– the comet that is now like a faint star close to brilliant Arcturus. Continue reading “More on Catalina”
Month: December 2015
Comets Catalina and Berenices
Comet Catalina (C/2013 US10) is now fairly easily findable in binoculars as it climbs from eastern Virgo into Boötes, and when several people remarked on this I remembered about Berenice’s Comet.
The Sea as a Bell
We traveled by train to Portugal, taking four days, but hastened home at thirty thousand feet.
The remains of December
The Geminids come around again
Here is a space-picture of how the meteors of this stream cross Earth’s orbit.
Sky scene, December 12
Put a telescope in your local library
This guest article is by John Jardine Goss, President of the Astronomical League. His subtitle for it is: “The perfect club project.”
Cascade
Tomorrow morning, you can see the Moon about to eat Mars.
But, the morning after, Mars will still be there, as the Moon continues on its way down the row of planets in the morning sky.
It passes Mars very closely, then Venus less closely, then Saturn rather widely. The separations (between the Moon’s center, as seen from the Earth’s center) and the planets are 0.13, 1.1, and 3.1 degrees.
The Mars encounter happens at Dec. 6, 3 hours Universal Time, thus for Europe and America in deep night between Dec. 5 and 6. So on the morning of Dec. 5 we see the Moon before it reaches Mars, and on the next morning, after. The Mars conjunction is so close that the Moon occults (covers) the planet as seen across a central band of the Earth. Because of the timing in Earth’s rotation, the only region favorably placed to see the occultation in a dark sky is eastern Africa. Skilled Australian observers may, in their afternoon sky, be able to pick up the bright pinpoint of Mars just before it hits the scimitar-like curve of the Moon’s advancing edge.
Detail from the “Occultations” section of Astronomical Calendar 2015.
Venus, too, will be occulted, on Dec. 7 at 17 UT, which means the occultation track passes over North America, but in daylight.
By the time the Moon reaches Saturn, on Dec. 10 at 15 UT, they are impractically low to the sunrise horixon, only about 10 degrees from the Sun, the Moon extremely thin because it will be at its New position the next day. 11.
Comet C/2013 US10 Catalina, now appearing near to Venus, is, we hope, in its climb toward perceptibility with the naked eye. It is also climbing northward, to pass near Arcturus on January 1.
Crossings
As Mars passed Jupiter early today, a gong sounded, or so I whimsically imagined. But how often does that happen?
