WASHINGTON (dpa-AFX) - US space agency Nasa has launched its mission to send a satellite closer to the Sun than any before.
The Parker Solar Probe rocket lifted off from Cape Canaveral, Florida.
The probe is set to become the fastest-moving manmade object in history. Its data promises to crack longstanding mysteries about the Sun's behaviour.
It is the first space craft to be named after a living person - astrophysicist Eugene Parker, 91, who first described solar wind in 1958.
The Delta-IV Heavy rocket - which was carrying the probe - launched at 03:31 local time (07:31 GMT).
It came after a failed attempt the previous day, when a last-minute alarm caused the agency to miss its 65-minute weather window.
The probe aims to dip directly into our star's outer atmosphere, or corona.
It is travelling on board the Delta-IV Heavy rocket, which will hurl the probe into the inner Solar System.
The probe will zip past Venus in six weeks and make a first rendezvous with the Sun a further six weeks after that.
In order to reach an orbit around the sun, the Parker Solar Probe will take seven flybys of Venus that will essentially give a gravity assist, shrinking its orbit over the course of nearly seven years.
The probe will orbit within 3.9 million miles of the sun's surface in 2024, closer to the star than Mercury. Although that sounds far, researchers equate this to the probe sitting on the 4-yard line of a football field and the sun being the end zone. When closest to the sun, the 41/2-inch-thick carbon-composite solar shields will have to withstand temperatures close to 2,500 degrees Fahrenheit. However, the inside of the spacecraft and its instruments will remain at a comfortable room temperature.
The probe will reach a speed of 430,000 miles per hour around the sun, setting a record for the fastest manmade object. On Earth, this speed would enable someone to get from Philadelphia to Washington in one second, the agency said.
Copyright RTT News/dpa-AFX