The Yohkoh Observatory

The Yohkoh satellite is an orbiting observatory designed to study the hot atmosphere of the Sun (the corona). It does this via the detection of high energy X-ray and gamma-ray radiation.

In particular, the instruments on board Yohkoh were built to detect the very energetic radiation produced in solar flares.

Roughly translated, the Japanese characters at the top of this image say
"Flying High : Yohkoh"

Of the four instruments on Yohkoh the Soft X-ray Telescope (SXT) is the one which tells us most about the dynamic solar atmosphere outside of solar flares. This telescope provides images of the whole Sun every two minutes and images of selected parts of the Sun every 2-32 seconds. The SXT images can be used to study

The Launch of Yohkoh

Yohkoh was launched on 31st August 1991
Yohkoh was launched from the southern tip of Japan's southernmost main island, Kyushu, at the village of Uchinoura on the Ohsumi peninsula.
Yohkoh was launched on an Mu-IIIs-V rocket
Yohkoh is in an Earth orbit with a 31 degree inclination, which
means that during its 97 minute orbit it spends about 30 mins
with the Sun hidden by the Earth. It orbits at a height of
about 600km.

The current location of the Yohkoh spacecraft in its orbit can be found here

Find out how Yohkoh images the Sun
Go back to Solar Explorers page