• Astrobiology & Life Science: Covers the origin, evolution, and distribution of life on Earth; how might arise elsewhere in our solar system and beyond; how life adapts to space travel and microgravity; the extreme environments life inhabits on Earth; and how might we detect life elsewhere - and talk with them if we do.

• Astronomy: Covers the formation and evolution of the universe, the formation and distribution of galaxies, stars, solar systems, and planets; the planets and other objects comprise our solar system; and the solar systems and planets that have been detected around other stars.

• Astronautics: All aspects of spacecraft design, construction, operations, navigation, and control. Includes resources on all the humans and other life forms who have flown in space and how robots and automated systems are used to explore space.

• Companies & Commerce Links and resources that cover the companies who launch satellites, build rockets, spacecraft, and components, sell services - and the burgeoning area of space commercialization.

• Computers: Professional and personal software and hardware used to design spacecraft, calculate the positions of the stars and planets, examine data, and handle information about astronomy and space exploration.

• Earth Science: The study of planet Earth: its formation and evolution, atmosphere, surface, and interior - and the way it interacts with the rest of the solar system. Includes global warming, asteroid and comet impacts, and solar-terrestrial interactions.

• Education; The organizations, agencies, and academic institutions that concern themselves with science and technical eduction, specifically those concerned with space exploration and astronomy.

• Exploration & Missions: A collection of resources covering all human and robotic space missions - past, present, and future. Resources include links to official mission websites, images, and scientific results.

• Future Technology: All of the new and exciting technologies that will aid us in the exploration and utilization of space such as advanced propulsion, nanotechnology, solar power satellites, solar sails, space elevators, terraforming, and tethers.

• Government & Politics: Resources covering the various national government agencies and organizations around the world that manage the exploration of space - including their programs, plans, and politics.

• History: Covers the history of astronomy and space exploration including online historial compilations, archives, essays, images, museum websites, memorabilia and collectibles.

• Interactive: Academic resources and commercial sites that deal with virtual reality, webcasts, shared environments, webcams, instant messenging, chat, bulletin boards, and other means whereby people interact with the web, and each other.

• Microgravity Science: Research into understanding the effect of microgravity on basic physical and biological processes and how these phenomena can be used to better understand underlying principles and the possible commercial applications of this novel environment.

• News & Media: Journals, newspapers, magazines, television and radio programs, and Internet resources - scientific and general - that cover astronomy and space exploration.

• Organizations: Scientific, technical, professional, and advocacy organizations involved with space exploration, astronomy, and geophysical sciences.