Explanation:
Orbiting 400,000 kilometers above the Earth, the
Moon slid
into Earth's shadow to begin last week's total lunar
eclipse.
Of course the
International Space Station (ISS) slides into
Earth's shadow every 90 minutes, the time it takes it to complete one
orbit at
an altitude of about 400 kilometers.
Recorded near sunset on February 7,
looking toward the north,
this
composite of 70 exposures shows the trail of the
ISS (with gaps between exposures) as it moved left to right
over the city of Tübingen in southern Germany.
Beginning
in sunlight on the left, the ISS vanishes as it enters
Earth's shadow at the far right, above the northeastern horizon.
As seen from Tübingen, the passage took about 4 minutes.
Clicking on the image will download a
time-lapse animation
(mpg file) based on the individual exposures that includes a plane flying
along
the horizon.
digg_url = 'http://apod.nasa.gov/apod/ap080228.html'; digg_skin = 'compact';
