Space Research

Here is information about Linux in Space, that is being collected by Tim Bird.

Most of this material will be eventually migrated to the Linux4Space wiki

Here is information about Open Source Software, and Linux in Space:

= List of things to Research =
 * Asteria details
 * LightSail details
 * Marco details
 * PhoneSat details
 * cFS
 * F-Prime

Related pages:
 * Research on Fault Tolerance
 * Research on space software
 * Schema for wiki pages for Linux-using spacecrafts
 * OSS Alternatives to Linux in CubeSats

= Documented missions with Linux in Space =

Cubesats
For general details about cubesats, including specification, programs and launch costs, see: CubeSats

TacSat-1 (2004)

 * TacSat-1 (2004 never launched), PowerPC x3, Linux 2.4

QuakeSat (2003)

 * QuakeSat (2003), PC 104 (intel?), Linux

MCubed-2 (2013)

 * MCubed-2 (2013) Stamp9G20 microcontoller, Linux ???

PhoneSat (2013)

 * PhoneSat (2013, ...) NASA, Google phones with Android 2.2
 * RESEARCH - what were the results? How did the COTS components do?

Perseus-M (2014)

 * By Aquila Space (which became Astro Digital)
 * https://web.archive.org/web/20160327122744/http://mstl.atl.calpoly.edu/~bklofas/Presentations/DevelopersWorkshop2015/Bertino_Perseus-M_Corvus-BC.pdf
 * used Linux and Python
 * Spacecraft tumbling causes voltage sag during charge
 * Notes:
 * Amperage readings in general have proven to have substantial errors. Don’t count on current monitors for critical tasks.
 * Ability to test and develop software on-orbit was extremely useful
 * Short development cycles can be extended past the launch date, and performance improvements can be made
 * Downside: extends the time to full operational status
 * Perseus-M “BenchSat” has proven extremely valuable for vetting code prior to upload
 * Linux, TCP/IP, Python, C, have all proven useful and allow for relatively rapid software development

Corvus-BC (2016?)

 * By Aquila Space (which became Astro Digital)
 * https://web.archive.org/web/20160327122744/http://mstl.atl.calpoly.edu/~bklofas/Presentations/DevelopersWorkshop2015/Bertino_Perseus-M_Corvus-BC.pdf
 * Has lots of detailed specs for hardware
 * Flight computer: ARM A8 running linux
 * COTS ARM A8 SOM with daughter board
 * Running Linux with Python and C
 * Power system: scalable 48Wh Li-Ion
 * Data Storage: 1 TB
 * GPS: Novatel OEM615
 * Ka-Band radio = 1Kg, 1U size, 10 and 40 Mpgs, requires 13W

Asteria cubesat (2017-2019)

 * By NASA JPL
 * https://www.jpl.nasa.gov/missions/arcsecond-space-telescope-enabling-research-in-astrophysics-asteria
 * Uses Linux and F-Prime, according to Tim Canham
 * https://www.jpl.nasa.gov/asteria-references
 * On-Orbit Results and Lessons Learned from the ASTERIA Space Telescope Mission (2018)
 * paper: https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=4067&context=smallsat
 * "ASTERIA uses the CORTEX 160 flight computer from Spaceflight Industries for onboard processing and command and data handling. It uses a Virtex 4FX FPGA with an embedded PowerPC processor running Linux."

The ASTERIA flight computer runs the Linux operating system and the flight software incorporates an ability to issue low-level commands directly to the shell. This flexibility has brought several key benefits during mission operations including an ability to diagnose anomalies via command line queries (e.g. ls and grep) and use compression (gzip) to increase effective downlink data volume. The shell interface is also used to send low-level payload commands to mitigate an issue that occasionally precludes imager initialization.


 * post-mortem talking about mission: https://www.space.com/asteria-proved-cubesats-can-study-exoplanets.html

Mission questions (for Asteria)
Here are questions about mission operations, hardware, power, software stack, etc.

Here are some questions about this mission:
 * recovery method for resets
 * OBC specs: processor(s), RAM, flash, storage
 * busses
 * linux version, from where obtained
 * customizations
 * kernel config
 * drivers you wrote
 * device tree you used
 * fault tolerance method
 * multiple boot chains, multiple processors
 * did mission succeed or fail
 * how long to provision?
 * how long to detumble?
 * launch date
 * deorbit date
 * power budget: battery size, solar panel max size, OBC power usage
 * build system used (buildroot, yocto project, other, homebrew scripts?)
 * standards adhered to (ESA?, NASA?)
 * user space stack elements: busybox?, f-Prime?, CFS?, libraries

Some of these are to answer the following questions:
 * which COTS hardware does the best and worst in space?
 * how many resets in LEO?
 * What are the presumed causes of resets?
 * is the processor permanently damaged by space use (not if the device recovers after a reboot)
 * what can a reboot recover from (electrical, thermal, radiation, vacuum)?
 * does the processor give out, or the software, or some other thing?
 * what is a good compromise strategy between COTS and custom hardware?
 * what is low cost, but still workable?

[ page conversion got to here ]

INCA (2022 - launch failure)

 * Ionospheric Neutron Content Analyzer, by New Mexico State University
 * from presentation at smallsat conference 2017:
 * presentation: https://digitalcommons.usu.edu/cgi/viewcontent.cgi?filename=0&article=3566&context=smallsat&type=additional
 * Using Atmel ARM9 processor
 * Embedded Linux allows large flexibility
 * Low power - Operates at 300mW
 * Lost in Astra launch of Feb 2022 (see BAMA-1)

Mars Cube one (MarCO) (2018)

 * Communications Relay cubesats
 * primary MARCO mission was to monitor communications of the Insight mission, during its EDL (Entry, Descent and Landing) phase


 * home page: https://www.jpl.nasa.gov/missions/mars-cube-one-marco
 * JPL press release with good info:
 * https://www.jpl.nasa.gov/news/press_kits/insight/launch/appendix/mars-cube-one/
 * flyby of Mars on Nov. 26, 2018
 * pioneered the CubeSat use of propellant to desaturate the attitude-control reaction wheels


 * https://en.wikipedia.org/wiki/Mars_Cube_One
 * launched May 5, 2018, deployed (separate from lander spacecraft shortly after launch (on way to Mars)


 * https://solarsystem.nasa.gov/news/834/10-things-cubesats-going-farther/
 * has some very nice pictures of the satellites

R5-S1 (2022, launch failure)(not sure it was Linux)

 * Johnson Space Center demo mission
 * destroyed in Astra Feb 2022 launch failure (See BAMA-1)

petitSat (2023 - not sure it was Linux)

 * from NASA’s Goddard Spaceflight Center

SPORT (2023 - not sure it was Linux)

 * from NASA’s Marshall Space Flight Center

Aalto-1 cubesat (2017-2021?)
See Aalto-1

VZLUSAT-2 (2023-)

 * by VZLU (Czech Aerospace Research Centre)
 * home page: https://www.vzlusat2.cz/en/
 * Launched Jan 13, 2023, deployed Jan 27 from D-Orbit carrier (which had 105 total satellites to launch)
 * Uses Linux
 * Lenka mentioned that the seed for the Linux4Space github repository is an existing version of Linux developed with YP for space
 * is part of the SatNogs network
 * telemetry and realtime stats available here: https://dashboard.satnogs.org/d/L8ywE9oMz/vzlusat-2?orgId=1

LightSail 1 (A) (2015)

 * by the Planetary Society
 * See https://www.planetary.org/sci-tech/lightsail-academic-resources
 * see specifically:
 * https://planetary.s3.amazonaws.com/projects/lightsail/papers/Ridenoure-et-al-2015-status.pdf
 * Tyvek Intrepid computer board (v6) with Atmel processor and Linux OS

LightSail 2 (B) (2019-2022)

 * by the Planetary Society
 * home page: https://www.planetary.org/sci-tech/lightsail
 * See https://www.planetary.org/sci-tech/lightsail-academic-resources
 * see specifically:
 * https://planetary.s3.amazonaws.com/projects/lightsail/papers/Ridenoure-et-al-2015-one-down.pdf
 * Tyvek Intrepid computer board (v6) with Atmel processor and Linux OS
 * notes: there was no ability to load new software to the software, but some parameters (particularly sensor sampling rates) were configurable

Pi-Sat (2016)

 * Pi-Sat - https://www.nasa.gov/feature/goddard/2016/students-experience-nasa-satellites-101

NASA Cubesat Launch Initiative (2013-present)

 * https://www.nasa.gov/directorates/heo/home/CubeSats_initiative
 * Recent news (November 2022)
 * https://blogs.nasa.gov/smallsatellites/2022/11/18/educational-cubesats-set-to-launch-to-the-space-station/
 * 150th deployment of cubesats from ISS (Dec 2022)
 * https://www.nasa.gov/image-feature/nasa-cubesat-launch-initiative-deploys-150th-from-space-station

Starlink

 * https://www.zdnet.com/article/spacex-weve-launched-32000-linux-computers-into-space-for-starlink-internet/
 * reddit discussion thread: https://old.reddit.com/r/spacex/comments/gxb7j1/we_are_the_spacex_software_team_ask_us_anything/?limit=500

Perseverance mission (multiple uses)
The Perserverance mission included Linux in 3 different elements:
 * Perseverance EDL (Entry, Descent, and Landing) cameras
 * Ingenuity Helicopter
 * Perseverance helicopter base station


 * Linux on Mars: How the Perseverance Rover and Ingenuity Helicopter Leveraged Linux to Accomplish their Mission - Tim Canham, ELC 2021
 * slides: https://elinux.org/images/5/5a/1._TIMOTHY_CANHAM.pdf
 * video: https://youtu.be/0_GfMcBmbCg
 * notes:
 * video covers Linux use on all three components (EDL camera system, helicopter, and radio base station)
 * F-Prime used on base station, and in helicopter (on 2 different processors (one Linux and one baremetal)

EDL camera system
The EDL Camera system used an x86-based Linux system, with USB cameras spread throughout the vehicle.

Ignenuity Mars Helicopter

 * overview page: https://en.wikipedia.org/wiki/Ingenuity_(helicopter)
 * notes:
 * kernel version: 3.4 (from vendor: qualcomm)
 * RESEARCH: what was modified?


 * Notes from ELC keynote talk:
 * F-Prime running on Linux, and on TI processor (baremetal) and on base station
 * can execute arbitrary commands on Linux command line
 * Uses stdlib system API call
 * Have done:
 * bzip2 - to compress log files
 * md5sum, ls, rm
 * bash shell commands for various cleanup tasks
 * Use “taskset –c” to select which core to run programs on

See Thursday, December 12, Day 4, talk #3 in the list:
 * FSW 2019 talk by Tim Canham -
 * slides: https://flightsoftware.jhuapl.edu/files/_site/workshops/old_archive/2019/
 * online: https://drive.google.com/file/d/12Mt5H4_AzshF4OmGXHHCocibbcn80R5r/view?usp=share_link
 * local copy: [[file:3-FSW_Conf2019_v3.pdf]]
 * video: https://youtu.be/mQu9m4MG5Gc
 * notes:
 * small features on Qualcomm processor don't dissipate a lot of energy in an upset event
 * not as unreliable as you might think
 * things that are problems are the analog circuits that support the processor
 * qualcomm processor = 30,000 DMIPS vs 200 for a traditional rad-hardened processor


 * FSW 2022 talk by Tim Canham
 * video: https://www.youtube.com/watch?v=D-Y6H0GMtbM
 * slides:
 * online: https://drive.google.com/file/d/10tMuykGB7n8ZgksIjdOPwQHFyEeBC_XH/view
 * local: [[file:D3-07 - Ingenuity Mars Helicopter Operations Overview by Timothy Canham from NASA JPL.pdf]]


 * notes:
 * Uses F-Prime on Linux, on the qualcomm, and F-Prime baremetal on the TI chip
 * good overview of operations so far
 * command sequencing, delays, radio transmissions, etc.
 * has information about anomolies, and how they were fixed
 * watchdog issue at beginning of mission
 * wrong timestamp on images

helicopter base station (on rover)
Qualcomm processor same as on helicopter?

= Projects =

FlightLinux (1999-2002)
Paper: https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=1513&context=smallsat discussed OpenFlightLinux, among other things
 * was designed and used in some spacecraft by NASA
 * original website: http://flightlinux.gsfc.nasa.gov/ (no longer online)
 * archive copy: https://web.archive.org/web/20070612193927/http://flightlinux.gsfc.nasa.gov/
 * articles:
 * https://www.linux.com/news/flightlinux-tux-space/
 * FlightLinux: Tux in Space, JT Smith for Linux.com, March 14, 2001
 * interview with Pat Stakem, who initiated the project
 * Lots of details
 * says that FlightLinux was based on "BlueCat" Linux, from LynuxWorks, due to support for RealTime
 * However, as of 2001, the official site said it was based on ELKS, with the intent to switch to BlueCat
 * https://pl.wikipedia.org/wiki/FlightLinux
 * says that FlightLinux was based on ELKS (for realtime performance)
 * was slated for use on [|UoSAT-12] but this didn't happen
 * never flew in space
 * project was discontinued in 2002
 * original web site is no longer available: http://flightlinux.gsfc.nasa.gov/
 * Final Report: https://web.archive.org/web/20070711192746/http://flightlinux.gsfc.nasa.gov/docs/FlightLinux_final.pdf
 * describes difficulties getting Linux to run on the hardware
 * lack of debugging capability was a big problem
 * government bureaucracy wouldn't let them publish their (very small) changes to Linux, due to ITAR trade restrictions
 * also built a fairly strong community interest in the project
 * has copies of lots of e-mails between Patrick and groups working on Linux
 * Lessons Learned: https://web.archive.org/web/20070711192857/http://flightlinux.gsfc.nasa.gov/docs/FlightLinux_LL.pdf
 * Linux compatibility with OBC was very hard (no BIOS, triple-redundant memory, etc.)
 * They couldn't boot the kernel for a long time, and ran out of money to finish the project
 * OpenFlightLinux.org tried to revive it in 2007:
 * see https://www.linux.com/news/flightlinux-blasts-again/
 * also see the presentation at the small sat conference that year
 * Abstract: https://digitalcommons.usu.edu/smallsat/2007/all2007/80/
 * FlightLinux is described in this presentation (slide 7):
 * file:///home/tbird/Downloads/SSC07-XII-3.pdf
 * Note that Pat Stakem appears to be the leader of this project again
 * Site was never well-developed. See a plea for help with basically all aspects of development, here: (see "Hop On Board" at bottom of page)
 * https://web.archive.org/web/20070911093308/http://www.openflightlinux.org/?page_id=2

French Linux4Space (2020)

 * home page: ?
 * see [[file:Linux for space applications (LEE%%233)-Pierre-Fixheux.pdf]]

Linux4Space (2022)

 * Linux4Space
 * home page: https://linux4space.org
 * ELCE 2022 Presentation: https://linux4space.org/static/logo/Linux4Space-Session.pdf
 * [|pdf] and [|video]
 * wiki: https://wiki.linux4space.org/wiki/Main_Page

F-Prime Flight software (2013-)

 * home page: https://nasa.github.io/fprime/
 * repository: https://github.com/nasa/fprime
 * see https://digitalcommons.usu.edu/smallsat/2018/all2018/328/
 * paper: https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=4140&context=smallsat
 * presentation about F-Prime in 2018 (at smallsat conference)
 * slides: file:///home/tbird/Downloads/F_Prime_AnOpen-SourceFrameworkForSmallScaleFlightSoftwareSystems-RobertBocchino.pdf
 * Was used with Linux for many NASA JPL projects (Asteria, Ingenuity, etc.)
 * Notes:
 * F Prime Prime = a new tool for specifying models (in progress in 2018)
 * Are working on tools for visualization and graphical editing
 * This talk has a very interesting section on testing, and testing philosophy

autogenerated, written in C++
 * Resources:
 * [|FSW 2021: Leveraging Open Source Development to Enhance the F Prime FSW Framework]
 * Michael Starch - NASA JPL
 * Notes:
 * Don't just dump something on github
 * uses normal git workflow: master branch for users, development branch for integration, forks and pull requests for actual development work
 * static analysis with lgtm (looks good to me) https://lgtm.com/
 * doxygen and sphynx - code from comments
 * separate product line from project (preserve generalizations)
 * https://github.com/cookiecutter/cookiecutter - to make projects from templates
 * what is difference between F-prime and cFS:
 * cFS uses an embedded bus between modules, written in C
 * F-prime uses point-to-point communication between modules, that is
 * your flight software topography is static after design

cFS

 * core Flight System - from Goddard Space Center
 * home page: https://cfs.gsfc.nasa.gov/
 * mailing list (community): https://github.com/nasa/cFS/blob/main/README.md#join-the-mailing-list
 * github repos:
 * main cFS bundle: https://github.com/nasa/cFS
 * Operating System Abstraction Layer: https://github.com/nasa/osal
 * core flight executive: https://github.com/nasa/cFE
 * Platform Support Package: https://github.com/nasa/PSP
 * there are many specific flight software components listed here:
 * https://github.com/nasa/cFS#other-cfs-related-elementstoolsappsdistributions

KubOS Flight Software

 * includes KubOS Linux, owned by [|Xplore]
 * repos: https://github.com/kubos
 * main kubos repo: https://github.com/kubos/kubos
 * see https://docs.kubos.com/1.21.0/ecosystem/index.html
 * in April 2022, Xplore acquired KubOS corp, and their "Major Tom" flight control software
 * https://spacenews.com/xplore-acquires-kubos/
 * KubOS partners and customers included RBC Signals, Viasat, Microsoft Azure and ISISpace of the Netherlands, and Xplore
 * Tyler Bowder, KubOS CEO and Founder (and presumably KubOS developer) is a Xplore employee

= Companies and Organizations =

Spaceflight Industries

 * Spaceflight Industries
 * Product: CORTEX 160 flight computer from Spaceflight Industries, on the ASTERIA mission

NASA, Jet Propulsion Laboratory

 * People:
 * Tim Canham = flight software lead for Ingenuity mission (member of small scale flight software group)
 * Jeff Levison, Supervisor, Small Scale Flight Software Group
 * Rob Bocchino, flight software lead for the ASTERIA CubeSat (member of small scale flight software group)

Planet Labs

 * See https://en.wikipedia.org/wiki/Planet_Labs
 * and https://www.planet.com/
 * Dove Satellites
 * mention of Linux, Ubuntu, and Debian in this small sat. conference paper:
 * abstract: https://digitalcommons.usu.edu/smallsat/2017/all2017/138/
 * paper: https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=3669&context=smallsat
 * presentation: https://digitalcommons.usu.edu/cgi/viewcontent.cgi?filename=1&article=3669&context=smallsat&type=additional
 * it appears that python, scipy were used onboard the satellite for ADCS calculations and calibration
 * not much more detail than that

Astro Digital

 * https://www.astrodigital.com/
 * formerly Aquila Space, in the imaging business
 * missions = Perseus-M1,2, Corvus-BC,2,3 satellites (some still operational)

SpaceX

 * Uses Linux in Falcon 9 and Dragon spacecraft, and Starlink satellites
 * Embedded Linux Conference 2013 keynote:
 * See https://lwn.net/Articles/540368/
 * By Robert Rose, former VP of Software Engineering
 * Robert has sinced moved on and is president of a robotics company

Dragon Flight Software

 * https://www.zdnet.com/article/from-earth-to-orbit-with-linux-and-spacex/

Avionics

 * https://youtu.be/QgzdA3fzu8o?t=1606 - Jinna Hosein, USENIX 2016 talk
 * Linux systems used by SpaceX
 * Falcon 9
 * 3 Linux flight-control computers on every first stage
 * flight-control is C++ user-space application (that is "compiled in"?)
 * 3 Linux telemetry/rf communicatons computers on first stage
 * 3 flight control on second stage
 * 3 telemetry/rf computers on second stage
 * ethernet is primary bus on flight vehicles
 * dragon also has Linux systems
 * some ground support systems have Linux

Spacex people

 * Jinnah Hosein, SpaceX
 * https://youtu.be/QgzdA3fzu8o - USENIX 2016, LISA16
 * good description of voting, Linux systems, and testing as well
 * commentary on same presentation at Game Developer Conference 2015:
 * https://www.reddit.com/r/spacex/comments/2y14y4/engineer_the_future_session_with_jinnah_hosein_vp/

Boeing

 * Boeing is heading the ELISA working group
 * I contacted Christopher Wood, who did not know of any Boeing efforts with Linux in space
 * he didn't respond when I asked about Boeing and ELISA
 * Steven H. VanderLeest - head of Aerospace working group in Boeing
 * see https://www.linux.com/news/linux-in-aerospace-a-personal-journey/ (Nov 2022)
 * For flight control, Linux needs:
 * fast performance: io_uring, fast boot time
 * determinism: boot time and response time (interesting)
 * embedded characteristics: limited size, weight and power
 * mobile phones help with this
 * also need driver support
 * assurance: must meet standards and required confidence level
 * expert peer review
 * formal verification
 * aviation standard is DO-178C (levels E through A)
 * since Linux was not designed for Aerospace, it's harder to demonstrate correct design to regulators

Schools

 * Schools that have cubesat programs:
 * Universtiy of Colorado, Boulder (2017)
 * Cornell University (2018)
 * Aalto University, Finland (2011-2021)
 * University of Alabama [|UASpace]- BAMA1 cubesat (2022, failed), BAMA-2 (target=May 2023)
 * BAMA-1 (launch failure by Astra in 2022) - https://www.space.com/astra-first-florida-launch-failure-february-2022
 * BAMA-2 - target= May 2023
 * University of California, Berkely [|STAC] - QubeSat (2021?)
 * see [|Qubesat news]
 * project site: https://stac.berkeley.edu/project/qubesat
 * New Mexico State University - Inca
 * Inca - https://digitalcommons.usu.edu/smallsat/2017/all2017/35/
 * University of Michigan - Mario (2023)
 * see https://blogs.nasa.gov/smallsatellites/2022/11/18/educational-cubesats-set-to-launch-to-the-space-station/
 * Thomas Jefferson High Schol for Sciences and Technology (2013-present) - TJREVERB (2023)
 * see https://blogs.nasa.gov/smallsatellites/2022/11/18/educational-cubesats-set-to-launch-to-the-space-station/

University of Tokyo

 * University of Tokyo
 * Groups:
 * [|UTOPS] = University of Tokyo Organization for Planetary Space Science - Tricom-1R (2018), AQT-D (2019), StarSphere (2023)
 * [|Thruster research at University of Tokyo]
 * [|Tricom-1R] - Feb 2018 to Aug 2018 - store and forward network test
 * [|AQT-D] - 2019 - test of resitojet water propulsion
 * [|ISSL] = Intelligent Space Systems Laboratory
 * Led by Professor Nakasuka Shinichi
 * http://www.aeroeng-lab.t.u-tokyo.ac.jp/en/ - Advanced Aeropropulsion Laboratory, Department of Aeronautics and Astronautics, The University of Tokyo

= People =

Patrick Stakem

 * Patrick Stakem
 * Teaches at Capitol Technology University (2017?)
 * wrote several books on cubesats:(can be found on Amazon) with search by Author
 * from 'Cubesats Engineering' description: "Cubesats are modular, built to a standard, and mostly open-source. The downside is, approximately 50% of Cubesat missions fail. We hope to point out some approaches to improve this."

= Linux Stuff on the Shuttle or ISS =

Linux on Space Shuttle (STS 83) (1997)

 * https://web.archive.org/web/20070610195240/http://www.faho.rwth-aachen.de/~matthi/linux/LinuxInSpace.html
 * Linux was on-board, but STS 83 had fuel cell problems and mission was aborted early
 * It appears that the experiment was conducted on STS 94, as this mission performed the same micro-gravity experiments that STS 83 was supposed to do.
 * used Linux in a micro-gravity experiment
 * It uses a miniature '486 PC-compatible computer, the Ampro CoreModule 4DXi. Debian GNU/Linux is loaded on this system in place of DOS or Windows. The fragility and power drain of disk drives ruled them out for this experiment, and a solid-state disk replacement from the SanDisk company is used in their place. The entire system uses only 10 watts", said Kuzminsky, as much electricity as a night-light. "The computer controls an experiment in hydroponics, or the growth of plants without soil", said Kuzminsky. "It controls water and light for the growing plants, and sends telemetry and video of the plants to the ground".

Astro-Pi (2015-..)

 * Astro-Pi Mission Space Lab - https://astro-pi.org/
 * https://astro-pi.org/mission-space-lab/
 * raspberry pi on the ISS that can be controlled from the ground
 * students can run experiments on the device
 * https://youtu.be/owcZeUnSixM - discussion of astro-pi and new features
 * launched in 2015 by
 * old one in operation for 7 years
 * 2 new pis now, with new sensors, on the ISS now (Jan 2023)
 * Sony 12.3 MP IMX477 image sensor

Spaceborne Supercomputer

 * Ran Linux on a high-performance computer for 207 days straight on the ISS
 * See https://www.nasa.gov/mission_pages/station/research/news/b4h-3rd/eds-new-approach-radiation-hardening
 * Launched in August 2017, it was on the ISS for 615 days (worked for 658 days? - see podcast transcript)
 * HP home page: https://www.hpe.com/us/en/compute/hpc/supercomputing/spaceborne.html
 * spaceborne-2 launched in Feb. 2022?
 * includes GPUs for some calculations
 * https://www.zdnet.com/article/hpe-and-nasa-to-launch-second-spaceborne-computer-into-orbit/
 * https://spacenews.com/spaceborne-computer-2-first-results/ - showing results, more experiments in pipeline
 * spaceborne computer podcast: https://www.nasa.gov/johnson/HWHAP/spaceborne-computer - Feb 19, 2021
 * about Spaceborne-2 computer

= Conferences =

Small Satellite Conference

 * [|Small Satellite Conference]
 * has been running for over 30 years!
 * Proceedings - https://digitalcommons.usu.edu/smallsat/
 * Hosted by Utah State University (Logan, Utah)
 * Aug 5-10, 2023

4S Symposium

 * 4S symposium in Europe??
 * Small Satellites Systems and Services
 * web page (for 2022): https://atpi.eventsair.com/QuickEventWebsitePortal/4s-symposium2022/website

Space Symposium

 * https://www.spacesymposium.org/

SmallSat Symposium

 * https://2023.smallsatshow.com/
 * Feb 7-9, 2023, Mountain View, CA
 * $1400 (in-person early bird)

= Sony Satellite Projects =

StarSphere

 * [|StarSphere]
 * Sony camera in space with a service for end-users to take pictures and videos at scheduled times
 * Launched Jan 3, 2023 on SpaceX Transporter 6 Rideshare mission (which had 114 satellites)
 * RESEARCH NEEDED - what is the hardware and software for this satellite
 * JAXA, U of Tokyo, Sony were the creators
 * see https://news.mynavi.jp/techplus/article/20201113-1489186/ for details of people and origin of project
 * Satellite "bus" was done by U of Tokyo
 * Camera was done by Sony
 * Sony people quoted in techplus article:
 * Yoshihiro Nakanishi, Space Entertainment Preparation Office, New Business Development Division, Sony Business Development Platform
 * Mr. Mao Zen, satellite development leader
 * Masao All, Sony's satellite development leader. In the past, he has been involved in semiconductor design, such as designing LSIs for TVs and developing image sensors for mobile devices. He currently works as a system engineer for TV models
 * JAXA people quotes in the techplus article:
 * Koichi Fujihira, J-SPARC Producer of JAXA's New Business Promotion Department
 * some facts:
 * 2-year lifespan, water-propulsion, Sony high-end camera

Water propulsion system
engine on AQUA mission (2019)
 * https://youtu.be/x4pUQr-5aYU - Pale Blue product description video
 * see https://pale-blue.co.jp/product/
 * 2 products:
 * resistojet = water (steam) from electricity
 * Resistojet used in Starsphere, 20W power, >50 ISP, 1mN thrust, 1.5Kg wet mass
 * water ion thruster = ions from microwaves (ECR)
 * water propulsion: water plasma created by Electron Cyclotron Resonance
 * Same company has a ECR ion thruster, but I don't think that's the same as the resitojet (see the product page)
 * see https://www.sciencedirect.com/topics/chemistry/electron-cyclotron-resonance
 * see https://en.wikipedia.org/wiki/Electron_cyclotron_resonance
 * possibly by this group?: https://iopscience.iop.org/article/10.1088/1361-6595/aba2ac/meta
 * ResistoJet - tested on [|AQT-D] mission
 * see https://www.jstage.jst.go.jp/article/tastj/18/4/18_18.141/_article
 * see https://jasakawa9.wixsite.com/website - description of resistojet
 * paper at small satellite conference 2019: https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=4398&context=smallsat

Mission updates

 * CES coverage by "Ellie in Space" - Jan 2023
 * https://youtu.be/OOw31oQ9kOE


 * mission updates: - Feb 2023
 * first photo: https://petapixel.com/2023/02/28/this-is-the-first-photo-shot-with-sonys-star-sphere-satellite/


 * Gunter's page on this: https://space.skyrocket.de/doc_sdat/eye.htm

SPRESENSE in space

 * Sony Spresense board in space
 * Innovative Satellite Technology Demonstration No. 2 (ISTD?)
 * Launch vehicle: Epsilon Rocket No. 5
 * Launch location: Uchinoura Space Center, Japan
 * Launch date: Nov 9, 2021
 * [|Innovative Satellite Technology Demonstration Program]
 * SPRESENSE semiconductor details:
 * https://www.kenkai.jaxa.jp/kakushin/interview/02/interview02_03.html
 * Sony representatives:
 * Sony Semiconductor Solutions Corporation
 * Yoshinori Ota Product Department 1, IoT Solution Division
 * Mr. Masaharu Nagata of Sony Group Corporation
 * SPRESENSE has low power and high throughput (especially for AI)
 * FD-SOI (Fully Depleted Silicon On Insulator) does well with radiation as well as low power.
 * did special tests for space-worthiness:
 * proton irradiation, thermal vacuum, vibration/shock


 * Universe cubesat (UNVRS?)
 * SORA-Q?
 * see https://developer.sony.com/posts/the-spresense-microcontroller-board-launched-in-space/

= Japan cubesat, microsat and small rover projects =
 * Tohoku University - Professor Kazuya Yoshida
 * TEDx talk - 2014 - Rising into space [|video link]

SORA-Q

 * SORA-Q - Transformable Lunar Rover
 * Small, rolling, transformer robot
 * sources:
 * JAXA announcement (May 2021) - https://global.jaxa.jp/press/2021/05/20210527-1_e.html
 * https://www.space.com/japan-transformable-moon-robot-ispace-2022-lunar-lander - space.com coverage of May 2021 announcement
 * https://gizmodo.com/spacex-ispace-lunar-mission-hakuto-r-m1-1849884016
 * design award, and list of collaborators: https://www.g-mark.org/award/describe/53666?locale=en
 * [|YouTube video]
 * https://www.smithsonianmag.com/science-nature/these-five-innovative-rovers-will-soon-explore-the-moon-180980819/
 * https://developer.sony.com/posts/the-spresense-microcontroller-board-launched-in-space/
 * details:
 * Ridesharing on the Hakuta R M1 mission
 * It seems to include Spresense processor (and NuttX)?

Hakuta R mission

 * Hakuta R mission
 * sources:
 * https://ispace-inc.com/m1
 * Lunar Lander
 * JAXA announcement: https://ispace-inc.com/news-en/?p=2547
 * Lander by 'ispace' private company in Japan
 * launched in Dec 2022, should land April 202

Dealing with hardware resets in space:

= Fault rates and fault tolerance =

OBC reset data
See Aalto final results paper.

from: https://www.nasa.gov/centers/ames/engineering/projects/phonesat2.html

"PhoneSat 2.4 continues to transmit data, which means its solar arrays, battery charging circuit, Arduino watchdog and data router are still operating correctly. In early January, however, the Phonesat 2.4 smartphone began to experience recurring resets coinciding with a period of numerous solar flares. As a result, the satellite no longer executes flight application software.

Radiation tolerance using Actor-Judge architecture and "flight strings"
SpaceX uses flight strings and triple modular redundancy for fault tolerance.


 * https://space.stackexchange.com/questions/9243/what-computer-and-software-is-used-by-the-falcon-9
 * description of Falcon-9 "flight-string" voting system
 * see https://youtu.be/QgzdA3fzu8o?t=1343 - Jinnah Hosein 2016 Usenix talk
 * one flight-string different = use voting
 * second computer not responding = use computer that was in consensus most recently
 * https://web.archive.org/web/20131203204735/http://www.aviationweek.com/Blogs.aspx?plckBlogId=Blog%3a04ce340e-4b63-4d23-9695-d49ab661f385&plckPostId=Blog%3a04ce340e-4b63-4d23-9695-d49ab661f385Post%3aa8b87703-93f9-4cdf-885f-9429605e14df - Nov. 2012 interview with John Muratore
 * aviation week article with more detail about radiation tolerance
 * on one mission to ISS a computer went down, and they decided to leave it turned off instead of reboot it
 * 2 processors x 3 flight control computers
 * flight-string voting
 * re-sync - 3 copies of memory, rebooted computer can re-establish context and come into sync with other computers

= Plans for Open Source =

NASA High Performance Spaceflight Computer

 * https://www.eejournal.com/article/nasa-recruits-microchip-sifive-and-risc-v-to-develop-12-core-processor-soc-for-autonomous-space-missions/
 * JPL selected Microchip to design SoC based on 8 RISC-V cores from SiFive, with 4 additional RISC-V cores added for general-purpose computing
 * in 2018, Wesley Power, Assistant Chief for Technology at NASA Goddard Space Flight Centers Electrical Engineering Division, had a presentation that showed HPSC with 8 ARM processors

= Overview Papers on Linux usage in space =
 * Current use of Linux in spacecraft flight software (2017)
 * Hannu Leppinen, Aalto University, IEEE Aerospace and Electronic Systems Magazine, October 2017
 * abstract: https://www.researchgate.net/publication/321788741_Current_use_of_linux_in_spacecraft_flight_software
 * paper: https://www.researchgate.net/profile/Hannu-Leppinen/publication/321788741_Current_use_of_linux_in_spacecraft_flight_software/links/5a4f2319458515e71b08f243/Current-use-of-linux-in-spacecraft-flight-software.pdf
 * local copy: [[file:current-uses-of-Linux-in-space-research-paper-2017.pdf]]
 * IEEE publication local copy: [[file:2017 Leppinen - Current use of Linux in spacecraft flight software.pdf]]
 * IEEE A&E SYSTEMS MAGAZINE, October 2017
 * excellent overview of Linux in several different spacecraft
 * [RESEARCH] - from his Aalto1 dissertation


 * Linux and the Spacecraft Flight Software Environment (2007)
 * Edward Birrane, et. al Johns Hopkins, AIAA/USU Conference on Small Satellites, 2007
 * Abstract: https://digitalcommons.usu.edu/smallsat/2007/all2007/87/
 * Paper: https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=1520&context=smallsat
 * talks about using RTLinux on Rad-hardened processors


 * The Use of Carrier Grade Linux in Space (2007)
 * Mike Anderson, The PTR Group, AIAA/USU Conference on Small Satellites, 2007
 * Abstract: https://digitalcommons.usu.edu/smallsat/2007/all2007/86/
 * Paper: https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=1519&context=smallsat
 * Presentation: https://digitalcommons.usu.edu/cgi/viewcontent.cgi?filename=0&article=1519&context=smallsat&type=additional


 * Open Source Software for Small Satellites (2007)
 * Patrick Stakem, OpenFlightLinux.org, Conf. on Small Satellites, 2007
 * Abstract: https://digitalcommons.usu.edu/smallsat/2007/all2007/80/
 * Paper: https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=1513&context=smallsat
 * discussed OpenFlightLinux, among other things


 * Democratizing Access to Space: Kube Platform for CubeSat (2022)
 * Minsik Lee, IBM Space, AIAA/USU Conference on Small Satellites, 2022
 * Abstract: https://digitalcommons.usu.edu/smallsat/2022/all2022/341/
 * Paper: There is no paper!!


 * An Evaluation of Potentional Compute Platforms for Picosatellites (2022)
 * Ofir Cohen and Sivan Toledo, Tel-Aviv University, Conf. on Small Satellites, 2022
 * Abstract: https://digitalcommons.usu.edu/smallsat/2022/all2022/206/
 * "We show that suitable hardware does exist, but that it is not yet supported well enough to allow small teams to use it in satellites or other specialized sensor nodes."
 * Paper: https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=5365&context=smallsat
 * Discuses several platform (mostly from a hardware perspective)
 * Includes discussions of Linux, raspberry Pi zero, etc.

See also:
 * OpenSatKit Enables Quick Startup for CubeSat Missions (2017)
 * Nasa Goddard Space Flight Center
 * Abstract: https://digitalcommons.usu.edu/smallsat/2017/all2017/69/
 * The Open Source Microsatellite Platform
 * KISPE Space Systems Limited
 * Abstract: https://digitalcommons.usu.edu/smallsat/2019/all2019/242/
 * Paper: No Paper, was a poster, document not available

= Generic sources with Linux in Space references =
 * https://space.stackexchange.com/questions/13436/successful-linux-based-cubesat-missions?rq=1
 * https://space.stackexchange.com/questions/21839/does-anybody-work-on-a-spacecraft-linux (2017)
 * Kubos - https://github.com/kubos
 * Tyvak - http://www.tyvak.com/platform/microsat-solutions/
 * https://www.cubesatshop.com/product/isis-on-board-computer/

= Linux-based satellite boards =

Pumpkin ($7k)

 * https://www.pumpkinspace.com/store/p208/mbm2.html
 * based on beaglebone black

ISIS Space OBC ($4K-$6K)

 * https://www.isispace.nl/product/on-board-computer/
 * ARM9 at 400 MHZ
 * Comes with FreeRTOS, but compatible with KubOS

BeagleBoneBlack

 * See https://docs.kubos.com/1.21.0/obc-docs/bbb/installing-linux-bbb.html
 * compatible with KubOS

= Resources =
 * Union of Concerned Scientist satellite database: https://www.ucsusa.org/resources/satellite-database
 * this is mostly used to track whether satellites are being used for nefarious purposes

CubeSat Page Template - Use this when creating a new CubeSat page

= Not Linux (graveyard) =

Lunar Flashlight? (2023-?) (not Linux)

 * This satellite is running vxworks (not Linux)
 * per a conversation with JPL in Feb 2023
 * home page: https://www.jpl.nasa.gov/missions/lunar-flashlight
 * wikipedia page: https://en.wikipedia.org/wiki/Lunar_Flashlight
 * other articles:
 * Systems Integration and Test of the Lunar Flashlight Spacecraft
 * Small Sat Conference 2022
 * abstract: https://digitalcommons.usu.edu/smallsat/2022/all2022/149/
 * paper: https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=5308&context=smallsat
 * info:
 * is using new ASCENT propulsion, but is having [|propulsion difficulties]
 * uses Sphinx low-power, radiation tolerant flight computer