View source for Astronomy:2022 RM4

{{short description|Near-Earth asteroid 2022}}
{{DISPLAYTITLE:{{mp|2022 RM|4}}}}
{{Infobox planet
| minorplanet = yes
| background = #FFC2E0
| name = {{mp|2022 RM|4}}
| image = Near-Earth_asteroid_2022_RM4.jpg
| caption = The orbit of {{mp|2022 RM|4}} is highly inclined at 38° and takes 3.8 years to orbit the Sun.
| discovery_ref = <ref name="MPEC2022-R162"/>
| discoverer = [[Astronomy:Pan-STARRS|Pan-STARRS]] 2
| discovered = 12 September 2022
| mpc_name = {{mp|2022 RM|4}}
| mp_category = {{Hlist
 | [[Astronomy:Apollo asteroid|Apollo]]
 | [[Astronomy:Near-Earth object|NEO]]
 | [[Astronomy:Potentially hazardous object|PHA]]<ref name=jpldata/>
 }}
| orbit_ref = <ref name="jpldata"/>
| epoch = 2022-Aug-09 ([[Astronomy:Julian day|JD]]&nbsp;2459800.5)
| uncertainty = 5
| observation_arc = 50 days
| moid = {{Convert|0.0032|AU|e3km LD|abbr=unit}}
| jupiter_moid = {{Convert|1.5|AU|e6km|abbr=unit}}
| aphelion = {{val|3.90|ul=AU}} (Q)
| perihelion = {{val|0.98844|u=AU}} (q)
| time_periastron = 3 November 2022
| semimajor = {{val|2.446|u=AU}} (a)
| eccentricity = {{val|0.596}} (e)
| period = {{val|3.83|u=years}}
| inclination = {{val|38.31|u=°}} (i)
| asc_node = {{val|218.2|u=°}} (Ω)
| mean_anomaly = {{val|337.8|ul=°}} (M)
| arg_peri = {{val|181.7|u=°}} (ω)
| dimensions = {{Ubl
 | ≈{{convert|400|m|sigfig=1|abbr=on}}<ref name=esa/>{{efn|name=esa-size}}
 | 290–650 meters{{efn|name=range}}
 }}
| abs_magnitude = 19.8<ref name="MPC-object"/>
}}

'''{{mp|2022 RM|4}}''' is categorized as a [[Astronomy:Potentially hazardous asteroid|potentially hazardous asteroid]] because it is around 400 meters in diameter<ref name=esa/>{{efn|name=esa-size}} and makes close approaches to Earth. It was discovered on 12 September 2022 when it was {{Convert|0.61|AU|e6km|abbr=unit|lk=on}} from Earth and located at [[Declination|declination]] +65 near the northern [[Astronomy:Circumpolar star|circumpolar star]] [[Astronomy:Zeta Draconis|Zeta Draconis]].<ref name="MPEC2022-R162"/>

At 1 November 2022 18:26 [[Physics:Coordinated Universal Time|UT]] it passed {{Convert|0.01536|AU|km LD|abbr=unit|lk=on}} from Earth.<ref name="jpldata"/> As of 1 November 2022 the uncertainty in the close approach distance was ±{{val|77|u=km}}.<ref name="Archive221101"/> The asteroid should have brighten to about [[Astronomy:Apparent magnitude|apparent magnitude]] 14.3 which is roughly the brightness of [[Astronomy:Pluto|Pluto]] and was around 75 degrees from the Sun.<ref name="Mag2022"/> It may have been viewable by experienced amateur observers with a telescope that has an [[Physics:Objective (optics)#Telescopes|aperture]] of around 8-inches or better.<ref name=Earthsky/>

{| class="wikitable" style="font-size: 0.9em;"
|+Earth Approach on 1 November 2022<ref name=jpldata/>
! Date
! JPL Horizons<br />[[Curve fitting|nominal]] geocentric<br />distance ([[Astronomy:Astronomical unit|AU]])
! uncertainty<br />region<br />(3-sigma)
|-
|2022-11-01 18:26 ± 00:01 ||{{Convert|0.01536|AU|e6km|abbr=unit|lk=on}}<ref name="jpldata"/> || ±{{val|77|u=km}}<ref name="CA2022"/>
|}

By 2 November 2022 the asteroid was better placed for the southern hemisphere with a declination of –32.<ref name="Mag2022"/> [[Astronomy:Goldstone Solar System Radar|Goldstone Solar System Radar]] using the [[Engineering:Canberra Deep Space Communication Complex|Canberra Deep Space Communication Complex]] 70–meter Deep Space Station 43 and [[Astronomy:Australia Telescope Compact Array|Australia Telescope Compact Array]] observed the asteroid on 2 November 2022.<ref name=Goldstone/> It then came to perihelion (closest approach to the Sun) on 3 November 2022.<ref name="jpldata"/>

== See also ==
* List of asteroid close approaches to Earth in 2022 beyond 1 LD
* List of asteroid close approaches to Earth in 2023 beyond 1 LD
* {{mpl|2015 TB|145}}

== Notes ==
{{notelist|refs=

{{efn|name=esa-size|An [[Astronomy:Absolute magnitude#Solar System bodies (H)|absolute magnitude]] of 19.8 and assumed [[Earth:Albedo#Astronomical albedo|albedo]] of 0.14 gives a diameter of 389 meters (or ≈400 meters after rounding).}}

{{efn|name=range|Diameter range based on Minor Planet Center [[Astronomy:Absolute magnitude#Solar System bodies (H)|absolute magnitude]] value of 19.8 and assumed [[Earth:Albedo#Astronomical albedo|albedo]] range of 0.25 to 0.05.}}

}} <!-- end of notelist -->

== References ==
{{Reflist|refs=

<ref name="MPEC2022-R162">{{cite web
  |title=MPEC 2022-R162 : 2022 RM4
  |publisher=IAU Minor Planet Center
  |date=2022-09-25
  |url=https://www.minorplanetcenter.net/mpec/K22/K22RG2.html
  |access-date=2022-10-09}} (K22R04M)</ref>

<ref name=jpldata>{{cite web
  |title=JPL Small-Body Database Browser: (2022 RM4)
  |url=https://ssd.jpl.nasa.gov/tools/sbdb_lookup.html#/?sstr=2022+RM4&view=OPC
  |publisher=[[Organization:Jet Propulsion Laboratory|Jet Propulsion Laboratory]]
  |access-date=2022-10-28}}</ref>

<ref name=esa>{{cite web
  |title=ESA Summary: 2022RM4
  |publisher=[[Organization:European Space Agency|European Space Agency]]
  |url=https://neo.ssa.esa.int/search-for-asteroids?sum=1&des=2022RM4
  |archive-url=https://web.archive.org/web/20221009163439/https://neo.ssa.esa.int/search-for-asteroids?sum=1&des=2022RM4
  |archive-date=2022-10-09
  |url-status=live
  |access-date=2022-10-09}}</ref>

<ref name="MPC-object">{{cite web
  |title=2022 RM4 Orbit
  |work=Minor Planet Center
  |url=https://www.minorplanetcenter.net/db_search/show_object?object_id=2022+RM4
  |archive-url=https://archive.today/20221031141143/https://www.minorplanetcenter.net/db_search/show_object?object_id=2022+RM4
  |archive-date=2022-10-31
  |url-status=live
  |access-date=2022-10-31}}</ref>

<ref name="CA2022">{{cite web
  |title=Horizons Batch for 2022-11-01 Close Approach
  |publisher=[[Astronomy:JPL Horizons On-Line Ephemeris System|JPL Horizons]]
  |url=https://ssd.jpl.nasa.gov/horizons_batch.cgi?batch=1&COMMAND=%272022+RM4%27&START_TIME=%272022-11-01%2018:26%27&STOP_TIME=%272022-11-02%27&STEP_SIZE=%271%20day%27&QUANTITIES=%2720,39%27
  |archive-url=https://web.archive.org/web/20221009153250/https://ssd.jpl.nasa.gov/horizons_batch.cgi?batch=1&COMMAND=%272022+RM4%27&START_TIME=%272022-11-01%2018:28%27&STOP_TIME=%272022-11-02%27&STEP_SIZE=%271%20day%27&QUANTITIES=%2720,39%27
  |archive-date=2022-10-09
  |url-status=live
  |accessdate=2022-11-01}} RNG_3sigma = uncertainty range in km. (JPL#24/Soln.date: 2022-Nov-01 generates RNG_3sigma = 77 km)</ref>

<ref name="Archive221101">[https://web.archive.org/web/20221101151522/https://ssd.jpl.nasa.gov/horizons_batch.cgi?batch=1&COMMAND=%272022+RM4%27&START_TIME=%272022-11-01%2018:26%27&STOP_TIME=%272022-11-02%27&STEP_SIZE=%271%20day%27&QUANTITIES=%2720,39%27 Archive of JPL Horizons using JPL #24 solution date 2022-Nov-01]</ref>

<ref name="Mag2022">{{cite web
  |title=Magnitude near 2022-11-01 close approach
  |publisher=[[Astronomy:JPL Horizons On-Line Ephemeris System|JPL Horizons]]
  |url=https://ssd.jpl.nasa.gov/horizons_batch.cgi?batch=1&COMMAND=%272022+RM4%27&START_TIME=%272022-10-31%27&STOP_TIME=%272022-11-03%27&STEP_SIZE=%271%20hour%27&QUANTITIES=%272,9,20,23,29%27
  |accessdate=2022-10-09}}</ref>

<ref name=Earthsky>{{cite web
  |title=Large asteroid RM4 to pass closely November 1
  |url=https://earthsky.org/space/large-asteroid-to-pass-earth-on-november-1-2022
  |author=Kelly Kizer Whitt
  |publisher=Earthsky
  |date=2022-10-05
  |access-date=2022-10-09}}</ref>

<ref name=Goldstone>{{cite web
  |title=Goldstone Asteroid Schedule
  |url=https://echo.jpl.nasa.gov/asteroids/goldstone_asteroid_schedule.html
  |author=Dr. Lance A. M. Benner
  |publisher=NASA Asteroid Radar Research
  |access-date=2022-10-28}}</ref>

}} <!-- end of reflist-->

== External links ==
* [https://twitter.com/tony873004/status/1586608969614647296 Animation showing 2022RM4 approach from the Northern Hemisphere and exit the Southern Hemisphere] – Tony Dunn
* [https://www.virtualtelescope.eu/2022/10/15/potentially-hazardous-asteroid-2022-rm4-close-encounter-a-image-14-oct-2022/ Potentially Hazardous Asteroid 2022 RM4 close encounter: a image – 14 Oct. 2022]
* {{NeoDys|2022RM4}}
* {{ESA-SSA|2022RM4}}
* {{JPL small body|id=54303763 }}

__NOTOC__


{{DEFAULTSORT:2022 RM4}}
[[Category:Apollo asteroids|#]]

{{Sourceattribution|2022 RM4}}