I love eclipses. Solar are the best and most dramatic, but there is still something quite magical about a total lunar eclipse. The Full Moon fades in brightness and eventually turns a deep red colour.
The second total lunar eclipse of 2011 occurs on 11 December. The Moon will enter the Earth’s shadow at 11:45 pm (Australian Eastern Daylight Saving Time) and be fully red at 1:06 am.
More details at: http://en.wikipedia.org/wiki/December_2011_lunar_eclipse
Most of the time the Sun is quiet, shining in space beaming out light and heat. But every eleven years it gets cranky – covered in dark spots and fiery eruptions. This is a time called solar maximum, or solar max for short.
The Sun, like all stars, is a big ball of plasma – mostly hydrogen and helium. Because the Sun is so big – 100 million times bigger than Earth – it has a lot of gravity. The gravity squeezes the plasma so hard that it gives off heat and light. Scientists call this nuclear fusion.
Twenty years ago, the answer this question was ‘only one that we know’. Most astronomers believed that the Sun was no different to most stars in the universe. So if we had a star with planets and moons – a solar system – than why don’t others.
In 1992, the first planet orbiting another star – sometimes called an exoplanet – was detected. Since then, astronomers have used larger telescopes and faster computers to find more than 450 exoplanets orbiting more than 300 stars.
A busy week for me as I had to fill in some blanks in the schedule. One story was on genes relating to menarche (onset of female puberty) and the other was traces of oxygen found on Saturn’s moon Rhea.
Astronomers measure the distance to other galaxies by looking at their colour. The more red a galaxy is, the faster it is moving from us and the further it is away.
Another way to measure distance is to look at the brightness of exploding stars – called supernova. These explosions are brighter the closer they are to us. By measuring the brightness it is possible to know how far away they, and the galaxy they live in, are from us.
Using these techniques astronomers have seen galaxies more than 13 billion light years away.
Space telescopes that measure cosmic background radiation, which are the remains of the Big Bang explosion. It is thought to be the outer edge of our Universe and is 13.7 billion light years away.
