A pair of noted space thinkers have resigned from an international body in protest at plans to send out powerful radio signals to alien civilisations. The two men feel that the risks of contact with extraterrestrials - who would need to be much more technologically advanced than humanity in order to visit us - have not been adequately considered.
The signalling that lies behind the concern is so-called "active SETI" (SETI meaning the Search for Extra Terrestrial Intelligence). Ordinary SETI efforts typically involve using radio telescope arrays to listen for signals sent out by aliens. With active SETI, however, the idea is to beam out powerful signals from Earth, with the idea of attracting aliens' attention.
As one might expect of the human race, there isn't any coherent global international policy on active SETI. Essentially, anyone who can afford the kit can merrily beam out any signal they feel like, even if it says "come and have a go if you think you're hard enough," or similar.
In fact, nobody seems to be doing that; but there are already some organisations sending out signals of one kind and another, hoping to get the attention of powerful alien civilisations. An acrimonious debate has been underway for some time among scientists, astronomers and other people in the field as to whether this is a good idea.
Those against active SETI have been getting angrier in recent years. One such is Michael Michaud, a former career US diplomat who became Deputy Assistant Secretary of State for Science and Technology. He has been involved in international agreements and negotiations around the area of SETI for years, in particular as a member of the International Academy of Astronautics (IAA) SETI study group.
"Let’s be clear about this," wrote Michaud in 2005.
"Active SETI is not scientific research. It is a deliberate attempt to provoke a response by an alien civilization whose capabilities, intentions, and distance are not known to us. That makes it a policy issue."
Michaud says that any active SETI efforts should be thought through in advance by the assembled governments of the world, rather than anyone who can get access to powerful transmitting equipment. He quotes renowned brainbox and futurologist Freeman Dyson as saying that:
"It is just as unscientific to impute to remote intelligences wisdom and serenity as it is to impute to them irrational and murderous impulses. We must be prepared for either possibility ..."
Given that the human race lacks any serious space defences, the only preparation against possibly homicidal ET visitors is to avoid being spotted in the first place.
Michaud's concerns are shared by Dr John Billingham, former chief of the NASA SETI office. The Times reports that he and Michaud have resigned from the IAA study group in frustration after active-SETI people refused to consider turning off their signals.
“We’re talking about initiating communication with other civilisations, but we know nothing of their goals, capabilities or intent,” Billingham told the Times.
It seems that Alexander Zaitsev of the Moscow Institute of Radio Engineering - to name just one - is merrily beaming out high-intensity messages to nearby star systems using a Crimean radio-telescope, and he's not willing to stop because Michaud and Billingham say so.
Some would argue that humanity already emits so much radio that the debate is academic, as we will already have been spotted if we're going to be. An example of this is the Arecibo radar telescope, famous to many as the scene of a James Bond dustup in the early Brosnan flick Goldeneye. Arecibo gets used for passive SETI and other listening-type astronomy for much of the time, but it also has a very powerful active-radar mode used to track various celestial bodies in our home solar system. Most of the Arecibo radar emissions beam on out into deep space, perhaps giving away the location of humanity's only sanctuary to murderous interstellar conquerors.
As an example, the people at the Allen Telescope Array - a new, dedicated SETI detection rig built with the aid of $25m from zany Microsoft megawealth figure Paul Allen - reckon that if another race were fooling about with an Arecibo-type setup, they could spot it 1,000 light-years away.
Quite frankly, this whole business sounds like ample justification for a huge atomic space battlefleet coupled with aggressive efforts at interstellar colonisation (so that someone will be left after the Earth gets blown up or conquered as a prelude to us all being eaten/enslaved/impregnated with disgusting alien larvae etc). The argument seems quite compelling to us here on the Reg space-battlefleet & interstellar-colonisation desk, anyway. Others may not be so convinced, remaining focused on their parochial concerns about global warming, ignorance among the young people of today, beer prices etc. (We believe it should go without saying that the space battlefleet costs not involve any increase in alcohol tax.)
The Times report is here.®