3 ms·

When I have the time, I'd like to build an antenna to try to pick up the hydrogen line from space. Just that simple thing is so strange to me, that with a hand

When I have the time, I'd like to build an antenna to try to pick up the hydrogen line from space. Just that simple thing is so strange to me, that with a handful of components you can listen to the cosmos. I really wish science classes would have included that sort of thing.

xnx 2y ago
> that with a handful of components you can listen to the cosmos Tuning an analog radio or TV between stations also accomplishes this in a more abstract way.
- tocs3 2y ago
  Could tuning several analog radio receivers between station be used in some sort of synthetic aperture telescope?
  - Y_Y 2y ago
    Sounds a bit like Lofar. Stick a few hundred antennas into a field, collect all the raw data, and then do some herculean signal processing and you end up with a fantastic radio telescope that you can "point" retrospectively, e.g. to look at something that just happened in the gamma, before it happened (on a scale of seconds). https://www.astron.nl/telescopes/lofar/ https://www.astron.nl/telescopes/lofar/
  - dekhn 2y ago
    yes, but in an inefficient way, similar to how large clusters with ECC are weak cosmic ray detectors.
semi-extrinsic 2y ago
FYI, an antenna for the 21 cm line can be extremely low effort: https://spaceaustralia.com/news/diy-radio-telescope-sees-first-light https://spaceaustralia.com/news/diy-radio-telescope-sees-fir...
- bloopernova 2y ago
  Unfortunately I'm in the middle of moving, but once I'm done with that, I'll give this a try :)
IrishJourno 2y ago
You're in luck! David Schneider, the author of this piece, also built a $150 hydrogen line antenna for us, based on a TV tuner SDR: https://spectrum.ieee.org/track-the-movement-of-the-milky-way-with-this-diy-radio-telescope https://spectrum.ieee.org/track-the-movement-of-the-milky-wa... :)
- bloopernova 2y ago
  Unfortunately I'm in the middle of moving, but once I'm done with that, I'll give this a try :)

xnx 2y ago

> that with a handful of components you can listen to the cosmos Tuning an analog radio or TV between stations also accomplishes this in a more abstract way.

tocs3 2y ago
Could tuning several analog radio receivers between station be used in some sort of synthetic aperture telescope?
- Y_Y 2y ago
  Sounds a bit like Lofar. Stick a few hundred antennas into a field, collect all the raw data, and then do some herculean signal processing and you end up with a fantastic radio telescope that you can "point" retrospectively, e.g. to look at something that just happened in the gamma, before it happened (on a scale of seconds). https://www.astron.nl/telescopes/lofar/ https://www.astron.nl/telescopes/lofar/
- dekhn 2y ago
  yes, but in an inefficient way, similar to how large clusters with ECC are weak cosmic ray detectors.

semi-extrinsic 2y ago

FYI, an antenna for the 21 cm line can be extremely low effort: https://spaceaustralia.com/news/diy-radio-telescope-sees-first-light https://spaceaustralia.com/news/diy-radio-telescope-sees-fir...

bloopernova 2y ago
Unfortunately I'm in the middle of moving, but once I'm done with that, I'll give this a try :)

IrishJourno 2y ago

You're in luck! David Schneider, the author of this piece, also built a $150 hydrogen line antenna for us, based on a TV tuner SDR: https://spectrum.ieee.org/track-the-movement-of-the-milky-way-with-this-diy-radio-telescope https://spectrum.ieee.org/track-the-movement-of-the-milky-wa... :)

bloopernova 2y ago
Unfortunately I'm in the middle of moving, but once I'm done with that, I'll give this a try :)