[00:00.10]From VOA Learning English,
[00:02.16]this is the Education Report.
[00:05.34]Students at Saint Louis University
[00:07.58]are launching weather balloons
[00:09.52]into the sky above St. Louis, Missouri.
[00:12.91]The United States space agency NASA
[00:16.14]is paying for this activity.
[00:18.48]It's a part of a study to improve
[00:20.92]our understanding of air pollution and climate.
[00:24.80][VOICE]
[00:47.05]A group of students surround a laptop computer
[00:52.67]and a radio receiver outside the Saint Louis Science Center.
[00:57.85]They're getting ready to take part
[01:00.14]in a NASA project to measure ozone.
[01:03.42]The students hear the sound of information.
[01:07.06]Inside container made of Styrofoam material
[01:10.89]are small instruments, they measure direction,
[01:14.48]temperature, humidity, air pressure and ozone.
[01:19.86]The students tested all the instruments.
[01:22.89]When they are certain everything is operating correctly,
[01:26.58]they attach the container to a weather ballon.
[01:30.06]The ballon will carry it into the atmosphere
[01:33.59]three times higher than jets airplane.
[01:36.69]But first, the students need to fill the ballon
[01:40.37]with helium gas, so it can rise.
[01:43.51]They need a lot of helium.
[01:46.83]Fully blown up,
[01:48.41]the ballon will be 2 to 3 meters in diameter.
[01:52.84]A voice announces the launch time.
[01:55.73]"This is Gary Morris with the Saint Louis University
[01:58.61]weather balloon launch team at the St. Louis planetarium.
[02:01.50]We're five minutes from a weather balloon launch."
[02:03.49]Gary Morris is a professor at Valparaiso University in Indiana.
[02:09.32]He is the lead trainer for the nationwide study.
[02:13.16]The professor says NASA wants more information on ozone
[02:18.29]because * affects our atmosphere ― both good and bad.
[02:23.08]High up in what is called the stratosphere,
[02:26.47]the ozone layer keeps harmful ultraviolet radiation
[02:30.80]from reaching the earth.
[02:32.35]But near the ground, emissions from cars and petrochemical plants
[02:37.78]form ozone pollution and smog,
[02:40.82]the unhealthy air condition that affects breathing.
[02:44.50]Jack Fishman leds the ozone study at Saint Louis University.
[02:50.18]He says new requirements that decrease pollution
[02:53.91]have lowered ozone levels in American cities,
[02:57.80]but he notes that pollution in remote areas continues to increase.
[03:03.17]He blames industrial activity in eastern Asia for that pollution.
[03:08.75]Mr Fishman says polluted air is being blown across
[03:12.94]the Pacific by currents in the upper atmosphere.
[03:17.08]He says ozone pollution has slown
[03:20.12]the growth of farm crops and forests.
[03:23.42]And now, at the Saint Louis Science Center,
[03:27.30]is time for the balloon launch.
[03:29.24]OK, comes a voice, ready...
[03:31.78]"Five, four, three, two, one, lift-off! Alright!"
[03:41.29][VOICE]
[03:50.05]And that's the VOA Education Report.
[03:54.39]I'm Jerilyn Watson.