G 9-38

{{Short description|Star in the constellation Cancer}}

{{Distinguish|G 29-38}}

{{Sky|08|58|15.194|+|19|45|47.08|16.62}}

{{Starbox begin

|name=GJ 1116}}

{{Starbox image

| image = 320px

| caption = An ultraviolet band light curve showing several flares on EI Cancri, adapted from Pettersen (1985)

}}

{{Starbox observe

|epoch=J2000

|constell=Cancer

|ra={{RA|08|58|15.194}}{{cite journal |bibcode=2003yCat.2246....0C |title=VizieR Online Data Catalog: 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003) |journal=CDS/ADC Collection of Electronic Catalogues |pages=II/246 |volume=2246 |last1=Cutri |first1=Roc M. |last2=Skrutskie |first2=Michael F. |last3=Van Dyk |first3=Schuyler D. |last4=Beichman |first4=Charles A. |last5=Carpenter |first5=John M. |last6=Chester |first6=Thomas |last7=Cambresy |first7=Laurent |last8=Evans |first8=Tracey E. |last9=Fowler |first9=John W. |last10=Gizis |first10=John E. |last11=Howard |first11=Elizabeth V. |last12=Huchra |first12=John P. |last13=Jarrett |first13=Thomas H. |last14=Kopan |first14=Eugene L. |last15=Kirkpatrick |first15=J. Davy |last16=Light |first16=Robert M. |last17=Marsh |first17=Kenneth A. |last18=McCallon |first18=Howard L. |last19=Schneider |first19=Stephen E. |last20=Stiening |first20=Rae |last21=Sykes |first21=Matthew J. |last22=Weinberg |first22=Martin D. |last23=Wheaton |first23=William A. |last24=Wheelock |first24=Sherry L. |last25=Zacarias |first25=N. |year=2003 |url=http://vizier.u-strasbg.fr/viz-bin/VizieR?-source=II/246 }}

|dec={{DEC|+19|45|47.08}}

|appmag_v=13.720{{cite journal|author1=Zacharias, N.|title=The fourth US Naval Observatory CCD Astrograph Catalog (UCAC4)|journal=VizieR On-line Data Catalog|date=2012|bibcode=2012yCat.1322....0Z}}

}}

{{Starbox character

|class=M8Ve+M7V

}}

{{Starbox astrometry

|component1 = G 9-38 A

|radial_v=13 ± 5

|prop_mo_ra={{val|-767.060|0.122}}

|prop_mo_dec={{val|-100.176|0.083}}

|parallax=194.1443

|p_error=0.1228

|parallax_footnote={{Cite Gaia EDR3|660597997696173440}}

|absmag_v=

|component2 = G 9-38 B

|radial_v2=

|prop_mo_ra2={{val|-937.133|0.190}}

|prop_mo_dec2={{val|-34.559|0.138}}

|parallax2=196.2619

|p_error2=0.1976

|parallax_footnote2={{Cite Gaia EDR3|660597997697274752}}

|absmag_v2=

}}

{{Starbox orbit

| reference =

| primary = G 9-38A

| name = G 9-38B

| period = 360

| period_unitless =

| axis =

| axis_unitless = 33 AU

| eccentricity =

| inclination =

| node =

| periastron =

| periarg =

| periarg_primary =

| k1 =

| k2 =

}}

{{Starbox detail

|source={{citation|arxiv=1112.4567|title=Metallicity and Temperature Indicators in M dwarf K band Spectra: Testing New & Updated Calibrations With Observations of 133 Solar Neighborhood M dwarfs

|year=2011|doi=10.1088/0004-637X/748/2/93

|last1=Rojas-Ayala

|first1=Bárbara

|last2=Covey

|first2=Kevin R.

|last3=Muirhead

|first3=Philip S.

|last4=Lloyd

|first4=James P.

|journal=The Astrophysical Journal

|volume=748

|issue=2

|page=93

|bibcode=2012ApJ...748...93R

|s2cid=41902340

}}[http://www.gdnordley.com/_files/Nearby%20Star%20Summary.html Nearby Star Summary Table]

|component1=G 9-38A

|mass=0.12

|luminosity_bolometric = 0.000965

|temperature=2896{{±|18}}

|gravity=

|metal_fe=-0.12(unreliable)

|age_gyr=

|component2=G 9-38B

|mass2=0.10

|luminosity_bolometric2 = 0.000992

|temperature2=

|gravity2=

|metal_fe2=

|age_gyr2=

}}

{{Starbox catalog

|names={{odlist

|G=9-38

|G2=47-14

|G3=41-11

|GJ=1116

|V=EI Cnc

|LDS=3836

|LP=426-40

|LTT=12343

|PLX=2144.03

|WDS=J08582+1945AB

|GSC=01397-01138

|2MASS=J08581519+1945470

}}

|component1=A

|names1={{Odlist

|LHS=2076

|NLTT=20638

|Gaia DR2=660597997696173440

}}

|component2=B

|names2={{Odlist

|LHS=2077

|NLTT=20637

|Gaia DR2=660597997697274752

}}

}}

{{Starbox reference

|Simbad=GJ+1116

|sn=The system

|Simbad2=GJ+1116+A

|sn2=A

|Simbad3=GJ+1116+B

|sn3=B

}}

{{Starbox image

|image={{Location map|100x100|AlternativeMap=Cancer_constellation_map.svg

|alt=G 9-38 is located in the constellation Cancer

|caption=Location of G 9-38 in the constellation Cancer|border=infobox|mark=Red_pog.png|width=320

|label=G 9-38

|position=left

|lat=49.4

|long=39.4

}}|caption=

}}

{{Starbox end}}

G 9-38, also known as EI Cancri and GJ 1116, is a binary star system consisting of two M-type stars.[http://vizier.u-strasbg.fr/viz-bin/VizieR-S?GJ%201116%20B Vizier query: Name=G* 1116], Centre de Données astronomiques de Strasbourg, accessed 30 December 2012. At 16.7 light-years from the Sun, the system is relatively nearby.[http://phl.upr.edu/projects/nearby-stars-catalog Nearby Stars Catalog (NSC)] {{Webarchive|url=https://web.archive.org/web/20210227120810/http://phl.upr.edu/projects/nearby-stars-catalog |date=2021-02-27 }}, Planetary Habitability Laboratory, University of Puerto Rico at Arecibo accessed 31 December 2012.

In 1985, Bjørn Ragnvald Pettersen announced his discovery that the star shows very high stellar flare activity, with an average of five flares per hour. It was given its variable star designation, EI Cancri, in 1987.

In 2015, the search for third star in the system has yielded inconclusive results.{{citation|arxiv=1501.05012|title=A 3D Search for Companions to 12 Nearby M-Dwarfs

|year=2015|doi=10.1088/0004-6256/149/3/106

|last1=Davison

|first1=Cassy L.

|last2=White

|first2=R. J.

|last3=Henry

|first3=T. J.

|last4=Riedel

|first4=A. R.

|last5=Jao

|first5=W-C.

|last6=Bailey Iii

|first6=J. I.

|last7=Quinn

|first7=S. N.

|last8=Cantrell

|first8=J. R.

|last9=Subasavage

|first9=J. P.

|last10=Winters

|first10=J. G.

|journal=The Astronomical Journal

|volume=149

|issue=3

|page=106

|bibcode=2015AJ....149..106D

|s2cid=9719725

}}