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I’m very pleased to announce that I will be giving a talk at this year’s Herstmonceux Astronomy Festival, held at the famous Herstmonceux observatory in Sussex. The subject of my talk will be the science behind the Hubble Space Telescope’s greatest images. I’m very excited about speaking at the festival and a little daunted at the same time as the other speakers are all very highly regarded astronomers. I’m sure it will be great fun though and I’m really looking forward to it. To find out more about the festival, which will be held on the 5th, 6th and 7th of September, visit the Observatory Science Centre’s website here.

Dr. Scott Chapman from the Institute of Astronomy in Cambridge has just presented the latest results from a collaboration between the MERLIN UK radio telescope array, Keck (at optical wavelengths), the VLA in the US and the Plateau de Bure submillimetre observatory in France. The results show that there was a group of galaxies in the early Universe that experienced an incredible burst of star formation about 2 billion years after the Big Bang. This phenomenal burst of activity was observed in galaxies that were shining a mere 3 billion years after the Big Bang and is thought to have been vastly more dramatic than any star formation we see nowadays.

Remarkably it was only until relatively recently that astronomers detected a similar gathering of sub-mm galaxies in the early Universe. These galaxies are particularly faint in optical wavelengths but very bright in the radio wavelengths. Instruments like SCUBA mounted on the James Clerk Maxwell Telescope (JCMT), on Mauna Kea in Hawaii could see the sky in sub-mm wavelengths and so could detect them; allowing astronomers to investigate their nature. Yet astronomers believed that these galaxies were only part of what was going on (star-forming wise) in the early Universe, because SCUBA was good at looking at relatively cooler sub-mm galaxies.

Now, these new results from the collaboration of many telescopes do indeed show a gathering of slightly warmer galaxies, not altogether different from those spied by SCUBA, undergoing dramatic star formation. The observations indicate that these galaxies are surrounded by vast clouds of gas. That gas, the astronomers argue, will keep the star formation going at a tremendous rate for “hundreds of millions of years”.

You can see images from the results and a very cool video here.

For a long time astronomers (specifically radio astronomers) have wanted to place a telescope on the Moon. Now it seems that that desire is slowly becoming a possibility. NASA recently announced how it was backing a series of studies to investigate potential experiments for its ‘Next Generation Astronomy Missions’. Included in that backing is one proposal from the Massachusetts Institute of Technology to build a small radio telescope array on the Moon’s far-side.

Radio telescopes are really important tools for probing the Universe. All sorts of objects emit radio waves; quasars, very hot gas in the space between the stars, electrons rapidly whirring around in magnetic fields as well as planets to name but a few. On Earth radio astronomy has been at the forefront of astronomical research for decades. Indeed many of the great discoveries of modern astronomy have been made thanks to the use of radio telescopes; for example the radio telescope (MK1A) at Jodrell Bank Observatory in the UK discovered the first gravitational lens amongst its many great accomplishments.

But there is a problem with doing radio astronomy from Earth. Radio signals from astronomical objects are extremely faint; something that makes observing radio sources tricky even on a good day. But radio waves, of course, don’t just come from the sky. Radio stations, satellites, Wi-Fi networks and many other man-made sources all emit vast amounts of radio waves that are much more powerful than those coming from space. With this ubiquitous fog of radio waves often ’spilling’ into the frequencies that astronomers observe in (combined with the fact that the Earth’s ionosphere blocks certain radio signals) it’s a wonder we can observe anything emitting radio waves in space; sorting the proverbial radio wheat from the chaff is no easy task.

What radio astronomers really need is something to block all the ‘noise’ coming from the Earth. Something like a massive shield…something like…the Moon. By locating radio telescopes (or groups of smaller telescopes called ‘arrays’) on the lunar ‘farside’ the telescopes are hidden from the radio noise from the Earth, since the farside is always in the radio ’shadow’ of the Moon, plus they don’t have the Earth’s ionosphere to contend with!

MIT’s proposed telescope will consist of hundreds of small instruments set up across about 2 square kilometres to studio low frequency radio waves. The telescopes will be arranged by robotic machines and they don’t have to be that accurate since the wavelenghts that the array will study are fairly long. The array will probe some of the least well known periods of the Universe’s early history as well as looking at space-weather from the solar wind, radio emissions from the planets and possibly even galaxies too.

I’m going to be talking to Dominic King live on BBC Radio Kent at 10:30am tomorrow morning about the ambitious plans for these lunar observatories so if you are in south-east England tune in!

Above: ‘Farside’ radio telescopes will be able to tell us more about periods in the early Universe, earlier than the HUDF (pictured).
Credit: NASA, ESA, and S. Beckwith (STScI) and the HUDF Team

This is great news. Though as Johnathon Amos reports in his BBC online article we are going to have to wait a while to see what this means now for the STFC budget.