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

Follow-up of recent NEOCP objects from OASDG L07

Below you can find a selection 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.

2020 VX5 (neocp designation C3WZUQ2) is an Apollo-type asteroid discovered by G96 Mt. Lemmon Survey on November 15, 2020. This asteroid has an estimated size of 55 m - 120 m (H=23.4) and it had a close approach with Earth at about 29 LD (Lunar Distances = ~384,000 kilometers) or 0.074 AU (1 AU = ~150 million kilometers) at 1950 UT on 11 Nov. 2020.

2020 VN1 (neocp designation A10sCsG) is an Aten-type asteroid discovered by T05 ATLAS-HKO, Haleakala on November 10, 2020. This asteroid has an estimated size of 7.3 m - 16 m (H=27.8) and it had a close approach with Earth at about 1.19 LD (Lunar Distances = ~384,000 kilometers) or 0.00306 AU (1 AU = ~150 million kilometers) at 0757 UT on 07 Nov. 2020.

2020 VF1 (neocp designation X71128) is a Centaur-type object discovered by D29 Purple Mountain Observatory, XuYi Station on November 08, 2020. At the discovery time it was at about 9.7 AU from the Sun.

2020 VM1 (neocp designation P219ias) is an Apollo-type asteroid discovered by F52 Pan-STARRS 2, Haleakala November 08, 2020. This asteroid has an estimated size of 190 m - 420 m (H=20.8) and it had a close approach with Earth at about 73 LD (Lunar Distances = ~384,000 kilometers) or 0.18 AU (1 AU = ~150 million kilometers) at 2033 UT on 01 Nov. 2020.

by Ernesto Guido

Asteroid (99942) Apophis

Asteroid (99942) Apophis was discovered on 2004 June 19 by R. A. Tucker, D. J. Tholen and F. Bernardi at Kitt Peak and then lost until it was serendipitously recovered in December of 2004. This Aten class asteroid, approximately 270 meters in diameter, caused a brief period of concern in December 2004 because initial observations indicated a small probability that it would strike the Earth in 2029. Thanks to additional observations, the 2029 threat was eventually ruled out. However, a possibility remained that during the 2029 close encounter with Earth, Apophis would pass through a gravitational  keyhole, a precise region in space no more than about a 600 meters wide, that would set up a future impact on 2036. The principal source of uncertainty is the acceleration due to the Yarkovsky effect, a non-gravitational effect that is a function of the asteroid's rotation period, pole direction, thermal properties, mass, shape, and dimensions. So this asteroid continues to receive considerable attention from amateur and professional astronomers.  

Apophis became (on 2004) the first object rated level 2 on the Torino scale, and for only a short time it was subsequently upgraded to level 4, the record for highest Torino rating. Currently Apophis has been downgraded to 0 in the Torino scale (the currently  highest-scaled objects are 2007 VK184 & 2011 AG5 at level 1).

The following citation is from MPC 54567: "(99942) Apophis = 2004 MN4. Also known as Apep, the Destroyer, Apophis is the Egyptian god of evil and destruction who dwelled  in eternal darkness.  As a  result of its passage within 40 000 km of the earth on 2029 Apr. 13, this minor planet will move from the Aten to the Apollo  class."

Apophis will make a very close Earth approach on April 13, 2029 at 2146UT when it will pass within 0.1 LD (Lunar Distances = ~384,000 kilometers)  or 0.00025 AU (1 AU = ~150 million kilometers). This will be the closest approach by something this large currently known. During the 2029 approach, Apophis' brightness will peak at magnitude 3.3, so it will be visible to the naked eye.

Before the 2029 encounter, Apophis will have a close approach with our planet on January 2013.  Actually, (99942) Apophis will have a close approach with Earth at about 37.6 LD (Lunar Distances = ~384,000 kilometers) or 0.0967 AU (1 AU = ~150 million kilometers) at 1143 UT on Jan. 09, 2013. On that date, the asteroid will reach the magnitude ~15.8 while moving at ~ 3.49"/min. According to Giorgini et al. (2008), it's likely that radar astrometry in 2013 will shrink the uncertainties sufficiently to completely rule out an impact in the 2030s.

We performed some follow-up measurements of this object just few weeks before its 2013 close approach, from the H06 ITelescope network (near Mayhill, NM) on  2012, Dec. 13.4, through a 0.25-m f/3.4 reflector + CCD. Below you can see our image, 19x30-second exposures, taken with the asteroid at magnitude ~17.5 and moving at ~2.57"/min. Click on the image below to see a bigger version. North is up, East is to the left.

Below you can see a short animation showing the movement of (99942) Apophis (each frame is a stack of 19x30-second exposures). North is up, East is to the left. Click on the thumbnail for a bigger version:

UPDATE - January 11, 2013

ESA’s Herschel space observatory made new observations of asteroid Apophis as it approached Earth this weekend. The data shows the asteroid to be bigger than first estimated, and less reflective. "Herschel provided the first thermal infrared observations of Apophis at different wavelengths, which together with optical measurements helped refine estimates of the asteroid’s properties. Previous estimates bracketed the asteroid’s average diameter at 270 ± 60 m; the new Herschel observations returned a more precise diameter of 325 ± 15 m".  The image below shows the asteroid in Herschel’s three PACS wavelengths: 70, 100 and 160 microns, respectively (click on it for a bigger version). For more info about Herschel's find click here.

Credit: ESA/Herschel/PACS/MACH-11/MPE/B.Altieri (ESAC) and C. Kiss (Konkoly Observatory)

After tracking asteroid 99942 Apophis with NASA's Goldstone radar dish, astronomers are now certain that the threatening asteroid has essentially no chance of striking Earth in 2036. See S&T article here for more details.

by Ernesto Guido & Nick Howes

2011 GP59 - Close Approach

The Mpec circular 2011-G60 issued on April 09, 2011 announced the discovery of a new Aten asteroid officially designated 2011 GP59. This asteroid (~ magnitude 17.5) was discovered by La Sagra Survey through their 0.45-m f/2.8 reflector + CCD, on images obtained on April 08.9, 2011. After posting on the Minor Planet Center's 'NEOCP' webpage, other CCD astrometrists have been able to follow-up the new object to define its orbit.

According to the preliminay orbit, 2011 GP59 is an Aten type asteroid. This class of asteroids are defined by having semi-major axes of less than one astronomical unit (the distance from the Earth to the Sun). 2011 GP59 will have a close approach with Earth on April 15, 2011 at 1909 UTC at rougly 0.003567AU or 1.39 LD (Lunar Distance) reaching the magnitude ~13. Its absolute magnitude H=24.30 correspond to an approximate diameter of 50 meters.

2011 GP59 shows evident magnitude fluctuations. Below you can see a light-curve made by Brian Skiff (Lowell Observatory): 6-hours of observations using the Lowell 0.55-m Schmidt with 45-second exposures showing an amplitude in excess of 2 full magnitudes over a period of roughly 7.5 minutes.

(Credit: Brian Skiff - Lowell Observatory)

We have been able to follow 2011 GP59 on April 12.35 remotely from the GRAS Observatory (near Mayhill, NM) through a 0.25-m, f/3.4 reflector + CCD. Below you can see an animation showing the fast movement (the object was moving at 10.5 "/min) of 2011 GP59 on the sky on April 12, 2011. Each frame is a stack of 2x20-second exposure. The asteroid is moving from the top left corner to the bottom right corner. In the animation you can easily see the rapid brightness fluctuations of this object.

Click on the thumbnail below to see the animation:

UPDATE - April 14, 2011 - 13:30UT

We imaged 2011 GP59 on April 14.36, 2011 remotely from the GRAS Observatory (near Mayhill, NM) through a 0.51-m, f/6.9 reflector + CCD.

It's a single unfiltered exposure of 600 seconds, showing 2011 GP59 as trail with brightness fluctuations clearly evident (click on the image for a bigger version) :



by Ernesto Guido & Giovanni Sostero