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| photo through 5" Newtonian by Christian Wolter |
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| Observation site |
Springtime in Moenchfeld
10 years ago
Jul 11, 2012
TSE1991 Hawaii
The Big One on the Big Island - 21 years ago photo gallery
Jul 1, 2012
RZBW Inside
Guided tour inside the newly opened Raumfahrtzentrum Baden-Wuerttemberg on Jun 30, 2012
Tag der Wissenschaft, Uni Stuttgart More pics: Gallery
Vortrag Nachhaltige Energiewirtschaft: Aufbruch zu neuen Ufern!
PD Dr. Eberhard Goering, MPI für Intelligente Systeme
Charts
* Regenerativ geht und reicht in jedem Fall
* Mit dezentralem Puffer ud dezentraler "smarter Kraft-Wärmekopplung"
können wir uns Netzausbau fast schenken
Tag der Wissenschaft, Uni Stuttgart More pics: Gallery
Vortrag Nachhaltige Energiewirtschaft: Aufbruch zu neuen Ufern!
PD Dr. Eberhard Goering, MPI für Intelligente Systeme
Charts
* Regenerativ geht und reicht in jedem Fall
* Mit dezentralem Puffer ud dezentraler "smarter Kraft-Wärmekopplung"
können wir uns Netzausbau fast schenken
Jun 5, 2012
Venustransit 2012
Simulation of the Transit of Venus 2012 Jun 06 with good old Redshift 4.
Heliocentric view, 415000 km north of solar center, magnification 300x, starting at 00:30 UTC, 1 minute intervals
Heliocentric view, 415000 km north of solar center, magnification 300x, starting at 00:30 UTC, 1 minute intervals
May 20, 2012
Eclipse track and satellite images
Moon shadow recorded by Terra Satellite over the Pacific on May 20, 23:30 UT
MODIS Image of the day for May 23
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GOES West full disk views, data from "NOAA-NASA GOES Project"
http://goes.gsfc.nasa.gov/
ftp://goes.gsfc.nasa.gov/pub/goeswest/fulldisk/fullres/vis/
GOES West view at 01:30 UT
Update 01:24 UT
GOES West view at 01:00
There it is - the lunar shadow - very obvious in the animation
Series with half_hourly intervals between May 20, 21:30 UT and May 21, 01:30 UT saved here
Update 20:42 UT
Google Earth screen shots with clouds, weather, travelcams on this gallery
At the end of the eclipse track the southern region around Midland, TX appears to be in fair weather, opposed to the northern part near Amarillo.
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MODIS May 20 16:50-18:35UT, Google Earth May 21 23:19
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15:00 UT
Google Earth views of the track of the annular solar eclipse and MODIS satellite images.
May 19, 2012, 17:45-19:30, Bands 7-2-1
More to come.
View also
Near Real Time (Orbit Swath) Images
http://lance-modis.eosdis.nasa.gov/cgi-bin/imagery/realtime.cgi
MODIS Image of the day for May 23
----------------
GOES West full disk views, data from "NOAA-NASA GOES Project"
http://goes.gsfc.nasa.gov/
ftp://goes.gsfc.nasa.gov/pub/goeswest/fulldisk/fullres/vis/
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| 00:00 UT Moon shadow in upper left corner |
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| 03:00 UT |
GOES West view at 01:30 UT
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| processed with FDRTools, receptor tonemapping |
Update 01:24 UT
GOES West view at 01:00
There it is - the lunar shadow - very obvious in the animation
Series with half_hourly intervals between May 20, 21:30 UT and May 21, 01:30 UT saved here
Update 20:42 UT
Google Earth screen shots with clouds, weather, travelcams on this gallery
At the end of the eclipse track the southern region around Midland, TX appears to be in fair weather, opposed to the northern part near Amarillo.
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| 20:12 UTC |
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MODIS May 20 16:50-18:35UT, Google Earth May 21 23:19
----------
15:00 UT
Google Earth views of the track of the annular solar eclipse and MODIS satellite images.
May 19, 2012, 17:45-19:30, Bands 7-2-1
More to come.
View also
Near Real Time (Orbit Swath) Images
http://lance-modis.eosdis.nasa.gov/cgi-bin/imagery/realtime.cgi
May 2, 2012
Planning for Solar Eclipses at Sunrise/Sunset
Total or annular solar eclipses occuring at sunrise or sunset provide some extraordinary observing opportunities.Except for the often hard to predict weather, two other critical factors can be treated more accurately - the horizon profile and atmospheric refraction.
Computations for the horizon profile can be done readily with free software, e.g. Microdem or 3DEM and digital elevation models (DEMs). See the overview by Ferranti and Wikipedia.
Microdem impresses by its strong analytical capabilities. Google Earth can produce profiles, but the curvature of the earth is treated somewhat obscurely or not at all.
Refraction cannot be computed with the same kind of precision, a formula can be found in an Intelsat document (PDF) as pointed out to me by Xavier Jubier some months ago.
Earlier horizon hugging eclipses occured 2010 in El Calafate and 2003 in Antarctica.
Now a case study for the annular eclipse of May 20, 2012 for a site just east off the mapped path end at sunset near Garden City, TX. N31d 50.4333m W101d 21.7m
Xavier's tool V1.06 for Google Earth produces results as shown in the screenshot below. Refraction values are displayed by placing the cursor in the elevation fields.
According to Microdem the horizon at Azimuth 294 is at an elevation of 0.4 deg for the selected site. The "ridge" is only about 6 km away. A location closer to Garden City would have a lower horizon.
The Photopgrapher's Ephemeris (TPE) is a nifty tool for planning photos of the setting or rising of the Moon or Sun. Available as free desktop program or apps for Apple and Android.
Computations for the horizon profile can be done readily with free software, e.g. Microdem or 3DEM and digital elevation models (DEMs). See the overview by Ferranti and Wikipedia.
Microdem impresses by its strong analytical capabilities. Google Earth can produce profiles, but the curvature of the earth is treated somewhat obscurely or not at all.
Refraction cannot be computed with the same kind of precision, a formula can be found in an Intelsat document (PDF) as pointed out to me by Xavier Jubier some months ago.
Earlier horizon hugging eclipses occured 2010 in El Calafate and 2003 in Antarctica.
Now a case study for the annular eclipse of May 20, 2012 for a site just east off the mapped path end at sunset near Garden City, TX. N31d 50.4333m W101d 21.7m
Xavier's tool V1.06 for Google Earth produces results as shown in the screenshot below. Refraction values are displayed by placing the cursor in the elevation fields.
According to Microdem the horizon at Azimuth 294 is at an elevation of 0.4 deg for the selected site. The "ridge" is only about 6 km away. A location closer to Garden City would have a lower horizon.
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| Google Earth with Elevation profile along AZ=294 deg |
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| Microdem LOS towards sunset at AZ=294 deg |
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| Microdem Perspective view for site near Garden City, TX |
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| Jubier's calculator for site near Garden City, TX |
The Photopgrapher's Ephemeris (TPE) is a nifty tool for planning photos of the setting or rising of the Moon or Sun. Available as free desktop program or apps for Apple and Android.
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| partial solar eclipse 2011 Jan 04 |
Apr 28, 2012
Shuttle prototype Enterprise
Shuttle prototype Enterprise atop B747 at the Aerosalon in Le Bourget in June 1983
See gallery for more scanned slides
See gallery for more scanned slides
Apr 7, 2012
Besselsche Elemente
Everything you may want to know about Besselian Elements but were afraid to ask is answered in this prize-winning Wikipedia article in German (abridged English version or Google translation).
"Besselsche Elemente" und "Dagobert Duck" - das sind die Themen der beiden Wikipedia-Artikel, die [2010] als besonders hervorragend ausgezeichnet worden sind (Wikimedia Blog, Heise, PediaPress Books for the Zedler Medal)
Background by the author Jürgen Erbs
Die Besselschen Elemente: Ein Mauerblümchen im Rampenlicht
Main sources used are
_ Explanatory Supplement to the Astronomical Almanac, ed. Seidelmann 2006,
contents identical to the 1992 edition and
_ Spherical astronomy, Robin M. Green 1985
On Apr. 02, 2012 John Tilley noted on the Yahoo eclipse mailing list SEML Message #14663:
"The 1992 Explanatory Supplement is NOT recommended, there are several mistakes in the formulae and no worked examples"
Here is a computational example for the total solar eclipse on 1961 Feb 15
from the "Explanatory Supplement to the Astronomical. Ephemeris and the American Ephemeris and Nautical Almanac" 1961, 4th impression 1977
scans pp. 211-224
In Astronomie mit dem Personal Computer
Astronomy on the Personal Computer
by Oliver Montenbruck, Thomas Pfleger,
Springer 4. Aufl., 2004, XIII, 302 S. 46 Abb. Mit CD-ROM.
a method is presented of computing eclipses and local circumstances dispensing with Besselian Elements.
"Besselsche Elemente" und "Dagobert Duck" - das sind die Themen der beiden Wikipedia-Artikel, die [2010] als besonders hervorragend ausgezeichnet worden sind (Wikimedia Blog, Heise, PediaPress Books for the Zedler Medal)
Background by the author Jürgen Erbs
Die Besselschen Elemente: Ein Mauerblümchen im Rampenlicht
Main sources used are
_ Explanatory Supplement to the Astronomical Almanac, ed. Seidelmann 2006,
contents identical to the 1992 edition and
_ Spherical astronomy, Robin M. Green 1985
On Apr. 02, 2012 John Tilley noted on the Yahoo eclipse mailing list SEML Message #14663:
"The 1992 Explanatory Supplement is NOT recommended, there are several mistakes in the formulae and no worked examples"
Here is a computational example for the total solar eclipse on 1961 Feb 15
from the "Explanatory Supplement to the Astronomical. Ephemeris and the American Ephemeris and Nautical Almanac" 1961, 4th impression 1977
In Astronomie mit dem Personal Computer
Astronomy on the Personal Computer
by Oliver Montenbruck, Thomas Pfleger,
Springer 4. Aufl., 2004, XIII, 302 S. 46 Abb. Mit CD-ROM.
a method is presented of computing eclipses and local circumstances dispensing with Besselian Elements.
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