Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!

 



Forgot your password?
typodupeerror
Space Science

Prototype Telescopes Complete Key Test 78

Posted by CowboyNeal
from the if-this-trend-continues dept.
Matthew Sparkes writes "Two prototype antennas for the world's largest array of millimeter-wave telescopes have passed a key test, working to track and image Saturn for more than an hour. Ultimately, ALMA (Atacama Large Millimeter/submillimeter Array) is expected to resolve details 10 times finer than the Hubble Space Telescope when it is completed in 2012."
This discussion has been archived. No new comments can be posted.

Prototype Telescopes Complete Key Test

Comments Filter:
  • Will they.. (Score:2, Interesting)

    by Creepy Crawler (680178) on Saturday March 10, 2007 @12:19PM (#18300490)
    Censor the raw data coming from out of this too, like they have with the Hubble?

    I'm a ham operator, and the signals coming from the Hubble are a jumbled mass of unintelligible garble. Further research shows they are using military hardware for secure connections.

    I do understand that control codes are administered via ground, however, public key signing would allow transparency while providing a secure platform.

    Why do they hide the whole data stream? What do they not want us to see?
  • by N3wsByt3 (758224) <NewsbyteNO@SPAMfreenethelp.org> on Saturday March 10, 2007 @12:32PM (#18300568) Homepage Journal
    I'm actually beginning to wonder if space-telescopes still have their use (in regard to costs/benefits). I mean, thanks to interferometry one can get the resolution (equal or better) with earth based telescopes for a fraction of the price of space-telescopes like hubble and consorts. And thanks to adaptive optics there is hardly any atmospheric blurring which smears out the pictures anymore, neither. And, since the mirrors can be bigger then those send into space, the light-gathering power is way superior for earth-based telescopes.

    The only advantages left are for specific wavelengths (like near-infrared), because the atmosphere absorbs most of that, but even that is more and more debatable, now that new instruments and detectors are becomming so sensitive that they can detect and use it on Earth too. I'm wondering, with the multi-billion costs of space-telescopes, if it's really worth the money? With the same amount of money, one could make a huge interferometer-telescope with a diameter of the Earth (though it would need to consist out of many 10-meter telescopes for light-gathering purposes). I'm all for space-exploration, but what still justifies the expense of a space-telescope, if earth-bound ones can do as well for a fraction of the price?

  • by Anonymous Coward on Saturday March 10, 2007 @01:04PM (#18300748)
    One point to consider. Radio-frequency and ligth polution. If you look at a map from the earth at nigth
    you see almost no free spot in the northern hemisphere for an optical telescope. Also, radio-frequency polution
    will give the VLA and similar a hard time in years to come. This could be justification to go to space
    (maybe the moon?). So far, Chile is the best place to put a telescope.
  • by Creepy Crawler (680178) on Saturday March 10, 2007 @01:05PM (#18300756)
    ---I have no problems believing that the control data is encrypted for the hubble. For one thing, you don't want others taking it over.

    No, of course you dont want some random joe to take Hubble over. However, they could implement in which "packets" are signed. The data would be separate from the authenticated signature. Along with that, they would want to implement a proper timecode to prevent replay attacks.

    But controlling is aside the issue.

    And I do hate to mince words but "normal HAM operator"... There isnt such a thing as a normal ham operator these days. Many hams specialize in one or two distinct fields of RF study. I like examining digital commms and remote communications (EME and meteor scatter).Along with my interests, I have bought that A/D board recommended by GnuRadio (normal HAM operator). All I needed was a RF front end and just to downsample to the range of the AD board (0-20 MHz).

    I asked for help from some people at NASA and they said the connection was encrypted, and it does seem to be the case.

    It doesnt really matter what Im required to build for receiving gear. It's all multi-purpose for us hams. And I do like the idea of splitting the transmitters from the receivers (well, you do have 2 antenna then per kit).

    ---I'm not saying that you're a 'normal' Ham operator, Crawler, but we're talking the space industry here.

    Too true. No offense taken. Still, I can decode the majority of transmissions (the old freq shift Symbol cards are really neat under a scope) and can transmit on quite a few bands. I dont know if you've ever been in a Ham's shack, but the amount of gear they can have (and I too) is pretty immense. I just focus on the digital side a bit more :-) .
  • by Creepy Crawler (680178) on Saturday March 10, 2007 @01:22PM (#18300838)
    ---Hubble releases public images, but much of the research is just that - research - done by labs who are trying to maintain the integrity and proprietary nature of their work.

    I want you to realize that I am a US citizen and who pays his taxes. I speak from my American view: WHY is governmental science proprietary? Above all other things, science done by the government or by government money should be either 100% public domain, or the % of profits should be returned to the people (Im thinking of public uni's here).

    Hubble was paid for by US Citizens. I want their data open and in the clear. I dont want to vandalize or destroy. I wish to look.

    ---Hubble data is supposed to go to the researcher first and the public second. IIRC it's a default six month delay unless overridden by the lab collecting the data.

    You know, these scientists could learn something from following the model the GPL uses: collaboration. Open up the output for all to see.. Most of it's probably not much anyways... But that's the point. Let us decide.

    ---It's not censorship so much as embargo, and it's really no different from what any researcher does in order to not be scooped on the research they're doing.

    That isnt an excuse. I (in part) paid for this damned orbital telescope, and I want the output untouched by some "research group".
  • by ajpr (921401) on Saturday March 10, 2007 @01:24PM (#18300856)
    In a lot of bands you can't see anything through the atmosphere.

    Also if you are looking for chemical signitures (oxygen, methane) etc then you will have problems with the atmosphere again.

    Space also gives you 24 hour observation, obviously not possible on the earth during the day. Apart from that you get a free vaccuum which will help in keeping the instrument cool. This is useful for all observations, not just infra red (although it is particularly good for that). Ground based telescopes are more suited to microwave/radio astronomy.

    And don't forget about UV, which is impossible to see through the atmosphere (if it wasn't for the atmosphere absorption of UV we'd be having a bad case of sunburn).
  • by Cid Highwind (9258) on Saturday March 10, 2007 @05:01PM (#18302310) Homepage
    * The data is made available to everyone after a short time delay

    We *assume* that the data are made available after a short time, but because of the encryption there's no way to correlate released data with observed transmissions from HST. Some people accept NASA's word on this, others don't.

    Let me put it this way: Given the present theocratic leanings of the US government, if NASA found something that fundamentally challenged our notion of our place in the universe (like, say, one of the Mars rovers found fossil bacteria that predate any known life on Earth by a billion years or so) do you think we would ever hear about it through official channels? Or would NASA just "lose contact" with the vehicle and quietly shut down the program?

    Is getting a shot at publishing before the other scientists really that much more important than keeping the christian fundies that control the hardware and the money honest?
  • by spaceyhackerlady (462530) on Saturday March 10, 2007 @06:42PM (#18303156)

    Except that one is a radio telescope and one is an optical telescope.

    So? ALMA images the universe in different wavelengths than Hubble/Spitzer at al, but can do so at very high resolution. What really matters is how many wavelengths your aperture is. An 18 km baseline at a 1 mm wavelength is more wavelengths across than a 2.2 meter mirror at 600 nm. A lot of the highest resolution imaging is done with aperture synthesis nowadays, whether it's astronomers doing long-baseline interferometry, or using synthetic aperture radar to take pictures of the Earth.

    Some day we'll be able to optical interferometry across multi-kilometer baselines. I look forward to the results.

    ...laura

Our business is run on trust. We trust you will pay in advance.

Working...