| 词条 | 2017 VR12 | |||||
| 释义 |
| minorplanet = yes | name = {{mp|2017 VR|12}} | background = #FFC2E0 | image = 2017 VR12 radar 2018-03-07 DSS13 to GBT bistatic.gif | image_size = 260 | caption = Goldstone/Green Bank Telescope radar images of {{mp|2017 VR|12}}[1] | discovery_ref = [2] | discoverer = Pan-STARRS 1 | discovery_site = Haleakala Obs. | discovered = 10 November 2017 {{small|(first observed only)}} | mpc_name = {{mp|2017 VR|12}} | alt_names = | pronounced = | named_after = | mp_category = NEO{{·}}PHA Apollo {{·}}Amor [2]{{efn|name=Amor-vs-Apollo}} | orbit_ref = | epoch = 23 March 2018 (JD 2458200.5) | uncertainty = 3 | observation_arc = 118 days | aphelion = 1.7389 AU | perihelion = 1.0004 AU | semimajor = 1.3697 AU | eccentricity = 0.2696 | period = 1.60 yr (585.50 d) | mean_anomaly = 8.8927° | mean_motion = {{Deg2DMS|0.6149|sup=ms}} / day | inclination = 9.2247° | asc_node = 347.32° | arg_peri = 180.74° | moid = {{convert|0.0077|AU|LD|abbr=on}} | dimensions = {{val|160|×|100|u=m}}[6] | mean_diameter = {{val|160|ul=m}}[1] | rotation = {{val|1.4|ul=h}}[1] {{val|1.5|u=h}}[9] | albedo = | spectral_type = V [1] | abs_magnitude = 20.6 }}{{mp|2017 VR|12}} is a sub-kilometer asteroid with a somewhat elongated and angular shape, approximately {{convert|160|m|ft|abbr=off|sigfig=1|sp=us}} in diameter. It is classified as near-Earth object and potentially hazardous asteroid of the Apollo or Amor group.{{efn|name=Amor-vs-Apollo}} The V-type asteroid has a rotation period of approximately 1.5 hours.[9] It was first observed on 10 November 2017 by the 60-inch Pan-STARRS 1 telescope at Haleakala Observatory in Hawaii.[2] Orbit and classificationIt orbits the Sun at a distance of 1.0–1.7 AU once every 1 years and 7 months (585 days; semi-major axis of 1.37 AU). Its orbit has an eccentricity of 0.27 and an inclination of 9° with respect to the ecliptic. {{mp|2017 VR|12}} is a V-type asteroid with a bright surface.[1] 2018 flyby{{mp|2017 VR|12}} passed 0.0097 AU (3.76 lunar distances) from Earth on 7 March 2018, the closest approach by this asteroid currently known. It brightened to 12th magnitude, making it one of the brightest Near Earth asteroids of the year. It was observed by radar from Goldstone, Green Bank and Arecibo Observatory. Images revealed that {{mp|2017 VR|12}} is a slightly elongated and angular body with a size of approximately 160 by 100 meters.[1][18][6]{{clear|left}}Physical characteristicsImages obtained at Green Bank and Arecibo observatories in 2018, revealed that {{mp|2017 VR|12}} is a slightly elongated and angular body with a size of approximately 160 by 100 meters.[1][18][6] Rotation periodOn 5 March 2018, a rotational lightcurve was obtained from photometric observations by astronomers at the Northolt Branch Observatories. Lightcurve analysis gave a rotation period of 1.5 hours with a brightness amplitude between 0.4 and 0.5 magnitude ({{small|U=n.a}}).[9] GalleryNotes{{notelist|refs={{efn|name=Amor-vs-Apollo|1=It is either an Amor or an Apollo asteroid, depending on the definition of those orbital classes: JPL SBDB defines Apollo asteroids as those with a perihelion of less than 1.017 AU (smaller than Earth's aphelion),[28] while the MPC uses a threshold of 1.000 AU (Earth's semi-major axis). {{mp|2017 VR|12}}'s perihelion is 1.0004 AU.}}}} References1. ^{{cite web| url=https://www.facebook.com/NBObservatories/posts/1879336162101246| publisher=Northolt Branch Observatories| title=Near Earth asteroid 2017 VR12| date=15 February 2018| access-date=6 March 2018}} [5][6][7][8][9]2. ^{{cite web| url=https://www.facebook.com/NBObservatories/posts/1871743436193852| publisher=Northolt Branch Observatories| title=Near Earth asteroids 2017 VR12, (505657) 2014 SR339 and (508871) 2003 CN17| date=26 February 2018| access-date=6 March 2018}} 3. ^{{cite web| url=https://www.facebook.com/NBObservatories/posts/1879336162101246| publisher=Northolt Branch Observatories| title=Near Earth asteroid 2017 VR12| date=5 March 2018| access-date=6 March 2018}} 4. ^1 2 {{cite web| url=http://www.newsweek.com/asteroid-2017-vr12-telescope-watch-831042| title=2017 VR12: Asteroid Could Be Bigger Than the Empire State Building—Here’s How to See It| website=newsweek.com| first=Katherine| last=Hignett| date=6 March 2018| access-date=6 March 2018}} 5. ^1 2 3 {{cite web |title = 2017 VR12 |work = Minor Planet Center |url = https://www.minorplanetcenter.net/db_search/show_object?object_id=2017+VR12 |accessdate = 3 March 2018}} 6. ^1 2 3 {{cite web |last1 = Wells |first1 = G. |last2 = Bamberger |first2 = D. |date = 5 March 2018 |title = Lightcurve of 2017 VR12 |publisher = Northolt Branch Observatories |url = https://www.facebook.com/NBObservatories/posts/1879322858769243 |accessdate = 6 March 2018}} 7. ^1 2 3 4 5 6 7 {{cite web |title = Goldstone Radar Observations Planning: Asteroid 2017 VR12 |publisher = NASA |url = https://echo.jpl.nasa.gov/asteroids/2017VR12/2017VR12_planning.2018.html |accessdate = 12 March 2018}} 8. ^1 2 3 [https://twitter.com/AreciboRadar/status/971159944442662918 #TeamRadar at @NAICobservatory observed asteroid 2017 VR12 last night.] 3:05 PM - 6 Mar 2018 9. ^1 {{cite web |title=NEO Groups |url=https://cneos.jpl.nasa.gov/about/neo_groups.html |publisher=Jet Propulsion Laboratory |accessdate=12 March 2018}} }} External links
6 : Apollo asteroids|Amor asteroids|Minor planet object articles (unnumbered)|Discoveries by Pan-STARRS|Near-Earth objects in 2018|Astronomical objects discovered in 2017 |
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