Rather than start a huge category on the right, I'm going to use this blog post to record some twitter addresses. I expect the coverage to be broader than the usual content of this blog. I also expect to gradually update the list over time.
U. S. Human Space Flight Plans Committee
NASA_HSF - The Committee will conduct an independent review of ongoing U.S. human space flight plans and programs, as well as alternatives.
AstroDude - Leroy Chiao - Astronaut and more...
NASAPrize - NASA Centennial Challenges
Regolith Excavation Challenge
Regolith_Chal - Regolith Excavation Challenge (a Centennial Challenge)
paulsrobotics - Serving all your robotic needs - http://www.paulsrobotics.com/
Space Elevator Games
segames - Ted Semon - Mojave, California - Official tweets from the Space Elevator Games
Northrop Grumman Lunar Lander Challenge
NGLLC09 - LunarLanderChallenge - Northrop Grumman Lunar Lander Challenge, presented by X PRIZE, and prize money from NASA
bonnova - design . innovation . lunar lander challenge team http://www.bonnova.com/
mastenspace - Masten Space Systems
colinake - Recent Georgia Tech Grad (09) working at GTRI and Masten Space Systems. Join me for musings on life, space, technology, and whatever.
wikkit - Ben Brockert - I moved from Iowa to the Mojave Desert to be a rocket scientist.
dmasten - Dave Masten
mojaverocketguy - Jonathan A. Goff - Your typical mild-mannered rocket engineer, dad, and entrepreneur
mmealling - Michael Mealing (Masten Space Systems)
Google Lunar X PRIZE
glxp - Google Lunar X PRIZE
OdysseyMoon - Odyssey Moon, Google Lunar X PRIZE team and commercial space venture
Bob_Richards - Space entrepreneur. Orphan of Apollo. Founder of International Space
University, Singularity University and Google Lunar X PRIZE competitor Odyssey Moon Ltd.
whitelabelspace - White Label Space (Google Lunar X PRIZE team) LunarX_EU - earlier White Label Space twitter
interorbital - Randa Milliron - CEO/CoFounder, Interorbital Systems and Trans Lunar Research SynergyMoon - Google Lunar XPRIZE entrant Team Synergy Moon
OmegaEnvoy - We are the Florida Team competing in the Google Lunar X PRIZE. We are students, engineers, entrepreneurs, and space geeks: Join us on our awesome adventure!
oe_rover - Omega Envoy Rover - I'm the Omega Envoy Rover being built to go to the moon to win the 30 million dollar Google Lunar X PRIZE. Follow me to the moon!
ARCAspace - Asociatia Romana pentru Cosmonautica si Aeronautica (ARCA) este o organizatie non-guvernamentala, lider national in domeniul cercetarii aerospatiale.
NextGiantLeap - Michael Joyce - A Google Lunar X PRIZE team
teamFREDNET - Team FREDNET is an open source and open participation competitor in the Google Lunar X PRIZE
csete - Alexandru Csete - I work with space, communications, video processing and related technologies. I blog for GLXP @teamfrednet.
jeffkrukin - NewSpace Business Development consultant, speaker, and writer
SoldTheMoon - David Gump - http://www.astrobotictech.com/ - private-sector space exploration
nprize - Paul Dear
NebulaAerospace - News from Nebula Aerospace (N-Prize team)
fineri - Iain Finer - Ametuer rocket engineer, aspiring song writer and musician.Just trying to live the dream.
ValkyrieFed - The Valkyrie Federation is a canadian (Quebec) entreprise, which has the goal of space exploration, and the lastest team on the N-Prize!
thomasspacecorp - Thomas Space Corp
Astronaut Glove Challenge
pkhomer - http://www.flagsuit.com/ - Astronaut Glove Guy
X PRIZE Foundation
alias_amanda - Amanda Stiles - Space maven, website designer, crowdsourcing evangelist, and engineer of the entrepreneurial variety.
GLXPFeeds - Google Lunar X PRIZE - Feeds and news related to the Google Lunar X PRIZE. You can follow a human at @glxp
Pomerantz - Will Pomerantz, Senior Director of Space Projects
PeterDiamandis - Peter Diamandis
nickyjor - aerospace eng,space lover, tech girl,dancer,pilot!! social media learner, fashion enthusiast,wine lover and well..I am simply a person who loves life
genomics_xprize - A $10 million prize to the first team to successfully sequence 100 human genomes in 10 days
i_2_i - 2 days at the United Nations that will change your world. June 8 + 9. NYC. How WILL you innovate in today's economy?
progautoxp - The official Progressive Automotive X PRIZE Twitter
HealthXPRIZE - Developing a $10M+ X PRIZE to fix health care
xprize - Radical Breakthroughs for the benefit of humanity
ConradAwards - Enabling young minds to connect education, innovation, and entrepreneurship.
inventioneer - nancy conrad - Chairman of Conrad Foundation
sedsusa - SEDS - The world's only student run space organization!
FIRSTAtlanta09 - FIRST Championship 2009 in Atlanta, Georgia
astrosociety - American Astronautical Society (listed here because of their CanSat competition coverage)
MoonBots - MoonBots: A Google Lunar X PRIZE LEGO® MINDSTORMS® Challenge
cswiki - Commercial Space Wiki (Ken Davidian)
richardbranson - Richard Branson (Chairman of Virgin Group)
rocketshadow - Aleta Jackson - I build rockets & rocket powered vehicles
rclague - Randall Clague
ikluft - Ian Kluft, Software Engineer and Commercial Pilot/Flight Instructor
Spaceport_NM - Spaceport America in New Mexico
ISPCS - International Symposium for Personal and Commercial Spaceflight
SpaceX_Media - cassie kloberdanz
ElonMusk - "I'm the genuine ElonMusk." muskfoundation.org teslamotors.com spacex.com solarcity.com paypal southafrica mars tolkien x.com blastar zip2 tosca kimb
mlaine - LiftPort - Building the Elevator to Space. Company Motto = "Change the world, or go home!" Author, Speaker, Consultant, Teacher, Venture Capitalist
ec_anderson - Eric Anderson, CEO of Space Adventures, serial entrepeneur.
edyson - Internet court jEsther
robinsnelson - Robin Snelson - looking for a few good rockets
Virgin_Galactic - The world's first commercial spaceline.
Frank4 - Frank Taylor - Google Earth Blogger and sailor. Also read TahinaExpedition.com
gearth - Google Earth - Grab Google Earth and the Google Pack here
GoogleMoon - Something truly out of this world is coming, you WILL want to follow us...Promise. Clue - Facebook, Twitter & The Moon
digitalearth - All of the latest news about Google Earth, Virtual Earth, Google Maps, etc.
spaceangels - Space Angels Network - Premier source of aerospace dealflow for investors and of early-stage capital for aerospace
burtonlee - www.linkedin.com/in/burtonlee
StephenFleming - Academic VC, professional investor, amateur rocketeer
4frontiers - 4Frontiers Corporation is an emerging space commerce company focused on the settlement of Mars.
the2suit - the (unofficial) real 2suit - as seen on History Channel The Universe - humanity is colonizing the universe in 2s ... Zero-G or Earth ultimate geek gadget FLY!
8C_Project - 8thContinentProject - Colorado School of Mines - The 8th Continent Project connects start-ups built on space technology – in energy, medicine, GPS, materials. We call it Space 2.0.
RichardGarriott - Computer Gaming Pioneer and Private Astronaut (1st 2nd Generation)
gozerog - a privately held space entertainment and tourism company http://www.gozerog.com/
nextstepinspace - Show Your Support for Commercial SpaceFlight!
NewSpaceNews - http://spacefront... - follow NewSpace News to stay informed about developments in the exciting entrepreneurial space arena! *Sponsored by SpaceIsle.com*
jeff_foust - Jeff Foust, Space industry analyst, writer, blogger, baseball fan
HobbySpacer - Clark Lindsey, Publisher and editor of HobbySpace.com and SpaceTransport News.com
SpaceShow - Dr. David Livingston, Host of The Space Show talk show
spacehack - a directory of ways to participate in space exploration. interact + connect with the space community.
milesobrien - Miles Obrien, freelance journalist
SpaceflightNow - Spaceflight Now
NASAWatch - NASA Watch
KeithCowing - Keith Cowing (NASA Watch, also see http://www.cowing.com/)
andrewchaikin - Andrew Chaikin
Free_Space - Irene Klotz blogs about what's happening off Earth
bencredible - Alpha nerd at Innovating Media and TechnologyEvangelist.com
SpaceFellowship - The International Space Fellowship (ISF) is an international news and information network dedicated to the development of the aerospace industry.
b0yle - Alan Boyle (MSNBC/Cosmic Log)
flspacereport - Edward Ellegood
xenijardin - Curator of Internet Esoterica, Anomalies, and Curiosities. BB co-editor, Boing Boing Video host/exec producer. http://tv.boingboing.net/
fitzwillie - Editor of GeekDad.com. That says a lot right there.
MichaelBelfiore - Michael Belfiore - Space & technology writer for Popular Science, Popular Mechanics, HarperCollins, and advanced technology companies.
flighthyperbola - Rob Coppinger is a recovering powerpoint user and engineer who mistakenly thought journalism was more glamorous than production engineering
UniGalactic - SpaceTravel Magazine - UniGalactic is a Unique Print Magazine Covering Space Tourism as well as Space Travel and Exploration Industries.
spacecom - Managing editor, Parabolicarc.com. Communications specialist. Have something to say. Let me help you say it.
robertpearlman - Editor, collectSPACE.com
collectspace - The Source for Space History & Artifacts
spaceteam - Fla Today Space Team - Live space updates at The Flame Trench, honored last year as the best beat reporting on the web.
Doug_Comstock - Director of NASA Innovative Partnerships Program (includes Centennial Challenges, FAST, SBIRs, etc)
worden - Pete Worden (NASA Ames Director)
waynehale - Wayne Hale (Former Flight Director)
gtwhitesides - George Whitesides
LADEE_NASA - Lunar Atmosphere and Dust Environment Explorer
LCROSS_NASA - NASA mission to explore the Moon and see if there is water ice near one of the lunar poles!
NASA_Ames_Web - NASA Ames Web
NASA_Wallops - NASA Wallops, Wallops Island, VA
PharmaSat - The PharmaSat experiment and flight system are designed to measure the influence of microgravity upon yeast resistance to an antifungal agent.
NASA_Greenspace - NASA_Greenspace
NLSI - NASA Lunar Science - Moon science rocks
NASAGoddard - Check out all the latest in NASA Goddard news and video!
Astro_Mike - Mike Massimino - NASA astronaut, mission specialist for STS-125 (Hubble Telescope servicing mission)
SPOTScott - Scott Parazynski - Drawn to explore high places, via spacecraft, aircraft and even on foot!
NewHorizons2015 - The First Space Mission to Explore Planet Pluto and the Kuiper Belt
flymetothemoon - NASA manager for LCROSS–NASA’s 1st mission back to the Moon, MoM/StepMoM, anthropologist, walker, chef, and BookBabe.
MarsRovers - Spirit and Oppy - Roaming the Red Planet on six wheels. The official mission Twitter of Spirit and Opportunity
jetlab - The latest news from the Jet Propulsion Laboratory. This Twitter is a service of SpaceLinks.net: http://spacelinks.net/
EarthObser - Earth Observatory from NASA
tedprize - TED Prize
airshipz - Airship Z-Prize - Airships for humanitarian logistics and environmental improvement. The Z-Prize is for successful development of freight airships!
SpaceFrontier - Space Frontier Foundation -People dedicated to opening the space frontier to human settlement
kimbal - Kimbal Musk
isdc - The International Space Development Conference is the premier space activist conference. See http://isdc.nss.org/
nss- National Space Society
spaceelevator - Cheap reliable access to space.
ewalker - Elaine Walker - Bio EPO, Mars Institute
airshipventures - Zeppelin Tours of the San Francisco Bay Area
arielwaldman - Ariel Waldman - Digital Anthropologist. Founder of Spacehack.org; CupcakeCamp. Engadget columnist. Previous NASA program coordinator, Pownce community manager.
antifaev - Youthful engineer/entrepreneur with a special affinity for anything awesome.
InnosightInstit - a non-profit think tank that applies Clayton Christensen’s theories of disruptive innovation to the social sector. See our recently published books to the left.
revrev - Mike Fabio - Community Manager at Google Lunar X PRIZE; musician; nerd; no I will not fix your computer.
fedcity - Diane Murphy
MDRSupdates - MDRS Official Update - You can go to Mars, but you can never leave!
YurisNight - A global celebration marking the anniversary of manned spaceflight.
LunarPioneer - Joel Raupe - Principal Investigator, Lunar Pioneer Research Group; Promoting extended human activity on Earth's Moon
TEMPO3 - Sci-fi 2 sci-fact (Mars Society artificial gravity smallsat project)
TEDMED - Marc Hodosh - TEDMED 2009: OCTOBER 27-30 IN SAN DIEGO! CHECK OUT WWW.TEDMED.COM AND REGISTER TODAY!
shellymurray1 - Michelle Murray - FAA AST Experimental Permit Program Lead
willjwatson - William Watson - Executive Director, Space Frontier Foundation
SpaceFrontier - SpaceFrontierFound'n - People dedicated to opening the space frontier to human settlement
jamesmuncy - Space policy/business consultant
kdavidian - Ken Davidian - One Exciting Challenge After Another
brettalexander - Bretton Alexander
lorettahidalgo - Loretta Whitesides - Co-creator of Yuri's Night, Zero-G Flight Director, and passionate about bring people together to made a huge difference on our home planet...
flight0001 - Russ Dale - Writer, journalist, paleoecologist, scientist, urban farmer, chef, space enthusiast, actor, comedian, space 2.0 advocate and human (featured in the gonzo Russ Dale X-Prize Cup Interview, I might add).
makerfaire - Maker Faire Bay Area May 30-31 (The World's Largest DIY Festival)
Murphian - Ian Murphy - PR expert specializing in Aerospace, Technology and Science
neiltyson - Neil deGrasse Tyson - Astrophysicist, American Museum of Natural History. Author: "The Pluto Files" & "Death By Black Hole"; Host: PBS NOVA scienceNOW
digitalart - Jim Plaxco - A digital artist and photographer specializing in astronomical art and abstract art
SpaceSolarPower - Space solar power satellites will provide Earth with abundant, clean electric power.
moonrangerlaura - Space enthusiast; Works on a space telescope; Loves scifi/fantasy, travel, podcasts, fiber arts and of course people. Not officially speaking for anyone but me
Apollo11TheGame - iPhone Game developed by Decode Interactive in conjunction with NASA.
GwenGriffin - Houston and often Cocoa Beach
TeslaMotors - The official Tesla twitter
BadAstronomer - Phil Plait - Astronomer, author, skeptic, funny guy, writer
SGAC - Space Generation Advisory Council in support of the United Nations Programme on Space Applications
Moon4You - space instrument bringing the benefits of the Moon back to Earth
ad_astra2 - Erika Wagner - Cambridge, MA (blogging at MIT Giant Leaps)
therealBuzz - Buzz Aldrin, Astronaut, Apollo XI, Gemini 12, Doctorate from MIT in astronautics, married to Lois Aldrin for 21 years. Korean War veteran - fighter pilot of 66 missions
ac_charania - http://planetarydefense.blogspot.com/
wingod - Dennis Wingo
EVA_Interviews - Eva-Jane Lark - EVA is creator and host of EVA Interviews: The Business of the new Space Age™ (and in real life a VP and Investment Advisor at a major Canadian investment co)
Moon - http://odysseymoon.com/ - Encouraging participation and collaboration among people interested in expanding humanity's social, legal and economic sphere to our sister world, the Moon.
TeamFREDNET - Team FREDNET is the open source competitor for the Google Lunar XPrize.
Astrogeology - http://astrogeology.usgs.gov/ - Astrogeology, alternatively known as planetary geology, is a planetary science discipline concerned with the geology of the celestial bodies such as the planets and their moons, asteroids, comets, and meteorites. The study of these rocks is similar to Earth-based geology.
Astronomy - For anyone intersted in Astronomy or Astrophotography.
Cosmology - Obsession of the Universe in its totality and humanity's place in it. Star seeking and theory, physics and awe.
LunarPioneers - http://lunarnetworks.blogspot.com/ - Lunar Pioneer is a long established "Society of Friends interested in exploration of the Moon," founded in 1977 as a private discussion club, the conversation intensified finally into an enterprise. Our goal remains unchanged: As the Rosetta Stone of the Solar System, Earth's Moon is also our Pier, our deep water port to our destiny.
Mars - http://martiansoil.com/ - All about the Planet Mars.
NASA - Encouraging participation and collaboration among people interested in NASA and space. News, views, and reviews to enlighten and inform.
SpaceFellowship - The International Space Fellowship (ISF) is an international news and information network dedicated to the development of the aerospace industry.
WaterRocket - You're a little Gyro Gearloose somehow and like to tinker with scientific stuff? This is your twibe!
geocaching - A place for geocachers to get together and see what other cachers are twittering about.
space - All things space & Earth & in between. NASA, commercial space, space industry, space geeks, dreamers, explorers. Welcome space tweeps!
Here's another, considerably longer and more comprehensive list that seems to have similar goals. It's too bad I didn't encounter it earlier. The coverage is somewhat different, since I'm going into prize and innovation topics that aren't specific to space, and this list covers a number of space areas I probably won't touch. I'd recommend checking the link below if you didn't find what you were looking for in the list above.
Twitter SpaceMeme - Space People, Missions, Agencies, Events ... - OnOrbit Colab Space
spacehack points out the following list of twitter sites from Star Stryder: astronomy-twitter-users. This list is mainly for astronomy sites of all sorts. The comments have more selections.
... and Ariel from spacehack also has the following list: Space-related web 2.0 accounts that are on my radar
... June 19 update: Follow active and former astronauts on Twitter - collectSPACE
... August 23 update: Top 50 Twitterrati for all of Space - Big on Good