NASA has started work on a mission called Solar Probe Plus that will plunge deeply into the sun's atmosphere, to shed new light on the giant star's mysteries.
According to a report in Discovery News, though scientists have studied the sun by sending probes to unravel its 11-year cycles, watching its outbursts and measuring how its winds shape the outer edges of the solar system, no spacecraft has been able to enter the its atmosphere as yet.
Now, NASA's Solar Probe Plus will plunge deeply into the sun's atmosphere in an attempt to answer two long-standing questions: Why the sun's outer atmosphere, or corona, is about 2 million degrees Fahrenheit hotter than its surface, and why the solar wind -- streams of electrically charged particles that permeate the solar system -- seems to have no organizing force.
Finding the answers will require a spacecraft that can weather temperatures exceeding 2,550 degrees Fahrenheit and radiation levels higher than any other probe has ever faced.
'Solar Probe Plus will actually enter the corona -- that's where the action is,' said NASA program scientist Lika Guhathakurta.
At closest approach, the spacecraft would be about 4.3 million miles from the sun -- eight times closer than previous probes -- a vantage point that makes the star appear 23 times wider than it does from Earth.
It will be powered by the sun, with liquid-cooled panels that can duck behind a heat shield when the sunlight becomes too intense.
The spacecraft would manoeuvre by flying around Venus seven times in six years to slingshot itself by the planet's gravity deeper and deeper into the sun's atmosphere.
For its finale, Solar Probe Plus should be in position to witness how the sun energizes the most dangerous particles produced in solar storms just at the peak of the sun's stormy season.
Scientists hope to use the information to hone predictions of solar flares and other space weather, which can affect the communications and positioning of satellites around Earth as well as threaten the health of astronauts living outside the bubble of the planet's protective atmosphere.
Solar Probe Plus will have a magnetometer, plasma wave sensor, dust detector, and electron and ion analyzers to measure the environment right around the spacecraft. It will also be equipped with a telescope to make three-dimensional images of the corona.
Scientists hope to time the mission so that it launches in 2015, which would be in the waning years of the present solar cycle, and last through the peak of Solar Cycle 25 so that it can sample the sun's corona and winds during different phases.
