NASA will host a two-day launch Tweetup for 150 of its Twitter followers on Aug. 4-5 at the agency's Kennedy Space Center in Florida. The Tweetup is expected to culminate in the launch of the Jupiter-bound Juno spacecraft aboard an Atlas V rocket.

The launch window opens at 8:39 a.m. PDT (11:39 a.m. EDT) on Aug. 5. The spacecraft is expected to arrive at Jupiter in 2016. The mission will investigate the gas giant's origins, structure, atmosphere and magnetosphere. Juno's color camera will provide close-up images of Jupiter, including the first detailed glimpse of the planet's poles.

The Tweetup will provide @NASA Twitter followers with the opportunity to tour the Kennedy Space Center Visitor Complex; speak with scientists and engineers from the Juno and other upcoming missions; and, if all goes as scheduled, view the spacecraft launch. The event also will provide participants the opportunity to meet fellow tweeps and members of NASA's social media team.

Juno is the second of four space missions launching this year, making 2011 one of the busiest ever in planetary exploration. Aquarius was launched June 10 to study ocean salinity; Grail will launch Sept. 8 to study the moon's gravity field; and the Mars Science Laboratory/Curiosity rover will head to the Red Planet no earlier than Nov. 25.

Tweetup registration opens at noon PDT (3 p.m. EDT) on Friday, June 24, and closes at noon PDT (3 p.m. EDT) on Monday, June 27. NASA will randomly select 150 participants from online registrations. For more information about the Tweetup and registration, visit: http://www.nasa.gov/connect/tweetup/tweetup_jpl_08-04-2011.html .

For information about connecting and collaborating with NASA, visit: http://www.nasa.gov/connect .

Juno's principal investigator is Scott Bolton of the Southwest Research Institute in San Antonio. NASA's Jet Propulsion Laboratory in Pasadena, Calif., manages the mission.