Space Exploration and Astronauts
The history of our exploration of space goes back to October 4th 1957, when the USSR launched the first ever man-made object into space. The satellite Sputnik, circled the Earth doing little more than send back radio beeps; but it ushered in the space age and started the space race between the USA and USSR and in the process created unbeliveable paranoia in the USA. The USSR went on to launch the first dog into space (Laika in Sputnik II), the first man into space (Yuri Gargarin), and then in 1963 (20 years before Sally Ride) the first woman (Valentina Tereshkova). The space race would ultimately end with the US landing of Apollo 11 on the Moon in June 1969.
Everyone loves to hear about rockets and space-ships. That's what this page is for. Browse the site and email in with your questions.
Human Space flight
The history of human space flight has been dominated by the US and Russian efforts in space and was unquestionably accelerated by the cold-war rivalry between these two countries. Even now, they dominate in the area of human space flight. NASA has an active core of Astronauts that number many tens, and at The Yuri Gagarin Cosmonauts Training Centre in Russia cosmonauts are in active training (when they are not in space). Other countries are involved in human exploration of space to lesser extents. ESA has a human space flight division with a 16 person Astronaut Corps. Japan and Canada are also involved; each have had at least one Astronaut fly with NASA. China joined the list of nations who have independently launched people into space on Oct 15 2003 when they sucessfully launched their first Taikonaut (from the Chinese word taikong, meaning space).
Here is a list of some of the more famous human space programs (in rough chronological order):
- Vostok: the Russian space craft that put the first person into space.
- Soyuz: the longest serving spacecraft in the world.
- Mercury: this was the first American program to put men into space.
- Gemini: the second US manned spaceflight program.
- Apollo: this of course, was the program which put Americans onto the Moon.
- Mir: the Russian space station that orbited the Earth for 11 years! "Mir" is the word for "peace" in Russian.
- Skylab: basically what it sounds like, this was a lab in space. Not quite a space station, this was NASA's first step in that direction.
- The Shuttle: designed to shuttle people to a space station, it was in operation for almost 20 years before it visited Mir and acheieved that goal. With the end of Mir it can now also visit the ISS. The shuttle has proved its use countless times, delivering satellites into space and helping people to fix the Hubble Space Telescope (among other things).
- The International Space Station
- Shenzhou: the series of missions which saw China become the 3rd nation into space.
The explosion of the Columbia orbiter on its return to Earth on February 1st 2003 was a tragedy no one was expecting. It has thrown the Shuttle program into review and led to the postponement of all Shuttle flights indefinitely. The International Space Station is surviving on a limited crew, which are transferred by Soyuz crafts from Russia. What ramifications this accident will have on human spaceflight as a whole remain to be seen. On January 14th 2004, U.S. President George Bush called for the Shuttle program to be eliminated by 2010 and replaced by a yet-to-be-specified "Crew Exploration Vehicle," which would return astronauts to the Moon by 2020 and eventually lead to the construction of a lunar base and a manned mission to Mars.
Non-human Space Flight
Many people would argue than human spaceflight saps money from the programs that are really doing science in space. Whatever is your opinion on that, a lot of very exciting stuff is happening in non-human spaceflight.
Satellites around the Earth
Many satellites are in orbit around the Earth. Some of them are used to study the Earth, others to study other objects of interest in Astronomy. Most of the satellites are there for commercial or military uses. You may very well have a dish on your house to pick up TV signals broadcast from a satellite, or be looking at this website via a satellite relay!
If you stare into the night sky for long enough you might notice some funny star-like objects which move quite regularly across the sky. Most likely what you are looking at is an artificial satellite shining by reflected sunlight. If you want to be more active in searching for satellites you can use Heavens-Above, a website which will tell you what satellites (and other objects) you can see in the sky above you.
One of the most famous satellites in orbit today is the Hubble Space Telescope. A famous historical satellite is Sputnik (the first human-made object in space).
Missions to other objects in our Solar System
So far spacecraft have visited every major planet in our solar system (with the possible exception of Pluto depending on how you want to classify it). We have also visited more than one comet and asteroid. Below is an incomplete summary of the main missions sorted by object.
- Mercury: The spacecraft Mariner 10 flew by Mercury three times in 1974/75. NASA is planning a Mercury orbiter, Messenger, to arrive in 2009.
- Venus: Venus's thick atmosphere make observations of the surface difficult. It also heats up the planet to the temperature of molten lead. Unsurprisingly then the only lander (Venera 13 in 1982) didn't last very long. Venus has had a lot of visitors though, perhaps the most famous being Magellan (in the early 1990s).
- Mars: Mars is perhaps the most visited planet, having had three landers (Viking 1 and 2 and Pathfinder) as well as a fleet of orbiting spacecraft (see here for a list). Mars's close opposition in 2003 has led to a fleet of spacecraft being sent, including Mars Express (with the Beagle 2 lander) from ESA, and two rovers (Spirit and Opportunity) from NASA.
- Jupiter: The NASA missions Pioneers 10 and 11 passed by Jupiter, as did both Voyagers. The famous Galileo mission arrived at Jupiter in 1995 after a six year journey, returning images until its scheduled crash into the planet in September 2003.
- Saturn: The spacecraft Pioneer 11 and both Voyager missions flew by Saturn. Saturn is also due to have its own special visitor with the arrival of the Cassini/Huygens spacecraft expected for 2004.
- Uranus: Voyager 2 flew by Uranus in 1986.
- Neptune: Voyager 2 flew by Neptune in 1989.
- Pluto: Pluto is the only major object in our solar system not to have had a spacecraft visit it. "New Horizons" is a planned mission to both Pluto and some Kuiper belt objects.
- Asteroids: The NEAR (Near-Earth Asteroid Rendezvous) mission to Eros is perhaps the most famous mission to an asteroid; the spacecraft actually "landed" on the asteroid on February 14th 2001. Galileo also passed by some asteroids (Gaspra, Ida and Mathilde) on its way to Jupiter.
- Comets: When Halley's Comet passed near the Earth in 1986, a fleet of spacecraft was sent to intecept it.
The Ask an Astronomer team's favorite links about Space Exploration and Astronauts:
- NASA: National Aeronautics and Space Administration
- NASA Watch. Not a NASA site, but a way to keep up with what NASA is up to.
- Russian Federal Space Agency: not very much is in English, but I thought I should include this for completeness.
- ESA: European Space Agency
- Spaceflight Now: claims to be "the leading source for online space news."
- Solar System Exploration Home Page: a site run by the NASA Jet Propulsion Lab (JPL). Very complete listings of all missions (past, present and future, and not just NASA missions) to solar system objects.
- NASA TV: Want to watch the astronauts in orbit? This is the place to find out how you can do that.
Previously asked questions about Space Exploration and Astronauts:
General questions:
- Can you hear sounds in space? (Beginner)
- How do we weigh objects in space? (Beginner)
- What is the farthest in space that we have gone? (Beginner)
- Do constellations looks the same from space? (Beginner)
- Does weightlessness affect hunger? (Beginner)
- What would happen if a nuclear-powered shuttle exploded? (Beginner)
- Is it sensible to consider terraforming Mars? (Beginner)
- Can artificial gravity be created in space? (Intermediate)
- Why do photos of space taken from space never show any stars? (Intermediate)
- What are some of the effects of solar flares on Earth? (Intermediate)
- Why do spacecraft need heat shields coming back to Earth but not leaving? (Intermediate)
- How fast do particles travel in space? (Intermediate)
- What kinds of cancer research have been done in space? (Intermediate)
- Why doesn't NASA build rotating spacecraft to simulate gravity? (Intermediate)
- How much money is spent on space exploration? (Intermediate)
- Can we harvest H & O from space to make water? (Intermediate)
- What would happen if a human were exposed to space without wearing a spacesuit? (Intermediate)
Human Spaceflight (current or past):
- Does the shuttle worry about space junk? (Beginner)
- What would happen if you took off your helmet in space? (Beginner)
- What do astronauts eat in space? Can they grow food? (Beginner)
- How do astronauts use math in their jobs? (Beginner)
- Why hasn't NASA gone back to the moon? (Beginner)
- Why do astronauts in space need to exercise? (Beginner)
- How do astronauts take baths and use restrooms in space? (Beginner)
- Can astronauts play musical instruments in space? (Beginner)
- Why do humans want to go in space? (Beginner)
- How many Astronauts have been in space? (Beginner)
- Does weightlessness affect hunger? (Beginner)
- How do astronauts communicate with their families from space? (Beginner)
- How do the astronauts communicate in space if sound cannot travel in a vacuum? (Beginner)
- Why was Mir burnt up in the atmosphere? (Intermediate)
- Can astronauts produce water in space? (Intermediate)
- How do I become both an astronaut and an astronomer? (Intermediate)
- How are astronauts trained for weightlessness? (Intermediate)
- Can the Space Shuttle abort and return to Earth before reaching orbit? (Intermediate)
- Will astronauts ever be able to go ice-skating on Europa? (Intermediate)
- What do astronauts do all day in the International Space Station? (Intermediate)
- How much money is spent on space exploration? (Intermediate)
- What would happen if a human were exposed to space without wearing a spacesuit? (Intermediate)
- When will humans travel to Mars and revisit the Moon? (Intermediate)
- Why don't astronauts sublimate in space? (Advanced)
- What color would Mars be if you were standing on it? (Advanced)
Rockets:
- How do rockets move in space? (Beginner)
- What can I use for fuel in my homemade rocket? (Beginner)
- What would happen if a nuclear-powered shuttle exploded? (Beginner)
- How do I build a model rocket? (Intermediate)
- How do rockets work? (Intermediate)
- How does the parachute in a model rocket work? (Advanced)
The Future of Human Spaceflight:
- If we invented special suits could we ever go to the sun? (Beginner)
- Why hasn't NASA gone back to the moon? (Beginner)
- Can we colonize other planets? (Beginner)
- Could someone travel the universe in his or her own lifetime? (Beginner)
- What would happen if a nuclear-powered shuttle exploded? (Beginner)
- Could we send a manned mission to the outer planets? (Intermediate)
- Will astronauts ever be able to go ice-skating on Europa? (Intermediate)
- Is there oxygen in the atmospheres of other planets? (Intermediate)
- Can a human give birth in space? (Intermediate)
- What would happen if a human were exposed to space without wearing a spacesuit? (Intermediate)
- When will humans travel to Mars and revisit the Moon? (Intermediate)
The Moon Landings:
- Did astronauts really go to the Moon, or is it a hoax? (Beginner)
- Why hasn't NASA gone back to the moon? (Beginner)
- Who has landed on the moon? (Beginner)
Aeronautics:
- Why do airplanes take longer to fly West than East? (Intermediate)
- Why doesn't NASA build rotating spacecraft to simulate gravity? (Intermediate)
Satellites/robotic space craft:
- Can you see satellites? (Beginner)
- Could we send a space mission to a comet? (Beginner)
- Why is the Hubble Space Telescope in space? (Beginner)
- How do unmanned space probes avoid running into things? (Beginner)
- Why is NASA shutting down the Hubble Space Telescope? (Beginner)
- When unmanned spacecraft accelerate in space, what causes them to slow down? (Intermediate)
- What makes a satellite geosyncronise itself with Earth's orbit? (Intermediate)
- What are the advantages and disadvantages of using a telescope in space? (Intermediate)
- Do unmanned spacecraft like Voyager travel in straight lines? (Intermediate)
- Why did the Pioneer and Voyager take only 2 years to reach Jupiter, while Galileo and Cassini took more than 5 years? (Intermediate)
- How big is the Hubble Ultra Deep Field image? (Intermediate)
How to ask a question:
If you have a question about Space Exploration and Astronauts which isn't answered above, submit it here. If you have a question about another area of astronomy, find the topic you're interested in from the archive on our site menu, or go here for help.
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