This is a great post! Enjoy!
Photo Caption: Moon and Venus entering Clouds, by David Levy
Skyward for September 2020.
How to see more than half the solar system at once
David H. Levy
Have you ever wondered if you
could see more than half the solar system at once? An opportunity to do so does not come about
often, but it does happen from time to
time. A couple of summers ago, Venus,
Mars, Jupiter, and Saturn were all in the evening sky and could be spotted at
once. Now, during this summer of 2020 a
couple of hours before dawn, Mars, Jupiter, and Saturn are all in the sky and
can be seen at the same time.
The procession begins in the
evening, with Jupiter and Saturn easily visible at about the same time in the
east. Jupiter is brighter than all the
stars on a summer night, and through a telescope, the rings of Saturn are
exquisite. Jupiter and Saturn appear to get close in the sky every twelve
years, or about once every Jupiter orbit of the Sun. They were close together in 1960, 1972, 1984,
1996, 2008, and now. They were not far apart when I first looked at Jupiter
through a telescope on September 1, 1960.
Galileo himself could have felt no greater thrill than I did when I used
my first telescope, Echo, and saw the wonderful planet, surrounded by four
bright moons and decorated with gas bands in its upper atmosphere. Dad and Mom were with me and they enjoyed
that unforgettable view as well. You
too can replicate that experience on the next clear night.
Toward the east, Mars is brightening with
every night as it gets closer to Earth.
Through a good telescope you should be able to see a polar cap, and dark
markings on its surface like the prominent Syrtis Major or the very large Mare
Acidalium. Mars has two tiny moons,
Phobos, and Deimos. I have seen Phobos,
one night many years ago, using a large 36-inch diameter reflector. Two spacecraft are now on their way to
Mars. One carries a rover and a
helicopter intended to search for evidence of past life on this planet.
Towards dawn, Venus rises in
the northeast. Although it is the
brightest planet (and the brightest object in the sky after the Sun and the
Moon), Venus offers virtually nothing to see through its dense clouds, even
using a good telescope. However, on rare
occasions it gets occulted by the Moon.
The attached picture is of one such event I saw.
During about half of the
nights this summer, the Moon joins this pantheon of planets. Because the Moon is a real place that we
have visited, not just an object in the sky, it is a real treat in any
telescope. Walk across the craters,
climb its mountains, and skate along its enormous maria, or plains. The Moon is always wonderful.
It is not a trick to see so
much of the solar system at once. Late
on the night of August 12, 2020, while observing the Perseid meteors, I viewed
Jupiter low in the west, and Saturn just a bit higher in the sky. Mars was high in the south. Further east shone the waning crescent
Moon. Finally, Venus was low in the
east.
You do not need a telescope to see all
this. Just open your eyes and behold the
wonder of our tiny neighborhood in the cosmos.
