Venus Express equipment test successful

November 28, 2005
Earth-Moon observations from Venus Express

A recent check of the VIRTIS imaging spectrometer during the Venus Express commissioning phase has allowed its first remote-sensing data to be acquired, using Earth and the Moon as a reference.

Image: Just two weeks after launch, during the commissioning phase of Venus Express, the VIRTIS imaging spectrometer has been able to acquire its first remote-sensing data. This image, acquired on 23 November, shows Earth at about 3.5 million km as seen by VIRTIS-M visible channel in true colour format. The angular separation is about 1.6 degrees. The phase angle is 65 degrees, which means that 65% of Earth's disk is illuminated by the Sun. Credits: ESA/VIRTIS team

After a successful in-flight checkout of the spacecraft's systems in the first ten days of flight, the ESOC operations team is now verifying the health and functioning of all the Venus Express instruments. These observations were made as part of this checkout.
Of course the very large distance that Venus Express has travelled since its launch makes these images of limited interest to the general public, but to the scientific team it confirms the excellent operation of their instrument.

This gives them confidence of spectacular results when the spacecraft reaches Venus where similar measurements will be made hundreds times closer.

VIRTIS sees the Earth-Moon system

Only two weeks after the launch, VIRTIS, the Ultraviolet/Visible/Near-Infrared mapping spectrometer, has been able to make its first planetary observations, capturing the Earth-Moon system.

”The observations were made from 3.5 million kilometres away, with a phase angle of 65 degrees, meaning that 65% of Earth’s disk was illuminated by the Sun, providing observations of both the day and night sides of Earth,” explains Guiseppe Piccioni, one of the two Principal Investigators (PI).

These Earth observations will be used to test the instrument on a real planetary case, before Venus approach.

“A comparison of Venus spectra with Earth spectra with the same instrument will also be of interest for textbook illustration of the comparison between the two planets,” explained Pierre Drossart, the other PI.

The Moon has also been observed, providing additional observations of particular interest for calibrating the instrument.

The VIRTIS instrument on Venus Express is a twin of the same instrument on Rosetta, and similar observations were sent back by Rosetta in March 2005, so comparisons of the two sets of observations will be very useful for calibration purposes.

The VIRTIS instrument is led jointly by INAF-IASF, Rome, Italy, and Observatoire de Paris, France.

Source: ESA

Explore further: What is the weather like on Venus?

Related Stories

What is the weather like on Venus?

December 5, 2016

Venus is often called Earth's "Sister Planet" because of all the things they have in common. They are comparable in size, have similar compositions, and both orbit within the Sun's habitable zone. But beyond that, there are ...

X-rays detected from the dark side of Venus

October 12, 2016

Venus and Mercury have been observed transiting the Sun many times over the past few centuries. When these planets are seen passing between the Sun and the Earth, opportunities exist for some great viewing, not to mention ...

Recommended for you

Samsung to disable Note 7 phones in recall effort

December 9, 2016

Samsung announced Friday it would disable its Galaxy Note 7 smartphones in the US market to force remaining owners to stop using the devices, which were recalled for safety reasons.

0 comments

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.