Friday, February 9, 2018

Image & Animation of "2018-017A" a.k.a. #Starman

On February 06, 2018 at 20:45 UT, SpaceX successfully launched the Falcon Heavy, a reusable super heavy-lift launch vehicle, introduced as the most powerful rocket currently in operation.

The dummy payload for this test flight was a sports car owned by SpaceX CEO Elon Musk, a midnight cherry, first generation Tesla Roadster. It was selected as "something fun and without irreplaceable sentimental value" to be launched into space on the maiden flight of the Falcon Heavy rocket. The purpose of including the Roadster on the maiden flight was to demonstrate that the Falcon Heavy can launch payloads as far as the orbit of Mars.

Sitting in the driver's seat of the Roadster is "Starman", a dummy astronaut clad in a SpaceX spacesuit. He has his right hand on the steering wheel and left elbow resting on the open window sill. Starman is named for the David Bowie song "Starman". The car's sound system was looping the symbolic Bowie songs "Space Oddity" and "Life on Mars?". A copy of Douglas Adams' 1979 novel "The Hitchhiker's Guide to the Galaxy" is in the glovebox, along with a towel and a sign on the dashboard that reads "Don't Panic!" (two references to the book).

Credit: Spacex

On February 09.4, 2018 I performed follow-up of the #Starman #TeslaRoadster (officially designated 2018-017A) remotely from MPC code H06 (Mayhill, New Mexico; iTelescope network) through a 0.25-m f/3.4 reflector + CCD. Click on the image below for a bigger version.

While below you can see a short animation showing the motion of Starman in about 20 minutes. Each frame is a 60-second exposure. North is up, East to the left.

In the hours after the successful Falcon Heavy launch, a live video feed of the Roadster and Starman from three cameras mounted inside and on booms attached to the outside of the vehicle was broadcast on YouTube. It was expected to last for about twelve hours until the on-board batteries were depleted; however, the livestream lasted for just over four hours. Full video stream of the car as it creates spectacular views of Earth from space is still available, see Youtube video below.

By Ernesto Guido

Thursday, February 8, 2018

Comets & Asteroids - Summary Aug through Dec 2017

During the 5-month period Aug through Dec 2017, 22 new comets were discovered, cometary activity was detected for 5 previously discovered object (earlier designated as an asteroid) and there were 5 comet  recoveries. "Current comet magnitudes" & "Daily updated asteroid flybys" pages are available at the top of this blog (or just click on the underline text here). See below for the "Other news" section. 

The dates below refer to the date of issuance of CBET (Central Bureau Electronic Telegram)  which reported the official news & designations.

- Comet Discoveries

Aug 17 Discovery of P/2017 P1 (PANSTARRS)
Aug 23 Discovery of C/2017 P2 (PANSTARRS)

Sep 22 Discovery of P/2017 R1 (PANSTARRS)
Sep 22 Discovery of C/2017 S2 (PANSTARRS)
Sep 27 Discovery of C/2017 S3 (PANSTARRS)
Sep 29 Discovery of P/2017 S5 (ATLAS)

Comet P/2017 S5 - Credit: ATLAS survey

Oct 08 Discovery of C/2017 S6 (CATALINA)
Oct 08 Discovery of C/2017 S7 (LEMMON)
Oct 16 Discovery of C/2017 T1 (HEINZE)
Oct 25 Discovery of C/2017 T2 (PANSTARRS)
Oct 28 Discovery of P/2017 S8 (PANSTARRS)
Oct 28 Discovery of P/2017 S9 (PANSTARRS)
Oct 28 Discovery of C/2017 T3 (ATLAS)
Oct 29 Discovery of C/2017 U2 (FULS)

Nov 13 Discovery of P/2017 U3 (PANSTARRS)
Nov 20 Discovery of C/2017 U4 (PANSTARRS)

Dec 03 Discovery of C/2017 U5 (PANSTARRS)
Dec 19 Discovery of C/2017 W2 (LEONARD)
Dec 19 Discovery of P/2017 W3 (GIBBS)
Dec 19 Discovery of C/2017 X1 (PANSTARRS)
Dec 31 Discovery of C/2017 Y1 (PANSTARRS)
Dec 31 Discovery of C/2017 Y2 (PANSTARRS)

- Cometary activity detected

Aug 03 Following the announcement on CBET 4415 of the possible connection of 2017 MB_1 and the alpha Cap meteor shower, P. Birtwhistle, Great Shefford, Berkshire, England, re-examined his CCD images of 2017 MB_1 taken using a 0.40-m Schmidt-Cassegrain reflector on several dates. There are no traces of cometary activity on co-added exposures taken on July 4.04 (10 min exposure time) and 5.04 UT (30 min total exposure), but on July 25.11, stacked exposures totalling 7.2 min show a possible very faint, thin, straight tail in p.a. 260 deg, appearing detached from the main object, starting at a distance of 35" and extending to 90" from 2017 MB_1. The images from July 25 were taken in brightening nautical twilight (solar altitude -12.8 to -12.0 degrees), but he is reasonably confident that the possible tail is real and not an artifact.

Aug 11 Cometary activity detected in the NEOWISE images containing minor planet 2014 XK_6

Aug 25 Cometary activity detected in 2007 RS_41 = P/2017 Q2 (LONEOS)

Sep 28 Cometary activity detected in 2006 UR_111 (SPACEWATCH) = P/2017 S4

Dec 13 Cometary activity detected in 2000 XO_8

- Comet Recoveries

Aug 03  Recovery of P/2010 D1 (WISE) as P/2017 O2
Aug 22  Recovery of P/2008 T4 (HILL) as P/2017 Q1
Aug 26  Recovery of P/2012 T1 (PANSTARRS) as P/2017 O3
Sep 20  Recovery of P/2010 P4 (WISE) as P/2017 S1
Nov 20  Recovery of P/2011 VJ_5 (LEMMON) as P/2017 W1

Oct 09 CBET 4442 reports that the following name has been voted upon by the IAU Working Group on Small Body Nomenclature for a recently discovered comet:

Designation (Name)                     Discovery Reference
351P/Wiegert-PANSTARRS             CBET 4439*
C/2017 O1 (ASASSN)                     CBET 4414

* Further to CBET 4298, G. V. Williams (Minor Planet Center) has linked a reported comet from 2007 to comet P/2016 P2. The comet has been given the permanent number 351P and year designations P/2016 P2 = P/1998 U8 = P/2007 R11.

Further to CBETs 4376 and 4439, the following permanent numbers have been assigned to short-period comets based upon their being securely observed at multiple returns to perihelion.

Designation/Name         Provisional Designations                 Reference
352P/Skiff                     P/2000 S1 = P/2017 L1                    CBET 4402
353P/McNaught            P/2009 S2 = P/2017 M1                   CBET 4404
354P/LINEAR              P/2010 A2 = P/2017 B5                    CBET 4405
355P/LINEAR-NEAT     P/2004 T1 = P/2017 M2                   CBET 4406
356P/WISE                   P/2010 D1 = P/2017 O2                    CBET 4441
357P/Hill                       P/2008 T4 = P/2017 Q1                    CBET 4422
358P/PANSTARRS       P/2012 T1 = P/2017 O3                    CBET 4425
359P/LONEOS              P/2007 RS_41 = P/2017 Q2             CBET 4424
360P/WISE                    P/2010 P4 = P/2017 S1                    CBET 4429
361P/Spacewatch          P/2006 UR_111 = P/2017 S4            CBET 4433
362P/(457175)              P/2008 GO_98                                   CBET 4411

- Other news

Aug 06 Asteroid 2012 TC4 has been recovered. Close approach on Oct. 12 at ~50200 km. Images from 2012 available here while images & animation of Oct. 2017 close approach are available here.

Aug 17 New paper on Arxiv by Jian-Yang Li et al. : "The Unusual Apparition of Comet 252P/2000 G1 (LINEAR) and Comparison with Comet P/2016 BA14 (PanSTARRS)"

Sep 01 Goldstone Radar Images of asteroid (3122) Florence. Florence will approach  within 0.047 AU on 2017 September 1 (FOTO). Radar Reveals Two Moons Orbiting Asteroid Florence.

Credit: Goldstone

Sep 16 New paper on Arxiv by Snodgrass et al. : "The Main Belt Comets and Ice in the Solar System"

Sep 20 NASA’s Hubble Space Telescope helped an international team of astronomers find that an unusual object in the asteroid belt is, in fact, two asteroids orbiting  each other that have comet-like features. These include a bright halo of material,  called a coma, and a long tail of dust. The time-lapse video below, assembled from a set of Hubble Space Telescope photos, reveals two asteroids orbiting each other that have comet-like features. The asteroid pair, called 2006 VW139/288P, was observed in September 2016, just before the asteroid made its closest approach to the Sun.

Credits: NASA, ESA, and J. DePasquale and Z. Levay (STScI)

Sep 29 NASA's Hubble Observes the Farthest Active Inbound Comet Yet Seen  - Paper by Jewitt et al. available here.

Credits: NASA, ESA, and D. Jewitt (UCLA)

Oct 04 CBET 4435, CBET 4436, CBET 4440 (Oct.09) & CBET 4459 (Dec. 08) report that the following minor planets are binaries systems: 2017 RV1; (23621) 1996 PA; (10132) LUMMELUNDA; (3378) SUSANVICTORIA

Oct 11 New paper on Arxiv by Meech et al: "CO-Driven Activity in Comet C/2017 K2 (PANSTARRS)"

Oct 25 The first clear case of an interstellar object A/2017 U1. According to CBET 4450 "inadvertently designated as comet C/2017 U1 on MPEC 2017-U181 (and changed to A/2017 U1) with no claimed cometary appearance by anyobservers appears to have hyperbolic orbital elements". A/2017 U1 was discovered Oct. 19 by the University of Hawaii's Pan-STARRS 1 telescope on Haleakala during the course of its nightly search for Near-Earth Objects for NASA. appears to have originated from outside the solar system, coming from somewhere else in our galaxy. If so, it would be the first "interstellar object" to be observed and confirmed by astronomers. According to MPEC 2017-V17: "the object A/2017 U1 receives the permanent designation 1I and the name ʻOumuamua.  The name, which was chosen by the Pan-STARRS team, is of Hawaiian origin and reflects the way this object is like a scout or messenger sent from the distant past to reach out to us (ʻou means reach out for, and mua, with the second mua placing emphasis, means first, in advance of). Correct forms for referring to this object are therefore: 1I; 1I/2017 U1; 1I/ʻOumuamua; and 1I/2017 U1 (ʻOumuamua).

Oct 27 Comet 96P/Machholz in the LASCO C3 camera on ESA/NASA SOHO.

Credit: SOHO

Dec 08 New Outburst of 174P/Echeclus


Dec 22 Radar images of asteroid (3200) Phaethon via Arecibo Radar

by Ernesto Guido

Saturday, January 20, 2018

Possible Nova in Circinus

Following the posting on the Central Bureau's Transient Object Confirmation Page about a possible Nova in Circinus (TOCP Designation: PNV J13532700-6725110) I performed some follow-up of this object through a TEL 0.43-m f/6.8 reflector + CCD from MPC Code Q62 (iTelescope Observatory, Siding Spring). 

On images taken on January 20.6, 2018 I can confirm the presence of an optical counterpart with R-filtered CCD magnitude +8.09 & V-filtered CCD magnitude +8.33 at coordinates: 

R.A. = 13 53 27.57, Decl.= -67 25 01.0 

(equinox 2000.0; Gaia DR1 catalogue reference stars for the astrometry).

This transient has been reported to CBAT/TOCP by John Seach, Chatsworth Island, NSW, Australia. Discovery made with a DSLR with 50 mm f/1.2 lens.

Below my confirmation image (single unfiltered 60-sec exposure through a 0.43-m f/6.8 reflector + CCD; MPC Code Q62). Click on the image for a bigger version: 

An animation showing a comparison between the confirmation image and the archive POSS2/UKSTU Red plate (1997-03-31). Click on the animation for a bigger version: 

UPDATE - January 31, 2018

According to CBET 4482 issued on January 30, Spectroscopy by Strader et al., obtained with the 4.1-m Southern Astrophysical Research Telscope (+ Goodman spectrograph) at Cerro Pachon, Chile, on Jan. 21.28 UT shows clear P-Cyg profiles in the Balmer lines, with the absorption troughs located about 1300 km/s blueward of the rest wavelength (emission FWHM about 1500 km/s), and a number of Fe II lines (some of which also have P-Cyg profiles) -- suggestive of a "Fe II"-type nova. See also ATel #11209. While a low-resolution spectroscopic image by S. Kiyota that shows a strong hydrogen emission line is available here.

This nova has been designated NOVA CIRCINI 2018.

by Ernesto Guido

Monday, January 15, 2018

Possible Bright Nova in Musca

Following the posting on the Central Bureau's Transient Object Confirmation Page about a possible Nova in Musca (TOCP Designation: PNV J11261220-6531086) we performed some follow-up of this object through a TEL 0.50-m f/6.8 reflector + CCD + focal reducer from MPC Code Q62 (iTelescope Observatory, Siding Spring).

On images taken on January 15.57, 2018 we can confirm the presence of an optical counterpart with R-filtered CCD magnitude ~6.3 at coordinates:

R.A. = 11 26 14.95, Decl.= -65 31 24.1

(equinox 2000.0; Gaia DR1 catalogue reference stars).

This transient has been reported to CBAT/TOCP by Rob Kaufman, Bright, Victoria, Australia. Discovery image (taken with Canon 650D & 55mm lens) is available here. He also posted a low-resolution spectrum that "shows strong hydrogen emissions as well as FeII lines":

Credit: R. Kaufman

Below you can see our confirmation image (single 30-sec exposure through a 0.43-m f/6.8 reflector + CCD), click on it for a bigger version:

An animation showing a comparison between our confirmation image and the archive POSS2/UKSTU Red plate (1998-03-19). Click on it for a bigger version:

UPDATE - January 16, 2018

According to CBET 4472 this transient could be a classical "Fe II"-type nova and it has been designated NOVA MUSCAE 2018.

by Ernesto Guido & Alfonso Noschese

Friday, December 8, 2017

New Outburst of 174P/Echeclus

On December 08, 2017 B. Skiff reported on mpml mailing list, that the centaur 174P/Echeclus  (also known as 60558 Echeclus) "seems to be at least 4 mag brighter than expected, and indeed as it appeared at the start of last night's images.  The Dec 7 series shows the outburst in progress on images taken near 2:00 and 2:48 UT; it is much brighter now (Dec 8 about 3:30 UT)". Last observations before this outburst had this object at around magnitude 18.

Prompted by this alert, I perfomed some follow-up of 174P/Echeclus and I can confirm that this object is experiencing a bright phase. Unfiltered exposures, 30-seconds each, obtained  remotely from Q62 (iTelescope network) on 2017, December 08.57 (through a 0.50-m f/6.8 astrograph + CCD + f/4.5 focal reducer) reveal 174P as a bright featureless star-like object of magnitude ~14.1 N (click on the image below for a bigger version).

This very interesting object was discovered by Spacewatch in 2000 and initially classified as a minor planet with provisional designation 2000 EC98 (its final minor planet designation is 60558 Echeclus). The presence of coma around it was first detected by Choi and Weissman (2006) on 2005 December 30.50 UT with the Palomar 5m telescope. Soon after, the object was given the periodic comet designation 174P/Echeclus. During the years, it experienced many outbursts. You can find info and images on all these past bright phases on this blog.

by Ernesto Guido

Sunday, November 12, 2017

Comets & Asteroids - Summary for July 2017

During the month of July 2017, 2 new comets were discovered and cometary activity was detected for 1 previously discovered object (earlier designated as an asteroid). "Current comet magnitudes" & "Daily updated asteroid flybys" pages are available at the top of this blog (or just click on the underline text here). See below for the "Other news" section.

The dates below refer to the date of issuance of CBET (Central Bureau Electronic Telegram)  which reported the official news & designations.

- Comet Discoveries

Jul 01 Discovery of C/2017 M5 (TOTAS)
Jul 24 Discovery of C/2017 O1 *

* Note on CBET 4426 issued on August 26: After considerable discussion, the IAU "Working Group for Small Body Nomenclature" (formerly the IAU "Committee for Small Body Nomenclature" and the IAU "Small Bodies Names Committee") has decided to accept the name "ASASSN" for comet C/2017 O1 (cf. CBET 4414).

- Cometary activity detected

Jul 03 Cometary activity detected in Hilda-type minor planet (457175) 2008 GO_98 *

* The following permanent number has been assigned on CBET 4442 issued on October 09: 362P/(457175)P/2008 GO_98

- Other news

Jul 5 CBET 4412 reports that minor planet (7344) SUMMERFIELD is a binary system with an orbital period of 17.41 +/- 0.01 hr.  The primary shows a period of 2.58975 +/- 0.00003 hr and has a lightcurve amplitude of 0.17 mag at solar phases 9-15 degrees, suggesting a nearly spheroidal shape.  Mutual eclipse/occultation events that are 0.03- to 0.07-magnitude deep indicate a secondary-to-primary mean-diameter ratio of 0.18 +/- 0.03.  The mean absolute R magnitude in the Cousins system is H_R = 12.88 +/- 0.08, assuming the phase relation slope parameter G = 0.24 +/- 0.11.

Credit: Kokotanekova et al

Jul 12 CBET 4413 report the discovery of an apparent satellite (S/2017 (113) 1) of minor planet (113) Amalthea from observations made of the Tycho Catalogue star 1878-01081-1 (magnitude V = 10.0) during an occultation by the minor planet (which was at V = 12.9) on 2017 Mar. 14.167 UT.  A total of ten observation sites recorded seven positive events and three negative events for (113), two of which are attributed to the possible satellite.

Credit: IOTA / Brad Timerson

by Ernesto Guido                        

Wednesday, October 11, 2017

New Close Approach by Asteroid 2012 TC4

Asteroid 2012 TC4 was discovered by F51 Pan-STARRS 1, Haleakala on images taken on 2012, Oct. 04.4 with a 1.8-m Ritchey-Chretien + CCD. Just eight days after its discovery, on 2012 Oct. 12, this object passed at about 0.25 LD from Earth

After exactly 5 years, 2012 TC4 will have a new close approach with our planet that will provide astronomers with a valuable opportunity to learn more about its orbit and composition and to test the network of observatories and scientists who work with planetary defense. This asteroid was not observed since the week it was discovered in October 2012 and it has been recovered by astronomers using one of the European Southern Observatory's 8.2-meter telescopes at the Very Large Telescope (VLT) on July 27, 2017 at an apparent magnitude of 26.8 (making it the faintest Near Earth Asteroid so far measured).

Credit: ESO/ESA NEOCC/Hainaut (ESO), Micheli (ESA) & Koschny (ESA)

2012 TC4 has an estimated size of 12 m - 27 m (H=26.7) and it will have a close approach with Earth at about 0.13 LD (Lunar Distances = ~384,000 kilometers) or 0.00034 AU (1 AU = ~150 million kilometers) at 0542 UT on 12 Oct. 2017 and it will reach the peak magnitude ~13. (For comparison, the asteroid that hit Earth’s atmosphere near Chelyabinsk, Russia, in February 2013 was roughly 20 meters across). The rapid rotation and lightcurve amplitude (rotation period of 0.2038 hours with a brightness variation of 0.93 magnitude) suggest that the 2012 TC4 is an elongated, monolithic body (a rubble pile would have spun itself apart). Non-principal axis rotation suggests that it probably has a complex (non-ellipsoidal) shape. 2012 TC4 should be detectable at Goldstone from about Oct. 9 - 16, but not at the moment of closest approach, when it will be too far south for Goldstone to track.

Below you can see my image (single 120-second exposure) of 2012 TC4 obtained on 2017, Oct. 11.35, few hours before its close approach. At the moment of the shot, the asteroid was of magnitude ~15.9 and moving at ~24"/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). 

The short animation below is showing the movement of 2012 TC4 (two consecutive 120-second exposure). Click on the thumbnail below to see the animation (North is up, East is to the left).

Thanks to the new observations following its 2017 recovery, it became clear that new orbit solution precludes a possible impact in 2050: "2012 TC4 would miss the keyhole that would lead to an impact with Earth in 2050. This plot shows the b-plane—the asymptotic location of TC4 relative to the Earth before the Earth's gravity starts bending the trajectory of TC4. The b-plane intersections for progressive orbit solutions is shown by the ellipses (dashed lines show 1-σ uncertainties, solid lines show 3-σ uncertainties), while the red dots show the b-plane coordinates that lead to an impact in 2050. Starting with the Sept 28 solution, the 3-σ uncertainites fall well clear of the red dots, indicating that the asteroid will miss the Earth in 2050. Future impacts beyond that date have not been ruled out."

Credit: The 2012 TC4 Observing Campaign

by Ernesto Guido