COBS News archive

New Comet C/2018 Y1 (Iwamoto)
December 21, 2018
CBET 4588 & MPEC 2018-Y52, issued on 2018, Dec. 20, announce the discovery of a comet (magnitude ~12) by M. Iwamoto (MPC code 872) in images taken on 2018 Dec 18.8. The new comet has been designated C/2018 Y1 (Iwamoto).

Hubble Takes a Close Look at the Brightest Comet of the Year
December 21, 2018
On December 13th, NASA’s Hubble Space Telescope photographed comet 46P/Wirtanen, a periodic comet that orbits the Sun once every 5.4 years.

Rosetta witnesses birth of baby bow shock around Comet
December 21, 2018
A new study reveals that, contrary to first impressions, Rosetta did detect signs of an infant bow shock at the comet it explored for two years – the first ever seen forming anywhere in the Solar System.

December Comet brings back Rosetta memories
December 15, 2018
A special visitor is crossing the sky: Comet 46P/Wirtanen, sighted with telescopes and binoculars in recent weeks, is on the way to its closest approach to Earth this weekend, when it might become visible to the naked eye.

See a Passing Comet This Sunday
December 15, 2018
On Sunday, Dec. 16, the comet known as 46P/Wirtanen will make one of the 10 closest comet flybys of Earth in 70 years, and you may even be able to see it without a telescope.

A hyperactive comet is approaching Earth
November 29, 2018
Small but hyperactive Comet 46P/Wirtanen is approaching Earth and could soon become visible to the naked eye. On Dec. 16th, the kilometer-wide ball of dirty ice will be less than 11.5 million km away--making it one of the 10 closest-approaching comets of the Space Age. It already looks magnificent through amateur telescopes.

NASA learns more about interstellar visitor 'Oumuamua
November 16, 2018
The first known interstellar object to visit our solar system -- named 'Oumuamua -- was detected in October 2017 by Hawaii's Pan-STARRS 1 telescope. But it was too faint for NASA's Spitzer Space Telescope to detect when it looked more than two months after the object's closest approach to Earth in early September. That 'non-detection' puts a new limit on how large the strange object can be, astronomers now report.

New Comet C/2018 V1 (Machholz-Fujikawa-Iwamoto)
November 12, 2018
CBET 4569 (issued on 2018, November 08) and MPEC 2018-V151 (2018, November 11), announce the discovery of a 10th-magnitude comet by Donald E. Machholz (Colfax, CA, U.S.A) and independently by Shigehisa Fujikawa (Kan'onji, Kagawa, Japan) and Masayuki Iwamoto (Awa, Tokushima, Japan).

Comet tails blowing in the solar wind
November 04, 2018
Combined observations of Comet McNaught -- one of the brightest comets visible from Earth in the past 50 years -- have revealed new insights on the nature of comets and their relationship with the Sun.

Secret shared by comets and sand crabs
October 26, 2018
Researchers have found a mechanical connection between sand crab burrow widths and widths of cometary pits using a simple granular experiment.

Comet landscape
October 03, 2018
On 30 September 2016, ESA’s Rosetta spacecraft came closer than ever to the target it had studied from afar for more than two years, concluding its mission with a controlled impact onto the surface of Comet 67P/Churyumov-Gerasimenko (67P/C-G).

Gaia finds candidates for interstellar ‘Oumuamua’s home
September 26, 2018
Using data from ESA’s Gaia stellar surveyor, astronomers have identified four stars that are possible places of origin of ‘Oumuamua, an interstellar object spotted during a brief visit to our Solar System in 2017.

Observation Alert: Extremely bright mag 12.2 outburst of Comet 29P
September 24, 2018
A second outburst of 29P/Schwassmann-Wachmann has taken place on 2018 09 23.2 +/-0.1 which has raised its brightness from r mag 13.2 to 12.2. This new outburst occurred 2.6 +/-0.2 days after this first event and its current brightness makes it one of the four most intense outbursts in 8 years.

The Comet Observation Database - Structure and content (EPSC 2018-632, Berlin 2018)
September 10, 2018

The Comet Observation Database (COBS) [1, 2] is a unique web service that enables comet observers to submit, display and analyse comet data in a single location. The service currently represents one of the largest databases of comet observations (containing more than 235,000 observations) and is available to comet observers worldwide.

The Comet Observation Database - Observer tools and case study (EPSC2018-644, Berlin 2018)
September 10, 2018

This paper introduces the main functionality of the COBS database [1, 2] that is of interest to a comet observer, with application to C/2004 R2 (Machholz).

Green comet makes closest approach to earth
September 09, 2018
On Sept. 10th, Comet 21P/Giacobini-Zinner ("21P" for short) will make its closest approach to Earth in 72 years--only 58 million km from our planet. This small but active comet is easy to see in small telescopes and binoculars as it shines like a 7th magnitude star. Michael Jäger of Weißenkirchen, Austria, sends this photo of 21P passing through the stars of Auriga on Sept. 7th.

A Green Comet Approaches Earth
August 25, 2018
Comet 21P/Giacobini-Zinner is approaching Earth. On Sept. 10th, it will be 0.39 AU (58 million km) from our planet and almost bright enough to see with the naked eye. Already it is an easy target for backyard telescopes.

The cautionary tail of Comet Swift–Tuttle
August 10, 2018
Comet Swift–Tuttle, formally 109P/Swift–Tuttle, is an enormous, icy comet on a 133 year orbit around the Sun, and the reason for the spectacular annual Perseids meteor showers on Earth.

New Comet: C/2018 N2 (ASASSN)
July 18, 2018
MPEC 2018-O01, issued on 2018, July 16, announces the discovery of a comet (magnitude ~16.1) in the course of the "All-Sky Automated Survey for Supernovae" (ASASSN) program, in images taken 2018 July 7-11 with the 14-cm "Cassius" survey telescope at Cerro Tololo. The new comet has been designated C/2018 N2 (ASASSN).

Molecular oxygen in comet's atmosphere not created on its surface
July 09, 2018
Scientists have found that molecular oxygen around comet 67P is not produced on its surface, as some suggested, but may be from its body.