3 (OCO3) instrument[13] with a custom firmware, a ruggedized commercial lens and a fully re-designed enclosure.[12] The measurements to be addressed included target's accurate positioning (position and prediction), rotation rate and pole position, mass, density, mapping of particles and debris field in target vicinity, albedo and asteroid spectral type, surface morphologies and properties, and regolith properties.[4] The mission used NASA's Deep Space Network as the primary component for communications and tracking.[4]

Design

The spacecraft architecture, first presented in 2014, was based on a 6-unit CubeSat with a stowed envelope slightly larger than 10 × 20 × 30 cm, a mass of, cold gas thruster system,[14] and was primarily based on the use of commercial off-the-shelf parts.[4] While it is possible for a 6U CubeSat to reach an NEA with conventional chemical propulsion, both the number of targets and the launch window would be tightly constrained. By utilizing solar sail propulsion, intercepting a large number of targets in any launch window is made possible.[15] The mission duration was estimated at 2.5 years.[16]

After deployment in cislunar space, NEA Scout was intended to deploy its solar panels and antenna. Following a lunar flyby, the solar sail would have deployed and spacecraft checkout would have begun. NEA Scout would then have performed a series of lunar flybys to achieve optimum departure trajectory before beginning its 2.0 – 2.5 year-long cruise to the asteroid 2020 GE.[17]

SailFour 6.8 m booms were designed to deploy the single 85 m2 aluminized polyimide solar sail, which is 2.5 μm thick. The sail deployment mechanism was a modification of those of NanoSail and The Planetary Society's LightSail 2 spacecraft.[15] [17] The deployment time for the full sail was planned to be approximately 30 minutes.
AvionicsThe avionics module accommodated the printed circuit boards for telecommunications, power distribution unit, command and data handling system, Sun sensors, and a miniaturized star tracker. This module also included reaction wheels, lithium batteries, and a camera.[4] The solar sail spacecraft attitude control system consisted of three actuating subsystems: a reaction wheel control system, a reaction control system, and an adjustable mass translator system.[18]
PropulsionThe cold gas propulsion system was situated below the solar sail and provides detumbling, initial impulsive maneuvers (required for lunar-assisted escape trajectories), and momentum management.[14]
CommunicationsThe spacecraft used the Iris transponder for communications in the X-band.[4]
PowerPhotovoltaic solar panels, with rechargeable batteries.

See also

Solar sail spacecraft
Other deep space CubeSats
The 10 CubeSats flying in the Artemis 1 mission

Notes and References

  1. News: Roulette . Joey . Gorman . Steve . 2022-11-16 . NASA's next-generation Artemis mission heads to moon on debut test flight . en . Reuters . 2022-11-16.
  2. Web site: NASA Advisory Council - Exploration Systems Development Status. Hill. Bill. NASA. 7 March 2012. 11 March 2021. 31 August 2020. https://web.archive.org/web/20200831121611/https://www.nasa.gov/pdf/630149main_5-Hill_SLS%20MPCV%20GSDO_508.pdf. dead.
  3. Web site: NASA TechPort – Near Earth Asteroid Scout (NEA Scout). NASA TechPort. NASA. 2015. 11 March 2021. 29 November 2020. https://web.archive.org/web/20201129163220/https://techport.nasa.gov/view/14656. dead.
  4. Web site: Near-Earth Asteroid Scout. McNutt. Leslie . Castillo-Rogez. Julie. NASA. American Institute of Aeronautics and Astronautics (AIAA). 4 August 2014. 11 March 2021.
  5. Web site: Clark . Stephen . Adapter structure with 10 CubeSats installed on top of Artemis moon rocket . Spaceflight Now . 12 October 2021 . 22 October 2021.
  6. Web site: NASA Solar Sail Mission to Chase Tiny Asteroid After Artemis I Launch . . 20 January 2022 . Jet Propulsion Laboratory . NASA . 20 January 2022 . The target is 2020 GE, a near-Earth asteroid (NEA) that is less than 60abbr=offNaNabbr=off in size..
  7. Web site: Mahoney. Erin. NEA Scout. NASA. 14 January 2020. 11 March 2021.
  8. News: Status Update: Artemis 1's SmallSat Missions. 6 December 2022. David. Dickinson. Sky & Telescope . Sky&Telescope. 8 December 2022.
  9. Web site: Near Earth Asteroid Scout Mission. Castillo-Rogez. Julie. Abell. Paul. NASA . Lunar and Planetary Institute. July 2014. 11 March 2021.
  10. Web site: Status Report on Artemis I Secondary CubeSat Payloads. 17 November 2022. 18 November 2022. Doug. Messier. parabolicarc.com.
  11. Issam Ahmed . IssamAhmed . 1593427262032039936 . Was asking for an update on a cool side project from the Artemis 1 mission called NEA Scout, a small spaceship that sails on sunshine and is supposed to do recon of an asteroid. Turns out JPL hasn't yet established contact so it may be in trouble. Hope they get it going!. Thank you for your patience, Isaam. Here's a statement on NEA Scout's status: Following successful separation and deployment from the Space Launch System on Nov.16, NASA's Near-Earth Asteroid Scout (NEA Scout) project team has not yet established communications with the spacecraft. Teams continue working to initiate contact with NEA Scout. NEA Scout is a secondary payload for Artemis I and is a completely independent spacecraft. Orion is still on its way to the Moon. Updates will be provided as soon as possible on NASA's Artemis blog.. 18 November 2022.
  12. Book: Lightholder. Jack. Thompson. David R.. Castillo-Rogez. Julie. Basset. Christophe. 2019 IEEE Aerospace Conference . Near Earth Asteroid Scout CubeSat Science Data Retrieval Optimization Using Onboard Data Analysis . March 2019. https://ieeexplore.ieee.org/document/8742190. 1–7. 10.1109/AERO.2019.8742190. 978-1-5386-6854-2 . 195222320 .
  13. Book: McKinney. Colin. Goodsall. Timothy. Hoenk. Michael. Shelton. Jacob. Rumney. Keith. Basset. Christophe. Jeganathan. Muthu. Moore. Douglas. 2018 IEEE Aerospace Conference . Context cameras for the Orbiting Carbon Observatory 3 (OCO-3) instrument . March 2018. https://ieeexplore.ieee.org/document/8396759. 1–15. 10.1109/AERO.2018.8396759. 978-1-5386-2014-4 . 49540174 .
  14. Web site: NEA Scout Propulsion System. VACCO. 2021. 11 March 2021.
  15. Web site: Design and Development of NEA Scout Solar Sail Deployer Mechanism. Alexander R. Sobey . Tiffany Russell Lockett . NASA. 4 May 2016. 11 March 2021.
  16. Web site: Lessons Learned from the Flight Unit Testing of the Near Earth Asteroid Scout Flight System. NASA NTRS. 30 July 2019. 12 March 2021.
  17. Web site: Near Earth Asteroid (NEA) Scout. Les Johnson . Julie Castillo-Rogez . Jared Dervan . Leslie McNutt . NASA. 17 January 2017. 11 March 2021.
  18. Web site: Flex Dynamics Avoidance Control of the NEA Scout Solar Sail Spacecraft's Reaction Control System. Heaton Andrew. NASA. 17 January 2017. 11 March 2021.

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Near-Earth Asteroid Scout".

Except where otherwise indicated, Everything.Explained.Today is © Copyright 2009-2024, A B Cryer, All Rights Reserved. Cookie policy.