NASA发射一颗新型太阳观测卫星

-I’m Chris Kaufman and I’ here with Justin Kasper, who works at Smithsonian, he’s an astrophysicist at the Smithsonian. And he's won a project that’s gonna launch a probe at the sun, specifically the Solar Wind Electrons Alphas and Protons investigation, SWEAP

-That’s right

-Investigation, is that right?

-Right.

-Ok, let’s start with why.

-There’re two overline reasons why we wanna send a probe into the sun’s atmosphere. The first is we don’t understand why the sun’s atmosphere, which we call the corona is heated to such high temperature, so if you look at the sun right now, it glows a kind of blindingly yellow color, and it’s yellow because it’s had the temperature of around 6,000 degrees. About 100 years ago, people realized that above the surface of the sun, the temperature actually rises by that factor of 1,000, so the sun’s 6000-degree-surface is surrounded by an atmosphere that’s had a temperature of 1 to 10 million degrees, and that’s just basic physics we wanna be able to understand. What on earth is going on at the surface of the sun that gives an atmosphere that’s had 1 million degrees, you know, that’s just basic physics we wanna be able to understand.

-Ok, let’s come back to why then again, because you give a very good cogent scientific answer as to why, but I’m curious as to the practical applications of why. What are we gonna learn that might help us in the future and how are we gonna use that information?

-Well, I mean, what I love about solar probe is there’s basic physics we’re going after, but at the same time, we’re going after some really important practical knowledge that can help society. So if I could go back about 150 years, there was a huge solar flare in 1859, it caused all sorts of wild effects at earth, compasses started wiggling around, the aurora borealis was seen all the way down in Hawaii and Bahamas, and sparks started to fly from telegraph lines, in fact, the entire worldwide telegraph system, which we can think of as the internet of the Victorian age, shut down and wouldn’t operate for about 3 days, just from all this electrical activities caused by the sun, I mean, we don't have telegraph lines, but we have power lines
crisscrossing all over the country,

-satellite

-Satellites, we love our GPS, we love our satellite phones and our satellite radio, so we’re really dependent on this technology that depends on electricity, and the Natural Academy of Sciences found that if we didn’t have enough advance warning the power system is down, you might do up to 2.5 trillion dollars’ worth of damage to the US just with that one event, and you could be looking at a total loss of electrical power on the eastern seaboard for instance, for up to a year.

-Let’s talk about the probe itself, first of all, does this have some kind of name?

-Solar probe plus we call it.

-Solar probe plus. ok now, solar probe plus. what’s it made of, I mean, we thought that  most physical materials on earth might melt.

-Absolutely, absolutely,

-So what’s it made of and how did you put up something together that might be able to survives this?

-So a lot of people have worked a very long time on coming up with the design for the space craft. And our closest approach which will be about 8.5 solar radii above the surface, so just a few percent of the distance from the sun towards the earth, and incredibly close. So any surface that’s exposed to the sun might get up to 1300, 1400 degrees Celsius, so almost anything, you know, you can’t use steel, you can’t use aluminum, you can’t use your standard building materials, so the entire front of the space craft is made of this incredible new material called carbon foam. It’s this really low density material, it’s a better insulator than almost anything on the planet.

-So we start out, you launch in 2018, that’s the plan, how long, it’s 5 years, I believe, right? A 5 year program, how much is this costing?

-Ok, so the, what we call the life cycle cost of the entire mission is approximately 1.3 billion dollars, and that’s spread out from when the project began in early prototyping several years ago, out through when we kind of close out, publish the last data and then lock things up out in 2026. There’re 31 institutions that are involved. So you’re talking about hundreds of scientists, students and engineers around the country that each played a role in the project.

-Just one quick final question, what happens to the probe, does it come back, does it go into the sun in the end, does it blaze of glory, you know, it’s gonna be some great scene that we wanna capture from earth, and see what happens to it.

-That’s a great question, everyone wants to know that, absolutely, now if nothing else goes wrong, one day we’ll use up our fuel, and the space craft will flip around and at that point, within seconds, it’ll burn up,

-Well, let’s hope that you get everything you need out of it, Justin Kasper, best of luck and we’ll look forward to seeing what comes from the sun.

-Thank you, great. I’ll let you know.