Follow-up of recent NEOCP from OASDG L07 - Part II

Below you can find a new selection (part I available here) of some objects for which we recently made follow-up observations at the "Osservatorio Salvatore di Giacomo, Agerola, ITALY" (MPC code L07; Observers E. Guido, A. Catapano, F. Coccia) while they still were on the NEOCP list. More details about the telescope, the  magnitude, number of images & exposition, asteroid speed & PA etc. are on the images. Click on each image for a bigger version. All the processing has been made with TYCHO software by D. Parrott.

COMET C/2020 V2 (ZTF), (neocp designation ZTF0G6I). Stacking of 25 unfiltered exposures, 120 seconds each, obtained remotely on 2020, Nov. 19.1 from L07 (Osservatorio Salvatore di Giacomo, Agerola) through a 0.5 m f/8 Ritchey Chretien + CCD, showed that this object is a comet with a diffuse coma about 7" in diameter and FWHM 3.3" compared to the average value of 2.1" for the stars of same magnitude.

 

2020 WH1 (neocp designation SaSza42) is an Apollo-type asteroid discovered by K88 GINOP-KHK, Piszkesteto, observer R. Szakats on November 17, 2020. This asteroid has an estimated size of 33 m - 73 m (H=24.6) and it had a close approach with Earth at about 11.5 LD (Lunar Distances = ~384,000 kilometers) or 0.029 AU (1 AU = ~150 million kilometers) at 0824 UT on 09 Nov. 2020.

 

2009 WY7 (neocp designation Sar2518) is an Aten-type asteroid (First observed at Lincoln Laboratory ETS, New Mexico on 2009-11-19) recovered by K88 GINOP-KHK, Piszkesteto, observer K. Sarneczky on November 22, 2020. This asteroid has an estimated size of 40 m - 90 m (H=24.1) and it had a close approach with Earth at about 20.17 LD (Lunar Distances = ~384,000 kilometers) or 0.05184 AU (1 AU = ~150 million kilometers) at 1104 UT on 24 Nov. 2020.

 

2020 WO3 (neocp designation C3ZZY12) is an Aten-type asteroid discovered by G96 Mt. Lemmon Survey on November 22, 2020. This asteroid has an estimated size of 67 m - 150 m (H=23.0) and it had a close approach with Earth at about 40.26 LD (Lunar Distances = ~384,000 kilometers) or 0.10345 AU (1 AU = ~150 million kilometers) at 1911 UT on 28 Nov. 2020.

 

 

COMET P/2005 CR16 = P/2003 WR168 = P/2020 W2 (NEAT-LINEAR) - (neocp designation C3XUF62). It is a comet discovered in survey images taken by Mount Lemmon Survey (G96) obtained on Nov. 16 UT. Subsequent follow-up astrometry and improved orbits allowed the MPC to find prediscovery positions and link the object to multi-opposition minor planet 2005 CR16 = 2003 WR168.

 

2020 WW3 (neocp designation C417PE2) is an Aten-type asteroid discovered by G96 Mt. Lemmon Survey on November 24, 2020. This asteroid has an estimated size of 20 m - 45 m (H=25.6) and it had a close approach with Earth at about 9.12 LD (Lunar Distances = ~384,000 kilometers) or 0.02344 AU (1 AU = ~150 million kilometers) at 0243 UT on 23 Nov. 2020.

 

 by Ernesto Guido

New Comet: C/2010 E5 (SCOTTI)

IAU circular No. 9127, issued on 2010, March 17, announces the discovery by J. V. Scotti of a new comet on Mar. 14, 2010, in the course of the Spacewatch survey. After posting on the Minor Planet Center's NEOCP webpage, many observers have noted the cometary appearance of this 19.5 magnitude object, designated C/2010 E5 (SCOTTI).

We have been able to confirm this object remotely, through the GRAS network, using a scope located in Mayhill (NM): on 2010, March 17.4, co-adding of 20 unfiltered exposures, 120-seconds each obtained by means of a 0.25-m, f/3.4 reflector + CCD, show a coma nearly 10-arcsec in diameter, with a broad tail, about 25-arcsec long toward north-west.

Our confirming image:

The first and preliminary orbit for comet C/2010 E5 (Scotti) indicates perihelion on Jan. 20, 2011, at about 4.0 AU.

This is the 43rd comet for Spacewatch and the 5th for Scotti.

by Ernesto Guido & Giovanni Sostero

Recovery of P/2001 MD7 (LINEAR) = P/2009 F3 (LINEAR)

IAU Circular No. 9031, issued on 2009 Mar 20, announces the recovery of comet P/2001 MD_7 = COMET P/2009 F3 (LINEAR) by the undersigneds; it was last observed in April 2002.

We picked up this object on 2009 Mar 17, 18 and 20 through a couple of remotely controlled telescopes, located in New Mexico and Australia. The comet appeared as a pale glow, magnitude about 18, nearly 15 arcsec in diameter.

The recovered comet was very close to the ephemerids positions, however its detection has been a little problematic, because it was rather low in the morning sky just before twilight, located in a rich star field in Sgr. We took several nights of observations to locate it, fighting with clouds and moonlight interference.

Here you can see our image of March 22, 2009:

http://tinyurl.com/czgnts

According the orbital elements published by the Minor Planet Center, perihelion will occur in September 2009, with the comet at 1.25 AU from the Sun; at that time P/2009 F3 (LINEAR) will reach about magnitude 12. This object moves along an elliptic orbit in 7.9 years, having a semi-major axis of 3.97 AU, eccentricity of 0.68 and an inclination nearly 13.5 deg.

We thanks the Mayhill-GRAS and Grove Creek-Skylive staff for the kind support they provided us for this tricky recovery.

by Ernesto Guido, Giovanni Sostero & Paul Camilleri

Foreshortening effects on C/2007 N3 (LULIN)

Comet C/2007 N3 (LULIN) was a nice show in late February this year, when it passed relatively close (nearly 0.42 AU, on Feb. 24th). At about its perigee, another phenomena occurred: its phase angle reached a minimum value, then it quickly started to grow-up again. Nearly simultaneosly we witnessed an abrupt change in the appearance of the comet, due to the consequent foreshortening effect: the ion tail, in a matter of hours, switched from North-West to South-East.

Possibly another, less cospicuous, change in comet's LULIN aspect may be under course: according to our follow-up, some effects of the foreshortening change seems to be readily visible also in a series of images we secured from various sites & through with different scopes, in the past few weeks.

As you may notice from the following panels, the prominent feature (kind of "fan" structure) originating from the central condensation toward South-West (i.e. at about PA 220 deg), plus a secondary one, toward North-East (i.e. at about PA40 deg) that was reported by several observers, visible till March 2nd, now seems to be over:

March 11th: http://tinyurl.com/acq7wr

March 2nd: http://tinyurl.com/d8bnfc

Februaty 27th: http://tinyurl.com/cpslxs

February 19th: http://tinyurl.com/bgt6yd

More data need to be secured to definitely clarify the situation, however at a first glance we have the impression that this might be a foreshortening effects as well. Apparently, the changing geometry really plays a strong role, when interpreting the inner coma details sometimes reported on comets (alleged fans, jets, etc.).

by Giovanni Sostero, Ernesto Guido, Paul Camilleri & Virgilio Gonano

Curious coma-tail of C/2007 Q3 (Siding-Spring)

Recently we imaged C/2007 Q3 (Siding Spring), remotely with a "Skylive" scope from Grove Creek (Australia):

http://tinyurl.com/amgcvn

details on picture.

Through image processing, the comet show a funny effect: at low contrast, an asymmetric coma is seen, about 45 arcsec in diameter, with an obvious elongation toward (about) East (PA 90 deg). In high contrast, a broad tail, nearly 80 arcsec long, became obvious; but it points toward South-West, at about PA 230 deg (i.e., in nearly opposite direction)!

Further image processing, capable to extract possible inner coma features (azimuthal median subtraction, 1/r theoretical coma subtraction) confirms the presence of an asymmetric coma, with a possible feature exing toward East, North-East, developing in a counterclockwise direction.

Preliminary photometric analysis of our frames, show a total m1 magnitude of about 13, while the sharp central condensation shine at m2 about magnitude 15 (unfiltered CCD).

Comet C/2007 NQ3 (Siding-Spring) moves along a parabolic orbit, whose perihelion will be reached in October 2009, at 2.2. AU from the Sun.

Updated orbital elements and ephemerids are available in the Minor Planet Center's Website:

http://tinyurl.com/bgbme8

by Giovanni Sostero, Ernesto Guido & Paul Camilleri

Changing geometry of comet C/2007 N3 (LULIN)

During the past few nights, we witnessed a dramatic change of the viewing geometry of comet C/2007 N3 (LULIN): its ion tail switched its position from North-West, and is currently hidden behind the coma. However this phenomena doesn't change that much the visibility of some details within the inner coma of the comet.

Here you can find an image obtained on 2009, Feb. 27 (details in caption):

Comparison with a similar image, obtained on 2009, Feb. 19 (details in caption):

shows the persistence of some asymmetries in the inner coma. In particular, a kind of "fan" toward PA 200 deg, with a second, similar structure (but less evident) in the opposite direction, toward PA 20 deg. It's not clear yet the explanation of this features; what we can say at the moment, is that they doesn't seem to be artefacts (i.e. artificially generated features using image processing softwares) and that they show no significant changes in spite of the significative change of our perspective angle.

by Ernesto Guido, Giovanni Sostero and Paul Camilleri

2009 AU1

This interesting object has been discovered on 2009 Jan 03 by the Italian amateur Fabrizio Tozzi, remotely through the Sierra Stars 0.60-m reflector, and confirmed at first by himself, using other remotely controlled scopes of the "Skylive" network, located in Sicily and Australia.

The preliminary orbital elements available published on MPEC 2009-A48 report e~0.5, a~4.6 and Incl.~ 26 deg; this is a very comet-like orbit! The object passed perihelion on July-August 2008, and at the moment of discovery it was located in Orion, at about magnitude 18.

We performed some follow-up of it while it was posted in the NEO-CP webpage; in our stacking (20 x 120 sec unfiltered exposures) we cannot distinguish any coma and/or tail, the FWHM of 2009 AU1 being very similar to that of the nearby field stars.

Our image is available here:

http://tinyurl.com/77hwuj

Anyway congratulations to Fabrizio for his interesting find.

by Ernesto Guido, Giovanni Sostero and Paul Camilleri