THE DAILY ASTRONOMER
Tuesday, November 5, 2019
November 2019 Night Sky Calendar Part II
WEDNESDAY, NOVEMBER 13, 2019: MOON NEAR THE PLEIADES
The waning gibbous moon (99%) illuminated will appear to pass close to the Pleiades Star Cluster tonight. Now that we've entered late autumn, the Pleiades will be visible all night long. This cluster is considered the first of the winter star patterns, heralding the arrival of the cold season. As the moon appears nearly full, its light will obscure, but not entirely wash out, this cluster.
The Pleiades Star Cluster located in Taurus the Bull.Even though this cluster is known as the "Seven Sisters,"
the Pleiades consists of hundreds of stars bound together
gravitationally. This time exposure photograph reveals the
"Maia Nebula," a gaseous cloud illuminated by the cluster's stars.
SUNDAY, NOVEMBER 17/MONDAY NOVEMBER 18, 2019: LEONID METEOR SHOWER PEAKS (Gold event!!!)
Why list two dates? Simple: the Leonid meteor shower peaks on the night of November 17-18th. As the best time to watch a meteor shower is between midnight and the pre-dawn, the best viewing will occur on November 18th.
The Leonid meteor shower occurs between November 6 - 30th. During this period, Earth moves through a stream of particles released by Comet Tempel-Tuttle. When this comet moves through the inner solar system. the Sun's heat causes the comet's surface ice to sublimate: transition from solid to vapor without passing through the intervening liquid phase. Dust released from the dissipating ice remains along the comet's path. When Earth travels through this stream, many of the meteoroids descend through the atmosphere. During their descent, the meteoroids excite surrounding atoms, causing their electrons to ascend to higher energy orbits. When these electrons return to their original states, they emit the photons we perceive as the meteors.
The Leonid Meteor Shower. Fragments of the Comet Tempel-Tuttle
infiltrate our atmosphere between November 6 - 30. These descending
meteoroids excite nearby atmospheric atoms by elevating their electrons
to higher energy states. These electrons emit photons when they
revert to their original states. We perceive these photons as the meteors.
Meteor showers are generally named for the constellation from which
the meteors appear to emanate, hence the name "Leonid."
Image: EarthSky.org
The Leonid Meteor shower is notorious for producing meteor storms every 33 years approximately. As its parent comet's swoops through the inner solar system once every 33 years to replenish the meteoroid swarm along the comet's path.
On the night of November 17/18, one should expect to see 10 - 15 meteors an hour. The waning gibbous moon (74% illuminated) will interfere with viewing, reducing the number of meteors that observers would otherwise have seen.
TUESDAY, NOVEMBER 19: LAST QUARTER MOON
SUNDAY, NOVEMBER 24: VENUS 1.4 DEGREES SOUTH OF JUPITER (SILVER EVENT!!)
We will see the two brightest planets apparently close together in the western evening sky tonight. Distinguishing between them shouldn't prove difficult, as Venus will be almost seven times brighter than
Jupiter. Both planets will set by 5:45 p.m.
TUESDAY, NOVEMBER 26: NEW MOON
Beginning of lunation cycle 1199
THURSDAY, NOVEMBER 28: MERCURY AT GREATEST WESTERN ELONGATION (20 degrees)
Mercury is a rapid mover! Earlier this month, the elusive little world moved directly across the Sun from our vantagepoint. Now, on Thanksgiving, it will attain its greatest western elongation. Find it in the pre-dawn eastern sky.
THURSDAY, NOVEMBER 28: MOON NEAR VENUS
Why do we post a specific angular distance when speaking of two planets, but are more vague when referring to the moon and a planet? Simply because the moon moves more quickly than the planets: by about 1/2 a degree an hour. For this reason, it doesn't make sense to post an angular separation value, as it would be valid for only a brief part of the night. See the waxing crescent moon (5% illuminated) close to Venus low in the western evening sky.
FRIDAY, NOVEMBER 29: MOON NEAR SATURN
In case you missed the previous entry: Why do we post a specific angular distance when speaking of two planets, but are more vague when referring to the moon and a planet? Simply because the moon moves more quickly than the planets: by about 1/2 a degree an hour. For this reason, it doesn't make sense to post an angular separation value, as it would be valid for only a brief part of the night. See the waxing crescent moon (11% illuminated)