Want to stay on top of all the space news? Follow @universetoday on TwitterIt is probably the most seductive urge for mankind: search for extraterrestrial life. There are many ways to look for life; from digging into the Martian dirt with robotic landers looking for pre-biotic compounds, to building vast radio antennae to “listen” out for distant communications either leaked or transmitted deliberately from a distant star system from a developed, intelligent civilization. However, despite our best efforts, we appear to be the only form of life for hundreds of lightyears around. It is eerily quiet out there…
Although we appear to be drawing blanks so far, it doesn’t stop us from trying to work out what we should be looking for. In the quest to find a vastly advanced alien civilization, a forthcoming Russian space telescope hopes to bridge the gap between science fiction and science fact, attempting to find evidence (or lack thereof) of observable attempts of astroengineering by an alien race…
New and exciting ways are being formulated to work out whether intelligent life does exist beyond our blue oasis. Programs such as the famous Search for Extra-Terrestrial Intelligence (SETI), Messaging to Extra-Terrestrial Intelligence (METI) and the tongue-in-cheek Wait for Extra-Terrestrial Intelligence (WETI) are conceived to somehow interact with a sufficiently advanced alien culture (one that has the ability to communicate via radio, at least). In an engrossing entry I read in last week’s Carnival of Space Week 86, Dr Bruce Cordell (21st Century Waves) discussed the apparent paradox between UFOs and Fermi’s Paradox (in a nutshell: if aliens have visited our planet, as UFO sightings would lead us to believe, why haven’t we intercepted any kind of signal via SETI?). I was most interested with Cordell’s thoughts on optical communications that could be used by extraterrestrials to communicate with a pre-radio communication human era. Apparently, in 40 years, mankind could be generating very bright signals using 30 terrawatt optical beacons for pre-radio civilizations to see over 10 light years away, brighter than their brightest star. If there are advanced civilizations out there, why have we not seen their optical transmissions?
To summarize, we are a little confused by the lack of life in our Universe (intelligent life in any case).
So, perhaps we can find other ways to spy on our hypothetical alien neighbours. Could we build a powerful telescope to seek out structures built by alien civilizations? Possibly, according to a forthcoming Russian space-based telescope project: The Millimetron Space Telescope.
On reading an article about this subject on the Daily Galaxy, I thought I’d heard of something like this before. Sure enough, during my research on the Infrared Astronomical Satellite, IRAS (surrounding the whole Planet X controversy), I found out that work was being done to try to find the infrared signature of the hypothetical Dyson Sphere. The Dyson Sphere is a theorised example of an astroengineered structure by a significantly advanced alien race. There are many variations on this theme, including science fiction ideas of an engineered “ring” straddling a host star (as pictured top). In the case of the Dyson Sphere, this megastructure would generate infrared radiation, and analysis of IRAS data has been done to establish an upper limit on the existence of these objects. So far, no Dyson Sphere candidates have been found (within 300 light-years from Earth in any case).
To build on the IRAS survey, in 2017, Russia hopes to launch the Millimetron to observe distant stellar systems in millimeter, sub-millimeter and infrared wavelengths. This instrument has a long list of aims, but one of the extreme results that could come from this project is the detection of astroengineered megastructures.
The goal of the project is to construct space observatory operating in millimeter, sub-millimeter and infrared wavelength ranges using 12-m cryogenic telescope in a single-dish mode and as an interferometer with the space-ground and space-space baselines (the later after the launch of the second identical space telescope). The observatory will provide possibility to conduct astronomical observations with super high sensitivity (down to nanoJansky level) in a single dish mode, and observations with super high angular resolution in an interferometric mode. – The Millimetron Project.
By combining the orbiting telescope with observatories on the ground, it may be possible to create a very long baseline interferometer (VLBI) with huge baselines beyond 300,000km. This will provide unprecedented angular resolution. Alone, the large 12 metre dish will allow astronomers to probe emissions at the nano-Jansky level, where radio astronomers usually operate from <1-100 Janskys (the Jansky is a non-SI measurement of electromagnetic flux density).* With a system like this, very weakly radiating sources may be detected, possibly revealing structures such as the Dyson Sphere, or possibly sci-fi concepts like Larry Niven’s “Ringworld”.
Although I am dubious as to whether our persistent efforts to find intelligent extraterrestrial life will ever turn up positive, the search is exciting and certainly boosts the scientific process in directions we wouldn’t have necessarily examined…
*Thanks to Don Alexander for tightening up a couple of points in this article