TAMPA – NASA counted down Friday to the launch of a $1.5 billionspacecraft that aims to plunge into the Sun s sizzling atmosphere andbecome humanity s first mission to explore a star.
The car-sized Parker Solar Probe is scheduled to blast off on a Delta IVHeavy rocket from Cape Canaveral, Florida early Saturday.
The 65-minute launch window opens at 3:33 am (0733 GMT), and the weatherforecast is 70 percent favorable for takeoff, NASA said.
The probe s main goal is to unveil the secrets of the corona, the unusualatmosphere around Sun.
Not only is the corona about 300 times hotter than the Sun s surface, italso hurls powerful plasma and energetic particles that can unleashgeomagnetic space storms and disrupt Earth s power grid.
“The Parker Solar Probe will help us do a much better job of predictingwhen a disturbance in the solar wind could hit Earth,” said Justin Kasper,one of the project scientists and a professor at the University of Michigan.——————————
*Full of mysteries*——————————
The probe is protected by an ultra-powerful heat shield that is just 4.5inches thick (11.43 centimeters).
The shield should enable the spacecraft to survive its close shave with thecenter of our solar system, coming within 3.83 million miles (6.16 millionkilometers) of the Sun s surface.
The heat shield is built to withstand radiation equivalent up to about 500times the Sun s radiation here on Earth.
Even in a region where temperatures can reach more than a million degreesFahrenheit, the sunlight is expected to heat the shield to just around2,500 degrees Fahrenheit (1,371 degrees Celsius).
Scorching, yes? But if all works as planned, the inside of the spacecraftshould stay a cooler 85 F (29 C).
The goal for the Parker Solar Probe is to make 24 passes through the coronaduring its seven-year mission.
“The sun is full of mysteries,” said Nicky Fox, project scientist at theJohns Hopkins University Applied Physics Lab.
“We are ready. We have the perfect payload. We know the questions we wantto answer.”- 91-year-old namesake –
The tools on board will measure the expanding corona and continuallyflowing atmosphere known as the solar wind, which solar physicist EugeneParker first described back in 1958.
Parker, now 91, recalled that at first, some people did not believe in histheory.
But then, the launch of NASA s Mariner 2 spacecraft in 1962 — becoming thefirst robotic spacecraft to make a successful planetary encounter — provedthem wrong.
“It was just a matter of sitting out the deniers for four years until theVenus Mariner 2 spacecraft showed that, by golly, there was a solar wind,”Parker said earlier this week.
He added that he is “impressed” by the Parker Solar Probe, calling it “avery complex machine.”
Scientists have wanted to build a spacecraft like this for more than 60years, but only in recent years did the heat shield technology advanceenough to be capable of protecting sensitive instruments, according to Fox.
Tools on board will measure high energy particles associated with flaresand coronal mass ejections, as well as the changing magnetic field aroundthe Sun.
“We will also be listening for plasma waves that we know flow around whenparticles move,” Fox added.
“And last but not least, we have a white light imager that is taking imagesof the atmosphere right in front of the Sun.”
When it nears the Sun, the probe will travel rapidly enough to go from NewYork to Tokyo in one minute — some 430,000 miles (700,000 kilometers) perhour, making it the fastest human-made object. – APP/AFP