Nasa’s Parker Solar Probe takes off for tryst with the sun
The probe launched aboard the Delta IV-Heavy rocket will, over the next seven years, come within 6.16 million kms (3.83 mn miles) of the sun, the closest a spacecraft has ever gotten to the starscience Updated: Aug 12, 2018 20:46 IST
On Sunday afternoon (India time), the U.S. National Aeronautics and Space Administration’s most ambitious mission, the Parker Solar Probe, launched off from Cape Canaveral Air Force Station in Florida for its date with the sun.
The probe launched aboard the Delta IV-Heavy rocket will, over the next seven years, come within 6.16 million kms (3.83 mn miles) of the sun, the closest a spacecraft has ever gotten to the star.
“Parker Solar Probe is a mission of extremes,” Kelly Korreck, an astrophysicist at the Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, said. “It will be the closest human made object to the Sun, going 96% of the distance from the Earth to the Sun. Parker will also be hot - parts of the spacecraft will reach around 3000 degrees Fahrenheit (1649 degrees Celsius)!”
It will also be the fastest human made object traveling at 430,000 miles (6,92,000 kms) per hour, according to Korreck, who is part of the mission. At that speed, you can fly from Delhi to Mumbai in about 6 seconds.
The mission, over five decades in the making, will last 6 years and 11 months, and in this time, the Parker probe will orbit the sun 24 times. With each orbit, it will be propelled closer and closer to the sun, ultimately circling the star at at a distance that is less than 10 radii of the sun.
Here, it will cross paths with Venus, and be flying within the orbit of Mercury, seven times closer to the sun than any other probe.
This means the probe will be in the sun’s atmosphere, a place where conditions can get pretty hot and harsh. However, a 4.5 inch carbon composite shield will face the sun, keeping the instruments cool at around 30 degrees C.
One of the reasons that scientists are sending the probe is to study the Sun’s atmosphere and the weird property it exhibits of being hotter than the surface of the sun itself. It is a puzzle since the further one moves from the source of heat, the temperatures should fall.
The other great mystery is the behaviour of ‘solar wind,’ a stream of charged particles emitted by the sun to release energy. A key question that the probe seeks to answer is how solar wind is accelerated, and for the first time it will be able to look for answers at the very place where this wind originates.
The name ‘solar wind’ was given by Eugene Parker, a professor emeritus of Astronomy and Astrophysics at the University of Chicago, after whom the probe is named. This is the first time NASA has named a mission after a living individual. Parker also described the problem of the heating of the corona, or the sun’s atmosphere.
“We need more understanding to predict these flares and coronal mass ejections as they produce space weather which could affect our technology-based society by damaging satellites and power grids,” Korreck said, adding that “We also get the beautiful northern and southern lights because of these effects.”
The launch of the Parker probe marks the launch of a hectic era in solar physics. The European Space Agency (ESA) is set to launch its own Solar Orbiter early next year.
“We are very excited about the Parker probe, the data from the mission will be public and we will be working with the data,” Dipankar Banerjee, an astrophysicist at the Indian Institute of Astrophysics, Bangalore, said. The first batch of data from the probe is expected to come in December, according to NASA.
India’s own sun mission, Aditya L1 is in its initial stages, according to an Indian Space Research Organisation spokesperson. It is scheduled for launch in 2020. “All the configurations are already over, we are now in the process of assembling the engineering model prototype and then the testing stage will begin,” Banerjee, who is part of the Aditya L1 mission, said.
The Aditya L1 satellite craft will not be getting close and personal with the sun but it will be inhabiting a halo orbit called the L1 point - where a satellite can get unobstructed views of the sun. “The coronagraph on Aditya will attempt to mimic the total solar eclipse that perfectly blocks the solar disk,” Banerjee said. This will enable the craft to collect data about the corona, which is usually not visible because of the bright light of the sun’s disk.
Data from all these missions is expected to shed light on the sun’s fiery character.
First Published: Aug 12, 2018 20:45 IST