This Column published 2-part article titled “Solar System: NASA Solar Mission” on 17th and 24th August 2018. In the article, concerted efforts to “touch” the Sun by National Aeronautics and Space Administration (NASA) were presented. NASA is an American famous agency with clear mandate on space exploration as stated in her vision “We reach for new heights and reveal the unknown for the benefit of humankind”. This vision of space exploration is diligently being pursued with billion of US Dollars on annual basis on. The level of investment by American taxpayers to make NASA achieve her lofty goal is enormous, gargantuan and shows the seriousness of USA in space technologies. The worthiness of the spacecraft was estimated to cost a princely amount of 1.5 billion US Dollars. Thus, there was a high level of human enthusiasms, support for NASA by the American citizenry and scientists worldwide when a spacecraft was launched to “touch the sun” and break the inscrutable and mysteries surrounding this giant star called “Sun”.
As stated in my earlier article, the spacecraft called “Parker Probe”, launched on 12th August 2018 was a collective product of six decades of scientific research work and brainstorming in series of meetings, conferences, symposiums and similar forums. As the brainstorming was going on, construction of the spacecraft commenced, lasting for several years which resulted in the successful development of Parker Solar Probe, the spacecraft that is currently on its mission of flying much closer to the sun than any of the previous missions ever done in the history of space exploration. Parker was named after astrophysicist Eugene Parker, the S. Chandrasekhar Distinguished Service Professor Emeritus in the Department of Astronomy and Astrophysics at the University of Chicago, who discovered the phenomenon now known as solar wind. Parker Probe mission is not the first attempt to reach out to the sun, before it, there was Genesis mission. That mission was the first spacecraft to capture a sample of the solar wind, or the constant stream of particles that emanate from the sun. The Genesis performed an amazing three-year sampling round at a gravitationally stable area in space known as “Lagrange 1” before returning to the Earth. Unfortunately, the spacecraft made a hard landing after its parachute failed, according to NASA, but some of the sample did survive. Genesis mission was between the year 2001 and 2004. From that mission, scientists discovered evidence that our planet, Earth, was possibly formed from different solar nebula materials than those that created the sun.
Parker Probe mission was launched to make 24 orbits of the sun before swooping into the outermost part of the solar atmosphere, known as the corona, to study the sun up close and personal. A jacket of gases called an atmosphere surrounds the Sun. The corona is the outermost part of the Sun’s atmosphere. There is a great mystery beyond human comprehension about the corona. Although, the corona is far away (millions of kilometers) from sun but it is much hotter than the surface of the Sun. The surface of the Sun is about 10,000 degrees Fahrenheit, but the corona can be as much as a hundred times hotter — with temperatures of about a million degrees. It is the most mysterious thing; it’s like getting hotter as you walk away from a blaze. Parker Probe is expected to bring information that could assist to resolve this mystery.
This week of December 16th 2018, Parker Probe spent 19 weeks of its 6-year mission to make the 24 orbits round the Sun. How successful has the mission been? So far, the mission has been so good. Six weeks ago, precisely on November 16th, the mission control unit of Johns Hopkins Applied Physics Laboratory received feedback from the Parker Probe that all systems were operating well and as expected. The feedback indicated that sun, the centerpiece of solar system and the most important source of energy for life on Earth, has received a man – made visitor. This milestone was achieved on October 29th when NASA’s Parker Solar Probe became the closest man-made object to the sun at 6.128 million kilometers away. This momentous landmark outperformed the previous achievement recorded for the German-US Helios 2 satellite that was at 42.48 million kilometers away from the sun. In the next five years, the Parker Probe will orbit closer to the sun with the closest approach in the year, 2024. The report also indicated that in some days November 2018, the probe completed its first solar encounter phase through the sun’s outer atmosphere, the corona. An online paper “Mother Nature Network” quoted one of the NASA scientist saying “Parker Solar Probe is providing us with the measurements essential for understanding solar phenomena that have been puzzling us for decades,” said Nour Raouafi, Parker Solar Probe project scientist at the Johns Hopkins University Applied Physics Lab. “To close the link, local sampling of the solar corona and the young solar wind is needed and Parker Solar Probe is doing just that.” The statement added that “Placed in orbit within 6.4 million kilometers of the sun’s surface, and facing heat and radiation unlike any spacecraft in history, the spacecraft will explore the sun’s outer atmosphere and make critical observations that will answer decades-old questions about the physics of how stars work. The resulting data will improve forecasts of major space weather events that could impact life on Earth, as well as satellites and astronauts in space.”
To avoid melting Parker, just like the idiom “Don’t fly too close to the sun”, which originated from Greek legend ‘Icarus’, whose wings melted when he flew too close to the sun, Parker Probe was designed to avoid a similar catastrophe of melting when too close to the Sun. To protect its instruments from temperatures approaching 2,600 degrees Fahrenheit (1,426 degrees Celsius), the Parker Solar Probe is shielded with an 8-foot-wide 4.5-inch-thick carbon-composite foam called the ‘Thermal Protection System (TPS)’, TPS weighs only 160 pounds and has an internal structure of 97 percent air. The engineering behind its design is so efficient that those components protected on the shaded side will astoundingly experience nothing more than a room temperature of 21 degree Celsius. NASA installed the shield in June after it was briefly attached late last year just for testing.
Parker Probe was built similar to Cassini spacecraft, which spent twenty years in space with thirteen of such years exploring Saturn. Cassini mission revealed in great detail the true wonders and astounding worlds of Saturn, a giant world ruled by raging storms and delicate harmonies of gravity. Like Cassini that dove toward Saturn, the Parker Probe will experience no fewer than 24 close encounters with the sun using repeated gravity pulls from Venus. Its most precarious dive through the sun’s outer atmosphere, projected to occur in 2024, will have it passing by the sun’s surface at a distance of only 6.08 million kilometers. As a comparison, the closest NASA has ever approached the sun is from a distance of 43.1 million kilometers with the Helios 2 spacecraft in 1976.At that point, the Parker Solar Probe will make history by becoming the fastest man-made object ever with record-breaking speed of 720,000 kilometers per hour.
In the next five years, Parker Probe is likely to bring bundles of information that will make scientists resolve the mysteries of the sun’s corona, the sun’s atmospheric surface seen during the solar eclipse from the earth, which is hundred times hotter than actual body of the sun. A kind of the “the more you move away from the fire, the hotter it comes”. This type of mystery defies the laws of physics known by mankind.
While the World awaits more information as Parker Probe mission continues, for the umpteenth times, it must be noted that cosmos and space were divinely made beyond total human comprehension. Thus, mankind should limit his study of these perfect creatures to only those that can benefit Earth, the only known planet with living things, beyond this, it could be disastrous. May God forbid.
Professor Othman is the Executive Director of National Agricultural Extension and Research Liaison Services (NAERLS), ABU Zaria.