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SETI: A celebration of the first 50 years
April 2010

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The search for radio signals from beings on other worlds reaches its half century this April. Over the last fifty years, the Search for Extraterrestrial Intelligence has surveyed many thousands of stars; in that time we have encountered new worlds around other planets, learnt more about how life may have arisen on Earth, and conditions possibly suitable for primitive life elsewhere in the Solar System, but we have yet to hear from other life forms amidst the stars. Are they out there, somewhere, undetected, or as the physicist Enrico Fermi feared, is there no one out there at all? The anniversary of SETI is the ideal opportunity to assess its progress, explore some of its ideas, and find out how close we are to answering the question, are we alone?

1. The Quest

The search for radio signals from beings on other worlds reaches its half century this April. In the first of many articles to celebrate this milestone, Keith Cooper introduces SETI and explores our desire to find life elsewhere in the Universe.



2. The state of the art

Fifty years ago this April, radio astronomer Dr Frank Drake embarked on Project Ozma, the first ever attempt to detect the technological signature of intelligent creatures on planets orbiting stars other than our Sun. This was the first step along a path that one day may culminate with our realising that humanity is part of a galactic culture of intelligent life, scattered across the light years between the stars.



3. Power to the people

Fancy being the one to make history and discover extraterrestrial intelligence? It’s not as far-fetched as it sounds. Citizen science, facilitated by increasing computer power and technologies on the Internet, is fast become the buzzword in areas of groundbreaking research. Now Dr Jill Tarter of the SETI Institute plans to take citizen science one step further with the launch of setiQuest, a project that will enable members of the public to not only visually search radio observations for anomalous transmissions, but also to create new computer algorithms and methods to analyse the data, potentially altering the way the search is conducted.



4. Lighting the way –
optical SETI

In celebrating the half century of SETI, we should not forget that the laser, too, is fifty years old this year. It is somewhat fitting that the technology of lasers has since converged with the search for extraterrestrial intelligence.



5. The water hole

For oxygen breathing, water-drinking carbon-based life forms such as ourselves, space is a barren desert, with vast stretches of unbearable nothingness between the oases of life that we are searching for.



6. Cosmic Call

Despite fifty years of searching, there is still no sign of little green men. SETI researchers will point out that if the Galaxy were an ocean, we’ve searched the equivalent of a beaker’s worth of water. The cynical suggest that the reason we’ve not found anyone is because there is nobody out there. It’s a depressing thought, but there are alternatives.



7. Terminating the transmission

Messaging Extraterrestrial Intelligence (METI, sometimes called Active SETI), is much like diving into a party and making your presence felt. However, a core group of SETI scientists forcefully argue that we should not be shouting into the jungle, that we shouldn’t be looking to strike up a conversation with strangers whose motivations and capabilities are completely unknown to us.



8. The Drake Equation

How many advanced extraterrestrial civilisations are there in our Galaxy? Some critics argue that you might as well ask how many angels can dance on the point of a needle, but Frank Drake thinks otherwise. The SETI pioneer’s famous equation seeks an answer to that question and although it has proven controversial over the years, Drake still stands by it and it continues, rightly or wrongly, to form the heart of our estimates about ET.



9. The Drake Equation: Planets

Life as we know it needs a planet to live on. With over 450 exoplanets currently known we take it for granted that there are planets out there, orbiting other suns, but it is all too easy to forget that back in 1960, there were no planets known beyond our Solar System. That other planets existed was a huge assumption based on no evidence whatsoever.



10. The Drake Equation: Life

Life is a mystery, and if we can understand how and why life developed on Earth, we’ll be in a better position to appreciate whether it could happen somewhere else, too.



11. The frugal alien's beacon

August, 15 1977: a pulse of radio waves at 1,420MHz radiates down from space to be received by the Big Ear radio telescope in Ohio for 72 seconds. Then: nothing. Sporadic searches of the area since have failed to find this interstellar radio chorus. It’s origins remain a mystery.



12. SETI pushes ahead

As Mark Twain might have said, the reports of SETI’s death are greatly exaggerated. As a key instrument in SETI, the Search for Extraterrestrial Intelligence, the Allen Telescope Array (ATA) has hit the buffers. A network of forty-two 6.1-metre radio dishes at Hat Creek in northern California, run by the SETI Institute and the University of California, Berkeley, the ATA was placed into ‘hibernation’ in April and staff laid off as funding to maintain its operation dried up in the California sunshine. The media proclaimed the end of SETI, but a new survey of planets discovered by NASA’s Kepler spacecraft is showing that there is life beyond the ATA.



13. Detecting ET’s city lights

A pair of researchers from the Harvard–Smithsonian Center for Astrophysics and Princeton University have developed a new means by which, in the future and with the requisite telescopic power, it may be possible to detect artificial lights from cities on other planets inhabited by extraterrestrial intelligence. In the meantime, say Professors Abraham Loeb and Edwin Turner, the technique can be put to the test by searching for artificially illuminated objects in our own Kuiper Belt.



The Planets
From tiny Mercury to distant Neptune and Pluto, The Planets profiles each of the Solar System's members in depth, featuring the latest imagery from space missions. The tallest mountains, the deepest canyons, the strongest winds, raging atmospheric storms, terrain studded with craters and vast worlds of ice are just some of the sights you'll see on this 100-page tour of the planets.

Hubble Reborn
Hubble Reborn takes the reader on a journey through the Universe with spectacular full-colour pictures of galaxies, nebulae, planets and stars as seen through Hubble's eyes, along the way telling the dramatic story of the space telescope, including interviews with key scientists and astronauts.

3D Universe
Witness the most awesome sights of the Universe as they were meant to be seen in this 100-page extravaganza of planets, galaxies and star-scapes, all in 3D!


© 2014 Pole Star Publications Ltd.