WEBVTT FILE 1 00:00:01.400 --> 00:00:07.070 Let’s say this is the equivalent of the sun’s total energy output. 2 00:00:07.090 --> 00:00:12.230 You can accumulate a hundred dollars a lot of different ways… 3 00:00:12.250 --> 00:00:13.830 But a hundred bucks… 4 00:00:13.850 --> 00:00:17.560 …is a hundred bucks! 5 00:00:15.580 --> 00:00:18.770 If energy from the sun were a hundred dollars, 6 00:00:18.790 --> 00:00:22.530 it would be important to know what kinds of currency was coming in— 7 00:00:22.550 --> 00:00:23.810 big groups of pennies … 8 00:00:23.830 --> 00:00:25.290 …whole dollar bills… 9 00:00:25.310 --> 00:00:27.820 …or combinations. 10 00:00:27.840 --> 00:00:30.580 The total amount of solar energy falling on Earth 11 00:00:30.600 --> 00:00:34.880 generally doesn’t vary more than about 1 dime to \$100 12 00:00:34.900 --> 00:00:39.390 but the kinds of energy from the Sun can fluctuate. 13 00:00:39.410 --> 00:00:42.190 Remember that light we see with our eyes 14 00:00:42.210 --> 00:47:59,890 is actually a combination of many different colors, or wavelengths. 15 00:47:59.910 --> 00:00:49.630 That’s true also for the light we do NOT see. 16 00:00:49.650 --> 00:00:53.290 The composition of that light matters to understanding Earth’s energy budget, 17 00:00:53.310 --> 00:00:59.770 and that’s the reason NASA has a new instrument designed to study this question. 18 00:00:59.790 --> 00:01:00.510 It’s called TSIS— 19 00:01:00.530 --> 00:01:06.820 —the Total and Spectral Solar Irradiance Sensor. 20 00:01:06.840 --> 00:01:08.550 It is important to know that the Sun supplies 21 00:01:08.570 --> 00:01:11.910 virtually all of the energy coming to Earth. 22 00:01:11.930 --> 00:01:15.880 But...inbetween the Earth and the Sun 23 00:01:15.900 --> 00:01:16.320 there is the atmosphere. 24 00:01:16.340 --> 00:01:19.920 In the atmosphere there are clouds, there are aerosols-- 25 00:01:19.940 --> 00:01:24.920 that is particles--there are gasses 26 00:01:24.880 --> 00:01:26.810 that interefere with solar radiation reaching Earth. 27 00:01:26.830 --> 00:01:27.170 So, that's why we need to fly a satellite.... 28 00:01:27.190 --> 00:01:28.510 to be above the atmosphere 29 00:01:28.530 --> 00:01:31.970 Mounted to the International Space Station, 30 00:01:31.990 --> 00:01:35.220 TSIS will collect detailed assessments of solar energy. 31 00:01:35.240 --> 00:01:38.340 Those data will be vital for scientists 32 00:01:38.360 --> 00:01:41.420 to make more accurate forecasts about climate change 33 00:01:41.440 --> 00:01:57.899 and other interactions between our planet and our parent star.