A probe circling the planet Venus has slipped into its final orbit around the cloud-covered world, though final instrument checks are still underway, the European Space Agency (ESA) said Tuesday.
The space agency's Venus Express spacecraft, which arrived around its target planet last month, settled into its final, elliptical orbit Sunday, ESA officials said. The orbital path ranges between 155 miles (250 kilometers) and 41,010 miles (66,000 kilometers) above the cloudy world's surface and takes 24 hours for a complete circuit, they added.
"This is the orbit designed to perform the best possible observations of Venus, given the scientific objectives of the mission," said H?kan Svedhem, Venus Express project scientist for the ESA, in a statement.
When Venus Express first entered orbit around its destination world, the probe's orbit varied in altitude between 248 miles (400 kilometers) and 217,479 miles (350,000 kilometers). Despite the large distance to Venus at its farthest point, that initial, nine-day orbit excited researchers since it gave them their only global views of Venus for the planned 243-Earth day mission.
Two days after making orbital arrival, Venus Express returned images of its target planet's south pole - the first-ever of Venus - finding a previously suspected vortex that appears to be a counterpart to a north pole structure.
The $226 million (220 million Euro) Venus Express mission launched from Earth in November 2005 as the ESA's fastest-developed expedition to date. It is the first dedicated orbiter to visit the planet since NASA's Magellan probe, which ended its mission with a death plunge into the Venusian atmosphere in 1994.
Checks of the Venus Express' seven primary instruments will continue until about June 4, when the spacecraft's science phase is slated to begin, mission managers said.