Parker Solar Probe to contact the sun


On 12 August 2018, NASA launched a spacecraft called the Parker Solar Probe1,2—the first ever mission intended to fly directly into the sun’s atmosphere, called the corona, which is normally visible from Earth only during total solar eclipses.

The purpose

NASA artist’s concept of the Parker Solar Probe approaching the sun. Notice the solar panels (shown in the fly-by-Venus image) are now folded back into the shelter of the heat shield.
Credit: NASA/JHUAPL/Gribben

The primary science goals of the project are to determine why the corona is several million degrees hotter than the surface of the sun (which is called the photosphere because it emits light), and why it produces the solar wind (a stream of plasma that travels outward from the sun through the solar system), solar flares, and coronal mass ejections.

The probe will carry four instrument suites designed to image the solar wind, and to study magnetic fields, plasma, and energetic particles. Practically it is hoped that this will improve how to predict dangerous solar storms that can affect power networks and communications on earth, as well as impact satellites and astronauts in space.

Protection from the sun

NASA artist’s impression of the Parker Solar Probe flying past Venus. The front-mounted heat shield will protect the instruments when the craft approaches the sun. Notice the two extended solar panels that provide power for the craft in orbit.
Credit: NASA

To protect the Parker probe’s instruments from the sun’s radiation,3 the spacecraft, which is about the size of a small car, has been fitted with an 8-ft-diameter (~2.5 m) hexagonal heat shield designed to protect everything within its umbra, i.e., the shadow it will cast on the spacecraft. It has been designed to keep the spacecraft’s payload at 30º C (85º F), while the shield reaches 1,370º C (2,500º F).

NASA advises that the heat shield consists of a layer of lightweight 4.5-inch-thick (~11.5 cm) carbon foam sandwiched between two panels of another carbon-composite material, mounted on the sun-facing side of the spacecraft. Also, the sun-facing side of the heat shield has a specially formulated white ceramic paint coating to reflect as much of the sun’s energy away from the spacecraft as possible. The coating contains bright white aluminium oxide. To prevent this reacting with the carbon of the heat shield and turning grey, the coating is separated from the heat shield by a layer of tungsten thinner than a strand of hair.

The shield has to face the sun at all times, so Parker has a sophisticated control system that is fully autonomous. This is because a radio signal from the craft near the sun would take about eight minutes to reach Earth, and a reply would take another eight minutes. A suite of sensors will tell the spacecraft if it is tilting too much and if so will immediately make adjustments to its orientation.


The Parker Solar Probe will orbit the sun 24 times, seven of which will involve flybys of Venus, to gradually shrink its orbit around the sun.

Having taken off from Florida on 12 August, the Parker Solar Probe will fly by Venus on 2 October, and then reach the sun for the first time on 5 November. It will now be in a Venus–sun elliptical orbit, which it will fly some 24 times, using gravity from flybys of Venus on seven of these orbits to remove the inherited Earth’s angular momentum from its orbit. This will reduce the orbital speed at aphelion (the point furthest from the sun, in this case Venus).

The reduction required is too much for just one flyby—seven are required as the orbit gradually shrinks and brings the spacecraft closer and closer to the sun. So these flybys of Venus are for the purpose of decreasing the spacecraft’s velocity, not for increasing it, and the Venus–sun orbital periods will decrease from 150 days for the first flyby to 88 days for the seventh.

The sun’s apparent size as the Parker Solar Probe will see it compared to how we see it from Earth.
Credit: Wikimedia Commons

On its first orbit, Parker will be about 24 million km (15 million miles) from the sun at its first perihelion (the point nearest to the sun).4 On its final orbits in 2024, at perihelion it will be about 6.1 million km (3.8 million miles) from the sun’s surface. This will be seven times closer than any previous spacecraft has achieved. NASA predicts the probe will fly at speeds of up to 700,000 km/h or 200 km/sec (430,000 mph or 120 miles/sec) at perihelion.5

Real science vs historical speculation

All of this is a great example of ‘real’ science—operational science, trying to find out more and more about the makeup and operation of the universe we live in. This is far removed from speculations about how it all is supposed to have arisen.

Operational science (sometimes also called experimental science) is firmly based on the confidence and knowledge (faith) that the universe operates in a way described by unchanging physical laws. These laws permit NASA’s scientists and engineers to power, guide and control its solar probe in the ways described here, totally confident in the results of their calculations.

It is instructive and fascinating to realize that the discovery and elucidation of these laws is now widely acknowledged (even if grudgingly by some) to have been a natural outgrowth of a biblical world view (elegantly explained in The biblical roots of modern science).

It is no coincidence that the ‘giants’ of science’s birth (Newton, Faraday, Maxwell (Einstein’s heroes), Kepler, etc.) all shared that perspective. Without it, modern science would not have been born. If there is no unchanging, non-capricious Creator/Lawgiver, why should there be laws capable of being discovered anyhow? Why not just general vague approximations?

Why can we absolutely trust that the laws will always hold with total, unwavering precision? Or that they will be the same in the solar neighbourhood as here on Earth? Today’s mostly unbelieving scientists have learned from generations of experience that this faith is always justified; but having largely rejected the God of the Bible, they have no actual basis for it outside of that it always seems to be that way. Indeed, they can’t prove this by any scientific experiment, because the experiment would always need to assume the very constancy of laws it’s trying to prove. Not so for science’s founders, who unquestioningly accepted the history in the Bible that the entire universe was created by the one Creator God, Jesus Christ, who is “the same yesterday, today and forever” (Hebrews 13:8).

Parker probe excitement

Scientific enterprises like the Parker Solar Probe are indeed exciting, and we are bound to learn more about our world from it. And as often happens, there may be various commercial spinoffs that benefit mankind in unanticipated ways. This would further fulfil mankind’s ‘dominion mandate’ of Genesis 1:26, given before the Fall and not withdrawn after it.

It’s also a great time for families to share about how this sort of science differs from evolutionary/big bang speculation about unobserved past events, and to reflect on the lawful world God made. Families that use quality creation materials can raise the next generation of believers to understand that loving science does not mean swallowing the evolutionary stories. Christian parents who do this can encourage their offspring to get into careers in science, confident in the knowledge that God’s world will always confirm and conform to God’s Word.

Published: 14 August 2018

References and notes

  1. Originally named Solar Probe (before 2002) and then Solar Probe Plus ( 2011–17), but renamed Parker Solar Probe (May 2017) in honour of University of Chicago scientist Eugene Parker (b. 1927), who, in the mid-1950s, developed the theory of the supersonic solar wind and predicted the Parker spiral shape of the solar magnetic field in the outer solar system. Return to text.
  2. The spacecraft was launched on a United Launch Alliance Delta IV Heavy Rocket from Space Launch Complex 27 at Cape Canaveral Air Force Station in Florida. The largest of the Delta 4 family, the Heavy version features three Common Booster Cores mounted together to form a triple-body rocket. Return to text.
  3. The incident solar radiation near the sun will be approximately 520 times the intensity at Earth orbit. Return to text.
  4. This is about half the perihelion of Mercury. Return to text.
  5. Like every object in orbit, the spacecraft will accelerate as it approaches perihelion, and then slow down until it reaches aphelion. This is described by Kepler’s Second Law, and explained by Newton’s laws of motion and gravity. Return to text.