4276 Clifford

{{Short description|Asteroid}}

{{Use dmy dates|date=October 2019}}

{{Infobox planet

| minorplanet = yes

| name = 4276 Clifford

| background = #FA8072

| discovery_ref =  

| discovered = 2 December 1981

| discoverer = E. Bowell

| discovery_site = Lowell Obs.

| mpc_name = (4276) Clifford

| alt_names = 1981 XA

| named_after = Clifford Cunningham {{small|(Canadian astronomer)}}

| mp_category = Mars-crosser{{·}}main belt

| orbit_ref =  

| epoch = 4 September 2017 (JD 2458000.5)

| uncertainty = 0

| observation_arc = 35.67 yr (13,027 days)

| aphelion = 2.4195 AU

| perihelion = 1.5994 AU

| semimajor = 2.0095 AU

| eccentricity = 0.2041

| period = 2.85 yr (1,040 days)

| mean_anomaly = 186.63°

| mean_motion = {{Deg2DMS|0.3460|sup=ms}} / day

| inclination = 21.033°

| asc_node = 76.881°

| arg_peri = 3.5494°

| dimensions = {{val|4.441|1.128}} km

| rotation =

| albedo = {{val|0.142|0.107}}

| spectral_type = SMASS = Cb

| abs_magnitude = 14.6

}}

4276 Clifford, provisional designation{{mp|1981 XA}} is an asteroid and sizable Mars-crosser from the innermost region of the asteroid belt, approximately 4.4 kilometers in diameter. It was discovered on 2 December 1981, by American astronomers Edward Bowell at Lowell Observatory in Flagstaff, United States. The asteroid was named in honor of astronomer and writer Clifford Cunningham.

Orbit and classification

Clifford is a member of the group of main-belt asteroids known as Mars-crosser asteroids, specifically, it is listed as an Outer-grazer.{{citation needed|date=June 2017}} It orbits the Sun at a distance of 1.6–2.4 AU once every 2 years and 10 months (1,040 days). Its orbit has an eccentricity of 0.20 and an inclination of 21° with respect to the ecliptic.

Physical characteristics

In the SMASS classification, Clifford is a Cb-type, which transitions from the carbonaceous C-type asteroids to the rare B-type asteroids.

According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Clifford measures 4.441 kilometers in diameter and its surface has an albedo of 0.142. As of 2017, no rotational lightcurve has been obtained of Clifford. Its rotation period and shape remain unknown.

Naming

This minor planet was named after Canadian astronomer and author Clifford Cunningham, who is best known for his 1988 published book Introduction to Asteroids and 5-volume history of asteroid studies published by Springer in 2016 and 2017. He received his Ph.D. in the history of astronomy in 2015. His astronomical work includes astrometry and photometry of minor planets. The approved naming citation was published by the Minor Planet Center on 10 April 1990 ({{small|M.P.C. 16248}}).

References

{{reflist|refs=

{{cite web

|type = 2017-06-05 last obs.

|title = JPL Small-Body Database Browser: 4276 Clifford (1981 XA)

|url = https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2004276

|publisher = Jet Propulsion Laboratory

|access-date = 15 June 2017}}

{{cite book

|title = Dictionary of Minor Planet Names – (4276) Clifford

|last = Schmadel | first = Lutz D.

|publisher = Springer Berlin Heidelberg

|page = 366

|date = 2007

|isbn = 978-3-540-00238-3

|doi = 10.1007/978-3-540-29925-7_4236 |chapter = (4276) Clifford }}

{{cite web

|title = 4276 Clifford (1981 XA)

|work = Minor Planet Center

|url = https://www.minorplanetcenter.net/db_search/show_object?object_id=4276

|access-date = 15 June 2017}}

{{cite web

|title = MPC/MPO/MPS Archive

|work = Minor Planet Center

|url = https://www.minorplanetcenter.net/iau/ECS/MPCArchive/MPCArchive_TBL.html

|access-date = 15 June 2017}}

{{cite web

|title = LCDB Data for (4276) Clifford

|publisher = Asteroid Lightcurve Database (LCDB)

|url = http://www.minorplanet.info/PHP/generateOneAsteroidInfo.php?AstInfo=4276%7CClifford

|access-date = 15 June 2017}}

{{Cite journal

|display-authors = 6

|first1 = C. R. |last1 = Nugent

|first2 = A. |last2 = Mainzer

|first3 = J. |last3 = Masiero

|first4 = J. |last4 = Bauer

|first5 = R. M. |last5 = Cutri

|first6 = T. |last6 = Grav

|first7 = E. |last7 = Kramer

|first8 = S. |last8 = Sonnett

|first9 = R. |last9 = Stevenson

|first10 = E. L. |last10 = Wright

|date = December 2015

|title = NEOWISE Reactivation Mission Year One: Preliminary Asteroid Diameters and Albedos

|url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2015ApJ...814..117N

|journal = The Astrophysical Journal

|volume = 814

|issue = 2

|page = 13

|bibcode = 2015ApJ...814..117N

|doi = 10.1088/0004-637X/814/2/117

|arxiv = 1509.02522

|s2cid = 9341381 |access-date= 15 June 2017}}

}}