Advertisement
If you have a new account but are having problems posting or verifying your account, please email us on hello@boards.ie for help. Thanks :)
Hello all! Please ensure that you are posting a new thread or question in the appropriate forum. The Feedback forum is overwhelmed with questions that are having to be moved elsewhere. If you need help to verify your account contact hello@boards.ie
Hi there,
There is an issue with role permissions that is being worked on at the moment.
If you are having trouble with access or permissions on regional forums please post here to get access: https://www.boards.ie/discussion/2058365403/you-do-not-have-permission-for-that#latest

Light from alien cities could signal intelligent life out there

  • 05-11-2011 1:51pm
    #1
    Capt'n Midnight
    Moderators, Recreation & Hobbies Moderators, Science, Health & Environment Moderators, Technology & Internet Moderators Posts: 93,567 Mod ✭✭✭✭


    http://www.irishtimes.com/newspaper/frontpage/2011/1105/1224307107470.html
    ASTRONOMERS HAVE come up with a new way to search for advanced life on distant planets: look for the light given off by their cities. This could help us pinpoint intelligent extraterrestrials.
    ...
    The astronomers point out, however, that if there is an advanced civilisation out there making use of radio technology, then the signal this technology bounces out into space may be getting weaker. This is happening on Earth, Loeb and Turner say. As technology changes our own radio signal is fading.

    Except for one slight detail.

    RADAR

    AFAIK In the GHz band we are the brightest thing in the solar system.

    http://www.swri.org/4org/d10/comm/commeng/mts.htm
    The AN/FPS-85 (a computer-controlled, phased-array radar) searches, detects, identifies, and tracks satellites and other space objects. Built in the 1960s, this unique high-power radar is at Eglin Air Force Base in Florida.

    The AN/FPS-85 radar incorporates separate transmitter and receiver arrays operating at 442 MHz. The Transmitter Array System is composed of 5,184 radar transmitter units arranged in a 72-square matrix. Each radar transmitter unit delivers nearly 10 kilowatts of peak power into a dipole antenna yielding a collective beam peak power of more than 30 Megawatts.

    The Russian woodpecker and similar over the horizon radars also chuck out multiple megawatts as do those used shipboard for the aegis system and on carriers.

    Unlike light Radar usually has a specific wavelength and a periodic signal unlikely to be confused with an aurora.



    Also how could the light be distinguished from moonshine ?
    Full Moon gives 1 Lux , surburban landscape is about 5 Lux but over a tiny fraction of the area .


    The Russians have done work on space mirrors, which could offer another way to reduce communal lighting costs while being indistinguishable from a moon. ET may have use this too.


Advertisement