New discovered PHA: 2011 GM44

The Mpec circular 2011-G45 issued on April 06, 2011 announced the discovery of a new PHA asteroid officially designated 2011 GM44. This asteroid (~ magnitude 16) was discovered by R. H. McNaught through the 0.5-m Uppsala Schmidt telescope at Siding Spring, on images obtained on April 05.4, 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 GM44 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). It is also flagged as a "Potentially Hazardous Asteroid". PHA are asteroids larger than approximately 100m that might have threatening close approaches to the Earth (they can come closer to Earth than 0.05 AU)

2011 GM44 had a close approach with Earth on April 01, 2011 at rougly 0.0234AU.

We have been able to follow it while still on the neocp using a the Tzec Maun Foundation scope: the Takahashi TOA-150 f/7.3 refractor + CCD (located near Moorook, Australia).

Our confirming image (click on it for a bigger version):

Below you can see an animation showing the fast (the object was moving at 13.5 "/min) movement of 2011 GM44 on the sky on April 05, 2011. Each frame is a single 20-second exposure. Click on the thumbnail below to see the animation:

You can download the .avi file (~ 13 MB) here: http://ge.tt/5i4czE8

by Giovanni Sostero and Ernesto Guido

Observations of NEOs 2011 BB45 & 2011 BA45

In the past few days a number of faint objects discovered by Pan-STARRS (PS1 System - Haleakala - mpc code F51) have been added to the Neo Confirmation Page on the MPC website.

PS1 is a 1.8-m Ritchey-Chretien + CCD that, according to PS1SC Blog, "comes equipped with the worlds largest digital camera which has 1.4 billion pixels (over 250 times the number of pixels in an iPhone’s camera). This along with the telescope’s design allows it to observe with a three degree field of view (six full moons across)".

We have been able to follow a couple of these very faint objects using the 2.0-m Faulkes Telescope North (Haleakala - mpc code F65).

Below you can see the animations of 2011 BA45 (~ magnitude 19.8) & 2011 BB45 (~ magnitude 20.5 ) obtained on February 02, 2011:

Discovery mpecs:

Asteroid Type MOID H
2011 BB45 Amor 0.08815 19.6
2011 BA45 Apollo 0.11601 21.5

http://www.minorplanetcenter.org/mpec/K11/K11C05.html

http://www.minorplanetcenter.org/mpec/K11/K11C06.html


By Ernesto Guido, Nick Howes & Giovanni Sostero

2010 AL30 - Close approach Video & Image

Just few hours before the close approach of small asteroid 2010 AL30 to Earth at about 0.34 lunar-distance, we have been able to image it remotely through the GRAS network, using a scope located in Mayhill (New Mexico).

This is a single 120-second exposure showing the asteroid as a trail among the field stars (more details on image):

(click on the image for a bigger version )

While below you can see an animation composed of 6 frames, each frame is a 30-second exposure. Click on it for a bigger version:

by Ernesto Guido & Giovanni Sostero

NEO 2010 AL30 Close Approach

MPEC 2010-A59 issued on on 2010, Jan. 11 announces the discovery by Linear survey of a new object designated 2010 AL30. According to the preliminary orbit, 2010 AL30 will approach Earth at about 0.34 lunar-distance at 1248 UTC on 13 Jan. 2010 at magnitude 14 and it will be moving at about 10 arcsec/sec. We have been able to follow this object while it was on the Neocp.

Our image. Click on it for a bigger version:

The object has a value of H=27.0 (about 10/15 meters) and has an orbital period of 1.00 yr. On Minor Planet Mailing List, there was some early speculation that the object could be a man-made object rather than a natural one. But according to Alan W. Harris : "..it is unlikely to be artificial, it's orbit doesn't resemble any useful spacecraft trajectory, and its encounter velocity with the Earth is not unusually low, around 9.5 km/sec "v_infinity". Perfectly ordinary Earth-crossing orbit".

The radar team at Goldstone is attempting to schedule time for radar observations of 2010 AL30 early on January 13. The pointing uncertainties are currently large, so optical astrometry is required.

UPDATE - JANUARY 12, 2010

We have been able to follow-up 2010 AL30 on Jan. 12.37 through the GRAS network, using a scope located in Mayhill (NM). Below you can see our image obtained by co-adding of 16 unfiltered exposures, 10-seconds each obtained by means of a 0.25-m, f/3.4 reflector + CCD.

2010 AL30 has been classified in the JPL Small-Body Database as an Apollo-type asteroid. Apollo are Near-Earth asteroid with orbits that cross the Earth's orbit similar to that of 1862 Apollo.

Please see our new post for latest image & video of 2010 AL30 taken few hours before the close approach:

http://remanzacco.blogspot.com/2010/01/2010-al30-close-approach-video-image.html

by Ernesto Guido & Giovanni Sostero

New discovered PHA: 2009 ST19

This minor planet, belonging to the "Apollo" class, is also flagged as a "Potentially Hazardous Asteroid", an object that, because of its orbital parameters, might represent a possible threat of impact for planet Earth.

It has beeen discovered serendipitously by the Spanish amateur astronomer J. M. Bosch (Santa Maria de Montmagastrell, MPC#B74) on 2009, Sept. 16.2, ay magnitude about 17. At that time it was posted on the NEO-CP webpage of the Minor Planet Center as "jmbo11"; after a couple of days it was withdrawn, because it was not confirmed by any further observations.

On 2009, Sept. 22, the LINEAR sky survey picked-up a fast moving object, that was posted in the NEO-CP as "BQ24981". After some follow-up observations from various sites, on 2009 Sept. 23 the MPC published M.P.E.C. 2009-S72 informing that the two objects mentioned before were actually the same celestial body.

 
We performed some follow-up of this object on 2009, Sept.23.1, remotely from the Mayhill Station (NM) of the GRAS network. Click on the image below for a bigger version.

 

According to the NEODyS webpage this object. about 0.5-Km in diameter, made a close pass to Earth on 1980, Oct. 4, at a minimum possible distance of about 0.009 AU (nominal distance of about 0.04 AU).

Congratulations to J. M. Bosch for his find.

E. Guido, G. Sostero, P. Camilleri, M. Jaeger, E. Prosperi, W. Vollmann

Fly-by of the Apollo-type asteroid 2008 QS11

The asteroid 2008 QS11 has been discovered by the Siding Spring sky Survey (MPC code #E12) on 27 August 2008 at about magnitude 18.

The absolute magnitude of 19.8 suggests a diameter within a factor of two of 350 m (1). Due to its size and the proximity of its orbit to Earth's, this object has been classified as a "Potentially Hazardous Asteroid" by the Minor Planet Center. This object is also a target for the Goldstone Radar facility.

2008 QS11 (classified as an Apollo-type NEO) will reach on 02 October 2008 the minimum distance from Earth (0.02767 A.U.) with a maximum predicted brightness of about magnitude 14.

Here You can see the discovery mpec:

http://cfa-www.harvard.edu/mpec/K08/K08Q46.html

Below you can see our animation showing the motion of the asteroid in 30 minutes. At the moment of the shots 2008 QS11 was moving at 27"/min (magnitude 14):

UPDATE Radar image of 2008 QS11 from October 1: 0.125 usec (19 m) x 0.043 Hz

Range increases down and Doppler frequency increases to the right. The bandwidth is about 1 Hz and the visible extent is roughly 280 meters. Given that the radar can illuminate only about 1/2 of the object, its true size is thus about 560 meters.

Credit: JPL-NASA

By Ernesto Guido & Giovanni Sostero

The Virtual Impactor Minor Planet 2008 HJ

After its posting on the NEO Confirmation Page with the NEO-Confirmation Page with code BK08329, follow-up was secured by a number of observers, among which our osservatory (M.P.C. Code #473).

M.P.E.C. 2008-H26, issued on 2008 April 25 , 20:51 U.T. , has announced the discovery of 2008 HJ: this is the tempoarary designation of the object, by the M.P.C. observatory code #704 Lincoln Laboratory ETS.

After few days, the asteroid has been catalogued as a "virtual impactor", because it has a very little probability that its orbit could be a threat for our planet; however currently it is flagged with a level "0" in the Torino scale. This situation could change, so these kind of minor planets are kept under strict monitoring by two istitutions , that are collecting the updated astrometric measurements about 2008 HJ : the Neo Object Program and Neo Dys Risk Page.

As suggested by the Minor Planet Center, it is mandatory to perform futher follow-up of this asteroid in next months, in order to improve the knowledge of its orbit with new measures. This is important to reduce the uncertains on orbital parameters and to confirm that 2008 HJ really belongs to the 0 class of Torino scale, that rappresents a very low level of hazard.

The image below of 2008 HJ has been obtained by Remanzacco Observatory team in the same day of its discovery.

At the time of discovery, 2008 HJ had the smallest known rotation period in the Solar System, completing one revolution every 42.7 seconds (see lightcurve below).

Credit: R. Miles

by Ernesto Guido

Apollo asteroid 2008 HW1

M.P.E.C. 2008-H35, issued on 2008 Apr. 28, 18:44 UT, announces the discovery of 2008 HW1, an Apollo asteroid in a very comet-like orbit (Tj nearly 2.4; Jupiter family comets have Tisserand parameter TJ between 2 and 3). It was picked-up by the staff of Lincoln Laboratory ETS through a 1.0-m f/2.15 reflector + CCD, on 2008 April 25.35091. After its posting on the NEO Confirmation Page, further follow-up was secured by a number of observers. 

According the preliminary orbital elements published by the Minor Planet Center, 2008_HW1 moves along a very elongated orbit (e~0.96), that takes a little more than 4 years to be completed; at aphelion it approaches the orbit of Jupiter (Q~ 5 AU), while at perihelion (that will be reached in middle of next June) is passes only 0.1 AU - or nearly 15 Million Km - from the Sun. This is a rock whose diameter is supposed to range from nearly 600-m to 2-Km (depending on its surface reflectivity).

We performed some follow-up on 2008, April 28.0, from the Remanzacco Observatory (MPC #473):

In spite of its very comet-like orbit, in our stackings (total exposure time of 30 minutes) this object appears perfectly stellar, with no hints of any detectable coma or tail within our seeing limit.

by L. Donato, M. Gonano, V. Gonano, E. Guido, V. Santini and G. Sostero

Asteroid 2008 GS3

2008 GS3 is Aten-type Near Earth Asteroid that has been discovered by the Lincoln Laboratory ETS Sky Survey (MPC #704) on 2008, April 7.30; we performed its follow-up from the Remanzacco Observatory on 2008, April 7.9, while it was labeled as "BJ81650" in the NEO-CP webpage. At the beginning, it didn't show up in stackings, very likely because of the uncertainty of its ephemerids (the stacking we did was performed according the "best guess" preliminary speed and PA available at the moment).

On 2008 April 9.5, the object was still listed in the NEO-CP, but its ephemerids were considerably improved due to the follow-up astrometry produced by several observers. Then we re-stacked our original frames of the 7-8 April night with the new speed and PA, and we find it!

According to the preliminary orbital elements available at Minor Planet Center database, 2008 GS3 is a rock with an estimated diameter of nearly 100 meters, orbiting the Sun every 9.5 months. At perihelion it reaches at almost 80 Million Km from our star, between the orbits of Mercury and Venus, while at aphelion it approaches the Earth's orbit. When we imaged it, the asteroid was at 25 Million Km from our planet, moving at nearly 7.3 arcsec/min in Virgo, with a magnitude of nearly R~19.

Giovanni Sostero & Ernesto Guido