Comets & Asteroids - Summary for November 2016

During the month of November 2016, 1 new comet has been discovered. "Current comet magnitudes" & "Daily updated asteroid flybys" pages are available at the top of this blog (or just click on the underline text here).  

The dates below refer to the date of issuance of CBET (Central Bureau Electronic  Telegram)  which reported the official news & designations.

- Comet Discoveries

Nov 03  Discovery of C/2016 U1 (NEOWISE)

- Other news

Nov 02 Newly discovered asteroid 2016 VA came to about 90.000 km from the Earth’s surface on the second day of November, reaching magnitude  12. It crossed the Earth shadow for a few minutes (between 23:24-23:35 UT on Nov 01, just 0.3 LD from Earth), challenging  astronomers to observe a peculiar “asteroidal eclipse”. Below you can see an animation showing this spectacular event as observed by G. Masi (Virtual Telescope Project). According to Masi: "Each frame comes from a 5-seconds integration. At the eclipse time, the asteroid was moving with an apparent motion of 1500"/minutes"

Nov 07 Roy Panther (1926 - 2016), British visual comet discoverer passed away. Obituary by N. James: "Roy was the discoverer of comet C/1980 Y2 (1980u). The discovery was made visually using a 0.20m, f/4 Newtonian at 1850 UT on Christmas day 1980 when the comet was a 9th magnitude object near M56. The discovery was confirmed that evening by Mike Hendrie and George Alcock and it was Roy's first success after 601 hours of searching.  Martin Mobberley has an interesting Sky at Night on his Youtube channel which includes an interview with Roy."

Roy Panther with his 8-inch 'old discoverer'

Nov 07 K. Battams & M. Knight published on Arxiv a summary paper of the more than 3,000 sungrazing and near-Sun comets discovered in coronagraph images returned by the Solar and Heliospheric Observatory (SOHO), since its launch in December 1995.

Credit: K. Battams & M. Knight

Nov 10 CBET 4336 reports that minor planet (5112) KUSAJI  is a binary system with an orbital period of 20.74 +/- 0.01 hr.  The primary shows a period of 2.7995 +/- 0.0001 hr and has a lightcurve amplitude of 0.12 mag at solar phases 4-8 degrees, suggesting a nearly spheroidal shape.

by Ernesto Guido

Comets & Asteroids - Summary for October 2016

During the months of October 2016, 3 new comets were discovered. "Current comet magnitudes" & "Daily updated asteroid flybys" pages are available at the top of this blog (or just click on the underline text here).  

The dates below refer to the date of issuance of CBET (Central Bureau Electronic  Telegram)  which reported the official news & designations.

- Comet Discoveries

Oct 11  Discovery of C/2016 T1 (MATHENY)

Oct 13  Discovery of C/2016 T2 (MATHENY)

Oct 18  Discovery of C/2016 T3 (PANSTARRS)

- Other news

Oct 14 Klim Ivanovich Churyumov (1937 - 2016), astronomer and co-discoverer (with Svetlana Gerasimenko) of comet #67P passed away on October 14, 2016 

Oct 17 The third-largest object known beyond Neptune, 2007 OR10, has a moon. The discovery was reported in a poster by Gábor Marton, Csaba Kiss, and Thomas Mueller presented at the joint meeting of the European Planetary Science Congress and the Division for Planetary Sciences of the American Astronomical Society (DPS/EPSC) in Pasadena, California. The Hubble Space Telescope took the photo below of 2007 OR10 on September 18, 2010. Later analysis of the images revealed the presence of a moon (red circle).

Credit: NASA / STScI / Wesley Fraser / Gábor Marton et al.

Oct 26 Lutz D. Schmadel (1942 - 2016), author of the Dictionary of Minor Planet Names, died on Friday October 21, 2016

Oct 27 Catalog of Known Near-Earth Asteroids Tops 15,000, with an average of 30 new discoveries added each week. This milestone marks a 50 percent increase in the number of known NEAs since 2013, when discoveries reached 10,000 in August of that year. The 15,000th near-Earth asteroid is designated 2016 TB57. It was discovered on Oct. 13 by observers at the Mount Lemmon Survey.

Oct 29 #TeamRadar at Arecibo imaged binary asteroid 2003 YT1 on the morning of Oct 29, 2016. Asteroid 2003 YT1 was discovered by the Catalina Sky Survey in December 2003. This asteroid approached within 0.035 au (13.5 lunar distances) on October 31. Radar observations at Arecibo in May 2004 revealed that this is a binary system with a rapidly-rotating primary and a secondary whose orbital and rotation periods appear to be asynchronous.  The primary has a rotation period of 2.34 h and the upper bound on the rotation period of the  secondary is about 6 h. In the new obtained image below, the faint smudge at the top is the satellite moving in its orbit over 2 hours. 

Credit: @AreciboRadar

by Ernesto Guido

Comets & Asteroids - Summary for August & September 2016

During the months of August & September 2016, 10 new comets were discovered, cometary activity was detected for 4 previously discovered object (earlier designated as an asteroid) and there were 3 comet recoveries. "Current comet magnitudes" & "Daily updated asteroid flybys" pages are available at the top of this blog (or just click on the underline text here). 

The dates below refer to the date of issuance of CBET (Central Bureau Electronic Telegram)  which reported the official news & designations.

- Comet Discoveries

Aug 14  Discovery of P/2016 P1 (PANSTARRS)

Aug 14  Discovery of P/2016 P2 (PANSTARRS)

Aug 29  Discovery of P/2016 N6 (PANSTARRS)

Aug 31  Discovery of C/2016 Q2 (PANSTARRS)

Sep 02   Discovery of C/2016 Q4 (KOWALSKI)

Sep 09   Discovery of C/2016 P4 (PANSTARRS)

Sep 09   Discovery of C/2016 R2 (PANSTARRS)

Sep 16   Discovery of C/2016 R3 (BORISOV)

Sep 29   Discovery of C/2016 S1 (PANSTARRS)

Sep 29   Discovery of P/2016 R4 (GIBBS)

- Cometary activity detected

Aug 10  Cometary activity detected in 2014 HU_195 = C/2014 HU_195

Aug 15  Cometary activity detected in 2015 TP_200  = P/2015 TP_200 (LINEAR)

Aug 31  Cometary activity detected in 2008 SH164   = P/2016 Q3 (LINEAR)

Sep 27   Cometary activity detected in P/2009 Q9       = P/2016 SV (PANSTARRS)

- Comet Recoveries

Aug 15  Recovery of P/2003 SQ_215 (NEAT-LONEOS) as P/2016 P3

Aug 31  Recovery of P/2005 S3 (READ) as P/2016 Q1

Sep 03   Recovery of P/2007 T6 (CATALINA) as P/2016 R1

- Other news

Aug 02 July Gamma Draconid meteor shower showed a little outburst between July 27d 23h56m and July 28d 00h23m UT as showed by IMO and CAMS meteor video camera networks and by Canadian Meteor Orbit Radar data. The observed rate translates to a peak zenith hourly rate for a visual observer (assuming a differential mass distribution index of 1.9) of about 50 meteors per hour for the period 0h-1h UT on July 28.

Credit: IMO

Aug 04 A bright sungrazer heading towards the Sun imaged by the ESA/NASA Solar & Heliospheric Observatory SOHO 03 & 04 August 2016.

Credit: SOHO

Sep 01 Comet 174P/ECHECLUS = (60558) ECHECLUS was found in outburst by P. Camilleri, brightening from magnitude r' = 17.8 to 15.2 between Aug 27.745 and 28.686 UT in a photometric aperture of radius 5".2. 

Sep 05 The search for @Philae2014 is OVER! Less than a month before the end of the mission, Rosetta’s high-resolution camera has revealed the Philae lander wedged into a dark crack on Comet 67P/Churyumov–Gerasimenko. The images were taken on 2 September by the OSIRIS narrow-angle camera as the orbiter came within 2.7 km of the surface and clearly show the main body of the lander, along with two of its three legs.

Credit: ESA/Rosetta

Sep 07 Close approach of asteroid 2016 RB1. Asteroid 2016 RB1 (estimated size of 7.3 m - 16 m) had a close approach with Earth at about 0.1 LD (Lunar Distances = ~384,000 kilometers) on 2016, September 7 at 17:20UT reaching a peak magnitude of about +12.3.

Sep 24 Time-resolved observations of the split comet 332P/Ikeya-Murakami were taken using the Hubble Space Telescope.

Credit: D. Jewitt et al.

Sep 30 ESA’s historic Rosetta mission has concluded as planned, with the controlled impact onto the comet it had been investigating for more than two years. Confirmation of the end of the mission arrived at ESA’s control centre in Darmstadt, Germany at 11:19 GMT (13:19 CEST) with the loss of Rosetta’s signal upon impact.

During the the spacecraft’s controlled descent, OSIRIS narrow-angle camera aboard Rosetta imaged comet 67P/Churyumov-Gerasimenko from an altitude of about 16 kilometers above the surface. Credit: ESA/Rosetta

A last image of comet 67P taken by Rosetta shortly before impact at an altitude of 20m above surface. The scale is 2 mm/pixel and the image measures about 96 cm across. Credit: ESA/Rosetta

by Ernesto Guido

BRIGHT NOVA IN LUPUS - (PNV J15290182-4449409)

Following the posting on ATel #9538 & #9539 and on the Central Bureau's Transient  Object Confirmation Page about a possible bright Nova in Lupus (TOCP Designation:  PNV J15290182-4449409)  discovered in the course of the V-band All-Sky Automated Survey for Supernova (ASAS-SN) on images obtained on Sept. 24.010 UT using the robotic 14-cm telescopes, I performed some follow-up of this object remotely through a 0.32-m f/9 reflector + CCD + f7 focal reducer of iTelescope network (MPC Code  Q62 - Siding spring, Australia).

On my images taken on September 27.4, 2016 I can confirm the presence of an optical counterpart with unfiltered magnitude about 6.5 - 7.0 (rough estimate) at coordinates:

R.A. = 15 29 01.76, Decl.= -44 49 39.7 (equinox 2000.0; UCAC-4 catalogue reference stars).

Below my image of Nova Lupus. Details on the caption. Click on the image for a bigger version.

An animation showing a comparison between my confirmation image and the archive POSS2/UKSTU Red plate (1992-07-30). Click on the thumbnail below for a bigger version:

According to the Cbet 4322 issued on September 27, 2016: "T. Bohlsen (Armidale, NSW, Australia) obtained a noisy spectrogram on Sept. 24 (time unknown) that shows H_alpha emission and also an image that yielded magnitude V = 6.8; he surmised from this that the variable does appear to be a galactic nova."

by Ernesto Guido

Close Approach of Asteroid 2016 RB1

The asteroid 2016 RB1 was discovered  (at ~ magnitude +19) on 2016, September 05 by Mt. Lemmon Survey (MPC code G96) with a 1.5-m reflector + 10K CCD. 

Asteroid 2016 RB1 has an estimated size of 7.3 m - 16 m (based on the object's absolute magnitude H=27.8) and it will have a close approach with Earth at about 0.1 LD (Lunar Distances = ~384,000 kilometers) or 0.0003 AU (1 AU = ~150 million  kilometers) on 2016, September 7 at 17:20UT and it will reach a peak magnitude of about +12.3. Radio astronomers will try to  observe it as 2016 RB1 could be a really strong radar target during its close approach.

I performed some follow-up measurements of this object on 2016, September 07.6, remotely from the Q62 iTelescope network (Siding Spring, Australia) through a 0.4-m f/3.5 reflector + CCD. Below you can see our image taken with the asteroid at about magnitude +13 and moving at ~ 503 "/min. At the moment of its close approach on Sep 07, around 17UT, 2016 RB1 will move at ~ 2716 "/min (or about  45.2 deg/hour). The asteroid is trailed in the image due to its fast speed. Click on the image below to see a bigger version. (North is up, East is to the left). 

by Ernesto Guido

Comets & Asteroids - Summary for July 2016

During the month of July 2016,  1 new comet has been discovered and there were 4 comet recoveries. An international team of astronomers discovered a new dwarf planet (designated 2015 RR245) orbiting  in the disk of small icy worlds beyond Neptune. The Team Radar at Arecibo observed the Near-Earth asteroid (154244) 2002 KL6. "Current comet magnitudes" & "Daily updated asteroid flybys" pages are available at the top of this blog  (or just click on the underline text here).

The dates below refer to the date of issuance of CBET (Central Bureau Electronic Telegram)  which
reported the official news & designations.

 - Comet Discoveries

July 18  Discovery of C/2016 N4 (MASTER)

 - Comet Recoveries

July 04 Recovery of P/2009 K1 (GIBBS) as P/2016 M2
July 04 Recovery of P/2008 J3 (McNAUGHT) as P/2016 N1
July 06 Recovery of P/2008 T1 (BOATTINI) as P/2016 N2
July 18 Recovery of P/2007 R3 (GIBBS) as P/2016 N3

- Other news

July 11 An international team of astronomers discovered a new dwarf planet orbiting in the disk of small icy worlds beyond Neptune. Designated 2015 RR245 by the International Astronomical Union's Minor Planet Center, it was found using the Canada-France-Hawaii Telescope on Maunakea, Hawaii,  as part of the ongoing Outer Solar System Origins Survey (OSSOS).  The Minor Planet Center describes the object as the 18th largest in the Kuiper Belt. Click on the image below to see a bigger version of the rendering of the orbit of RR245 (orange line). Objects as bright or brighter than RR245 are labeled. The blue circles show the projected orbits of the major planets.

Credit: Alex Parker - OSSOS team.

July 16 The Team Radar at Arecibo observed the Near-Earth asteroid (154244) 2002 KL6. This asteroid was discovered by Near-Earth Asteroid Tracking (NEAT) program in May 2002. It approached Earth to within 0.07 au (27 lunar distances) on July 22, 2016. Its absolute magnitude is around 17.4, which suggests a diameter within a factor of two of 1 km, assuming an optical albedo of 18%. Its rotation period is around 4.6 h based on lightcurves. 

Near-Earth asteroid 2002 KL6 observed by #TeamRadar at @AreciboRadar - gif animation by @benjaminsharkey #astronomy pic.twitter.com/UFsWqkErMN

— Ernesto Guido (@comets77) 16 luglio 2016

July 27 Rosetta is set to complete its mission in a controlled descent to the surface of its comet on 30 September. The mission is coming to an end as a result of the spacecraft’s ever-increasing distance from the Sun and Earth. "It is heading out towards the orbit of Jupiter, resulting in significantly reduced solar power to operate the craft and its instruments, and a reduction in bandwidth available to downlink scientific data.  Instead of risking a longer hibernation that is unlikely to be survivable, and after consultation with Rosetta’s science team in 2014, it was decided that Rosetta would follow its lander Philae down onto the comet. The final hours of descent will enable Rosetta to make many once-in-a-lifetime measurements, including very-high-resolution imaging, boosting Rosetta’s science return with precious close-up data achievable only through such a unique conclusion." In the meantime Rosetta is still observing the comet. Below you can see comet 67P imaged by the OSIRIS instrument on 27 July 2016 from a distance of 8km. Click onthe image for a bigger version.

Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

by Ernesto Guido

Comets & Asteroids - Summary for June 2016

During the month of June 2016,  2 new comets were discovered and there was 1 comet recovery. A small asteroid, 2016 HO3, has been discovered in an orbit around the sun that keeps it as a constant companion of Earth, and it will remain so for centuries to come. On June 2nd a small asteroid (1-3 meters wide) hit Earth's atmosphere and exploded over Arizona. Amateur astronomer and comet discoverer Rolf G. Meier died on June 26th, 2016 after a short battle with cancer. "Current comet magnitudes" & "Daily updated asteroid flybys" pages are available at the top of this blog (or just click on the underline text here).

The dates below refer to the date of issuance of CBET (Central Bureau Electronic Telegram)  which reported the official news & designations.

- Comet Discoveries

June 05  Discovery of C/2016 K1 (LINEAR)

June 24  Discovery of C/2016 M1 (PANSTARRS)

- Comet Recoveries

June 06 Recovery of P/2010 N1 (WISE) as P/2016 GE_216

- Other news

June 02 On June 2nd at 3:56 a.m. local (MST) time (10:56 UT), a small asteroid (estimated diameter about 1-3 meters) hit Earth's atmosphere and exploded over Arizona. The airburst shook the ground below and produced a flash of light 10x brighter than a full Moon. A week later, one of Arizona State University’s top meteorite experts was off on a team expedition in the Arizona wilderness on an Apache homeland, braving bug bites, bears and mountainous terrain. After three nights camping and 132 hours of searching, the team found 15 meteorites, ranging in size from a medium-sized strawberry to a pea. A video with more info on this expedition is available here.

Credit: Mike Lerch on June 2, 2016 @ Front yard of home in Phoenix Az USA

Credit: Charlie Leight/ASU Now

June 15 A small asteroid, 2016 HO3, has been discovered in an orbit around the sun that keeps it as a constant companion of Earth, and it will remain so for centuries to come. This asteroid, first spotted on April 27, 2016, by the Pan-STARRS 1 survey, measures between 40 and 100 meters (120 to 300 feet) in diameter and it poses no threat to Earth.  As it orbits the sun, this new asteroid, designated 2016 HO3, appears to circle around Earth as well. It is too distant to be considered a true satellite of our planet, but it is the best and most stable example to date of a near-Earth companion, or "quasi-satellite."

Credit: NASA/JPL-Caltech 

It became a quasi-satellite about a century ago, and will follow our planet around the Sun for the next three centuries, looping around us once a year. Its yearly loop will then unhook from Earth, starting to follow a horseshoe path with respect to our planet, which will last for several millennia. In this animated picture below by A. Vitagliano, the frame is rotated synchronously with the revolution of Earth, which therefore moves along the short green segment located 1 AU above the Sun, while the other inner planets are hidden. The yellow loop represents one yearly path of the asteroid, and each frame is taken at 1 year intervals for a total span of 999 years. 

Credit: Aldo Vitagliano - Solex

June 26 Amateur astronomer and comet discoverer Rolf G. Meier (1953–2016) died on June 26th after a short battle with cancer. He was the discoverer of four comets which bear his name (Meier 1978, 1979, 1980, 1984). He received the RASC’s Chant Medal in 1979 for his contributions.

Rolf Meier with the 40cm Ottawa Centre telescope

by Ernesto Guido

New Comet: C/2016 K1 (LINEAR)

CBET nr. 4282, issued on 2016, June 05, announces the discovery of an apparently asteroidal object (magnitude ~18.5) found on CCD images taken on May 31 with the 3.5-m f/1 Space Surveillance Telescope on Atom Peak in the White Sands Missile Range, NM, USA, in the course of the LINEAR survey. This object has been found to cometary appearance by CCD astrometrists elsewhere after it was posted on the Minor Planet Center's NEOCP webpage. The new comet has been designated C/2016 K1 (LINEAR).

We performed follow-up measurements of this object, while it was still on the neocp. Stacking of 10 unfiltered exposures, 120 seconds each, obtained remotely on 2016, June 04.4 from H06 (iTelescope network - New Mexico) through a 0.43-m f/6.8 astrograph + CCD + f/4.5 focal reducer, shows that this object is a comet with a compact coma nearly 8 arcsec in diameter elongated toward PA 225.

Our confirmation image (click on it for a bigger version)

M.P.E.C. 2016-L34 assigns the following preliminary parabolic orbital elements to comet C/2016 K1: T 2016 July 14.36; e= 1.0; Peri. = 18.66; q = 2.29;  Incl.= 90.94

by Ernesto Guido

Comets & Asteroids - Summary for May 2016

During the month of May 2016,  3 new comets were discovered and cometary activity was detected for 1 previously discovered object (earlier designated as an asteroid). 

NASA's Hubble Space Telescope imaged comet 252P/LINEAR just after it swept by Earth on March 21, 2016 while the Subaru Telescope serendipitously captured high-resolution images of comet 67P/Churyumov-Gerasimenko. Moreover a non-gravitational acceleration has been detected influencing the motion of minor planet (85990) (see below for more about these news). "Current comet magnitudes" & "Daily updated asteroid flybys" pages are available at the top of this blog (or just click on the underline text here).

The dates below refer to the date of issuance of CBET (Central Bureau Electronic Telegram)  which reported the official news & designations.

- Comet Discoveries

May 09  Discovery of P/2016 J1 (PANSTARRS)*

May 09  Discovery of C/2016 J2 (DENNEAU)
May 31  Discovery of P/2016 J3 (STEREO)

* According to the discovery CBET,  follow-up images obtained at the 3.6-m Canada-France-Hawaii Telescope atop Mauna Kea on May 6.43 showed a second comet in the field. "The two components are moving at nearly identical rates in nearly identical directions (both about 0".6/minute in p.a. about 314 deg). The brighter component (designated component A) displays a clear and quite thin tail about 10" long in p.a. 250 deg in the May 6.43 images.  The fainter object (designated component B) also displays a clear but broader tail of similar length, oriented toward p.a. about 210 deg". The available astrometry for both components and ephemerides appear on MPEC 2016-J90

- Cometary activity detected

May 29  Cometary activity detected in 2016 KA = C/2016 KA (CATALINA)

Credit: P. Birtwhistle 

- Other news

May 12  Astronomers using NASA's Hubble Space Telescope captured images of comet 252P/LINEAR just after it swept by Earth on March 21.

Credit: NASA, ESA, and J.-Y. Li (Planetary Science Institute)

May 12 Hyper Suprime-Cam on the Subaru Telescope serendipitously captured high-resolution images of comet 67P/Churyumov-Gerasimenko during the inaugural queue-mode observations last March. The camera was scheduled to observe a distant compact galaxy when the chance came up to capture a view of the comet, and the images reveal fine details in the comet's coma and tails.

Credit: Subaru Telescope, NAOJ

May 25 Animation of the yearly discovery rate of #NEOs by size (H). Data from @MinorPlanetCtr via @JLGalache

May 27 CBET 4279 reports that a non-gravitational acceleration has been detected influencing the motion of minor planet (85990)

And finally a cartoon by the illustrator and cartoonist Tom Gauld + a Chelyabinsk event mention in "Zero K", the new novel by Don DeLillo (h/t to Paolo Simonetti) 

Credit: Tom Gauld

Credit: Don DeLillo

Credit: Don DeLillo

by Ernesto Guido

Comets & Asteroids - Summary for April 2016

During the month of April 2016,  2 new comets were discovered and cometary activity was detected for 1 previously discovered object (earlier designated as an asteroid). NASA's Hubble Space Telescope spotted a small, dark moon orbiting Makemake, the second brightest icy dwarf planet — after Pluto — in the Kuiper Belt. Pioneer comet observer Elizabeth (Pat) Roemer died on April 09. Moreover the discovery of the binary nature of asteroid (5674) Wolff and the images of a new satellite of asteroid (130) Elektra have been reported (see below for more about these news). "Current comet magnitudes" & "Daily updated asteroid flybys" pages are available at the top of this blog (or just click on the underline text here).

The dates below refer to the date of issuance of CBET (Central Bureau Electronic Telegram)  which reported the official news & designations.

- Comet Discoveries

Apr 05  Discovery of P/2016 G1 (PANSTARRS)

Apr 08  Discovery of P/2015 HG_16 (PANSTARRS)*

*G. V. Williams, Minor Planet Center, noted that the 2016 April 3 observations of  this comet appeared to belong to a supposedly asteroidal object found a year ago by Pan-STARRS1 on 2015 Apr. 20, 21, and 24 (and then given the minor-planet designation 2015 HG_16 on MPS 603395 and 603396)

- Cometary activity detected

Apr 24  Cometary activity detected in 2015 WZ = C/2015 WZ (PANSTARRS)

- Other news 

Apr 09  Pioneer comet observer Elizabeth (Pat) Roemer died on April 09. Astronomer Jim Scotti wrote this memory on Facebook: "With great sadness I must report the death of my friend and mentor Elizabeth (Pat) Roemer (1929-2016) this morning. She joined the Lunar and Planetary Lab in 1966. She led the world in the observation of faint comets and recovered 79 short period comets in an age where computing ephemerides and reducing astrometric observations were all done by hand. I learned so much from her beginning in Astronomy 400b which emphasized planetary astronomy and introductory celestial mechanics and was always a great help in later years in learning how to observe comets and asteroids".

Apr 23  CBET 4272 reports that minor planet (5674) Wolff is a binary system with an orbital period of 93.7 +/- 0.2 hr. Mutual eclipse/occultation events that are up to 0.70-magnitude deep indicate a lower limit on the secondary-to-primary mean-diameter ratio of 0.80.  

Apr 25  Astronomers have discovered a new satellite orbiting the main belt asteroid (130) Elektra (first announced via CBET 4036 on December 17, 2014). The team, led by Bin Yang (ESO, Santiago, Chile), imaged it using the extreme adaptive optics instrument, SPHERE, installed on the Unit Telescope 3 of ESO’s Very Large Telescope at Cerro Paranal, Chile. This new, second moonlet of (130) Elektra is about 2 kilometres across and has been provisionally named S/2014 (130) 1, making (130) Elektra a triple system. Exploiting the unprecedented sensitivity and spatial resolution of the instrument SPHERE, the team also observed another triple asteroid system in the main belt, (93) Minerva. Full paper now available here

Credit: Yang/ESO

Apr 26  NASA's Hubble Space Telescope has spotted a small, dark moon orbiting Makemake, the second brightest icy dwarf planet — after Pluto — in the Kuiper Belt. The moon — provisionally designated S/2015 (136472) 1 and nicknamed MK 2 — is more than 1,300 times fainter than Makemake. MK 2 was seen approximately 21,000 km (13,000 miles) from the dwarf planet, and its diameter is estimated to be 161 km (100 miles) across. Makemake is 1400 km (870 miles) wide. The dwarf planet, discovered in 2005, is named for a creation deity of the Rapa Nui people of Easter Island.

Credit: NASA, ESA, Parker & Buie (SRI), Grundy (Lowell Obs), K. Noll (NASA GSFC)

by Ernesto Guido

Comets & Asteroids - Summary for March 2016

During the month of March 2016,  3 new comets were discovered. On March 17, 2016 a new impact flash on Jupiter has been captured by amateur astronomers. Moreover, delay-doppler images of asteroid 2016 DV1 (on March 03, 2016) and of comet P/2016 BA14 (on March 22, 2016) have been obtained by Goldstone Solar System Radar.(see below for more about these news). "Current comet magnitudes" & "Daily updated asteroid flybys" pages are available at the top of this blog (or just click on the underline text here).

The dates below refer to the date of issuance of CBET (Central Bureau Electronic Telegram)  which reported the official news & designations.

 - Comet Discoveries

Mar 11  Discovery of C/2016 E1 (PANSTARRS)
Mar 16  P/2015 B4 (LEMMON-PANSTARRS)
Mar 16  C/2016 E2 (KOWALSKI)

Scientists using the Goldstone Solar System Radar in California's Mojave Desert observed comet P/2016 BA14 during its historic flyby. Close approach of March 22, 2016 by P/2016 BA14 has been the third closest on record and the closest flyby of a comet in 246 years (for more info about P/2016 BA14 see our previous post). Radar images from the flyby indicate that the comet is about 1 kilometer in diameter. Moreover data collected by V. Reddy using the NASA Infrared Telescope Facility (IRTF) on Mauna Kea, Hawaii indicate that the comet reflects less than 3 percent of the sunlight that falls on its surface. 

Radar images of comet P/2016 BA14 - Credit: NASA/JPL-Caltech/GSSR

Comet P/2016 BA14 - Credit: NASA/JPL-Caltech/GSSR

- Asteroid & Meteors news

On March 17, 2016 (at 00:18:35UT) a possible impact flash on Jupiter was imaged independently by 2 amateur astronomers: Gerrit Kernbauer (Mödling, Austria) & John McKeon (Dublin, Ireland). Both videos are on Youtube: bit.ly/1RwXOZb & bit.ly/1RwXOZc. If confirmed, this becomes the fifth such event in the past decade. For more info about old impact flashes see our previous post here. Click on the gif below to see a comparison side by side of the 2 videos with an apparent impact flash on the Jupiter's East limb. 

Credit: Kernbauer & McKeon

Credit: John McKeon

On March 03, 2016, delay-doppler images of asteroid 2016 DV1 were obtained using DSS-13 to transmit and GBT to receive. The images span ~1 rotation. Rotation period is about 304 +/-8 seconds.

Goldstone Radar Observations of 2016 DV1

by Ernesto Guido

New Comet: C/2016 E2 (Kowalski)

CBET nr. 4266, issued on 2016, March 16, announces the discovery of a comet (magnitude ~18) by R. A. Kowalski on CCD images obtained with the 0.68-m Schmidt telescope in the course of the Catalina Sky Survey on Mar. 15.44-15.46 UT. The new comet has been designated C/2016 E2 (Kowalski).

We performed follow-up measurements of this object, while it was still on the neocp. Stacking of 65 unfiltered exposures, 15 seconds each, obtained remotely on 2016, March 16.3 from H06 (iTelescope network - New Mexico) through a 0.25-m f/3.4 reflector + CCD, shows that this object is a comet with a diffuse irregular coma nearly 10 arcsec in diameter.

Our confirmation image (click on it for a bigger version)

M.P.E.C. 2016-F03  assigns the following preliminary parabolic orbital elements to comet C/2016 E2: T 2016 Feb. 6.70; e= 1.0; Peri. =  322.01; q = 1.07;  Incl.= 136.00

Credit: JPL

This comet will have a close approach with Earth at about 114 LD (Lunar Distances = ~384,000 kilometers) or 0.2920 AU (1 AU = ~150 million kilometers) on March 17, 2016 at 06:41 UT (it passed perihelion on Feb. 06, 2016 at 1.075 AU). Comet C/2016 E2 will fade in the coming days as its distance from both the Earth and Sun increase.


by Ernesto Guido & Nick Howes

Comets & Asteroids - Summary for February 2016

During the month of February 2016,  3 new comets were discovered, there were 2 recoveries and cometary activity was detected for 2 previously discovered objects (earlier designated as asteroids). New fragments of comet  P/2015 Y2 = P/2010 V1 (IKEYA-MURAKAMI) (see previous post) reported. According to a paper available on Arxiv, at least 17 fragments have been identified. Moreover the binary nature of asteroid (2535) Hämeenlinna and a previously unknown shower of naked-eye meteors, now known as the Volantids, have been reported (see below for more about these news). "Current comet magnitudes" & "Daily updated asteroid flybys" pages are available at the top of this blog (or just click on the underline text here).

The dates below refer to the date of issuance of CBET (Central Bureau Electronic Telegram)  which reported the official news & designations.

- Comet Discoveries

Feb 14  Discovery of C/2016 C1 (PANSTARRS)

Feb 15  Discovery of P/2016 BA14 (PANSTARRS)*

Feb 19  Discovery of C/2016 C2 (NEOWISE)

Comet P/2016 BA14 - M.Kelley/S.Protopapa/UMD

*The comet 252P/LINEAR will pass perihelion on 2016 Mar. 15 and make an historic close approach to the Earth on 2016 March 21 at 0.036 AU (or 13.9 LD), which is one of the closest cometary approaches to the Earth on record. In the meantime, on 2016 Jan 22, asteroid 2016 BA14 was discovered by the Pan-STARRS survey and it will have a close approach with Earth on 2016 March 22 at 0.0237 (or 9.2 LD). This asteroid and comet 252P have very similar orbital elements (a fact first noted by D. Denisenko on Comets Mailing List). This similarity prompted observers to image asteroid 2016 BA14 with the 4.3-m Lowell Observatory's Discovery Channel Telescope that led to the discovery of its cometary activity (new designation P/2016 BA14).  Close approach by P/2016 BA14 will be the third closest on record and the closest flyby of a comet in 246 years (since the 1770 passage by Comet D/1770 L1 -Lexell- at 5.9 LD). These objects are very probably related to one another, fragments from a past larger comet; observations in program (by the way also with the HST space telescope) will provide further confirmation.

Credit: http://neo.jpl.nasa.gov/ca/

- Comet Recoveries

Feb 06  Recovery of P/2008 Y2 (GIBBS) as P/2016 A9

Feb 15  Recovery of P/2006 G1 (McNAUGHT) as P/2016 B2

- Cometary activity detected

Feb 01  Cometary activity detected in 2015 ER61 = C/2015 ER61 (PANSTARRS)

Feb 02  Cometary activity detected in 2015 PD229 = P/2015 PD229 (ISON-Cameron) 

Comet P/2015 PD229 (ISON-Cameron) - NOAO DECam DECAL

- Asteroid & Meteor news

Feb 20  CBET 4261 reports that CAMS video camera surveillance of meteor showers in the Southern Hemisphere (CAMS New Zealand) detected a previously unknown shower of naked-eye meteors that peaked at the time of the local new year's eve celebrations. One out of three meteors that night came from this shower. The new shower is now known as the Volantids, named after the constellation Volans, the flying fish, from where the meteoroids appear to approach us. The parent body has not yet been identified. The source is a Jupiter-family comet that must now be in a relatively highly inclined orbit. A copy of the paper submitted to for publication in WGN, the Journal of the International Meteor Organization (JIMO) is available here.

Direction from which meteors approached us on December 31 (and next night). Credit: CAMS

Feb 25  CBET 4262 reports that minor planet (2535) Hämeenlinna is a binary system with an orbital period of 21.23 +/- 0.01 hr.  The primary shows a period of 3.23106 +/- 0.00006 hr and has a lightcurve amplitude of 0.10 mag at solar phases 2-8 degrees, suggesting a nearly spheroidal shape.

by Ernesto Guido