WEBVTT FILE

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Well it may not feel like it this week in parts of the country, but today marks

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the first day of Spring. This is the spring equinox and here to tell us

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what a equinox is and else we can expect this year is Dr. Alex Young

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at NASA Goddard Space Flight Center. (Dr. Young) Thanks for having me.

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(reporter) So start by telling us what is exactly is an equinox?

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(Dr. Young) Well the Earth orbits the Sun spinning at a tilt and so sometimes

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twice a year that tilt is actually like this. Meaning that the north

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and south hemispheres get equal illumination from the

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sun. So that's the Spring and Fall equinox's.

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So today in the Northern Hemisphere we are experiencing

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the Spring equinox or the beginning of astronomical spring.

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(reporter) Now there is another exciting event happening this year

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a total solar eclipse. When is this happening and what can we expect?

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(Dr. Young) Well on August 21st the entire Northern American continent

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will get to experience a solar eclipse, where the moon

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moves in front of the Sun, casting a shadow down on the Earth, and those

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in special area called the path of totality about

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70 miles wide. From Oregon down to South Carolina

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will experience the total solar eclipse. Where the disc of the Sun is

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blocked out completely by the moon, allowing us to see it's very

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dim faint outer atmosphere, called the corona, something we

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normally can't see invisible light on the ground, we can only see that

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from space. But a total solar eclipse is special opportunity for us.

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(reporter) Now NASA will be doing some pretty cool science during the eclipse

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Talk about how NASA is using the eclipse to study

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the Sun and Earth. (Dr. Young) Well we're excited to study

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the corona, and that's what we can see during a total solar eclipse

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So it's an opportunity from the ground to it in incredible detail, to

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test out instruments that we would normally fly at some point in space.

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and test them on the ground. We can also experience the effects of

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the change in temperature and light, as that shadow passes across the Earth.

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Which has an impact on our atmosphere as well as the plants and animals around

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We are looking at this corona from a distance, but in

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2018 we are going to send a spacecraft "solar probe plus"

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to fly through that part of the atmosphere that part we're seeing

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during the eclipse, and for the first time actually touch a star.

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(reporter) Talk about how eclipses help us find

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planets orbiting other stars? (Dr. Young) Well the eclipse is a special kind of

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event that is called a transit, where a moon or a planet

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moves in front of a star. When we look at distant stars

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we can see the light dimming from that star and the amount

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of dimming is actually an indicator of how big the object moving

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in front of it is. This is how we find exo-planets in other

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solar systems. So we the TESS spacecraft coming up which is going to give us

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a survey of all these exo-planets, and then allows us

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to eventually use the James Webb Space Telescope to look at the atmospheres

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of these planets to look for signs of life

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in the rest of the Universe.

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(reporter) Very exciting. Where can we learn more, especially about the up coming eclipse?

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(Dr. Young) Well if you go to eclipse2017.nasa.gov

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you can find out the eclipse, you can get lots of imagery and videos, activities

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as well as finding out about safety, how to view it in person

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and how to view it on line.

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(reporter) Great thanks so much. (Dr. Young) Thank you.