Bitesize has changed! We're updating subjects as fast as we can. Visit our new site to find Bitesize guides and clips - and tell us what you think!
Print

Science

Planets, stars and galaxies

Page:

  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  1. Back
  2. Next

Little green men

Space probes

6 wheeled vehicle with a big pole on top

NASA Spirit robot vehicle - image courtesy of NASA

Space probes are space craft that can visit other planets without the need for astronauts. Some of the missions undertaken by such craft include:

  • Viking 1 and Viking 2 - landed on Mars in the 1970s, took photographs and analysed soil samples
  • Mars Global Surveyor - went into orbit around Mars in 1997 and mapped the surface in 3D
  • Spirit and Opportunity - two robot vehicles that landed on Mars in 2004
silver telescope with 4 flat panels attached, seen from above, with the earth below

Hubble Space Telescope - image courtesy of NASA

Information about the planets and space can also be obtained using telescopes. These can be based on Earth, or - as with the Hubble Space Telescope - in space.

Watch

You may wish to view this BBC News report from 2005 about the Hubble Space Telescope.

SETI

The Earth's atmosphere contains about 21 per cent oxygen as a result of photosynthesis by plants. If we found evidence of oxygen in the atmosphere of another planet, it could indicate the presence of life forms. It is possible to detect oxygen and other gases on other planets by studying the light reflected between planets.

Watch

You may wish to view this BBC News item from 2006 about how a new type of research radio telescope could pick up TV transmissions from alien civilisations - if they exist.

It is thought possible that alien civilisations, which are capable of transmitting radio signals, may exist. The Search for Extra-Terrestrial Intelligence (SETI) is a programme that uses radio telescopes to look for non-natural signals coming from space. It should be possible to even detect alien TV programmes, if they exist!

Page:

  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  1. Back
  2. Next

Back to Space and its mysteries index

BBC © 2014 The BBC is not responsible for the content of external sites. Read more.

This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.