NASA's Newest Spacecraft Will Fly Through the Sun's Scorching Hot Atmosphere (theverge.com)

In T-minus three days, NASA will launch a car-sized spacecraft to investigate our Sun's scorching hot atmosphere. "The vehicle is the Parker Solar Probe, and it's set to launch at 3:33AM ET on Saturday, August 11th, from Cape Canaveral, Florida. "It'll be riding on a Delta IV Heavy rocket made by the United Launch Alliance, which will send the probe zooming toward the inner Solar System," reports The Verge. "Just six weeks after launch, Parker will do a flyby of Venus to alter its route slightly, and then six weeks later, the vehicle will be in the corona. Over the course of seven years, Parker will do 24 orbits around the star, as well as six more Venus flybys so that it can get even closer to the Sun's surface over time." From the report: NASA has long wanted to send a vehicle to the Sun's atmosphere, but such a mission has been considered impossible until the last few decades. This region of space, known as the corona, is filled with tiny, energetic particles that can reach above 3 million degrees Fahrenheit. Any vehicle that ventures near this region must have sophisticated protection to keep from melting. But thanks to advancements in carbon manufacturing and other key areas of engineering, NASA has been able to create a vehicle with a state-of-the-art heat shield and other crucial cooling systems. The result: the spacecraft will stay at room temperature in some of the hottest places in the Solar System.

The Sun's corona is actually 300 times hotter than the surface of the Sun, and no one understands why. The region gets so hot that chunks of the corona actually accelerate and break away from the immense pull of the Sun at supersonic speeds. These so-called solar winds shoot highly energized particles out in all directions, which then slam into surrounding planets. Parker is tasked with investigating the mechanics of the breakaway effect and why the atmosphere is so much hotter than its source.

Comments

Is That Fast?

[mentil]

chunks of the corona actually accelerate and break away from the immense pull of the Sun at supersonic speeds.

What's the speed of sound at the surface of the Sun, compared to sea level on Earth?

Re:Is That Fast?

[Bengie]

Very low then. Sun's surface is 100,000 less dense than Earths atmosphere at sea level.

Re:Delta IV

[oneiros27]

Because it's been planned for YEARS.

You don't build a satellite, then get the lowest bidder. You have to figure out where you want the spacecraft, then which launch vehicles are powerful enough to get something around the weight you estimate into the proper place. Then you have all of the fiddly bits to make sure it's small enough and light enough so you can still reach the right orbit.

(disclaimer: I used to work for the Solar Data Analysis Center)

STEREO's launch was almost delayed (even further than it already was because of the strike + spy satellites cutting in line) because they had to swap to a heavier battery for the self destruct of the second stage ... JPL managed to find an alternate orbit that they could achieve with the extra weight that would still let the mission have a chance at accomplishing its goals.

Re:What i want to know

[Anonymous Coward]

Because heat and tempereature are two different things. I bet the corona is an extremly thin gas. Meaning that even though it is crazy hot, there is very little energy in it per volume. Temperature is the average speed (i.e energy) of molecules in a substance. While heat is the total energy. So even though the corona is a few million degrees celcius, a cubic meter of it might contain way less heat (energy) than one cubic meter of pleasantly body warm pool water.

To keep cool you need to move heat from one place and dump it somewhere else.

Re:What i want to know

[jellomizer]

1. Size: This is a car sized device. the electronics they need to keep cool is probably a small box.
2. Lifespan: Your AC probably works well for a couple of years then become unreliable. There is no chance of us trying to get this device back. The system will work for a while and will die.
3. Environment: Water, Dirt, Dust, Bugs, Hair. will get into your AC system and muck it up. vs operating in a vacuum.
4. Cost: If you want you 12x12x8 foot room to have reliable AC you probably will need to spend millions of dollars in latest material tech to retrofit it. Or just pay a fraction of that total cost, with getting your AC Fixed every few years. I am not sure why you think a satellite cooling system is cheap?

Compared to most things standard Air Conditioning is Simple, Reliable and Cheap.
You can build one yourself with an icebox, a small pump, some metal piping (copper is probably easiest) and a room fan. You can probably fix your yourself with some quick searching. However it is probably cheaper and easier just to replace a home unit. Or replace a part.

 

Re:Room Temperature?

[Nidi62]

If we have the technology to keep part of it at room temperature, then we should have sent actual astronauts instead.

And I am sure you are the first to volunteer to shoot around the sun at 450,000 mph for 7 years in a craft that will most likely be sent spiraling into the Sun once the mission is complete. Oh, yeah, and because the heat shield is only on one side of the craft, any error in attitude means the craft melts and you die a horribly painful but probably pretty quick death.