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BIG QUESTONS IN ASTRONOMY

THE AGE OF THE UNIVERSE

The age of the expanding universe can be calculated by extrapolating back to the time when the Big Bang must have occurred (about 10,000 million years ago). Old Stars in globular clusters appear to be twice this age.

DARK MATTER

Globular clusters of stars rotate about most galaxies (just like Planets rotate about the Sun). The mass of the galaxy needed to keep them in orbit is much greater than the known mass of the galaxy. In fact, only a few % of the necessary mass can be seen; the missing mass is called Dark Matter.

STAR CREATION

The way in which stars form from interstellar dust is at the stage of theories and good guesses rather than certainty. Do many stars form which later accrete, or does one big one form straight away? Small Stars (not yet burning) would contribute to dark matter; the process may predict planet formation if understood.

THE SUN

The process of fusion : 4 p¹ He, produces a stream of neutrinos from the Sun, neutrinos easily pass through the Sun and the Earth. The number of neutrinos can be easily predicted from the Suns brightness (rate of energy production). Only one third of the necessary flow of neutrinos have ever been detected.

COMETS

There may be as many as 10¹² comets in orbit about the Sun. It would be useful to be able to predict future collisions with the Earth.

SUPERNOVA

It would be useful to be able to predict which stars are likely to become Supernova. If a Supernova occurred within 1000 light years of Earth, the UV and rays could destroy the ozone layer with possibly disastrous consequences for life on Earth.

PLANETARY SYSTEMS

No normal star with a Planetary system has ever been found, apart from the Sun. However, viewed from a distance, a planet the size of Jupiter would reduce the Suns luminosity by 1% if it passed in front of the Sun. This could be observed with the robotic telescope given a long series of images of the same Star and the luck that such a planet transits in front of the star during an observation.

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The EIA Team / Tel:+44 (0)1274 384070 / 25 Sept 1995