Tuesday, December 8, 2015

New Comet: C/2015 X4 (ELENIN)

CBET nr. 4216, issued on 2015, December 08, announces the discovery of a comet (magnitude ~18.2) by L. Elenin on three CCD images obtained with a 0.4-m f/3 reflector at the ISON-NM observatory near Mayhill, NM, USA on Dec. 3.5 UT. The new comet has been designated C/2015 X4 (ELENIN)

I performed follow-up measurements of this object, while it was still on the neocp. Stacking of 20 unfiltered exposures, 120 seconds each, obtained remotely on 2015, December 03.9 from I89 (iTelescope network - Nerpio) through a 0.32-m f/8.0 astrograph + CCD, shows that this object is a comet with a compact coma nearly 8 arcsec in diameter elongated toward PA 290.

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



M.P.E.C. 2015-X105 assigns the following preliminary elliptical orbital elements to comet C/2015 X4: T 2015 Nov. 2.64; e= 0.81; Peri. =  176.15; q = 3.39;  Incl.= 29.49


by Ernesto Guido

Thursday, November 12, 2015

WT1190F to hit Earth's atmosphere on Nov. 13, 2015

An object (probably space junk) discovered on October 3, 2015 by the Catalina Sky Survey and designated WT1190F will enter the Earth's atmosphere on 13 November 2015, making it one of the very few space impacting object observed prior to atmospheric entry (see old posts about asteroids 2008 TC3 & 2014 AA).  

This object will re-enter Earth's atmosphere in a few hours, around 06:20 UT on 13 November 2015 about 100 km off the southern coast of Sri Lanka (at 11:50am local time). It is quite small, probably about one or two meters across and so it is expected that most or all of WT1190F will burn up in the atmosphere before impacting, but will be possibly visible as a bright daytime fireball. 

Click on the images below to see the impact location. The magenta blob off the south coast of Sri Lanka is the nominally predicted impact area. According to Bill Gray: "nominally predicted impact area is the area within which we'd expect it to hit, assuming the object doesn't move in unexpected ways. Small objects such as this are pushed around a bit by sunlight. So I won't be surprised if it lands a couple of kilometers outside the predicted region". 


Credit: Bill Gray


Credit: Bill Gray


After collecting more observations and unearthing 2012 and 2013 obs from telescope archives, it has been possible to conclude that WT1190F is most probably a piece of discarded space junk. In fact WT1190 interacts with solar radiation pressure in a way that suggests it has low density (space junk is a lot lighter than a rock. It's so light that even sunlight can exert a very gentle push on it). Moreover it is in a very unusual and elongated orbit (eccentricity 0.96) taking it to within one Earth radius of the surface of the Earth at perigee but 1.65 Lunar Distances at apogee. It could be a spent rocket stage or panelling shed by a recent Moon mission. It is also possible that the debris dates back decades, perhaps even to the Apollo era.  Below a plot of the last three orbits of WT1190F. The small red circle is the earth. The big green circle is the orbit of the moon, just to give some scale to the chart (click on it for a bigger version).

Credit: Bill Gray


For more detailed info about the nature, size & history of this object please check the webpage maintained by Bill Gray at Project Pluto.

Astrometry obtained just before impact will help to pin down the trajectory and the impact location. So, I performed follow-up measurements of this object, about 22 hours before it entering Earth's atmosphere. Below you can see the image showing WT1190F at magnitude ~18.5, stacking of 30 unfiltered exposures, 30-sec each, obtained remotely on 2015, November 12.4 from H06 (iTelescope network - New Mexico) through a 0.43-m f/6.8 astrograph + CCD + f/4.5 focal reducer. Click on the image below for a bigger version. 




Below a short animation (spanning about 10 minutes) made out of my follow-up images. The first frame was obtained at 08:17UT while the second frame was obtained at 08:27UT of Nov, 12, 2015. (WT1190F is the star-like object at the centre while stars are trailed because the images were stacked on WT1190F motion)




UPDATE - November 13, 2015

First images of WT1190F reentry are available!! Images obtained by a team of researchers under the consortium "Rapid Response to a next TC3 asteroid impact". They were observing the event from an airborne sponsored by United Arab Emirates Space Agency & the International Astronomical Center (IAC) in Abu Dhabi.

Credit: IAC/UAE/NASA/ESA

Credit: IAC/UAE/NASA/ESA

Credit: IAC/UAE/NASA/ESA

Credit: IAC/UAE/NASA/ESA

See also the video below prepared by the expedition team, with photos of the re-entry and  of the cameras & instruments used on the airborne to follow the event: 



by Ernesto Guido

Thursday, November 5, 2015

New Comet: C/2015 V2 (JOHNSON)

CBET nr. 4161, issued on 2015, November 05, announces the discovery of a comet (magnitude ~17.1) by J. A. Johnson on CCD images obtained with the Catalina Sky Survey's 0.68-m Schmidt telescope on Nov. 3.5 UT. The new comet has been designated C/2015 V2 (JOHNSON).

I performed follow-up measurements of this object, while it was still on the neocp. Stacking of 12 unfiltered exposures, 120 seconds each, obtained remotely on 2015, November 04.4 from H06 (iTelescope network - New Mexico) through a 0.43-m f/6.8 astrograph + CCD + f/4.5 focal reducer, shows that this object is a comet: compact coma nearly 10 arcsec in diameter elongated toward PA 230.

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



M.P.E.C. 2015-V44 assigns the following preliminary parabolic orbital elements to comet C/2015 V2: T 2017 Feb. 14.70; e= 1.0; Peri. =  188.19; q = 0.93;  Incl.= 41.14

Below you can see a graph generated using the software Orbitas and showing the C/2015 V2 predicted magnitude (in red) versus its elongation from the Sun. Click on the image for a bigger version. (A word of caution: as always with comets, the future magnitudes reported here are only indicative and based on a very preliminary orbit).




by Ernesto Guido

Monday, October 26, 2015

Close Approach of Asteroid 2015 TB145

The asteroid 2015 TB145 was discovered  (at ~ magnitude +20) on 2015, October 10 by  Pan-STARRS I survey (MPC code F51) with a 1.8-m Ritchey-Chretien + CCD. 

Asteroid 2015 TB145 has an estimated size of 290 m - 650 m (based on the object's absolute magnitude H=19.8) and it will have a close approach with Earth at about 1.3 LD (Lunar Distances = ~384,000 kilometers) or 0.0033 AU (1 AU = ~150 million kilometers) on 2015, October 31 at 17:01UT. This asteroid will reach the peak magnitude about +10 between on October 31. Radio astronomers will try to  observe it as the radar signal-to-noise ratios will be very strong "so this should be one of the best radar targets of the year.  We hope to obtain images with a range resolution as high as 2 m/pixel using DSS-13 to transmit and Green Bank (and possibly Arecibo) to receive. The flyby presents a truly outstanding scientific opportunity to study the physical properties of this object."

Moreover 2015 TB145 is in an extremely eccentric (~0.86) and high inclination (~40 deg) orbit.  It has a Tisserand parameter of 2.937 hinting that it may be cometary in nature. If so, then this would be the first time that the Goldstone radar has imaged a comet from such a close distance. The encounter velocity is 35 km/s, which is unusually high.  

The graphic below depicts the orbit of asteroid 2015 TB145 (click on the image for a bigger version). 

Credit: (NASA/JPL - Caltech)

The graphic below depicts the passage of asteroid 2015 TB145 past Earth on October 31, 2015 (click on the image for a bigger version). 

Credit: P. Chodas (NASA/JPL - Caltech)


This flyby of 2015 TB145 will be the closest by any known space rock this large until asteroid (137108) 1999 AN10 (absolute magnitude H=17.9) flies past Earth in 2027 within one lunar distance. On April 2017, another asteroid "2014 JO25" (absolute magnitude H=18.1) will pass at about 4.8 LD from Earth. 


I performed some follow-up measurements of this object on 2015, October 26.5, remotely from the Q62 iTelescope network (Siding Spring, Australia) through a 0.50-m f/6.8 astrograph + CCD + focal reducer). Below you can see our image taken with the asteroid at about magnitude +16 and moving at ~ 0.78 "/min (full moon was only 48 degree away from the asteroid). At the moment of its close approach on Oct 31, around 17UT, 2015 TB145 will move at ~ 880 "/min (or about  14.7 deg/hour). Click on the image below to see a bigger version. (North is up, East is to the left).



The chart below shows the path of asteroid 2015 TB145 as it sweeps past Earth at 35 km per second. "During this 20-hour-long period the asteroid's magnitude varies from 10.1 to 12.2, and its proximity to Earth will create a parallax shift of ½° or more. So you won't be able to point your telescope based on this track; instead, you will need to consult another source (for example the MPC website) to generate positions specific to your location" (click on the image for a bigger version). 



UPDATE - November 02, 2015

The radar images from Arecibo indicate the object is spherical in shape and approximately 600 meters (2,000 feet) in diameter and completes a rotation about once every five hours.


Credits: NAIC-Arecibo/NSF

The animated GIF above was generated using radar data collected by the National Science Foundation's 305-meter (1,000-foot) Arecibo Observatory in Puerto Rico. The six radar images used in the animation were taken on Oct. 30, 2015, and the image resolution is 7.5 meters (25 feet) per pixel.

Radar images obtained at the Arecibo Observatory appear to rotate clockwise, which is noticeable by the movement of bright features. “The bright and dark features are indication of surface irregularities. For example, the central dark feature may be a large circular depression, possibly an impact crater”, commented Dr. James Richardson, USRA Scientist in the Planetary Radar Group. 

Scientists observing asteroid 2015 TB145 with NASA's Infrared Telescope Facility (IRTF) on Mauna Kea, Hawaii, have determined that the celestial object is more than likely a dead comet that has shed its volatiles after numerous passes around the sun. Indeed researchers now estimate that its surface reflects only about 6% of the sunlight that strikes it (most comets have a reflectivity in the range of 3% to 5%, but asteroids are usually considerably higher, around 15% to 20%).

UPDATE - November 03, 2015

Below the new radar animation of asteroid 2015 TB145 obtained by the radar team of Arecibo Observatory on Nov 1, 2015.

Credits: Arecibo Obs/NASA/NSF

by Ernesto Guido

Thursday, October 1, 2015

NOVA SAGITTARII 2015 No. 3

Following the posting on the Central Bureau's Transient Object Confirmation Page about a possible Nova in Sgr (TOCP Designation: PNV J18033275-2816054) we performed some follow-up of this object remotely through a 0.43-m f/6.8 astrograph + CCD) of  iTelescope network (MPC Code  Q62 - Siding Spring).

On our images taken on September 28.4, 2015 we can confirm the presence of an optical counterpart with R-CCD magnitude 9.5 at coordinates:

R.A. = 18 03 32.77, Decl.= -28 16 05.3

(equinox 2000.0; UCAC4 catalogue reference stars).

Our annotated confirmation image. Click on it for a bigger version:
 
 
An animation showing a comparison between my confirmation image and the archive POSS1 Blue plate (1958-04-18). Click here or on the thumbnail below for a bigger version:

PNV J18033275-2816054 photo PNV_Sgr - T17 Q62 - 28 Settembre 2015_zps44qnohhw.gif

According to CBET nr. 4145, issued on 2015, September 30, , PNV J18033275-2816054 is now NOVA SAGITTARII 2015 No. 3. This nova has been discovered K. Itagaki (Teppo-cho,Yamagata, Japan) on an unfiltered CCD frame taken on Sept. 27.429 UT using a 180-mm-focal-length camera lens.

A spectrogram (resolution about 500 at H-beta) taken of PNV J18033275-2816054 by M. Fujii (Kurashiki, Okayama, Japan) with a 0.4-m telescope on Sept. 27.487 UT shows Balmer emission lines, with the H-beta line having a P-Cyg profile that indicates an expansion velocity of about 1100 km/s.  Emission lines of Fe II (37), (42), and (49) also have P-Cyg profiles.  The Na D absorption is remarkable. (see image below).

Credit: M. Fujii

by Ernesto Guido

Wednesday, September 2, 2015

New Comet: P/2015 Q2 (PIMENTEL)

CBET nr. 4140, issued on 2015, September 02, announces the discovery of a comet (magnitude ~18.5) by Eduardo Pimentel on Aug. 24.2 UT with a 0.45-m f/2.9 reflector of the SONEAR Observatory at Oliveira. Follow-up observations to confirm the object were obtained by C. Jacques, E. Pimentel, and J. Barros with the same telescope on Aug. 27.3 and31.3. The new comet has been designated P/2015 Q2 (PIMENTEL).

We performed follow-up measurements of this object, while it was still on the neocp. Stacking of 30 unfiltered exposures, 30 seconds each, obtained remotely on 2015, August 31.7 from Q62 (iTelescope network - Siding Spring) through a 0.50-m f/6.8 astrograph + CCD + f/4.5 focal reducer, shows that this object is a comet with a  sharp central condensation surrounded by diffuse irregular coma 5" in diameter and a tail about 10" in PA 315

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


M.P.E.C. 2015-R02 assigns the following preliminary elliptical orbital elements to comet P/2015 Q2: T 2015 Sept. 10.23; e= 0.76; Peri. =  244.36; q = 1.82;  Incl.= 146.18


by Ernesto Guido & Nick Howes

Tuesday, August 11, 2015

New Comet: C/2015 P3 (SWAN)

CBET nr. 4136, issued on 2015, August 11, announces the discovery of a comet (magnitude ~11) by M. Mattiazzo on low-resolution public website hydrogen Lyman-alpha images obtained during Aug. 3 and 4 with the Solar Wind Anisotropies (SWAN) camera on the Solar and Heliospheric Observer (SOHO) spacecraft. The new comet has been designated C/2015 P3 (SWAN).

We performed follow-up measurements of this object, while it was still on the neocp. Stacking of 13 unfiltered exposures, 15-sec each, obtained remotely on 2015, August 10.4 from Q62 (iTelescope network - Siding Spring) through a 0.50-m f/6.8 astrograph + CCD + f/4.5 focal reducer, shows that this object is a comet: sharp central condensation surrounded by bright coma about 1 arcmin in diameter.

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


M.P.E.C. 2015-P25 assigns the following very preliminary parabolic orbital elements to comet C/2015 P3: T 2015 July 27.26; e= 1.0; Peri. =  131.81; q = 0.71;  Incl.= 59.32


by Ernesto Guido & Nick Howes

Monday, July 13, 2015

New Horizons’ Pluto flyby on 14 July

After a 9½ years journey, NASA’s New Horizons spacecraft will visit tomorrow 14 July 2015 the dwarf planet Pluto. This will be the first ever flyby of Pluto and its largest moon Charon.

During the fly-by (a 24-hour event), New Horizons will collect photographs and scientific data on Pluto’s surface, atmosphere and environment. New Horizons is intended to pass within 12,500 km (7,800 miles) of Pluto, with this closest approach date estimated to occur on July 14, 2015 at 11:50 UTC. New Horizons will have a relative velocity of 13.78 km/s (49,600 km/h; 30,800 mph) at its closest approach, and will come as close as 28,800 km (17,900 miles) to Charon.

The spacecraft will not go into orbit around Pluto because, as explained on New Horizons website, "to get to Pluto (which is 5 billion kilometers from Earth) in just 9.5 years the spacecraft travelled very, very quickly. As a result, New Horizons will speed by Pluto at a velocity of about 43,000 kilometers per hour(27,000 miles per hour). To get into orbit, operators would have to reduce that speed by over 90%, which would require more than 1,000 times the fuel that New Horizons can carry. The second reason is scientific: If we did stop to go into orbit, we wouldn't be able to go on to explore the Kuiper Belt!"

Click on the images below to see a graphical guide to the historic mission made by Nature magazine.


Below you can find a selection of the best images of Pluto & Charon taken by New Horizons during the weeks preceding the 14 July fly-by (click on each image for a bigger version).

Pluto and Charon rotation sequence. The images were taken May 28-June 3, 2015. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

Pluto as seen from New Horizons on July 07, 2015. Credit: NASA/JHUAPL/SWRI

Pluto and Charon as seen from New Horizons on July 08, 2015. Credit: NASA/JHUAPL/SWRI
 

Pluto as seen from New Horizons on July 11, 2015. Credit: NASA/JHUAPL/SWRI

Charon as seen from New Horizons on July 11, 2015. Credit: NASA/JHUAPL/SWRI

Below the fly-by animation (made by Björn Jónsson using New Horizons' data) showing the fly-by trajectory from 09:36UT to 13:36UT. Closest approach 11:50UT (Charon not included in the animation).


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


UPDATE - July 14, 2015 @10:00UT

Less than 2 hours left to the Pluto flyby by New Horizons spacecraft. Google is celebrating today historic Pluto flyby with its own Google Doodle. (click on the image below for a bigger version).


Below you can see the last and most detailed image of Pluto sent to Earth before the moment of closest approach! "This stunning image of the dwarf planet was captured from New Horizons at about 4 p.m. EDT on July 13, about 16 hours before the moment of closest approach."



UPDATE - July 15, 2015 @20:00UT

Below you can see the amazing first close-up photographs of Pluto and its largest moon Charon + an image of smaller moon Hydra sent back to the Earth by NASA’s New Horizons spacecraft a day after its successful flyby (click on each image for a bigger version).


New close-up images of a region near Pluto’s equator reveal a giant surprise -- a range of youthful mountains rising as high as 11,000 feet (3,500 meters) above the surface of the icy body. Credits: NASA/JHU APL/SwRI

Remarkable new details of Pluto’s largest moon Charon are revealed in this image. Credit: NASA-JHUAPL-SwRI

New Horizons measured the size of Hydra, one of Pluto’s small moons, which is 43km wide and 33km tall. The moon is so reflective that it is likely composed of water ice. Credit: NASA-JHUAPL-SwRIAggiungi didascalia

The latest spectra from New Horizons Ralph instrument reveal an abundance of methane ice, but with striking differences from place to place across the frozen surface of Pluto. Credit: NASA-JHUAPL-SwRI

By Ernesto Guido

Monday, June 1, 2015

Amor Asteroid (2015 KQ154)

The MPEC 2015-K126 issued on May 28, 2015 announced the discovery of a new Amor-type asteroid officially designated 2015 KQ154. This asteroid (~ magnitude 16) was discovered by C. Jacques, E. Pimentel & J. Barros through a 0.28-m f/2.2 astrograph + CCD telescope of SONEAR Observatory (MPC code Y00), on images obtained on May 25.1, 2015. 

According to the preliminay orbit, 2015 KQ154 is an Amor type asteroid. Amor asteroids are a group of Near-Earth objects with orbits similar to that of 1221 Amor (1.017 AU < q < 1.3 AU). They approach the orbit of Earth from beyond, but do not cross it. Most Amors do cross the orbit of Mars. Click on the image below to see the orbit types of the different groups of Near-Earth asteroids.


We performed some follow-up measurements of this object on 2015, May 28.4, remotely from the U69 MPC code (iTelescope network - Auberry California) through a 0.61-m f/6.5 astrograph + CCD. Below you can see an animation showing the fast movement of 2015 KQ154 on the the sky on May 28, 2015 (it was moving at 8.35 "/min). Each frame is a single 10-second exposure. Click on the thumbnail below to see the animation (East is up, North is to the right):


Animation of Asteroid 2015 KQ154 - 28 May 2015 photo 2015_KQ154_28_May_2015_U69_crop_zpsnwd0ey9t.gif

Congrats to SONEAR team for the discovery of 2015 KQ154, that is the thirteenth Near Earth Object discovered by their survey.

by Ernesto Guido & Nick Howes

Wednesday, May 27, 2015

New Comet: C/2015 K4 (PANSTARRS)

CBET nr. 4108, issued on 2015, May 27, announces the discovery of a comet (magnitude ~18) by PANSTARRS survey in three w-band exposures taken with the 1.8-m Pan-STARRS1 telescope at Haleakala on May 24.5 UT. The new comet has been designated C/2015 K4 (PANSTARRS).

We performed follow-up measurements of this object, while it was still on the neocp. Stacking of 20 unfiltered exposures, 30-sec each, obtained remotely on 2015, May 26.3 from U69 (iTelescope network - Auberry California) through a 0.61-m f/6.5 astrograph + CCD, shows that this object is a comet with a ill-defined central condensation surrounded by diffuse irregular coma about 6" in diameter

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


M.P.E.C. 2015-K114 assigns the following preliminary parabolic orbital elements to comet C/2015 K4: T 2015 May 1.79365; e= 1.0; Peri. = 357.56; q = 2.01;  Incl.= 80.25

by Ernesto Guido & Nick Howes

Friday, April 10, 2015

New Comet: C/2015 G2 (MASTER)

CBET nr. 4092, issued on 2015, April 10, announces the discovery of a comet (magnitude ~11) on R-band images taken by P. Balanutsa et al. with the MASTER (Mobile Astronomical System of the Telescope-Robots) 0.4-m f/2.5 reflector at the South African Astronomical Observatory.  The new comet has been designated C/2015 G2 (MASTER).

We performed follow-up measurements of this object, while it was still on the neocp. Stacking of 10 unfiltered exposures, 30-sec each, obtained remotely on 2015, April 08.8 from Q62 (iTelescope network - Siding Spring) through a 0.50-m f/6.8 astrograph + CCD + focal reducer, shows that this object is a comet with a very bright coma nearly 3 arcmin in diameter and a tail about 15 arcminutes long in PA 253.

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




M.P.E.C. 2015-G28 (including pre-discovery MASTER observations from Mar. 30.1 UT, showing the comet at mag 11.5-11.6) assigns the following preliminary parabolic orbital elements to comet C/2015 G2: T 2015 May 23.80; e= 1.0; Peri. = 257.48; q = 0.78;  Incl.= 147.56

Below you can see a graph generated using the software Orbitas and showing the C/2015 G2 predicted magnitude (in red) versus its elongation from the Sun. Click on the image for a bigger version.


by Ernesto Guido & Nick Howes

Tuesday, March 31, 2015

New Comet: C/2015 F4 (JACQUES)

CBET nr. 4085, issued on 2015, March 31, announces the discovery of a comet (magnitude ~16) by C. Jacques on CCD images taken on 2015, March 27.2  by C. Jacques, E. Pimentel and J. Barros with a 0.28-m f/2.2 astrograph at the SONEAR Observatory (Oliveira, Brazil).  The new comet has been designated C/2015 F4 (JACQUES).

We performed follow-up measurements of this object, while it was still on the neocp. Stacking of 14 unfiltered exposures, 60-sec each, obtained remotely on 2015, March 27.7 from Q62 (iTelescope network - Siding Spring) through a 0.43-m f/6.8 astrograph + CCD, shows that this object is a comet with a sharp central condensation surrounded by a coma about 8" in diameter and a tail about 15" long in PA 237.

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


M.P.E.C. 2015-F159 assigns the following preliminary parabolic orbital elements to comet C/2015 F4: T 2015 Aug. 8.20; e= 1.0; Peri. = 31.64; q = 1.73;  Incl.= 47.82


Below you can see the discovery images  (click on it for a bigger version)

Credit: SONEAR Observatory

by Ernesto Guido & Nick Howes

Thursday, March 26, 2015

New Comet: C/2015 F2 (POLONIA)

CBET nr. 4083, issued on 2015, March 26, announces the discovery of a comet (magnitude ~17) by R. Reszelewski, M. Kusiak, M. Gedek and M. Zolnowski on CCD images taken on 2015, March 23 with a remote-controlled 0.1-m f/5 astrograph of the Polonia Observatory at San Pedro de Atacama, Chile, in the course of their comet-search program. The new comet has been designated C/2015 F2 (POLONIA).
 
We performed follow-up measurements of this object, while it was still on the neocp. Stacking of 14 unfiltered exposures, 30 seconds each, obtained remotely on 2015, March 23.8 from Q62 (iTelescope network - Siding Spring) through a 0.43-m f/6.8 astrograph + CCD, shows that this object is a comet with ill-defined central condensation surrounded by diffuse irregular coma 15" in diameter.

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


M.P.E.C. 2015-F120 assigns the following preliminary parabolic orbital elements to comet C/2015 F2: T 2015 Apr. 28.77; e= 1.0; Peri. = 351.97; q = 1.21;  Incl.= 28.87

by Ernesto Guido & Nick Howes

Monday, March 16, 2015

Bright Nova in Sgr - (PNV J18365700-2855420)

Following the posting on the Central Bureau's Transient Object Confirmation Page about a possible bright Nova in Sgr (TOCP Designation: PNV J18365700-2855420) we performed some follow-up of this object remotely through a 0.61-m f/6.5 astrograph + CCD) of  iTelescope network (MPC Code  U69 - Auberry, California - USA).

On our images taken on March 16.5, 2015 we can confirm the presence of an optical counterpart with R-CCD magnitude 5.9 at coordinates:

R.A. = 18 36 56.85, Decl.= -28 55 40.0 (equinox 2000.0; UCAC-4 catalogue reference stars).

Our wide-Field colour image of Nova Sagittarii 2015 No. 2. Details on the caption. Click on the image for a bigger version.


Click here or on the thumbnail below to see the full wide-field frame with the nova at the center.


Our annotated confirmation image. Click on it for a bigger version.


An animation showing a comparison between our confirmation image and the archive POSS2/UKSTU plate (R Filter - 1996). Our image was obtained when the object was only about +15 degree on the horizon. Click here or on the thumbnail below for a bigger version:

Possible Nova in Sgr - 16 March 2015 photo 
PNV_SGR_16_March_Guido_U69_T24_animation_zpse5moqno2.gif

According to the Atel #7230 "an optical spectrum of PNV J18365700-2855420 (see CBAT TOCP) was obtained using the FRODOspec spectrograph on the Liverpool Telescope at 2015 March 16.27 UT. The spectrum shows strong Balmer series emission exhibiting P Cygni profiles with velocities of ~2800 km/s. Numerous Fe II emission lines (also with P Cygni profiles) are also seen, along with O I, Si II and Mg II features. This confirms that PNV J18365700-2855420 is a bright classical nova of the Fe II spectral type"

by Ernesto Guido & Nick Howes