CSIRO telescopes help rescue Titan experiment

February 15, 2005

CSIRO’s radio telescopes and others in Australia, China, Japan and the USA have revealed how the wind speeds on Saturn’s moon Titan vary with altitude-and have turned a disappointment into a triumph.

As the Huygens probe plummeted through Titan’s atmosphere on 14 January it transmitted a stream of data to its parent Cassini spacecraft. The ground-based radio telescopes ’eavesdropped’ on the probe’s signal. As the probe was buffeted by Titan’s winds, its radio signal was shifted in frequency. These ’Doppler shifts’ have been used to measure the wind speeds.

Another experiment to determine the Doppler shifts, the Cassini/Huygens Doppler Wind Experiment, was going to rely on data transmitted from the probe to Cassini. But the transmitted data was lost because because one of the receivers on Cassini was not properly configured. The data from the telescopes has plugged that gap.

The largest telescopes involved were the NRAO Robert C. Byrd Green Bank Telescope in the USA and CSIRO’s Parkes Radio Telescope in Australia. Thanks to special instruments borrowed from NASA, these telescopes were the first to directly ’see’ the probe’s signal.

The wind on Titan has been found to flow in the direction of Titan’s rotation-west to east-at nearly all altitudes. The winds are weak near the surface and increase slowly with altitude up to about 60 km. The maximum speed of about 430 km/hour was found at an altitude of 120 km. Above 60 km there are large variations in the Doppler measurements, which scientists think were caused by vertical wind shear.

The radio telescope network was coordinated by the Joint Institute for VLBI in Europe, JIVE, and NASA’s Jet Propulsion Laboratory, JPL. JPL and JIVE also made and processed the ground-based Doppler measurements, working with the Doppler Wind Experiment team.

Explore further: First measurement of Titan’s winds from Huygens

Related Stories

First measurement of Titan’s winds from Huygens

February 9, 2005

Using a global network of radio telescopes, scientists have measured the speed of the winds faced by Huygens during its descent through the atmosphere of Titan. This measurement could not be done from space because of a configuration ...

Radio Telescopes to Keep Sharp Eye on Mars Lander

May 23, 2008

As NASA's Phoenix Mars Lander descends through the Red Planet's atmosphere toward its landing on May 25, its progress will be scrutinized by radio telescopes from the National Radio Astronomy Observatory (NRAO). At NRAO control ...

Solar Wind Originates in Coronal Funnels

April 22, 2005

The ESA/NASA SOHO spacecraft determines the origin of the fast solar wind in the magnetized atmosphere of the Sun A Chinese-German team of scientists have identified the magnetic structures in the solar corona where the ...

In Depth: Rain, winds and haze during the descent to Titan

November 30, 2005

The high-resolution images taken in Titan's atmosphere by the Descent Imager/Spectral Radiometer (DISR) were spectacular, but not the only surprises obtained during descent. Both DISR and the Doppler Wind Experiment data ...

90 million laser shots bring wind satellite back on track

April 18, 2013

(Phys.org) —Developing new ways of monitoring Earth is always demanding, but ESA's Aeolus mission has faced some particularly difficult technical challenges. However, with the success of intense high-energy tests on its ...

Recommended for you

New analysis of big data sheds light on cell functions

October 26, 2016

Researchers have developed a new way of obtaining useful information from big data in biology to better understand—and predict—what goes on inside a cell. Using genome-scale models, researchers were able to integrate ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.