The sun — like a benevolent god, it shines down upon the Earth and sustains all life, and god-like, it has also been beyond the reach of human endeavour. At least until now.
This week, the National Aeronautical and Space Administration (NASA) announced its most ambitious space exploration project yet — to send a probe to our nuclear-powered star by the year 2018.
In developing the path-breaking mission, called Solar Probe Plus, NASA said it was hoping to encounter and study the sun "closer than ever before". The unprecedented project is slated to launch no later than 2018 and will send a small car-sized spacecraft across nearly 150 million kilometres to "plunge directly into the sun’s atmosphere" four million miles above the star’s surface.
The craft would have to withstand temperatures exceeding 2550 degrees Fahrenheit and blasts of intense radiation and to do so, it would be constructed using a revolutionary carbon-composite heat shield.
If the mission succeeds, the spacecraft will have an “up close and personal view of the sun,” NASA said, and it would enable scientists to better understand, characterise and forecast the radiation environment for future space explorers.
Dick Fisher, director of NASA’s Heliophysics Division, said, “The experiments selected for Solar Probe Plus are specifically designed to solve two key questions of solar physics — why is the sun's outer atmosphere so much hotter than the sun’s visible surface and what propels the solar wind that affects Earth and our solar system?" He added that scientists had struggled with such questions for decades and this mission would finally provide answers.
In particular, NASA noted that a mission to provide such measurements was first recommended in 1958 by the National Academy of Science’s “Simpson Committee", and since then NASA had conducted several studies of possible implementations of a Solar Probe mission.
Five science investigations
To make this historic project a reality, NASA said it had selected five science investigations from a 2009 list of proposals that it had called for. The space agency said the total dollar amount for the five selected investigations was approximately $180 million for preliminary analysis, design, development and tests.
Among the selected proposals were studies that proposed to examine particles in solar wind, telescopes designed to make three dimensional images of the sun’s corona, and projects that sought to measure energy fields, radio emissions, and shock waves in the sun’s atmospheric plasma.
An Indian-American scientist on the Solar Probe Plus team, Madhulika Guhathakurta, said, "This project allows humanity's ingenuity to go where no spacecraft has ever gone before... For the very first time, we'll be able to touch, taste and smell our sun."
NASA noted that the Solar Probe Plus mission was part of its "Living with a Star" programme, designed to understand aspects of the sun’s and Earth’s space environment that affected life and society.