SOHO watches Saturn and Cassini pass behind Sun (Forwarded)

ESA News
http://www.esa.int

27 July 2005

SOHO watches Saturn and Cassini pass behind Sun

In this SOHO image, taken 21 July 2005, the Sun is represented by the
white circle in the centre. Saturn is the bright object to the left of
the Sun.

Saturn was approaching a position called 'superior conjunction', that
is, it would be almost directly behind the Sun as seen from Earth.
Therefore the NASA/ESA/ASI Cassini spacecraft, in orbit around Saturn,
was not able to send or receive transmissions normally.

As Cassini passed close by the limb (edge) of the Sun on 24 July,
communications became impossible because of the Sun's radio noise. The
spacecraft regained full communication with Earth on 27 July, once again
returning Saturn science data.

In the meantime, Cassini radio scientists are taking advantage of this
opportunity to study the Sun's corona from its effects on the radio
signals that reach Earth. This is a joint co-ordinated observation
involving two SOHO instruments (UVCS and LASCO), plus Cassini and some
ground-based radio sites.

Interestingly, the bright 'streak' accompanying Saturn is not the rings
but a result of 'pixel bleeding'.

SOHO, the ESA/NASA Solar and Heliospheric Observatory, orbits the Sun
parked in one of the five gravitationally neutral spots, called
'Lagrange points'. This specific spot, called L1, stays in the same
place relative to the Sun and Earth, offering SOHO a continuously
uninterrupted view of the Sun.

For more information:

Bernhard Fleck, ESA SOHO Project Scientist
E-mail: bfleck @ esa.nascom.nasa.gov

More about...

* At Saturn and Titan
http://www.esa.int/SPECIALS/Cassini-Huygens/index.html
* SOHO overview
http://www.esa.int/esaSC/120373_index_0_m.html

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IMAGE CAPTION:
[http://www.esa.int/esaCP/SEM3IE808BE_index_1.html]
This SOHO image was taken on 21 July 2005. The Sun is represented by the
white circle in the centre. Saturn is the bright object to the left of
the Sun.

Credits: ESA/NASA