Gemini North with a swirl of star paths about the SCP

    Caption: Gemini North is an 8-meter class telescope on Mauna Kea, Hawaii.

    Mauna Kea rises to 4,145 m (13,600 ft) and is one of the world's best observing sites---located fortunately in one of the world's best tourist sites---but the air is thin up on the mountain.

    In the image, we see a swirl of stars in a long-exposure image.

    The star trails are ∼ 20° (1/18 of 360°), and so the exposure time was ∼ 1/18 days = 4/3 h ≅ 1.33 h. To get the angle, shape a 90° angle with your hands and estimate from that.

      Question: Mauna Kea is at 19°40' north latitude. In the Northern Hemisphere, the NCP is above the horizon and the SCP is below the horizon.

      So the image is looking:

      1. east.
      2. west.
      3. south.
      4. north.











      Answer 3 is probably right.

    The center of the star trails seems to be below the level-ground horizon. Just imagine radii extending perpendicularly from the ends of the star trails. They seem to converge well below the horizon to yours truly. So yours truly thinks we are probably looking south and the stars are swirling about the SCP.

    Note there is a meteor trail just about perpendicular to the star trails. The trail is too short to be the trail of an artificial satellite. Also note that the red-yellow streaks are the tail lights of cars driving up the mountain during the exposure time. The light from meteor and cars were sampled everywhere along their paths despite being on a much shorter time scale than the motion of the stars.

    Looking at this image it is possible to see why some of ancient Greek philosophers (most notably Democritus (c.460--c.370 BCE) and the other atomist philosophers) theorized that the cosmos was a giant vortex (see, e.g., Fu-140ff).

    Credit/Permission: © Gemini Observatory, NOAO, AURA, NSF, before or circa 2005 / NOAO/AURA Image Library Conditions of Use.
    Download site: NOAO: Gemini North at night.
    Image link: Itself.
    Local file: local link: gemini_north_swirl.html.
    File: Telescope file: gemini_north_swirl.html.