Europe's Venus Express Probe Looks Back at Earth

Europe's Venus Express Probe Looks Back at Earth
Venus Express took this thermal view of Earth during an infrared observation with its VIRTIS instrument. The planet appears almost 'fully illuminated' with no difference from day and night regions since only the thermal radiance is seen. The Antarctica region, being colder, generates a weaker signal. (Image credit: ESA/VIRTIS Team.)

A Europeanprobe bound for Venus has taken a parting glance at its home world as it headstoward its cloudy quarry.

TheEuropean Space Agency's (ESA) Venus Express probe photographed Earth and the Moonin both visible and infrared light during a shakedown of its instrumentpackage, which includes the VIRTIS imaging spectrometer.

"It showsthat the instrument is really working beautifully," Kevin Baines, a NASAparticipating scientist with Venus Express' VIRTIS team, told"It bodes well for the rest of the mission."

VIRTIS, an instrumentthat scans objects in the ultraviolet, visible and near-infrared range of thelight spectrum, is designed to track Venus' thick clouds at varying altitudes,as well as study their composition. Like many of the instruments aboard VenusExpress, VIRTIS is similar to a tool flown on a previous ESA mission - in thiscase the comet-bound Rosettaprobe.

When pointedat Earth, VIRTIS returned a familiar globe of blue and white - with day andnight sides easily discernable - in the visible range, while an infrared viewpresented a thermal glimpse of a planet awash in warm reds. The observationswill serve as a benchmark for comparison once the spacecraft reaches Venus, ESAresearchers said.

"Acomparison of Venus spectra with Earth spectra with the same instrument willalso be of interest for textbook illustration of the comparison between the twoplanets," said Pierre Drossart, one of two principal investigators for theVIRTIS instrument, in a statement.

VenusExpress turned its VIRTIS eye on the Earth-Moon system from a distance of about2.1 million miles (3.5 million kilometers).

The probe'ssix other primary instruments, such as its Venus Monitoring Camera, are alsogoing through their own series of checks and evaluations.

"It's liketesting a new airplane or car," Baines said. "Before you go off joyriding withit, you want to make sure everything works."

VenusExpress launchedspaceward late Nov. 8 EST from Kazakhstan's Baikonur Cosmodrome and is expectedto reach Venus in April 2006.

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Tariq Malik

Tariq is the Editor-in-Chief of and joined the team in 2001, first as an intern and staff writer, and later as an editor. He covers human spaceflight, exploration and space science, as well as skywatching and entertainment. He became's Managing Editor in 2009 and Editor-in-Chief in 2019. Before joining, Tariq was a staff reporter for The Los Angeles Times covering education and city beats in La Habra, Fullerton and Huntington Beach. In October 2022, Tariq received the Harry Kolcum Award for excellence in space reporting from the National Space Club Florida Committee. He is also an Eagle Scout (yes, he has the Space Exploration merit badge) and went to Space Camp four times as a kid and a fifth time as an adult. He has journalism degrees from the University of Southern California and New York University. You can find Tariq at and as the co-host to the This Week In Space podcast with space historian Rod Pyle on the TWiT network. To see his latest project, you can follow Tariq on Twitter @tariqjmalik.