Text on screen: Why does space weather matter to us on Earth?
Well, space weather is this whole field of understanding solar storms – huge eruptions that happen on the sun and travel through the whole solar system and sometimes they impact the Earth.
And these solar storms interact with our electronics, with our technology and in some cases they can create a radiation environment, which is hazardous to space travelers.
So it is critical that we understand them both to make sure we can keep them from impacting our technological society as well as making our astronauts and future travels to Mars safe.
Text on screen: How has STEREO changed our understanding of the sun?
Well, the great thing about STEREO is we now have a new perspective – we can see the sun from the side, we can see the sun from the back for the first time in history.
In the past we only saw things looking straight at the Sun from the Earth and saw them coming directly at us. It’s very difficult to see how fast things are, what their real structure is.
But, then once you move out to the side or even to the back you have additional perspectives, which really show you the structure, the shape, how these things are traveling, how fast they’re traveling and ultimately to better understand them.
So STEREO has given us this unique view, which has allowed us to understand space weather in ways that we never have before.
Text on screen: We're gearing up for the solar event of the century in the US - the August 2017 solar eclipse. How does an eclipse help us understand the sun?
An eclipse, in particular a total eclipse, is a really unique opportunity to see the lower part of the sun’s atmosphere called the corona. And this is something that is very difficult to see unless the sun’s disk is completely blocked out.
This outer part of the sun’s atmosphere is millions of times dimmer than the sun’s disk, so the moon blocking it out allows us to see this and to see it from the ground. And this is important because this is the area where all the action happens.
This is where solar storms originate, where the eruptions come from and this means that during a total solar eclipse we can finally look at all this really amazing structure in ways that we normally couldn’t do.
Text on screen: NASA has an upcoming mission that will for the first time touch the sun. Can you tell us about that?
Well, not too long from now in a couple of years, NASA will be launching a mission called the Solar Probe Plus. And this mission is going to literally travel to the sun. This is the first time mankind has gone to the sun.
And we’re going to fly through the sun’s atmosphere – sort of like flying over the cloud tops – scooping up, looking at what’s happening as well taking samples and measuring the sun’s atmosphere.
So this is going to be happening in the area that we are talking about during a total solar eclipse and an area that STEREO allows us to see, but now we are going to be there. We are not just going to be looking from a distance, but we are going to be there, in person, for the first time in history.
Text on screen: We heard STEREO-B was giving NASA the silent treatment for a while. Can you tell us what happened?
Well all spacecraft have to deal with interference from the sun. The sun is very bright. It puts out light in all different wavelengths – every wavelength you can think of – and so, it often becomes a source of noise for spacecraft.
But generally that noise is only over a very short period of time. Because STEREO has traveled back around behind the sun, when we looked to the spacecraft we have a period of over three months that it was extremely noisy and we were unable to communicate with the spacecraft.
Unfortunately, for STEREO-B, one of the two spacecraft, when we past that period of silence we were not able to regain contact with STEREO-B.
So it hasn’t – we’ve only been able to regain some contact after almost 24 months of silence.
Text on screen: Why are you so excited about STEREO, this anniversary and how NASA studies the sun?
Well, STEREO is really exciting in the first place because it is the first time that we have seen the entire sun, 360 degrees, all at the same time. So that is the first time in history that we as – uh – human beings have been able to see the whole sun at once.
So that in itself is very, very amazing. But also on top of that, STEREO was only really designed to be around for two years and we’ve had it now for ten years.
So, not only is it a scientific marvel in terms of what it has enabled us to understand about space weather and solar storms, but it’s an engineering marvel. It is - was the first time we were launching two spacecraft like that, in that kind of orbit, and it still keeps on ticking after all this time.
So, it’s really an exciting, exciting mission for NASA for science, for technology, engineering. And it is something we hope continues to go on and continues to bring back new and exciting information – uh – over the next few years.
Text on screen: Where can we learn more?
Go to www.nasa.gov/sunearth to find out more about STEREO and all the other solar missions that we have here at NASA.