Friday, October 24, 2014

Close Approach of Asteroid 2014 SC324

The asteroid 2014 SC324 was discovered (at ~ magnitude +21.4) on 2014, September 30.2 by Mt. Lemmon Survey (MPC code G96) with a 1.5-m reflector + CCD. 

2014 SC324 has an estimated size of 40 m - 90 m (based on the object's absolute magnitude H=24.1) and it will have a close approach with Earth at about 1.5 LD (Lunar Distances = ~384,000 kilometers) or 0.0038 AU (1 AU = ~150 million kilometers) at 1921 UT on 2014, October 24. This asteroid will reach the peak magnitude about +13.6 at close approach.

We performed some follow-up measurements of this object on 2014, October 24.3 remotely from the H06 iTelescope network (New Mexico, Mayhill) through a 0.25-m f/3.4 astrograph + CCD and a 0.1-m f/5.0 astrograph + CCD. Below you can see our image taken with the asteroid at about magnitude +13.6 and moving at ~ 135 "/min (the asteroid is trailed in the image due to its fast speed). At the moment of its close approach on Oct 24 at 1921 UT, 2014 SC324 will move at ~ 221 "/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 2014 SC324 (five consecutive 60-second exposure). Click here or on the thumbnail below to see the animation (North is up, East is to the left):

Animation of asteroid 2014 SC324 - 24 October 2014 photo animation_zpssn2djfdx.gif

by Ernesto Guido, Nick Howes & Martino Nicolini

Comet C/2013 A1 & Mars - Images & Results

Comet C/2013 A1 (Siding Spring) was discovered by Australian observer R. H. McNaught with the 0.5-m Uppsala Schmidt telescope on 2013, Jan. 03 (discovery magnitude +18.6).  After its discovery, due to the uncertainty within the orbital calculations, there was thought to be a chance of a collision with Mars, but this possibility was excluded when its orbit was determined more accurately. Instead C/2013 A1 passed the planet Mars very closely on 2014, 19 October at 18:29UT. According to JPL website (With an observation arc of 733 days) the comet passed at a Nominal Distance of about 139,500 kilometers or 0.00094 AU (1 AU = ~150 million kilometers) from the Red Planet, that's closer than any previous known comet flyby of Earth or Mars. 

You can read more info about this comet and its discovery circumstances on our previous post dated back to 2013, March 04.

Astronomers, amateur astronomers and NASA's fleet of orbiters and rovers at Mars were all ready to observe this event. Below you can see a short selection of some of the most significant/preliminary results and images obtained from the observation of this flyby. Click on each image for a bigger version.


Below a wide-field image obtained by N. Howes & R. Wodaski taken few hours before the close passage on October 19.

Image credit: Nick Howes and Ron Wodaski - Tzec Maun Foundation

"Researchers used the panoramic camera (Pancam) on NASA's Mars Exploration Rover Opportunity to capture this view of comet C/2013 A1 Siding Spring as it passed near Mars on Oct. 19, 2014. This image is from a 50-second exposure taken about two-and-a-half hours before the closest approach of the comet's nucleus to Mars. The sky was still relatively dark, before Martian dawn. At the time of closest approach, the morning sky was too bright for observation of the comet. A Martian dust storm to the west of Opportunity hampered visibility somewhat on Oct. 19, compared to the sky over Opportunity a week earlier." - For more info about Opportunity's image click here.

Image Credit: NASA/JPL-Caltech/Cornell Univ./ASU/TAMU

"These images were taken of comet C/2013 A1 Siding Spring by NASA's Mars Reconnaissance Orbiter on Oct. 19, 2014, during the comet's close flyby of Mars and the spacecraft. Comet Siding Spring is on its first trip this close to the sun from the Oort Cloud at the outer fringe of the solar system. This is the first resolved imaging of the nucleus of a long-period comet. The High Resolution Imaging Science Experiment (HiRISE) camera on Mars Reconnaissance Orbiter acquired images of this comet from a minimum distance of about 86,000 miles (138,000 kilometers), yielding a scale of about 150 yards (138 meters) per pixel. Telescopic observers had modeled the size of the nucleus as about half a mile, or one kilometer, wide. However, the best HiRISE images show only two to three pixels across the brightest feature, probably the nucleus, suggesting a size less than half that estimate." - For more info about HiRISE's image click here.

Image credit: NASA/JPL/University of Arizona

"NASA's Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft obtained this ultraviolet image of hydrogen surrounding comet C/2013 A1 Siding Spring on Oct. 17, 2014, two days before the comet's closest approach to Mars. The Imaging Ultraviolet Spectrograph (IUVS) instrument imaged the comet at a distance of 5.3 million miles (8.5 million kilometers).The image shows sunlight that has been scattered by atomic hydrogen, shown as blue in this false-color representation. Comets are surrounded by a huge cloud of atomic hydrogen because water (H2O) vaporizes from the icy nucleus, and solar ultraviolet light breaks it apart into hydrogen and oxygen. Hydrogen atoms scatter solar ultraviolet light, and it was this light that was imaged by the IUVS. Two observations were combined to create this image, after removing the foreground signal that results from sunlight being scattered from hydrogen surrounding Mars." - For more info about MAVEN's image click here.


Image credit: NASA/Laboratory for Atmospheric and Space Physics/Univ. of Colorado

All other results and news about this event will be posted here as soon as they are available!

by Ernesto Guido

Monday, October 13, 2014

New fragmentation event in C/2011 J2 (LINEAR)

Starting from 2014, Sept 26.9 we are constantly monitoring comet C/2011 J2 (LINEAR) and his fragment B through a 2.0-m f/10.0 Ritchey-Chretien + CCD (La Palma-Liverpool Telescope). The video below shows an animation we made using our recent obs of this comet. Time span is 9 days (from 1 Oct. to 9 Oct). The projected velocity of the fragment is of about 0.3 arcsec/day.



While performing follow-up of component B of comet C/2011 J2 on 2014, Oct 09.9  we detected a possible new diffuse fragment located in the very near proximity of main component A. Nothing was visible on our images taken on Oct. 07.9. Below you can see our Oct. 09.9 image of the new fragment (division by azimutal median filter applied). Click here or on the image below for a bigger version.


We imaged again C/2011 J2 on Oct. 11.9 with the same setup and we confirmed the presence of a new fragment located 1.5" in PA 59 from the main component A. Below you can see our Oct. 11.9 image of the new fragment (stack of 10x20sec raw images, no filters applied). Click here or on the image below for a bigger version. 


While the new fragment is already visible in the raw images, it is even more clearly highlighted by using an appropriate filter. So below you can see the same image as above with a division by azimutal median filter applied. Click here & here or on the images below for a bigger version.


This filter creates an artificial coma, based on the photometry of the original image, and divide the original image itself in order to highlight the internal zones of different brightness that  are very close to the inner core and that would normally be hidden from the diffuse glow of the comet. Precise astrometry/photometry is difficult to obtain due to the extreme proximity and diffuse appearance of new fragment to main component A. New fragment on 2014, Oct 11.9 is definitely brighter than fragment B.

by Ernesto Guido, Nick Howes & Martino Nicolini

Wednesday, October 1, 2014

Follow-up of splitting event in Comet C/2011 J2

CBET 3979, issued on 2014 September 19, announced that observations of comet C/2011 J2 (LINEAR) (by F. Manzini, V. Oldani, A. Dan and R. Behrend) on Aug. 27.95, 28.85, and 30.91 UT led to the detection of a second, fainter, nuclear condensation (from now on Component B) located 0".8 east and 7".5 north of the main, brighter nuclear condensation (component A).

For more info about comet C/2011 J2 please see our May 2011 post on this blog by clicking here.

Whilst working on a long term morphology study on comet C/2012 K1 with N. Samarasinha and B. Mueller using the 2-meter Liverpool Telescope, we were alerted of the fragmentation event in comet C/2011 J2 and so diverted the telescope to this comet for a few days.

Our follow-up images were taken on 2014, Sept 26.9 through a 2.0-m f/10.0 Ritchey-Chretien + CCD (La Palma-Liverpool Telescope). Stacking of 10 SDSS-R filtered exposures, 20-sec each, shows component B at 14" away in PA 17 from component A. Magnitude of component B is about R = 19.5

Below you can see our follow-up image that clearly shows comet C/2011 J2 (LINEAR) and its seconday B component. Click on it for a bigger version.




For some examples of past comet fragmentation events please check the following links:


UPDATE - October 05, 2014

In the video below we show a first attempt to measure component B drifting movement from the nucleus of comet C/2011 J2 on 2014, through a 2.0-m f/10.0 Ritchey-Chretien + CCD (La Palma-Liverpool Telescope). Blinking the frames of Sept. 26.9 and Oct 02.9, there is evidence of fragment B moving off from the main comet component while profile graphs show that fragment is fading and less condensed. On Sept 26.9 the distance is of 14.4 arcsec. whilst on Oct. 2.9 the distance from the nucleus is of 15.6 arcsec. Click here to see a bigger version of the video.



by Ernesto Guido, Nick Howes & Martino Nicolini

Friday, September 5, 2014

Close Approach of Asteroid 2014 RC

The asteroid 2014 RC was discovered (at ~ magnitude +20.0) on 2014, September 01.2 by Catalina Sky Survey (MPC code 703) with a 0.68-m Schmidt + CCD (and independently detected the next night by the Pan-STARRS survey).

2014 RC has an estimated size of 12 m - 26 m (based on the object's absolute magnitude H=26.8) 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) at 1801 UT on 2014, September 07. This asteroid will reach the peak magnitude about +11.5 on Sep 7 between 17UT and 18UT.

We performed some follow-up measurements of this object on 2014, September 05.3, remotely from the U69 iTelescope network (Auberry California, USA) through a 0.61-m f/6.5 astrograph + CCD). Below you can see our image taken with the asteroid at about magnitude +17.4 and moving at ~ 1.71 "/min. At the moment of its close approach on Sep 7, around 18UT, 2014 RC will move at ~ 3300 "/min. Click on the image below to see a bigger version. North is up, East is to the left.


The graphic below depicts the passage of asteroid 2014 RC past Earth on September 7, 2014. At time of closest approach, the space rock will be about one-tenth the distance from Earth to the moon. Times indicated on the graphic are Universal Time.

Image credit: NASA/JPL-Caltech

UPDATE - September 07, 2014

Image of asteroid 2014 RC on Sep 07 at 17:30UT,  about 30 minutes before its close approach. The asteroid was at magnitude +11.2 and moving at 2971 "/min (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, Nick Howes & Martino Nicolini

Monday, August 25, 2014

New Comet: C/2014 Q3 (BORISOV)

Cbet nr. 3936, issued on 2014, August 24, announces the discovery of a comet (magnitude ~17) by G. Borisov (Observatory MARGO, Nauchnij) on CCD images obtained with a 0.3-m f/1.5 astrograph telescope on 2014, August 22.02. The new comet has been designated C/2014 Q3 (BORISOV).

We performed follow-up measurements of this object, while it was still on the neocp. Stacking of 10 unfiltered exposures, 60-sec each, obtained remotely on 2014, August 23.4 from H06 (iTelescope network - Mayhill) through a 0.50-m f/6.8 astrograph + CCD + f/4.5 focal reducer, shows that this object is a comet: coma about 7" in diameter elongated toward PA 215 (the comet was about +21 degree above the horizon at the moment of the imaging session).

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


M.P.E.C. 2014-Q38 assigns the following parabolic orbital elements to comet C/2014 Q3: T 2014 Nov. 19.24; e= 1.0; Peri. = 48.40; q = 1.63;  Incl.= 90.49

This is the third comet discovered by Gennady Borisov (previous were C/2013 N4 & C/2013 V2).

by Ernesto Guido, Nick Howes & Martino Nicolini

Wednesday, August 6, 2014

Rosetta has arrived at comet 67P!

After an epic 10-year journey, the European Space Agency’s Rosetta spacecraft arrived today August 06, 2014 at comet 67P/Churyumov–Gerasimenko becoming the first spacecraft to rendezvous with a comet.  Launched in March 2004, Rosetta had to make three gravity-assist flybys of Earth and one of Mars to help it on course to its rendezvous with the comet. This complex course also allowed Rosetta to pass by asteroids ┼áteins and Lutetia, obtaining unprecedented views and scientific data on these two objects. 

Rosetta woke up from deep space hibernation on 20 January 2014, nine million kilometres from comet 67P/Churyumov–Gerasimenko. Following wake-up, the orbiter’s 11 science instruments and 10 lander instruments were reactivated for science observations. Ten orbital correction manoeuvres were carried out between 7 May and 6 August, reducing the spacecraft’s velocity with respect to the comet from 775 m/s to 1 m/s, equivalent to walking pace. All this in preparation for the first landing on a comet expected on November.

Below you can see a high resolution (5.3 meters per pixel) image of comet Churyumov-Gerasimenko taken by OSIRIS/ROSETTA on August 3, 2014 (so 3 days before entering orbit) from a distance of 285 kilometers. Click on the image for a bigger version.


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

Below here's another image , showing the "other" side of the comet 67P. The two images are separated by about 4 hours (120 degree comet rotation). Click on the image for a bigger version.


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

Comet 67P/Churyumov-Gerasimenko activity on 2 August 2014. The image below was taken by Rosetta’s OSIRIS wide-angle camera from a distance of 550 km. The exposure time of the image was 330 seconds and the comet nucleus is saturated to bring out the detail of the comet activity. Note there is a ghost image to the right. The image resolution is 55 metres per pixel. Click on the image for a bigger version.

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

The animation below comprises 101 images acquired by the Navigation Camera on board ESA's Rosetta spacecraft as it approached comet 67P/C-G in August 2014. The first image was taken on 1 August at 11:07 UTC (12:07 CEST), at a distance of 832 km. The last image was taken 6 August at 06:07 UTC (08:07 CEST) at a distance of 110 km. Click here or on the thumbnail before for a bigger version.

 Navigation Camera on board ESA's Rosetta spacecraft as it approached comet 67P/C-G in August 2014 photo NavCam_animation_6_August_node_full_image_2_zpsd78d86fd.gif


According to the official ESA press release
Comet 67P/Churyumov–Gerasimenko and Rosetta now lie 405 million kilometres from Earth, about half way between the orbits of Jupiter and Mars, rushing towards the inner Solar System at nearly 55 000 kilometres per hour.  Today, Rosetta is just 100 km from the comet’s surface, but it will edge closer still. Over the next six weeks, it will describe two triangular-shaped trajectories in front of the comet, first at a distance of 100 km and then at 50 km. At the same time, more of the suite of instruments will provide a detailed scientific study of the comet, scrutinising the surface for a target site for the Philae lander. Eventually, Rosetta will attempt a close, near-circular orbit at 30 km and, depending on the activity of the comet, perhaps come even closer. As many as five possible landing sites will be identified by late August, before the primary site is identified in mid-September. The final timeline for the sequence of events for deploying Philae – currently expected for 11 November – will be confirmed by the middle of October. After landing, Rosetta will continue to accompany the comet until its closest approach to the Sun in August 2015 and beyond, watching its behaviour from close quarters to give us a unique insight and realtime experience of how a comet works as it hurtles around the Sun


In November 2014, a small lander (named Philae) will leave the spacecraft and will harpoon itself to the surface of the comet 67P.



Below you can find an image of comet 67P taken by our team (Nick Howes, Giovanni Sostero, Alison Tripp and Ernesto Guido) on 25 April 2012, when comet was at roughly 5.683 AU from the Sun (so close to its aphelion) and of magnitude ~22. For more info on that imaging session and also for our image of this comet dated back to 2010 click here & here.


This blog will be updated as soon as new images and news will arrive so stay tuned!


UPDATE - August 06, 2014 @13:00UT

Stunning close up detail focusing on a smooth region on the ‘base’ of the ‘body’ section of comet 67P/Churyumov-Gerasimenko. The image was taken by Rosetta’s OSIRIS narrow-angle camera and downloaded today, 6 August. The image clearly shows a range of features, including boulders, craters and steep cliffs. The image was taken from a distance of 130 km and the image resolution is 2.4 metres per pixel. Click on the image for a bigger version.


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

While below there is a close-up detail of comet 67P/Churyumov-Gerasimenko. The image was taken by Rosetta’s OSIRIS narrow-angle camera and downloaded today, 6 August. The image shows the comet’s ‘head’ at the left of the frame, which is casting shadow onto the ‘neck’ and ‘body’ to the right. The image was taken from a distance of 120 km and the image resolution is 2.2 metres per pixel. Click on the image for a bigger version.


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

UPDATE - August 06, 2014 @18:00UT

The View From Rosetta - Animation of comet 67P recorded by Rosetta's navigational camera. (Credit: European Space Agency/BBC News). Click here or on the thumbnail below for a bigger version.

Comet 67P - Credit: European Space Agency/BBC News photo rosetta-comet-67p-orbit-525_zpsc9ba2c58.gif

UPDATE - August 08, 2014 @16:00UT

Full-frame NAVCAM image taken on 5 August 2014 from a distance of about 145 km from comet 67P/Churyumov-Gerasimenko. Click on the image for a bigger version.

Credits: ESA/Rosetta/NAVCAM

Full-frame NAVCAM image taken on 7 August 2014 from a distance of about 83 km from comet 67P/Churyumov-Gerasimenko. Click on the image for a bigger version.

Credits: ESA/Rosetta/NAVCAM

An extract from the last post on Rosetta blog:

"Now that comet 67P/Churyumov-Gerasimernko is within our reach, Rosetta’s mass spectrometer COSIMA, managed by the Max Planck Institute for Solar System Research in Germany, is beginning to reach for cometary dust. Literally. On Sunday 10 August 2014, COSIMA will expose its first of 24 targetholders aiming to collect single dust particles. This might take a while. After all, from dust particle modeling, 67P/C-G’s coma is still comparable to a high-quality cleanroom. But, as 67P/C-G travels closer to the Sun along its orbit, the comet’s activity will increase and more dust will be within reach. For now, we are planning to keep the target exposed for one month, but checking on a weekly basis if the model predictions are not too low and if we are lucky."

UPDATE - August 23, 2014

The image below shows Comet 67P/Churyumov-Gerasimenko imaged by Rosetta's OSIRIS narrow angle camera on 7 August from a distance of 104 km. "While the comet’s head (in the top half of the image) is covered with parallel linear features, the neck displays scattered boulders on a smooth underground. In comparison, the comet’s body (lower half of the image) seems to have much more jagged features.". Click on the image for a bigger version.

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

A 2 day meeting started today at @CNES_France where scientists and engineers (the Landing Site Selection Group (LSSG)) will select 5 possible landing sites for Philae that will be announced on Monday. Final decision will be confirmed by the middle of October. To see how many factors influence the decision for the landing site see this blog post on Rosetta website.

According to Rosetta blog: "The Global Mapping phase runs 10 September to 7 October, and will see Rosetta going down to just 29 km distance, a point when we expect the spacecraft to become actively captured by the comet’s gravity, and its orbit to become circular. The aim is to get down to 19km height, keeping Rosetta on the Sunlit side or orbiting on the terminator line."

Below you can see the most recent image released by Rosetta taken by its navigation camera (NAVCAM) on 22 August 2014 at a distance of about 64 km from comet 67P. Click on the image for a bigger version.

Credits: ESA/Rosetta/NAVCAM


Below a Rosetta-67P related cartoon by Stephen Collins for the The Guardian . Click on the image for a bigger version.

Credits: Stephen Collins


UPDATE - September 30, 2014

Below you can find a summary of latest news about Rosetta mission. (Click on each image for a bigger version.)

- Site J marks the spot where @Philae2014 will land on comet 67P. Full story on Rosetta blog here.


- Amazing comet 67P image taken by @ESA_Rosetta NAVCAM on 19 Sep 2014 from 28.6 km with jets emanating from the neck region 


- New comet #67P four-image mosaic by @ESA_Rosetta NAVCAM taken on 24 Sept 2014 from 28.5 km + + zoom on large boulders (several metres across) lying in the smooth ‘neck’ region



-  The date is set! @Philae2014 will land on comet 67P on 12 November 2014

by Ernesto Guido