ALPO COMET SECTION NEWS FOR JANUARY 2015
2015-January-4
Latest News
Happy New Year!
2014 was a banner year for the ALPO Comet Section. The Section’s online image gallery increased from 268 images of 56 different comets to 883 images of 133 comets. An important fraction of this increase consisted of older archival images and drawings being placed online for the first time. Observers contributed 306 visual and CCD magnitude measurements for 17 comets. The best observed comets of 2014 were C/2014 E2 (Jacques) with 61 images and C/2012 K1 (PANSTARRS) with 76 magnitude measurements.
I have started producing finder charts for some of the brighter comets with the Sky Tools 3 software. The charts can be found at ‘Comet Finder Charts‘ under the list of ‘Pages’ on the Comet Section homepage.
Evening Comets
C/2014 Q2 (Lovejoy) [Perihelion on 2015-Jan-30 at 1.29 AU from the Sun]
The brightest comet of 2014 may very well be the brightest comet of 2015 as well. As the year begins, Comet Lovejoy is around magnitude 4.5 and a nicely placed evening object for most observers. Many observers have reported seeing the comet as a faint naked eye object with a coma diameter of 20′. Telescopically, a faint, long northward pointing ion tail may be visible. Though the tail has not been very prominent visually, it has been imaged at many degrees long. Lovejoy starts January at 1.36 AU from the Sun and ends the month at perihelion (1.29 AU). Its distance from Earth starts at 0.50 AU, decreases to a close approach minimum of 0.47 AU on the 7/8th, and increases to 0.77 AU by the end of the month. Peak brightness should occur this month around magnitude 4.2 or so. Though it will fade after close approach to Earth it should still be around 5th magnitude on Jan 31. The comet rockets to the northwest through the following constellations this month: Lepus (Jan 1-2), Eridanus (2-9), Taurus (9-16), Aries (16-24), Triangulum (24-30) and Andromeda (30-31).
The plot below shows a lightcurve of C/2014 Q2 produced from visual and CCD magnitude measurements submitted to the Section. The image sequence by Gianluca Masi of Italy highlights changes in the tail of the comet during the last weeks of 2014.
Recent ALPO images and observations of C/2014 Q2 (Lovejoy) can be found in the Comet Section Image Gallery and Magnitude Database. Finder charts can be found at the ALPO Comet Finder Chart page.
15P/Finlay [Perihelion on 2014-Dec-27 at 0.98 AU from the Sun]
William Henry Finlay discovered this short-period comet with a 18-cm refractor from the Royal Observatory in South Africa in 1886. Completing an orbit roughly every 6.5 to 7 years, this marks its 15th observed apparition having been missed at 5 since discovery. Comet Finlay was expected to reach magnitude 10-11 this December/January. Surprisingly, it has undergone an outburst and was observed at 9th magnitude in late December. The comet is now back below 10th magnitude but should be watched for additional outbursts. Its distance increases from 0.98 to 1.11 AU from the Sun and reaches a minimum from the Earth of 1.39 AU mid-month. Finlay is also an evening object moving though Capricornus (Jan 1-4), Aquarius (4-20) and Pisces (20-31).
Recent ALPO images and observations of C/2014 Q2 (Lovejoy) can be found in the Comet Section Image Gallery and Magnitude Database. Finder charts can be found at the ALPO Comet Finder Chart page.
New Discoveries
Three new comets were discovered since the last monthly Section News. Russian astronomer Leonid Elenin discovered his third comet, P/2014 X1 (Elenin), with a telescope in New Mexico. New Comet Elenin is on a 15-year orbit with a perihelion of 1.8 AU. It will get no brighter than 16th magnitude. C/2014 XB8 (PANSTARRS) [perihelion on 2015-Apr-05 at 3.0 AU) will remain fainter than 20th magnitude. C/2014 Y1 (PANSTARRS) may get as bright as 13th magnitude around its January 2016 perihelion at 2.2 AU. It is currently 18th magnitude.
As always, the Comet Section is happy to receive all comet observations, whether images, drawings or magnitude estimates.
- Carl Hergenrother (ALPO Comet Section Coordinator)
