Explanation:
Remember when the Moon was young?
It was just last Monday.
On May 9th, this slender crescent Moon
was recorded at
a tender age of 34 hours and 18 minutes.
Well, OK ... when calculating the
lunar age during a
lunation or complete
cycle
of phases - from New Moon to Full Moon and
back to New Moon again - the Moon never
gets more thanaround
29.5 days old.
Still, a young Moon can be a
rewarding sight, even for
casual skygazers, though the slim crescent is relatively
faint and only easy to see
low in
the west as the sky
grows dark after sunset.
Sighting this young Moon last
Monday, lucky astronomer Stefan Seip was also treated to a very
dramatic telescopic view of an airliner flying
in front of the distant sunlit crescent.
At a high altitude, the jet's stunning contrails reflect
the strongly reddened light of the Sun setting below the
western horizon.