Jasmine: I'm Jasmine.
Chrissy: And I'm Chrissy.
Jasmine: We're from NIU STEAM and...
Chrissy: This is the Sound of Science on WNIJ.
Chrissy: Well, it's official! Puxatawny Phil didn't see his shadow!And if you listened to The Sound of Science a few weeks ago you know that it most certainly going to be Spring in the next week because he says so. Thank goodness for the groundhog!
Jasmine: Hold on one second! There's a more precise way to describe the seasons and it involves astronomy. The First Day of Spring has to do with Earth's position in Space within its orbit around the Sun.
Chrissy: Let's jog our memories...The Earth takes approximately 365 days to make its way completely around the Sun and the Earth doesn't sit straight up and down on its axis, like a top, but rather tilts at an angle of approximately 23.5 degrees. It's the tilt of the axis which determines what season a particular hemisphere is having. If the hemisphere is tilted towards the Sun, the experience is Summer. If the hemisphere is tilted away from the Sun, the experience is Winter. The tilt of the Earth is also
responsible for the amount of daylight we see on a given day. It all has to do with the angle at which the Sun's rays strike the surface of the Earth.
Jasmine: On March 20th of this year, the First Day of Spring will occur. Otherwise known as the Vernal Equinox, with vernal meaning "pertaining to Spring" and equinox being a combination of Lain words meaning "equal night". Astronomically, the earth will be at the point in its orbit where, for a moment, the Earth's axis is neither tilted away nor towards the Sun, and on the surface it will appear as if the Sun is directly over the Equator. This will allow us to experience approximately the same amount of daylight as we do night. Once the Earth passes this point in its orbit, the effects of the tilt will again be observed as the Northern hemisphere begins a warming trend that leads to summer.
Chrissy: Climate and regional geography will determine when the meteorological effects of Spring are truly felt, but the Vernal Equinox is recognized globally as the official start of Spring.
Jasmine: You have been listening to the Sound of Science on WNIJ, where you learn somethingnew every day.
