Hi All,
Thought this may be of interest, How bright the Milky way is and how strong the Rado Spectrum signals are looking towards the centre of our Galaxy, Sagittarius (Sag.A a radio source), The chart shows the very powerful emissions (syncrotron continuum at 650 Mhz. in this case) of 1248 Jy., I took this strip chart a few years back (before UHF TV became overpowering) of the Sky from 9 Hrs. to 20 Hrs. RA Dec. of -28 Deg, using a Ph.Sw. Interferometer & 2 x 20 foot stressed parabolic antennas (all homebrew) obtained signals down to 2 Jy. (like imaging a Mag.16 object) which was fantastic, cant do it now too much RFI, but the nice small arperture of Scopes and Cameras do a mighty job visually, Pix of Milky Way 1 x 10 Min. at ISO800 guided (taken last year).
cheers.....Jim
Last edited by FOOTPRINT; 05-02-2006 at 03:17 PM.
Reason: added information
That's impressive Jim. Have you got any photos of the homebrew antennas?
Can you provide some more details on how you combine the signals. I thought interferometry would be beyond an amateur - I'm very happy I was wrong! Too bad about the RFI.
Are the antennas steerable or do you just let the sky drift by?
WOW, thats great stuff Jim can you explain to me what the blips on the far left and right of the chart are. Also what other objects can you 'image' with a back yard radio telescope?
Hi Mickoking & Adam,
Ive scanned a photo of the Antennas,(attd. herewith) There were at this time 4 of them 2 x 12 foot and the 2 x 20 foot stressed parabolics, I built the 12 foot ones to test the idea, they worked so well I went bigger and built the 20 footers, An interferometer is not difficult to build, and recording is quite easy, but space for large antennas is sometimes hard to find, They were arranged to do a "Drift Scan" using the earths rotation, and were only moved in declanation, and yes any object in space can be recorded (that emits continuum or thermal radiation), The vertical defelections are the strength of the sources, the time between sources = distance, RA time is marked at the botton of the chart, Detecting Galactic Neutral Hydrogen at 1420.405 Mhz. is much easier and requires less equipment,
If you are interested I can go into this a depth, if you think its the right forum.
Hi Mickoking & Adam,
Ive scanned a photo of the Antennas,(attd. herewith) There were at this time 4 of them 2 x 12 foot and the 2 x 20 foot stressed parabolics, I built the 12 foot ones to test the idea, they worked so well I went bigger and built the 20 footers, An interferometer is not difficult to build, and recording is quite easy, ..............
If you are interested I can go into this a depth, if you think its the right forum.
regards...................Jim
G'day Jim
send me some construction details
I'm very keen to build 2 1.42 GHz antennas on my property
could then link together for a VLA for detailed point sources
Last edited by GrampianStars; 08-02-2006 at 05:43 PM.
Hi Rowena,
Yes the light & Radio spectrum pollution is getting bad here, only to get worse shortly with all the new building, I live right on the coast and can image objects as they rise over the sea in still dark skys, nothing big built on FI as yet, only Kingfisher and its far enough away.
Robert,
Ill scan some info. on the antenna construction for you and send it as a PM, do you intend to do Interferometery or Galactic Neutral Hydrogen recording.
..............
Robert,
Ill scan some info. on the antenna construction for you and send it as a PM, do you intend to do Interferometery or Galactic Neutral Hydrogen recording.
cheers...Jim
G'day Jim
Due to many unsuitable nights for optical study,
( I've been interested in radio astronomy for years ),
The antenna project is for observing and study of
the natural 1420 MHz radio emissions of neutral hydrogen atoms found throughout space.
Your antenna's design would fit the bill nicely as I cant find a supplier of used satellite TV antenna.
can you explain to me what the blips on the far left and right of the chart are. Also what other objects can you 'image' with a back yard radio telescope?
