Jupiter is the fifth planet from the Sun, and the largest. It is more than
twice the size of all the other planets put together.
Jupiter is 778 330 000 km from the Sun and is
318 times larger than the Earth.
There are 4332.71 days in a Jupiter year.
Jupiter is known as a gas planet, made up of about
90% hydrogen, 10% helium and a few trace
elements, including sulphur. When we view Jupiter,
what we see are the tops of clouds high in the atmosphere. The winds blow
in opposite directions
in bands next to each other,while slight variations in temperature and chemicals
give the bands their differences in colour. The light coloured bands are called
Zones and the dark bands are called Belts.
One of Jupiters most visible features is the
Great Red Spot.
It is an oval storm about 12 000 km by 25 000 km
big enough to hold two Earths. The GRS, as it is more commonly known, is visible from Earth with a small astronomical telescope.
The first spacecraft to visit Jupiter was
Pioneer 10 launched on
March 2 1972 from Cape Kennedy, followed by its sister craft
Pioneer 11. Pioneer 10's main priority was to see if a probe could pass through
the solar systems asteroid belt, and Jupiters
enormous magnetic field. With great success it reached Jupiter
in 1973 and became the first spacecraft to make direct observations and take
close up images of the planet.
and is now heading towards Aquila (The Eagle), northwest of Sagittarius.
Pioneer 11 should reach there in about 4 million years time.
The Voyager 1 space probe was launched on Sept 5 1977 and
flew past Jupiter
on March 5 1979. Voyager 2 was launched on Aug 20 1977, before voyager 1,
and flew past Jupiter on Aug 7 1979. Between the two probes, it was discovered
that Jupiter had rings like Saturn, though not as prominent. It was also
discovered that Io had very active sulfurous volcanoes.
Galileo is the most recent and ongoing
mission around Jupiter 
Galileo was launched from the space
shuttle on Oct 18 1989. It flew past Venus on Feb 9 1990, back to Earth
on Dec 8 1990 and out to the asteroid belt passage between July 1991 - June
1992.
It returned to Earth on Dec 8 1992 and back out to the asteroid belt between
May 1993 - Nov 1993.
The probe seperated on July 13 1995 and reached Jupiter on Dec 7 1995. Data
returned by the probe, which descended around 150 km below the cloud tops,
indicated that the winds force is more than 400 mph and extends down at
least as far as the probe went. The probe also observed that Jupiters atmosphere
is very turbulent, which indicates the winds are probably driven more by
the internal heat of the planet rather than from solar input like we observe
here on Earth.
DISTANCE from Jup/km
128 000
129 000
181 000
222 000
422 000
671 000
1 070 000
1 883 000
7 400 000
11 094 000
11 480 000
11 720 000
11 737 000
21 200 000
22 600 000
23 500 000
23 700 000
DISCOVERER
SYNNOTT
JEWITT
BARNARD
SYNNOTT
GALILEO
GALILEO
GALILEO
GALILEO
SPACEWATCH
KOWAL
PERRINE
NICHOLSON
PERRINE
NICHOLSON
NICHOLSON
MELOTTE
NICHOLSON
DATE
1979
1979
1892
1979
1610
1610
1610
1610
1999
1974
1904
1938
1905
1951
1938
1908
1914
