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Showing posts with label (Orbit type: Apollo ). Show all posts
Showing posts with label (Orbit type: Apollo ). Show all posts

Jan 30, 2017

The Near-Earth Object 2016 WF9 , the Flyby, the Hullabaloo, and the Facts

The Discovery

An artist’s rendition of 2016 WF9 as it passes Jupiter’s orbit inbound
toward the Sun. Image: Courtesy NASA/JPL-Caltech
On 2016 November 27 at 6:27:07.77(UTC) the NEOWISE project took the first of a series of images of a "new object." A report for this new object was submitted to the Minor Planet Center(MPC) The "object"(with its observations) was posted to the NEO Confirmation Page. Observers from four other observatories submitted follow-up observations, and on 2016 November 30, 04:19 (UTC) the MPC issued a Minor Planet Electronic Circular (MPEC 2016-W125: 2016 WF9) announcing the discovery. This object was given the provisional designation 2016 WF9. This designation tells the world that this asteroid was discovered in the year 2016 during the half-month of November 16-30(W) and it was the 231st(F9) discovery of that half-month.

Follow-up After Discovery 

After the MPC had issued The Minor Planet Electronic Circular announcing the discovery, follow-up observations were made, and prediscovery observations were found adding up to a total of 61 observations spanning 111 days. Each observations records were in the sky 2016 WF9 was seen from the given location at the given time. Given that asteroid and comets follow the laws of planetary motion and move through the solar system in elliptical orbits each observation eliminates many  possibilities of where in the solar system the asteroid can be in the future. Near-Earth Object observational data is generally made available within 24 hours after it is submitted to the MPC.  Anyone who has the knowledge and the software can do their own orbit determination. The available observational data for 2016 WF9 rules out any impact for the foreseeable future.  It should also be noted that observations from other observatories serve as a cross check.

What set 2016 WF9 apart from other Near-Earth Objects is first it has a Tisserand Parameter of 2.893. Most asteroids have a Tisserand Parameter greater than 3, and most Jupiter Family Comets have a Tisserand Parameter between 2 and 3. In other words, it has a "comet-like" orbit.  The second thing about 2016 WF9 is it is rather dark. Given that  2016 WF9 has a "comet-like" orbit and is rather dark lends astronomers to believe it may have cometary origins; however, no cometary activity has been observed yet. 

2016 WF9 Comes to the  Attention of the General Public

On December 29, 2016, NASA call 2016 WF9 to the attention of the public at large by issuing the press release titled "NASA's NEOWISE Mission Spies One Comet, Maybe Two." The press release reported information about the comet C/2016 U1 NEOWISE and 2016 WF9 including information on an unremarkable close-approach and stated: "The trajectory of 2016 WF9 is well understood, and the object is not a threat to Earth for the foreseeable future." In the days that follow this story was picked up by other news outlets, some which blurred the line between journalism and creative writing.

Keep in mind as a story moves through the blogosphere it changes like the "telephone game." The original story is misread, poorly translated, misunderstood, etc. then rewritten by other writers with the wrong information. Then other writers then use the revised story as a source for new stories adding to the madness. One should seek out the original story(and see if it is reliable).
Background
(as of 2017-01-29 ) 
  • Object: 2016 WF9
  • Orbit Type:  Apollo [NEO] Potentially Hazardous Asteroid (NOTE: this is over hundreds if not  thousands of years
  • Approximate Diameter:   270 m - 590 m( 885.827 feet to  1935.696 feet)(Absolute Magnitude: H= 20.2)
  • On the Sentry Risk Table: No (Removed ) 2016-12-20 16:00
  • On the NEODyS CLOMON2 risk page: No (Removed )
  • First(Precovery) Observation was made: 2016 10 10.42213
  • First(Precovery) Observed by: Pan-STARRS 1, Haleakala (MPC Code F51) The Precovery  M.P.E.C.: MPEC 2017-A66 : DAILY ORBIT UPDATE (2017 JAN. 9 UT)
  • Discovery (First) observation was made: 2016 11 27.26884
  • Discovery (First )observation by: NEOWISE (MPC Code C51)The Discovery M.P.E.C.: MPEC 2016-W125: 2016 WF9
  • Last Observation (publish): 2017 01 29.18221  (by  LPL/Spacewatch II (MPC Code 291 )  )
  • Data-Arc Span (publish): 111 days
  • Number of Optical Observations(published): 61
  • Observatories Reporting (Published) Observations(MPC Code):
    • (291) LPL/Spacewatch II, US/Arizona. 
    • (474) Mount John Observatory, Lake Tekapo, New Zealand.
    • (807) Cerro Tololo Observatory, La Serena, Chile. 
    • (C51) NEOWISE
    • (F51) Pan-STARRS 1, Haleakala, US/Hawaii.
    • (Q64) Siding Spring-LCOGT B, Australia/NSW.
    • (T12) Mauna Kea-UH/Tholen NEO Follow-Up (2.24-m), US/Hawaii.
  • Perihelion Distance: 0.9817420310009939(AU)
  • Aphelion Distance:  4.759885397693941
  • Earth MOID: 0.0145594 AU ( 5.666 (LD)) or 1,353,380.78  miles (2,178,055.239 (KM))
  • Next Close-Approach to Earth:  Will safely pass Earth on 2017-Feb-25 at a Nominal Distance of  0.340740651006311 (AU) (132.607 (LD)) or  31,673,822.283 miles (50,974,075.848 (KM)) to put things in perspective "If" the Earth Was the Size of a Basketball this would be  ~ 3,126.54 feet (952.97meters) away) 
Correction


This past has been corrected to show that 2016 WF9 was at one listed on the JPL Sentry and NEODyS risk list. see The Tracking News 30 November 2016 #2016 WF9 The author thanks the reader for the correction,




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Jan 17, 2017

The Asteroid 2012 TC4 is Making a Safe Close-Approach on October-12-2017 Please Stand By For a Media Storm

The First in a Series
This artist's concept shows a broken-up asteroid.
ImageCourtesy NASA/JPL-Caltech 
On October 12, 2017, the asteroid 2012 TC4 is projected to make an exceptionally close approach to Earth, and it is possible that the media (alternative, mainstream,  print, broadcast, and social) will go wild. Writeups will range from well written to poorly written, originally written to carbon copies, well research to poorly research, well intentioned to bad intentioned, and so forth. How is the consumer of media to make heads or tails of the hodgepodge of choices out there? The author plans a series of posts to give some background on 2012 TC4 in particular, some general knowledge about asteroids, their orbit, asteroid observing, asteroid risk list, and source information, to help the read navigate the mishmash of media out there.

What makes the Close-Approach on October 12, 2017, exceptional?

If we count 2008 TC3 and 2014 AA(both were small and impacted the Earth and would tie for first) 2012 TC4 could come in as the sixth closest known approach to date.  While there is some uncertainty about how close the close-approach will be, there is sufficient observational data to rule out an impact on October 12, 2017, When talking about astronomical distances it can be tough to wrap one's head around this can lead one to use of analogies such as close shave which is not aways helpful. If one uses a basketball to serve as a model for the Earth it may be easier to grasp.

The Model  (the Basketball Size Earth) 

  • Earth (Equatorial) radius: 4.2634965e-5 AU 3963.17 miles (6378.1 KM) - for the model 4.69507082121091 inches (11.93 CM)
  • Earth (Equatorial) Circumference(assuming around Earth): 0.000267883358316 AU 24,901.32 miles (40,074.78 KM) -for the model 29.5 inches (74.93 CM)
  • ISS(Perigee): 2.67383e-6 AU 248.55 miles (400.00 KM) -for the model 0.29 inches ( 0.75CM)
  • ISS(apogee): 2.7407e-6 AU 254.76 miles (400.00 KM) -for the model 0.3 inches ( 0.77CM)
  • Geosynchronous orbit: 0.00023921463 AU (0.093 Lunar Distance (LD)) or 22236.39 miles (35786.00 KM)  -for the model (after subtracting the radius)- 2.2 feet ( 0.67 M)
  • Lunar Distance (LD): 0.003 AU or 238606.54  22236.39 miles (35786.00 KM)  -for the model (after subtracting the radius)-  23.16 feet (7.06 M)
  • Astronomical Unit: 389.171 Lunar Distance (LD) or 9.296e+7 miles (1.496e+8 KM)   -for the model   1.7 miles  (2.7 KM)

Background
(as of 2017-01-16 ) 


  • Object: 2012 TC4
  • Orbit Type: Apollo [NEO]
  • Approximate Diameter: 15 m - 33 m (  49.2126 feet to 108.268  feet)(Absolute Magnitude: H= 26.7)
  • On the Sentry Risk Table:  Yes 
    •  NOTE this is NOT a prediction of an impact but rather a statement there is insufficient observational data rule out an impact -- for information read  Understanding Risk Pages by Jon Giorgini
  • Torino Scale(NEODyS CLOMON2)0
    • "The likelihood of a collision is zero, or is so low as to be effectively zero. Also applies to small objects such as meteors and bodies that burn up in the atmosphere as well as infrequent meteorite falls that rarely cause damage.."
  • On the NEODyS CLOMON2 risk page: Yes
    • NEODyS Recovery Campaign: 2017-08-31t o 2017-10-24
  • Discovery observation was made: 2012 10 04.467661
  • Discovery observation was made by Pan-STARRS 1 (MPC Code F51) The Discovery M.P.E.C.: MPEC 2012-T18 : 2012 TC4
  • Last Observation (publish): 2012 10 11.74842   (by Volkssternwarte Drebach, Schoenbrunn(MPC code 113))
  • Data-Arc Span (publish): 7 days
  • Number of Optical Observations(published):301
  • Observatories Reporting (Published) Observations(MPC Code):
    • (089) Nikolaev,  Ukraine.
    • (104) San Marcello Pistoiese, Italy.
    • (113) Volkssternwarte Drebach, Schoenbrunn, Germany.
    • (204) Schiaparelli Observatory, Italy
    • (291) LPL/Spacewatch II, US/Arizona.
    • (300) Bisei Spaceguard Center-BATTeRS, Japan.
    • (461) University of Szeged, Piszkesteto Stn (Konkoly), Hungary.
    • (470) Ceccano, Italy.
    • (568) Mauna Kea, US/Hawaii.
    • (695) Kitt Peak, US/Arizona.
    • (703) Catalina Sky Survey, US/Arizona.
    • (716) Palmer Divide Observatory, Colorado Springs, US/Colorado.
    • (718) Tooele, US/Utah.  
    • (857) Iowa Robotic Observatory, Sonoita, US/Arizona.
    • (900) Moriyama, Japan.
    • (932) John J. McCarthy Obs., New Milford,  US/Connecticut.
    • (B04) OAVdA, Saint-Barthelemy, Italy. 
    • (B88) Bigmuskie Observatory, Mombercelli, Italy.
    • (C32) Ka-Dar Observatory, TAU Station, Nizhny Arkhyz, Russia.
    • (C77) Bernezzo Observatory, Italy.
    • (E10) Siding Spring-Faulkes Telescope South, Australia/NSW.
    • (F51) Pan-STARRS 1, Haleakala, US/Hawaii
    • (F65) Haleakala-Faulkes Telescope North, US/Hawaii.
    • (G40) Slooh.com Canary Islands Observatory, Canary Islands (Spain).
    • (G48) Doc Greiner Research Obs., Rancho Hildalgo,  US/New Mexico.
    • (H06) iTelescope Observatory, Mayhill, US/New Mexico.  
    • (H17) Angel Peaks Observatory, US/Colorado.
    • (H21) Astronomical Research Observatory, Westfield, US/Illinois.
    • (H36) Sandlot Observatory, Scranton, US/Kansas
    • (J16) An Carraig Observatory, Loughinisland, UK.
    • (J84) South Observatory, Clanfield, UK.
    • (J95) Great Shefford, UK.
  • Perihelion Distance: 0.9337184081730526(AU)
  • Aphelion Distance: 1.877515914032821
  • Goldstone Asteroid Schedule: Yes  2017 Oct ( Needs Astrometry: Yes Physical Ob
  • Near-Earth Object Human Space Flight Accessible Targets Study (NHATS): Yes
Useful Links:

Jan 9, 2017

Confirmation images of the NEO 2017 AF5


A confirmation image of the Near Earth Objects 2017 AF5
on 2017-01-06 from AstroCamp Observatory. Nerpio, Spain - (MPC Code I89)
using itelescope.net's (T7 TEL 0.43-m f/6.8 reflector + CCD)
a stack of 5-60 Second Luminance BIN2 Images
(C) Steven M. Tilley

A confirmation image of the Near Earth Objects 2017 AF5
on 2017-01-06 from AstroCamp Observatory. Nerpio, Spain - (MPC Code I89)
using itelescope.net's (T7 TEL 0.43-m f/6.8 reflector + CCD)
a stack of 5-60 Second Luminance BIN2 Images
(C) Steven M. Tilley

A confirmation image of the Near Earth Objects 2017 AF5
on 2017-01-06 from AstroCamp Observatory. Nerpio, Spain - (MPC Code I89)
using itelescope.net's (T7 TEL 0.43-m f/6.8 reflector + CCD)
a stack of 5-60 Second Luminance BIN2 Images
(C) Steven M. Tilley
A confirmation image of the Near Earth Objects 2017 AF5
on 2017-01-06 from AstroCamp Observatory. Nerpio, Spain - (MPC Code I89)
using itelescope.net's (T7 TEL 0.43-m f/6.8 reflector + CCD)
a stack of 5-60 Second Luminance BIN2 Images
(C) Steven M. Tilley
A confirmation image of the Near Earth Objects 2017 AF5
on 2017-01-07 from AstroCamp Observatory. Nerpio, Spain - (MPC Code I89)
using itelescope.net's (T18 TEL 0.32-m f/8.0 reflector + CCD)
a stack of 5-60 Second Luminance BIN2 Images
(C) Steven M. Tilley
A confirmation image of the Near Earth Objects 2017 AF5
on 2017-01-07 from AstroCamp Observatory. Nerpio, Spain - (MPC Code I89)
using itelescope.net's (T18 TEL 0.32-m f/8.0 reflector + CCD)
a stack of 5-60 Second Luminance BIN2 Images
(C) Steven M. Tilley
A confirmation image of the Near Earth Objects 2017 AF5
on 2017-01-07 from AstroCamp Observatory. Nerpio, Spain - (MPC Code I89)
using itelescope.net's (T18 TEL 0.32-m f/8.0 reflector + CCD)
a stack of 5-60 Second Luminance BIN2 Images
(C) Steven M. Tilley
A confirmation image of the Near Earth Objects 2017 AF5
on 2017-01-07 from AstroCamp Observatory. Nerpio, Spain - (MPC Code I89)
using itelescope.net's (T18 TEL 0.32-m f/8.0 reflector + CCD)
a stack of 5-60 Second Luminance BIN2 Images
(C) Steven M. Tilley
A confirmation image of the Near Earth Objects 2017 AF5
on 2017-01-07 from AstroCamp Observatory. Nerpio, Spain - (MPC Code I89)
using itelescope.net's (T18 TEL 0.32-m f/8.0 reflector + CCD)
a stack of 5-60 Second Luminance BIN2 Images
(C) Steven M. Tilley
A confirmation image of the Near Earth Objects 2017 AF5
on 2017-01-07 from AstroCamp Observatory. Nerpio, Spain - (MPC Code I89)
using itelescope.net's (T18 TEL 0.32-m f/8.0 reflector + CCD)
a stack of 5-60 Second Luminance BIN2 Images
(C) Steven M. Tilley
Background
(as of 2017-01-09 )
 

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Dec 3, 2016

The NEO 2016 WJ1 Has Been Removed from the Sentry Risk Table--Neodys Risk Table List 3 Possible Impacts 2106-2115.

On December 2, 2016 at 21:33(UTC) NASA JPL removed the NEO 2016 WJ1 from the Sentry Risk Table. Whenever an object is posted to one the risk lists (especially if it has a Torino Scale 1 or greater) and it is observable, observers will take a particular interest in it. In the case of 2016 WJ1 many follow-up observations where made and  there was a search in archives for precovery observations. From  November 24, 2016  to December 2, 2016  through the work of many observers from around the world the number of optical observations went from 68  to 240 and  the data-arc span went from 5 days to  4899 days (13.41 yr). This allowed  for the calculation of orbital elements with lower uncertainty and NASA JPL rule out  potential impacts well into the future. Notice: Neodys risk table list 3 possible impacts 2106-2115.
Background
(as of 2016-12-03 )
 
  • Object: 2016 WJ1 
  • Approximate Diameter: 140 m - 310 m (459.318 feet to 1017.06 feet)(Absolute Magnitude: H= 21.382)
  • Orbit Type: Apollo [NEO]- Potentially Hazardous Asteroid
  • On the Sentry Risk Table: No Removed on 2016-12-02 21:33
  • On the NEODyS CLOMON2 risk page: yes
  • Torino Scale(NEODyS CLOMON2): 0
    • The likelihood of a collision is zero, or is so low as to be effectively zero. Also applies to small objects such as meteors and bodies that burn up in the atmosphere as well as infrequent meteorite falls that rarely cause damage."
  • First(Precovery) Observation was made: 2003 07 04.605261
  • First(Precovery) Observed By: Mauna Kea (MPC Code 568) The Precovery M.P.E.C.:MPEC 2016-X21 : 2016 WJ1
  • Discovery (First) observation was made: 2016 11 19.46522
  • Discovery (First )observed by: Mt. Lemmon Survey (MPC Code G96) The Discovery M.P.E.C.: MPEC 2016-W38 : 2016 WJ1
  • Last Observation(publish): 2016 12 02.87233
    (by Nonndorf, Austria. (MPC Code C47 )
  • Data-Arc Span(publish) : 4900 days (13.42 yr)
  • Number of Optical Observations(published): 257
  • Observatories Reporting (Published) Observations(MPC Code):
    • (151) Eschenberg Observatory, Winterthur Switzerland.  
    • (160) Castelmartini,Italy.
    • (203) GiaGa Observatory,Italy.
    • (246) Klet Observatory-KLENOT, Czech Republic.
    • (291) LPL/Spacewatch II,US/Arizona. 
    • (568) Mauna Kea,US/Hawaii.
    • (691) Steward Observatory, Kitt Peak-Spacewatch, US/Arizona.
    • (926) Tenagra II Observatory, Nogales,US/Arizona.  
    • (958) Observatoire de Dax, France.
    • (A17) Guidestar Observatory, Weinheim,Germany.
    • (A48) Povegliano Veronese,Italy.
    • (C47) Nonndorf, Austria.
    • (C77) Bernezzo Observatory, Italy.
    • (E10) Siding Spring-Faulkes Telescope South, Australia/NSW.
    • (F51) Pan-STARRS 1, Haleakala, US/Hawaii.
    • (G96) Mt. Lemmon Survey, US/Arizona.
    • (H06) iTelescope Observatory, Mayhill, US/New Mexico.  
    • (H21) Astronomical Research Observatory, Westfield, US/Illinois.
    • (H45) Arkansas Sky Obs., Petit Jean Mountain South, US/Arkansas.
    • (I52) Steward Observatory, Mt. Lemmon Station,US/Arizona.
    • (J04) ESA Optical Ground Station, Tenerife, Canary Islands (Spain).
    • (J69) North Observatory, Clanfield,UK.
    • (K38) M57 Observatory, Saltrio,Italy.
    • (K61) Rokycany Observatory,Czech Republic.
    • (K65) Cesena,Italy.
    • (K74) Muensterschwarzach Observatory, Schwarzach, Germany.
    • (K88) GINOP-KHK, Piszkesteto, Hungary.
    • (L04) ROASTERR-1 Observatory, Cluj-Napoca, Romania.
    • (Q62) iTelescope Observatory, Siding Spring, Australia/NSW.
    • (T05) ATLAS-HKO, Haleakala, US/Hawaii.
    • (T12) Mauna Kea-UH/Tholen NEO Follow-U (2.24-m),US/Hawaii.
    • (W25) RMS Observatory, Cincinnati,US/Ohio.
    • (W88) Slooh.com Chile Observatory, La Dehesa,Chile.
    • (Y28) OASI, Nova Itacuruba, Brazil.
    • (Z80) Northolt Branch Observatory,UK..
  • Perihelion Distance: 0.6654428764236301  (AU)
  • Aphelion Distance: 2.013952506814137 (AU)
  • Earth MOID: 0.000339358 AU (0.132 (LD)) or 31,545.297 miles (50,767.234 (KM))
  • Close-Approach to Earth: Will safely pass Earth on 2016-December-16 at a Nominal Distance of  0.0538116295342834 (AU) (20.942 (LD)) or 5,004,610.672 miles (8,054,140.158 (KM))
To illustrate on how the addition of observation can lower the uncertainty of orbital elements here is three
screenshot of Find_Orb showing elements and their uncertainty
 
A screenshot of Find_Orb showing orbital elements and uncertainty
 before the addition of the precovery observation.
(2 observationobservation are rejected as outliers) 
Orbital elements:  2016 WJ1
   Perihelion 2017 Feb 7.453335 +/- 0.0146 TT = 10:52:48 (JD 2457791.953335)
Epoch 2017 Feb 16.0 TT = JDT 2457800.5   Earth MOID: 0.0004   Ve: 0.0023
M   5.42420715 +/- 0.0053           Ma: 0.0027                Find_Orb
n   0.63465774060 +/- 0.000456      Peri.   87.68828816 +/- 0.0057
a   1.34104390016 +/- 0.000642      Node    82.04709113 +/- 0.0023
e   0.5040907493 +/- 0.000384       Incl.    2.89419977 +/- 0.0022
P   1.55/567.22d           H 21.3   G  0.15   U  7.6  
q 0.66503607568 +/- 0.000196    Q 2.01705172465 +/- 0.00148
233 of 235 observations 2016 Nov. 19-Dec. 1; mean residual 0".32
 
A screenshot of Find_Orb showing orbital elements and uncertainty 
after the addition of the precovery observation.
(2 observationobservation are rejected as outliers) 
 
Orbital elements:  2016 WJ1
   Perihelion 2017 Feb 7.484044 +/- 0.000243 TT = 11:37:01 (JD 2457791.984044)
Epoch 2017 Feb 16.0 TT = JDT 2457800.5   Earth MOID: 0.0004   Ve: 0.0024
M   5.41286498 +/- 0.00015          Ma: 0.0027                Find_Orb
n   0.63561447057 +/- 1.52e-7       Peri.   87.67637253 +/- 0.00017
a   1.33969786518 +/- 2.14e-7       Node    82.05217334 +/- 0.00022
e   0.5032874712 +/- 8.64e-7        Incl.    2.88944734 +/- 0.000020
P   1.55/566.37d           H 21.3   G  0.15   U  2.3  
q 0.66544471439 +/- 1.26e-6    Q 2.01395101596 +/- 8.71e-7
238 of 240 observations 2003 July 4-2016 Dec. 1; mean residual 0".32
 
A screenshot of Find_Orb showing orbital elements and uncertainty 
with all published observation.
(2 observationobservation are rejected as outliers) 

Orbital elements:  2016 WJ1
   Perihelion 2017 Feb 7.484067 +/- 0.000172 TT = 11:37:03 (JD 2457791.984067)
Epoch 2017 Feb 16.0 TT = JDT 2457800.5   Earth MOID: 0.0004   Ve: 0.0024
M   5.41285007 +/- 0.00010          Ma: 0.0027                Find_Orb
n   0.63561448686 +/- 1.18e-7       Peri.   87.67634890 +/- 0.00015
a   1.33969784228 +/- 1.66e-7       Node    82.05222716 +/- 0.00017
e   0.5032875546 +/- 7.26e-7        Incl.    2.88944241 +/- 0.000019
P   1.55/566.37d           H 21.3   G  0.15   U  2.1  
q 0.66544459133 +/- 1.05e-6    Q 2.01395109323 +/- 7.49e-7
255 of 257 observations 2003 July 4-2016 Dec. 2; mean residual 0".31
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