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lunar eclipse 2017-02-11
Penumbral lunar eclipse 2017-02-11.

Astro images

A lunar eclipse occurs when the Full Moon moves through the shadow of the Earth. On this occasion, the Moon misses the core shadow were no direct sunlight enters (the umbra) and dips only into the penumbra, where part of the Sun is still shining on the Moon. The red circles mark the boundaries of the (inner) umbra and (outer) penumbra.

This image is taken at 00:29:25 UT, about 15 min before deepest eclipse. The penumbral phase (the fraction of the lunar diameter within the shade) is 0.997. These 5 min are the only gap in the clouds between first contact and greatest eclipse.

The optics is a Telementor II 60/840 mm (aperture/focal length) refractor, with focal ratio f/13.3, set up in Edinburgh. The camera is a Canon EOS 600D (with Hα enhancement and CLS light pollution filter, which are not relevant here), used at 100 ISO with 8 ms exposure time. A single frame is used, with two dark frames. The raw linear green channel is converted with γ = 2.2 to grey JPG.

Recent changes

  • The 2017 NLC season has ended.
  • The daily calculation of ephemerides is discontinued.
  • The (few) non-astronomical pages are removed.

Site map

  • Noctilucent cloud: During the 2009 to 2017 seasons, observations of NLC were added continuously.
  • Astrophotography: An introduction into using a digital single lens reflex (dSLR) camera or a webcam to take pictures of astronomical objects.
  • Astro images: More pictures I have taken of astronomical objects.
  • Algol project: Materials and tips for observing this most famous variable star.
  • Software: I have written a few applications to do with ephemerides and with astro imaging. These are available for your use and improvement under the GNU General Public Licence.
  • Stockert is a now historic radio telescope in the Eifel hills near Bonn, Germany.
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