lancaster university department of communication systems skymap at 38.2 mhz as measured by iris...
TRANSCRIPT
![Page 1: Lancaster University Department of Communication Systems Skymap at 38.2 MHz as Measured by IRIS Steve Marple](https://reader035.vdocuments.us/reader035/viewer/2022062719/56649eec5503460f94bfd4fa/html5/thumbnails/1.jpg)
Lancaster University
Department of Communication Systems
Skymap at 38.2 MHz as Measured by IRIS
Steve Marple
![Page 2: Lancaster University Department of Communication Systems Skymap at 38.2 MHz as Measured by IRIS Steve Marple](https://reader035.vdocuments.us/reader035/viewer/2022062719/56649eec5503460f94bfd4fa/html5/thumbnails/2.jpg)
Lancaster University
Department of Communication Systems
Skymap
A skymap is a map of cosmic noise level in all directions.
• Required to generate theoretical quiet day curves* (QDCs) for riometry and system design
• Uses in astronomy, e.g., observing large-scale galactic features
* QDC: background cosmic noise level in absence of absorption.
![Page 3: Lancaster University Department of Communication Systems Skymap at 38.2 MHz as Measured by IRIS Steve Marple](https://reader035.vdocuments.us/reader035/viewer/2022062719/56649eec5503460f94bfd4fa/html5/thumbnails/3.jpg)
Lancaster University
Department of Communication Systems
Skymap [Cane, 1978]
0.2 0.4 0.6 0.8 1
30
210
60
240
90 270
120
300
150
330
180
0
15
20
25
30
35
40
45
50
55
Temperature (1000’s K)
![Page 4: Lancaster University Department of Communication Systems Skymap at 38.2 MHz as Measured by IRIS Steve Marple](https://reader035.vdocuments.us/reader035/viewer/2022062719/56649eec5503460f94bfd4fa/html5/thumbnails/4.jpg)
Lancaster University
Department of Communication Systems
Jodrell Bank Radio Telescope
Kilpisjärvi
Jodrell Bank
Lindau
![Page 5: Lancaster University Department of Communication Systems Skymap at 38.2 MHz as Measured by IRIS Steve Marple](https://reader035.vdocuments.us/reader035/viewer/2022062719/56649eec5503460f94bfd4fa/html5/thumbnails/5.jpg)
Lancaster University
Department of Communication Systems
IRIS (Imaging Riometer for Ionospheric Studies)
• 64 crossed dipoles• 49 imaging beams• beam width 13° ~ 16°• 6+ years of data• Declination range:
14.1° - 83.3°N
![Page 6: Lancaster University Department of Communication Systems Skymap at 38.2 MHz as Measured by IRIS Steve Marple](https://reader035.vdocuments.us/reader035/viewer/2022062719/56649eec5503460f94bfd4fa/html5/thumbnails/6.jpg)
Lancaster University
Department of Communication Systems
Beam projection
12oE
16oE 20oE 24oE 28oE
66oN
67oN
68oN
69oN
70oN
71oN
72oN
![Page 7: Lancaster University Department of Communication Systems Skymap at 38.2 MHz as Measured by IRIS Steve Marple](https://reader035.vdocuments.us/reader035/viewer/2022062719/56649eec5503460f94bfd4fa/html5/thumbnails/7.jpg)
Lancaster University
Department of Communication Systems
Received power affected by:
• Solar controlled D-region absorption
• Snow (modifies antenna performance)
![Page 8: Lancaster University Department of Communication Systems Skymap at 38.2 MHz as Measured by IRIS Steve Marple](https://reader035.vdocuments.us/reader035/viewer/2022062719/56649eec5503460f94bfd4fa/html5/thumbnails/8.jpg)
Mean QDC Power and Snow Depth00:00:00 UT 02/09/1994 - 00:00:00 UT 01/01/2001
Kilpisjärvi, Finland (69.05° N, 20.79° E)
-110.5
-110
-109.5
-109
Po
we
r (d
Bm
)
1/1/1995 1/1/1996 1/1/1997 1/1/1998 1/1/1999 1/1/2000 1/1/20010
0.5
1
1.5
2
date
Sn
ow
de
pth
(m
)
![Page 9: Lancaster University Department of Communication Systems Skymap at 38.2 MHz as Measured by IRIS Steve Marple](https://reader035.vdocuments.us/reader035/viewer/2022062719/56649eec5503460f94bfd4fa/html5/thumbnails/9.jpg)
Lancaster University
Department of Communication Systems
IRIS Skymap
![Page 10: Lancaster University Department of Communication Systems Skymap at 38.2 MHz as Measured by IRIS Steve Marple](https://reader035.vdocuments.us/reader035/viewer/2022062719/56649eec5503460f94bfd4fa/html5/thumbnails/10.jpg)
Lancaster University
Department of Communication Systems
Cane and IRIS skymaps
0.2 0.4 0.6 0.8 1
30
210
60
240
90 270
120
300
150
330
180
0
15
20
25
30
35
40
45
50
55
Temperature (1000’s K)
![Page 11: Lancaster University Department of Communication Systems Skymap at 38.2 MHz as Measured by IRIS Steve Marple](https://reader035.vdocuments.us/reader035/viewer/2022062719/56649eec5503460f94bfd4fa/html5/thumbnails/11.jpg)
Lancaster University
Department of Communication Systems
Summary
• Sky maps are needed for theoretical quiet day curves and system design
• An imaging riometer has been used as a radio telescope to produce a skymap
• Using riometer data from Antarctica a matching southern hemisphere map could be made
![Page 12: Lancaster University Department of Communication Systems Skymap at 38.2 MHz as Measured by IRIS Steve Marple](https://reader035.vdocuments.us/reader035/viewer/2022062719/56649eec5503460f94bfd4fa/html5/thumbnails/12.jpg)