New Venus Probe to Launch Thursday From Japan After Delay

A Japanese mission to launch a powerful orbiter to Venusalong with a separate solar sail vehicle is now targeted for a Thursday launch (U.S.time) after freezing conditions and clouds thwarted a Monday liftoff attempt.

The new VenusClimate Orbiter Akatsuki isnow set to launch atop an unmanned H-2A rocket from Japan's Tanegashima SpaceCenter on Thursday at 5:58 p.m. EDT (2158 GMT). Because of time zonedifferences, it will be 6:58 a.m. (local time) on Friday, May 21 at theJapanese launch site when the new mission blasts off.

Officials with the Japan Aerospace Exploration Agency(JAXA) said that "adverse weather conditions" forced them to call offthe first attempt to launch the Akatsuki orbiter toward Venus. Weather forecasts apparentlypredicted dismal conditions for much of the rest of week as well, promptingseveral days of delays.

"After studying weather conditions from tomorrow, wedecided to carry out the launch at 6:58:22 a.m. on May 21, 2010 (Japan StandardTime, JST) because the weather is expected to recover in that timeframe,"JAXA officials said in a statement.

Japan's Akatsuki orbiteris expected to study Venus in unprecedented detail to unravel enduringmysteries of the planet's hellishatmosphere and surface. The spacecraft is due to arrive at Venus inDecember and spend two years studying the planet.

But Akatsuki is not launching intospace alone.

The probe carries several smaller satellite experimentsalong with IKAROS, a solarsail spacecraft that will tag along with Akatsuki on the way to Venus. If all goes well, theIKAROS would be the first interplanetary solar sail craft and just a pit stopat Venus before heading? toward a region over the far side of the sun, JAXAofficials have said.

Akatsuki and IKAROS would join aEuropean spacecraft already in orbit around Venus when they arrive.

The European Space Agency's Venus Express orbiter hasbeen studying Venus since it arrived at the planet in 2006. Venus Express and Akatsuki are expected to complement each other intheir observations of the second planet from the sun, scientists with bothmissions have said.

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