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(THEME) VOICE ONE: This is Steve Ember. VOICE TWO: And this is Faith Lapidus with the VOA Special English program EXPLORATIONS. You are listening to our program today on a radio. Almost no communication would exist in the world without the electromag
2018年VOA慢速英语(九)月
Earth Station - The term used to describe the combination of antenna, low-noise amplifier (LNA), down-converter, and receiver electronics that are used to receive a signal transmitted by a satellite.
电信英语
Scientists have solved the mystery behind the brilliant northern and southern light show known as Aurora Borealis. The phenomenon is caused by electromagnetic energy from the sun, which experts say also wreaks havoc on ground-based power grids and s
VOA标准英语2008年（七月）
The solar system is a hostile place. Earth is under attack from deadly cosmic radiation. Life here is only possible, because it's protected by the magnetosphere, an invisible force field that cocoons the planet. But new evidence reveals that this vit
自然百科2011年
On a previous Moment of Science we discussed one of the problems with turning yourself invisible. Sure, it sounds like fun. But a little physics showed us that the invisible man couldn't see anything either, because in order to see, light has to inte
英语时差8，16
Do you remember who won the world series in nineteen sixty- eight, but forget where you left your keys? Are you great at remembering all the details of a story, but lousy when it comes to remembering peoples names? What our brains choose to remember,
英语时差8，16