Twilight Evening Planets — Venus, Jupiter and Saturn
As the sky darkens tonight, look to the southwest to spot two bright planets. Dazzling Venus, above left, and bright Jupiter, below and right.
Jupiter is sinking toward the setting sun each night, while Venus continues a slow climb. By Dec. 10, say farewell to the largest gas giant, Jupiter, as it is lost in the setting sun’s glare.
As Jupiter slips, Venus soars toward the other gas giant, Saturn. On Dec. 10 and 11, Venus will be less than 2 degrees from the ringed world. After this brief sojourn, Venus races away from sinking Saturn.
We can say farewell to the last gas giant, Saturn by the first night of winter, Dec. 21.
Evening Planets — Neptune and Uranus
Telescope observers will find the two ice giants, Neptune and Uranus, well placed for observing all month. Start searching for Neptune in Aquarius just after 6 p.m. tonight. About three hours later, slightly brighter Uranus can be found in Pisces.
Each night this month, Neptune and Uranus rise a bit earlier and reach excellent observing altitudes. By mid-month, Neptune will be well placed as the sky darkens, while Uranus follows just before 8 p.m. As 2019 closes, Neptune will continue to be ready for observing just after dark, while Uranus is well placed by 7 p.m.
Dawn planets — Mars and Mercury
Dawn skies will reveal two planets in December, Mercury and Mars.
Best views of Mercury will be tomorrow morning, as the speedy planets retreats toward the rising sun each morning. Look about an hour before sunrise toward the east-southeast to spot moderately bright Mercury. Up and to the right is dim Mars.
Mercury disappears in the dawn sky by mid-month, while Mars climbs a bit higher each morning. Distant Mars gains a tiny bit of brightness but its small apparent diameter makes telescope observing less than useful.
Geminids and Ursid Meteor Showers
December brings two meteor showers to Oregon skies. The major shower is the Geminids that peak on the morning of Dec. 14. Unfortunately, a bright moon in Gemini will interfere with this shower.
Meteor observers can pursue two strategies. One, look just after dark to the southeast or northeast along the horizon to spot early bright Geminids before the moon rises. Two, after 10 p.m., if skies are clear, brave the cold and look to the west-southwest to northwest with the moon at your back — better if you can block the moon with a building or tall tree.
Geminids are generally bright so that as many as 20 per hour may be seen in moonlight. Good luck and good observing.
The second minor meteor shower is the Ursids that peak on the night of Dec. 21. Look to the northeast or northwest to spot dim meteors racing from the bowl of the Little Dipper. Only about 10 to 15 meteors per hour will be visible at the peak. Begin watching after dark for early Ursids and then after midnight for higher counts.
Morgan Observatory at U.C.C. (PMO) No Scheduled Events
Please check www.umpqua.edu/observatory for short notice events. Typical December weather will limit observing during the remainder of the winter months.
Umpqua Astronomers Meeting- Next Public meeting January 2020
Come at 7 p.m. on Jan. 14, 2020, to Wayne Crooch Hall Room 10 for the Umpqua Astronomers monthly meeting. Anyone wanting a Q & A session about astronomy, telescopes or general star gazing information please come at 6:30 p.m.
Club news, monthly sky events and astronomy news will be presented at the monthly meeting. Astronomy events for 2020 will be discussed. Everyone interested in astronomy is welcome.
After the meeting, if skies are clear, join local astronomers for an observing session at the Morgan Observatory after the meeting.