STEREO (Solar TErrestrial RElations Observatory) is a solar observation mission to be launched no earlier than August 1 2006. Two identical spacecraft will be launched into orbits that cause them to (respectively) pull further ahead and fall gradually behind the earth. This will enable stereoscopic imaging of the Sun and solar phenomena, such as Coronal Mass Ejections.

Mission profile

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On November 9 2005 both spacecraft were shipped from Johns Hopkins University Applied Physics Laboratory to Goddard Space Flight Center, in preparation for launch. As of May 3, 2006, the twin spacecraft are undergoing final pre-launch tests and preparations at the Astrotech Spacecraft Processing Facility in Florida. The Delta II rocket destined to carry the STEREO spacecraft into orbit is being assembled at Launch Complex 17. The STEREO spacecraft are scheduled to be mated to the Delta II on July 10, 2006.

They will be launched into a highly elliptical geocentric orbits in mid 2006, with an apogee at approximately the distance of the Moon. Two months afterwards (on the fifth orbit) the pair swing by the moon for a gravitational slingshot. This slingshot will maneuver the behind spacecraft (designated "B") to a heliocentric orbit outside Earth's orbit. The ahead spacecraft ("A") will encounter the moon again on the same orbital revolution, placing it into a heliocentric orbit inside the Earth's. Spacecraft A will take 347 days to complete one revolution of the sun, with Spacecraft B taking 387 days. They will retreat from the earth by about 22° per earth year.

Instrumentation

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The spacecraft will carry cameras, particle experiments and radio detectors in four instrument packages:

• Sun Earth Connection Coronal and Heliospheric Investigation (SECCHI) - SECCHI has four instruments: an extreme ultraviolet imager, two white-light coronagraphs and a heliospheric imager. The purpose of SECCHI is to study the 3-D evolution of Coronal Mass Ejections through their full journey from the Sun's surface through the corona and interplanetary medium to their impact at Earth.
• In-situ Measurements of Particles and CME Transients (IMPACT) - IMPACT will study energy particles and magnetic fields of the Sun.
• PLAsma and SupraThermal Ion Composition (PLASTIC) - PLASTIC will study the plasma characteristics of protons, alpha particles and heavy ions.
• STEREO/WAVES (SWAVES) - SWAVES is a radio burst tracker that will study radio disturbances traveling from the Sun to the orbit of Earth.

See also

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• SOHO, solar observatory launched in 1995, still operational.
• Ulysses probe, 1990 mission

References

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External links

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• STEREO, official site
• STEREO, NASA version

NASA | Solar missions | Space telescopes

STEREO | STEREO | STEREO | STEREO (sondy)