Wednesday, October 8, 2008

2008 TC3 Update - Impact Flash Imaged from Satellite

Impact Flash Imaged from Satellite

While ground pictures of the fireball are still missing (the event occurred in a remote area over northern Sudan), it looks like finally there is an image of the impact flash.

The explosion was imaged by the weather satellite Meteosat 8.

The image is available at SpaceWeather.com: http://tinyurl.com/3r2ool



According to J. Borovicka, Astronomical Institute, Czech Academy of Sciences, the bright spot on the images taken by the weather satellite Meteosat 8 has been noticed by Z. Charvat. This bright spot likely corresponds to the atmospheric entry of 2008 TC_3 over northern Sudan (see - IAU Circular No. 8994).


Impactor 2008 TC3 entering Earth' shadow

Roughly one hour before expected atmospheric impact over northern Sudan, 2008 TC3 entered Earth' shadow becoming invisible until the impact.

The entry in the Earth' shadow has been imaged by La Sagra Sky Survey, Spain. Their nice image is here:



This image also shows a periodic light variation along the trail that indicates a fast rotation. The same effect is evident in the image obtained by italian astronomer Walter Boschin at the 3.58m diameter Telescopio Nazionale Galileo (TNG):


by Ernesto Guido

Tuesday, October 7, 2008

2008 TC3 Animation

Animation showing the motion of small asteroid 2008 TC3 few hours before entering Earth atmosphere. 

Images obtained at Remanzacco Observatory by G. Sostero, E. Guido & P. Camilleri.



video

Same animation on Youtube:

http://tinyurl.com/4o5o2u

by Ernesto Guido

Small Asteroid 2008 TC3 to hit Earth Tonight

On the morning of 06 October 2008, astronomer R. Kowalsky of Mount Lemmon Survey detected a small object (absolute magnitude H=30.4) now designated 2008 TC3.

According to NeoDys and Jpl Neo experts, the impact with the Earth atmosfere is almost certain and it should be at 0246 UTC of 07 October 2008. Fortunately this object is only a small chunk of rock few meters in size and should not survive passage through the atmosphere. In case some fragments should reach the ground, the impact zone has been located in the northern Sudan.

No damage is expected.

The entry in the atmosphere should be visible over northern Africa and possibly even over southern Europe.

Almost certainly 2008 TC3 will be the first impacting object discovered before entry into the Earth's atmosphere.

Here you can see our follow-up images of 2008 TC3 taken few hours before its entry in Earth's atmosphere  (click on the image for a bigger version):

The discovery mpec:
http://www.cfa.harvard.edu/mpec/K08/K08T50.html

By G. Sostero, E. Guido and P. Camilleri

Friday, October 3, 2008

COMET P/2008 T1 (BOATTINI)

IAUC nr. 8988, published on 2008, Oct. 2, announces the discovery of another comet (his fifth) by Andrea Boattini, named P/2008 T1 (BOATTINI). This 18.th magnitude object has been found in Pisces, during the Catalina Sky Survey search, with a 1.5-m reflector. The discoverer reported a fairly condesed coma about 10-arcsec in diameter, and a fan-shaped tail nearly 1 arcmin long, in PA ranging 245-275 deg. After its posting on the Minor Planet Center's NEO-Confirmation Page, several observers confirmed its cometary nature, remarking the presence of the above mentioned broad fan tail toward West-Southwest. We imaged it remptely from Mayhill (NM) through a 0.25-m, f/3.4 reflector + CCD around Sept. 2.4 (details on image):

http://tinyurl.com/3fkg5u

Preliminary orbital elements published by the Minor Planet Center on M.P.E.C. 2008-T30:

http://www.cfa.harvard.edu/mpec/K08/K08T30.html

provides a solution that points toward a "Jupiter family" object, with perihelion on February 2008 (e=0.29, q~ 3.02 AU, i~ 2.1 deg). Under these circumstances, it appears that this comet has experienced a close encounter with Jupiter around June 2002.In the next future, P/2008 T1 will gradually decrease its brightness, staying not far from the ecliptic for several months to came.

Updated ephemerids are available at the MPC webpage:

http://www.cfa.harvard.edu/iau/Ephemerides/Comets/2008T1.html

by Ernesto Guido, Giovanni Sostero and Paul Camilleri

Wednesday, October 1, 2008

COMET C/2008 S3 (BOATTINI)

IAUC nr. 8986, published on 2008, Sept.30, announces the discovery of a comet by Andrea Boattini, named C/2008 S3 (BOATTINI). It has been found in Taurus, during the Catalina Sky Survey search, with a 1.5-m reflector. The discoverer reported a coma having a strong condensation and a coma about 10-arcsec in diameter, elongated toward PA 115-deg, with total magnitude about 18.5. After its posting on the Minor Planet Center's NEO-Confirmation Page, several observers confirmed its cometary nature.

We imaged it remptely from Mayhill (NM) through a 0.25-m, f/3.4 reflector + CCD around Sept. 30.4 (details on image):

http://tinyurl.com/3s6adt

Preliminary orbital elements published by the Minor Planet Center on M.P.E.C. 2008-S96 (http://www.cfa.harvard.edu/mpec/K08/K08S96.html) assume a parabolic retrograde orbit with perihelion on April 2011 (e=1, q~ 3.1 AU, i~ 158 deg). It's noteworthy the fact that the comet has been discovered to be active at about 8.3 AU from the Sun; this seems to indicate a rather "alive" object also at relatively high distances from our star.

Maxim brightness is supposed to be reached in the Summer of 2011, at about magnitude 12 (well placed in the sky for both hemispheres); obviously all the previous extrapolations are based on measurements conducted upon a very short arc of orbit, so they must be confirmed by further astrometric and photometric follow-up.

Updated ephemerids are available at the MPC webpage:

http://www.cfa.harvard.edu/iau/Ephemerides/Comets/2008S3.html

by Ernesto Guido, Giovanni Sostero and Paul Camilleri

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):

http://tinyurl.com/46ttlx

By Ernesto Guido & Giovanni Sostero

(1) http://echo.jpl.nasa.gov/asteroids/2008QS11/2008QS11_planning.html