is surely the most spectacular telescope on Earth and definitely worth a family visit to the visitor centre at Jodrell Bank near Macclesfield in Cheshire. Remarkably it can tip all the way down to to the horizon and if you can get close to it you can watch its wheels very slowly turn as it follows a radio source across the sky. In other words you can see the Earth actually turn — which fascinated me when I was privileged to observe with it.
The 250 foot Lovell Radio Telescope completed in 1957 and named after Sir Bernard Lovell of Manchester University who built her largely out of war surplus, is still the only big dish which can tilt all the way down to the horizon. She has numerous scientific discoveries to her credit including gravitational lenses.
The old girl’s getting on a bit but she’s definitely had her moments. The first pictures back from the Moon’s surface, taken by the Russian Luna 2 spacecraft in 1966, were beamed back to Earth using her unique capabilities at the time. The local Manchester University staff decoded them and rushed them down to a Royal Astronomical Society meeting in London where I was lucky enough to be amongst the audience as a student. We all had to pinch ourselves to make sure we weren’t dreaming.
Much later in 2004 my colleague Jon Davies and his team used it to discover a Hydrogen source Virgo HI 21 in the Virgo Cluster, which is, in my opinion, the first Dark Galaxy. It’s massive, it’s spinning and it’s invisible. What else could it be?
The source Virgo HI 21 first discovered by a team from Cardiff University who were searching for Dark Galaxies in the 21-cm Hydrogen Line using a multi-beam receiver specially designed for that purpose. Higher resolution radio observations by the same team with the radio interferometer at Westerbork in Holland are shown above superposed on negative optical images. On the left you can see that the source has interacted with and disturbed the massive Spiral Galaxy NGC 4254, the most luminous in the huge cluster. The velocity map on the right reveals that Virgo HI 21 is spinning at about 200 kilometres a second, about what you would expect of a massive disc. But very deep Hubble Space Telescope images of the mysterious disc revealed no light.
The claim that Virgo HI 21 is a Dark Galaxy gave rise to titanic refereeing battles and vicious arguments which are described in Chapters 12 and 13 of my novel ‘Beyond the Western Stars.’ [ which is described here under Category ‘My Books’]. They illustrate that cutting edge astronomy is definitely not for the faint hearted. If you ask me, from a distance of 12 years, much of the opposition was motivated by sour grapes. But why not make up your own mind and look at some of the evidence. Science can be tough, very tough.
Tags: hidden galaxies, my books, scientific method, telescopes
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