Unprecedented Solar Proximity


By Girish Linganna

On December 24, 2024, NASA’s Parker Solar Probe is set for a historic journey, edging closer to the Sun than any other man-made object before. Achieving record-breaking speeds of 195 km/s (435,000 mph), it will be the fastest artificial object in history. The probe aims to approach the Sun at a distance of just 6.1 million km (about 3.8 million miles), a feat unparalleled in human engineering. Dr. Nour Raouafi, who leads the project, told BBC that this mission is akin to virtually touching a star, highlighting its extraordinary significance.

No man-made object has ever traveled as fast or come as near to the Sun as this – it will be just 6.1 million km or 3.8 million miles away from the Sun’s surface.

Dr. Nour Raouafi, the scientist working on the Parker project, said it’s almost like we’re landing on a star. He also mentioned to BBC , that this is a huge milestone for everyone. It’s as significant as the Moon landing in 1969, according to the scientist from Johns Hopkins University Applied Physics Laboratory.

The Parker Solar Probe, launched by the US space agency in 2018, is on a bold mission. It aims to approach the Sun closely and repeatedly. By late 2024, it’s expected to get within just 4% of the distance between the Sun and the Earth, which is about 149 million kilometres or (14.9 crore kms ) 93 million miles. Distance between Earth and Sun is approximately 150 million Kms (15 Crore Kms )

Parker, a space probe, faces a big challenge. When it’s closest to the sun, the front of the spacecraft will likely heat up to 1,400 degrees Celsius. Its plan is to quickly move in and out, using instruments protected by a heavy heat shield to study the sun’s surroundings. Scientists are hoping this will lead to important discoveries, especially about the corona, which is the outer layer of the sun’s atmosphere.

The sun has a strange heating pattern. Its surface, the Photosphere, is about 6,000 degrees Celsius, but its outer layer, the corona, can get over a million degrees. Normally, you’d expect it to get cooler the further you are from the sun’s center. Also, in the corona, particles like electrons and protons suddenly speed up a lot, creating a very fast wind that moves at about 400 kilometres per second, which is really fast.

Scientists still don’t fully understand these phenomena, but it’s crucial for making better predictions about the sun’s actions and “space weather.” This weather involves strong releases of particles and magnetic fields from the sun that can interfere with communication on Earth and even cause power failures. This kind of solar activity also creates radiation that is harmful to astronauts. This is particularly important to consider as we’re planning to send astronauts back to the Moon and set up a permanent station there, as Dr. Raouafi pointed out.

Parker recently made a close pass by the Sun on 29th Dec 2023 and has three more such passes scheduled for this 2024. After these, it will use Venus’ gravity on November 6 to change its path for a significant event on December 24.

Dr. Nicky Fox, who now leads NASA’s science division and was previously the main scientist on the Parker mission, discussed the upcoming December 24 flyby. She highlighted that the probe would spend a longer time in the sun’s corona than in any previous mission.

Speaking to BBC News, she mentioned that they’re not sure what they’ll discover, but they will be looking for waves in the solar wind that might explain the heating. Dr. Fox expects to detect various types of waves, which could help understand different theories that scientists have debated for a long time.

2024 will be the most important year for Parker’s mission. After December 2024, it won’t be able to get any closer to the Sun because its path won’t pass by Venus anymore, which helps to adjust its route for a closer approach. Also, getting closer to the Sun could mean less protection from its large shield, making the back of the spacecraft too hot to handle.

To clarify, December 2024 marks a crucial moment for the Parker mission as it will be at its nearest safe distance to the Sun. This close approach in December is due to well-planned movements and the path the spacecraft follows. After December, Parker will no longer be able to use Venus to change its path for a closer approach. Therefore, this month signifies the closest point Parker can safely get to the Sun without its shield being overwhelmed by the Sun’s intense heat. (IPA)