Dark matter is thought to make up 26% of the total energy density of the Universe.
Experimental limits and theoretical arguments favour the idea that Dark Matter particles weigh 50-1000 times as much as a proton
If you could make something out of dark matter it would fall straight through the Earth
Billions of dark matter particles may pass through your body every second but only about 35 collide with a nucleus in your body each year.
The amount of Dark Matter going through the Earth must be highest in June and lowest in December because the Earth moves through the Galaxy (and its dark matter cloud) 30% faster in June.
The most sensitive directional dark matter detector in the world, DRIFT-II [link to relevant object], is at the Boulby Underground Laboratory, 1100m below ground in a working Potash mine in North East England
The James Webb Space Telescope (JWST), the replacement for the Hubble Space Telescope, will launch in 2018 and will look back in time to detect some of the first cases of star formation in the early Universe.
Thinnest layer (12km thick) but makes up 80% of the weight of the atmosphere – it is the densest layer
Most of the weather changes occur in the troposphere – the upper troposphere has ‘jet streams’
At its upper edge there’s a maximum ozone concentration – the ozone layer.
Clouds in the stratosphere are rare – the air is dry. High-speed aircraft often fly in the lower stratosphere because of the lack of clouds and storms and because air resistance is so low.
Coldest layer at about -90oC – the formation zone for ice clouds that are visible during sunset.
Usually meteors falling towards the Earth are burned up in the mesosphere – when the meteor hits the atmosphere, the air in front of it compresses very quickly. When a gas is compressed, its temperature rises. This causes the meteor to heat up so much that it glows and is eventually completely burned up. Re-entry temperatures can reach 1650oC.
High concentration of electrically charged particles – produced by UV radiation, X-rays and cosmic rays.
Auroras occur in the ionosphere.
Cosmic rays and high energy particles from space are trapped in the magnetosphere by magnetic forces from the Earth’s magnetism.
The whole magnetosphere is an elongated teardrop shape, going far into space in the direction away from the Sun.
1st weather satellite,TIROS-1, was launched on 1st April 1960 from Cape Canaveral, Florida. It was 42” in diameter, 19” high and weighs 270lb and functioned for just 78 days, wasn’t always pointing at the Earth and could only operate in daylight but managed to send back thousands of pictures of cloud patterns forming and moving across the face of the planet.
Chilbolton Observatory's suite of lidar instruments has been used to detect and track clouds of volcanic ash in the atmosphere