As the Juno spacecraft zooms towards Jupiter at 200 times the speed of sound, NASA scientists on earth are nervously hoping it hits the brakes at just the right time to get pulled into Jupiter’s orbit.
As the Juno spacecraft zooms towards Jupiter at 200 times the speed of sound NASA scientist on earth are nervously hoping it hits the breaks at just the right time to get pulled into Jupiter’s orbit.
The moment of truth is expected at about 12 midnight EDT (04:00 GMT/UTC) on Tuesday), according to Juno’s principal investigator Scott Bolton, at the Southwest Research Institute in San Antonio, Texas.
“We are barreling down on Jupiter really quick,” Bolton said.
As NASA counted down to Juno’s arrival, Bolton admitted to being “nervous” and “scared” about the fate of the $1.1 billion (1 billion euro) spacecraft, which is traveling at a speed of more than 150,000 miles per hour (250,000 kmph) toward what he called “the king of the solar system.”
The plan is for Juno to slow down in order to be captured by Jupiter’s gravity and pulled into its orbit 3,000 miles (5,000 kilometers) above the clouds. For that to happen Juno must be precisely positioned, ignite its main engine at exactly the right moment and keep it burning for 35 minutes to lose enough speed.
There is also the obstacle course of debris it must pass through, where even a piece of dust could doom it.
Throughout its 37 orbits, over 20 months, Juno’s titanium cover must endure massive amounts of radiation – the equivalent of 100 million dental x-rays.
Ultimately a suicide mission
Juno’s aim is to map Jupiter’s gravity and magnetic fields and determine. For its grand finale – its final orbit – Juno will dive into Jupiter’s atmosphere, where it will be crushed and vaporized.
Among the questions scientists Juno will help answer are: How much water exists? Is there a solid core? Why are Jupiter’s southern and northern lights the brightest in the solar system?
“What Juno’s about is looking beneath that surface,” Bolton said. “We’ve got to go down and look at what’s inside, see how it’s built, how deep these features go, learn about its real secrets.”
There’s also the mystery of its Great Red Spot, which appears to be a massive, centuries old, storm – larger than the earth.
Juno is the first spacecraft to travel so far out powered by the sun, beating Europe’s comet-chasing Rosetta spacecraft. Three massive solar wings stick out from Juno like blades from a windmill. They house 18,698 solar cells, which generate 500 watts of power to run its nine instruments.
Jupiter’s sheer size gives it immense gravity, which it exerts by packing 21/2 times the mass of all the other planets in our solar system combined.
Its mass and gravitational force is believed to have helped shield Earth from bombardment of comets and asteroids – an astronomical lightning rod, so to speak.
bik/xx (AP, Reuters, AFP)