On Wednesday, November 6th, 2024, the Parker

Solar probe passed within 376 kilometers of the surface of Venus.

The purpose of this close flyby was to accomplish a gravity-assist maneuver where the probe stole some of Venus's momentum for itself so that it could change its orbit and bring itself even closer to the sun.

The probe has already made several close passes of the sun, but the next will be its closest, reaching just a touch above 6 million

kilometers from the solar surface. That's less than nine times the radius of the sun. At the

moment of closest approach, the Parker Solar Probe will be traveling at nearly 700,000 kilometers per hour, making it the fastest

object ever designed by human hands. To give you a sense of just how fast that is, the Parker

Solar Probe gives us the rare opportunity to switch units. We actually can reasonably express its speed as a fraction of the speed of light.

At its maximum speed, 700,000 kilometers per hour, that is .06% C.

We never get to do stuff that lets us say things like that.

That's amazing.

And the mission of the Parker Solar Probe is to

investigate the mysteries of the sun's corona, which is its outer atmosphere. Specifically for

decades, we've known that the visible surface of the sun called the photosphere has a temperature

of around a few thousand Kelvin, give or take. It's hot. But the corona itself, the outer atmosphere, has a temperature of around a few thousand Kelvin, give or take, it's hot. But the corona itself,

the outer atmosphere has a temperature in the millions of Kelvin, which is super hot. And it's like

switching on a light bulb and the bulb itself is warm to the touch, but the air around it is a

thousand times hotter.

What gives?

Well, what gives?

I'm going to tell you right away that the answer is magnetic fields.

Now, if you've listened to this show for any length of time, you know that magnetic fields

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