GJ 3021

{{#if:\|{{{Typ}}}\|Doppelstern}}; {{#if:GJ 3021 / HD 1237\|GJ 3021 / HD 1237\|GJ 3021}}
	{{#ifexist:Media:\|[[Datei:\|310px\|zentriert\|alt=\|]]\|}}
	Vorlage:Sternkarte
	{{{Kartentext}}}
Beobachtungsdaten; Äquinoktium: J2000.0, Epoche: J2000.0
	Vorlage:AladinLite
Scheinbare Helligkeit <ref name="Simbad" />	6,58 mag
Bekannte Exoplaneten	1
	Position des Begleiters {{#if:\| ()}}
Winkelabstand	{{{Winkelabstand}}}
Positionswinkel	{{{Positionswinkel}}}
Astrometrie
Radialgeschwindigkeit	km/s
Parallaxe	(56,93 ± 0,02) mas<ref name="Simbad" />
Entfernung	{{#if:(57,26 ± 0,02)\|(57,26 ± 0,02) Lj{{#if:17,56 ± 0,01\|; (17,56 ± 0,01 pc)}}\|17,56 ± 0,01 pc}}
Absolute visuelle Helligkeit Mvis	mag
Absolute bolometrische Helligkeit Mbol	mag
	Veralteter Parameter "Absolut" !
Eigenbewegung
Rektaszensionsanteil:	(433,91 ± 0,04) mas/a
Deklinationsanteil:	(−56,32 ± 0,04) mas/a
Orbit
Periode
Große Halbachse	3,8" (68 AE)
Exzentrizität
Periastron
Apastron
Bahnneigung
Argument des Knotens
Epoche des Periastrons
Argument der Periapsis
Einzeldaten
Namen	{{#if:A\|A\|A}}; {{#if:B\|B\|B}}
	Beobachtungsdaten }}
B\|B}}	}}
B\|B}}	}}
B\|B}}	{{#if:\| mag}} }}
	Spektrum und Indices }}
A\|A}}	G6 V

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(G-Band) | {{#if:A|A|A}} | style="white-space:nowrap;" | {{#if:| mag}} |- | {{#if:B|B|B}} | style="white-space:nowrap;" | {{#if:| mag}} }} |- {{#if:| | rowspan=2 style="vertical-align:middle" | rel. Helligkeit
(J-Band) | {{#if:A|A|A}} | style="white-space:nowrap;" | {{#if:| mag}} |- | {{#if:B|B|B}} | style="white-space:nowrap;" | {{#if:| mag}} }} |- {{#if:| | rowspan=2 style="vertical-align:middle" | Absolute vis.
Helligkeit M_vis | {{#if:A|A|A}} | style="white-space:nowrap;" | {{#if:| mag}} |- | {{#if:B|B|B}} | style="white-space:nowrap;" | {{#if:| mag}} }} |- {{#if:| | rowspan=2 style="vertical-align:middle" | Absolute bol.
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| colspan="3" style="padding:0;" |

{{#if:|}}{{#if:|}}{{#if:|}}{{#if:-80° 9|}}{{#if:3021|}}{{#if:|}}{{#if:1237|}}{{#if:258219 |}}{{#if:9354/780/1|}}{{#if:1292 |}}{{#if: |}}{{#if: |}}{{#if: |}}{{#if: |}}{{#if: |}}{{#if: |}}{{#if: |}}{{#if: |}}{{#if: |}}{{#if:J00162-7951 |}}{{#if:NLTT 824 |{{#if:NLTT 824 ||{{#if:|}}}} }}

Katalog	{{#if:A\|A\|A}}	{{#if:B\|B\|B}}
Bayer-Bezeichnung	{{{Bayer}}}
Flamsteed-Bezeichnung	{{{Flamsteed}}}
Bonner Durchmusterung	BD {{{BD}}}
Córdoba-Durchmusterung	CD -80° 9
Gliese-Katalog	GJ 3021 {{#ifeq:{{#iferror:{{#expr: 1 * 3021}}\|???\|[9]}}\|???\|{{#if:\|\|}}\|{{#iferror:{{#expr: 1 * 3021}}\|???\|[10]}}}}
Bright-Star-Katalog	HR {{{HR}}} {{#ifeq:{{#iferror:{{#expr: 1 * {{{HR}}}}}\|???\|{{#ifexpr:{{{HR}}} <> (floor {{{HR}}}) or {{{HR}}} < 1 or {{{HR}}} > 9110 \|???\|[11]}}}}\|???\|{{#if:\|\|}}\|{{#iferror:{{#expr: 1 * {{{HR}}}}}\|???\|{{#ifexpr:{{{HR}}} <> (floor {{{HR}}}) or {{{HR}}} < 1 or {{{HR}}} > 9110 \|???\|[12]}}}}}}
Henry-Draper-Katalog	HD 1237 {{#ifeq:{{#iferror:{{#expr: 1 * 1237}}\|???\|{{#ifexpr:1237 <> (floor 1237) or 1237 < 1 or 1237 > 359083\|???\|{{#ifexpr: 1237 >= 1 and 1237 <= 272150\|[13]\|[14]}}}}}}\|???\|{{#if:\|\|}}\|{{#iferror:{{#expr: 1 * 1237}}\|???\|{{#ifexpr:1237 <> (floor 1237) or 1237 < 1 or 1237 > 359083\|???\|{{#ifexpr: 1237 >= 1 and 1237 <= 272150\|[15]\|[16]}}}}}}}}
SAO-Katalog	SAO 258219 {{#ifeq:{{#iferror:{{#expr: 1 * 258219}}\|???\|{{#ifexpr:258219 <> (floor 258219) or 258219 < 1 or 258219 > 258997 \|???\|[17]}}}}\|???\|{{#if:\|\|}}\|{{#iferror:{{#expr: 1 * 258219}}\|???\|{{#ifexpr:258219 <> (floor 258219) or 258219 < 1 or 258219 > 258997 \|???\|[18]}}}}}}
Tycho-Katalog	TYC {{#iferror:{{#expr: {{#ifeq:/Vorlage:Str replace \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+1}}}} \| \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+1}}}} }}{{#ifeq:/Vorlage:Str replace \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+2}}}} \| \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+2}}}} }}{{#ifeq:/Vorlage:Str replace \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+3}}}} \| \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+3}}}} }}}}\|{{#if:\|\|}}9354/780/1\|{{#ifeq:/Vorlage:Str replace \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+1}}}} \| \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+1}}}} }}-{{#ifeq:/Vorlage:Str replace \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+2}}}} \| \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+2}}}} }}-{{#ifeq:/Vorlage:Str replace \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+3}}}} \| \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+3}}}} }}[https://cdsarc.u-strasbg.fr/viz-bin/VizieR-5?-source=I/259&-out.all&-out.max=100&TYC1={{#ifeq:/Vorlage:Str replace \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+1}}}} \| \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+1}}}} }}&TYC2={{#ifeq:/Vorlage:Str replace \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+2}}}} \| \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+2}}}} }}&TYC3={{#ifeq:/Vorlage:Str replace \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+3}}}} \| \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+3}}}} }}]}}
Hipparcos-Katalog	HIP 1292 {{#ifeq:{{#iferror:{{#expr: 1 * 1292}}\|???\|{{#ifexpr:1292 <> (floor 1292) or 1292 < 1 or 1292 > 258997 \|???\|[19]}}}}\|???\|{{#if:\|\|}}\|{{#iferror:{{#expr: 1 * 1292}}\|???\|{{#ifexpr:1292 <> (floor 1292) or 1292 < 1 or 1292 > 258997 \|???\|[20]}}}}}}
New General Catalogue	NGC
Bonner Durchmusterung	BD	BD
Córdoba-Durchmusterung	CD	CD
Gliese-Katalog	GJ {{#ifeq:{{#iferror:{{#expr: 1 * {{{GJ1}}}}}\|???\|[21]}}\|???\|{{#if:\|\|}}\|{{#iferror:{{#expr: 1 * {{{GJ1}}}}}\|???\|[22]}}}}	GJ {{#ifeq:{{#iferror:{{#expr: 1 * {{{GJ2}}}}}\|???\|[23]}}\|???\|{{#if:\|\|}}\|{{#iferror:{{#expr: 1 * {{{GJ2}}}}}\|???\|[24]}}}}
Bright-Star-Katalog	HR {{#ifeq:{{#iferror:{{#expr: 1 * {{{HR1}}}}}\|???\|{{#ifexpr:{{{HR1}}} <> (floor {{{HR1}}}) or {{{HR1}}} < 1 or {{{HR1}}} > 9110 \|???\|[25]}}}}\|???\|{{#if:\|\|}}\|{{#iferror:{{#expr: 1 * {{{HR1}}}}}\|???\|{{#ifexpr:{{{HR1}}} <> (floor {{{HR1}}}) or {{{HR1}}} < 1 or {{{HR1}}} > 9110 \|???\|[26]}}}}}}	HR {{#ifeq:{{#iferror:{{#expr: 1 * {{{HR2}}}}}\|???\|{{#ifexpr:{{{HR2}}} <> (floor {{{HR2}}}) or {{{HR2}}} < 1 or {{{HR2}}} > 9110 \|???\|[27]}}}}\|???\|{{#if:\|\|}}\|{{#iferror:{{#expr: 1 * {{{HR2}}}}}\|???\|{{#ifexpr:{{{HR2}}} <> (floor {{{HR2}}}) or {{{HR2}}} < 1 or {{{HR2}}} > 9110 \|???\|[28]}}}}}}
Henry-Draper-Katalog	HD {{#ifeq:{{#iferror:{{#expr: 1 * {{{HD1}}}}}\|???\|{{#ifexpr:{{{HD1}}} <> (floor {{{HD1}}}) or {{{HD1}}} < 1 or {{{HD1}}} > 359083\|???\|{{#ifexpr: {{{HD1}}} >= 1 and {{{HD1}}} <= 272150\|[29]\|[30]}}}}}}\|???\|{{#if:\|\|}}\|{{#iferror:{{#expr: 1 * {{{HD1}}}}}\|???\|{{#ifexpr:{{{HD1}}} <> (floor {{{HD1}}}) or {{{HD1}}} < 1 or {{{HD1}}} > 359083\|???\|{{#ifexpr: {{{HD1}}} >= 1 and {{{HD1}}} <= 272150\|[31]\|[32]}}}}}}}}	HD {{#ifeq:{{#iferror:{{#expr: 1 * {{{HD2}}}}}\|???\|{{#ifexpr:{{{HD2}}} <> (floor {{{HD2}}}) or {{{HD2}}} < 1 or {{{HD2}}} > 359083\|???\|{{#ifexpr: {{{HD2}}} >= 1 and {{{HD2}}} <= 272150\|[33]\|[34]}}}}}}\|???\|{{#if:\|\|}}\|{{#iferror:{{#expr: 1 * {{{HD2}}}}}\|???\|{{#ifexpr:{{{HD2}}} <> (floor {{{HD2}}}) or {{{HD2}}} < 1 or {{{HD2}}} > 359083\|???\|{{#ifexpr: {{{HD2}}} >= 1 and {{{HD2}}} <= 272150\|[35]\|[36]}}}}}}}}
SAO-Katalog	SAO {{#ifeq:{{#iferror:{{#expr: 1 * {{{SAO1}}}}}\|???\|{{#ifexpr:{{{SAO1}}} <> (floor {{{SAO1}}}) or {{{SAO1}}} < 1 or {{{SAO1}}} > 258997 \|???\|[37]}}}}\|???\|{{#if:\|\|}}\|{{#iferror:{{#expr: 1 * {{{SAO1}}}}}\|???\|{{#ifexpr:{{{SAO1}}} <> (floor {{{SAO1}}}) or {{{SAO1}}} < 1 or {{{SAO1}}} > 258997 \|???\|[38]}}}}}}	SAO {{#ifeq:{{#iferror:{{#expr: 1 * {{{SAO2}}}}}\|???\|{{#ifexpr:{{{SAO2}}} <> (floor {{{SAO2}}}) or {{{SAO2}}} < 1 or {{{SAO2}}} > 258997 \|???\|[39]}}}}\|???\|{{#if:\|\|}}\|{{#iferror:{{#expr: 1 * {{{SAO2}}}}}\|???\|{{#ifexpr:{{{SAO2}}} <> (floor {{{SAO2}}}) or {{{SAO2}}} < 1 or {{{SAO2}}} > 258997 \|???\|[40]}}}}}}
Tycho-Katalog	TYC Vorlage:Str replace[https://cdsarc.u-strasbg.fr/viz-bin/VizieR-5?-source=I/259&-out.all&-out.max=100&TYC1={{#ifeq:/Vorlage:Str replace \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+1}}}} \| \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+1}}}} }}&TYC2={{#ifeq:/Vorlage:Str replace \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+2}}}} \| \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+2}}}} }}&TYC3={{#ifeq:/Vorlage:Str replace \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+3}}}} \| \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+3}}}} }}]	TYC Vorlage:Str replace[https://cdsarc.u-strasbg.fr/viz-bin/VizieR-5?-source=I/259&-out.all&-out.max=100&TYC1={{#ifeq:/Vorlage:Str replace \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+1}}}} \| \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+1}}}} }}&TYC2={{#ifeq:/Vorlage:Str replace \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+2}}}} \| \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+2}}}} }}&TYC3={{#ifeq:/Vorlage:Str replace \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+3}}}} \| \|{{#titleparts:/Vorlage:Str replace\|1\|{{#expr:1+3}}}} }}]
Hipparcos-Katalog	HIP	HIP
WDS-Katalog	WDS J00162-7951
Weitere Bezeichnungen:	NLTT 824

}}

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}}}}

GJ 3021 (auch bekannt als HD 1237) ist ein Stern im Gliese-Jahreiß-Katalog, der wegen seiner Ähnlichkeit zur Sonne und der Existenz eines Exoplaneten von besonderer wissenschaftlicher Bedeutung ist. Der Stern ist vom Spektraltyp G6 V<ref>{{#invoke:Vorlage:Literatur|f}}{{#if:

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  }}</ref> und ist im Sternbild Kleine Wasserschlange zu finden. Die Oberflächentemperatur des Sterns beträgt circa 5600 Kelvin, seine Masse beträgt 90 % der Sonnenmasse. Über das Alter des seit der Entdeckung des Exoplaneten sehr genau untersuchten Sternes gibt es verschiedene Ansichten, die Beurteilungen schwanken je nach Bestimmungsmethode zwischen 150 Millionen und 8,8 Milliarden Jahren<ref>{{#invoke:Vorlage:Literatur|f}}{{#if: 
       | {{#if: Vorlage:Cite book/ParamBool
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  }}{{#invoke:TemplatePar|check
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  }}Vorlage:Cite book/URL{{#if:  | Vorlage:Cite book/Meldung }}{{#if:        | Vorlage:Cite book/Meldung }}{{#if: Astronomy and Astrophysics
     || Vorlage:Cite book/Meldung
  }}{{#if: Vorlage:Cite book/ParamBool
        | Vorlage:Cite book/Meldung
  }}{{#if: Vorlage:Cite book/ParamBool
     | Vorlage:Cite book/Meldung
  }}{{#if: Vorlage:Cite book/ParamBool
     | Vorlage:Cite book/Meldung
  }}{{#if: Vorlage:Cite book/ParamBool
     | Vorlage:Cite book/Meldung
  }}{{#if: Vorlage:Cite book/ParamBool
       | Vorlage:Cite book/Meldung
  }}{{#if: Vorlage:Cite book/ParamBool
     | Vorlage:Cite book/Meldung
  }}Vorlage:Cite book/Meldung2{{#ifexpr: 0{{#ifeq:^^|^^||+1}}{{#ifeq:^^|^^||+1}}{{#ifeq:Saffe, C. et al.|^^||+1}}{{#ifeq:^^|^^||+1}} > 1
    | Vorlage:Cite book/Meldung
  }}</ref>. Der Stern ist von der Sonne etwa 57,5 Lichtjahre (17,6 Parsec) entfernt.

Der Begleiter

Der den Stern umkreisende Exoplanet wird GJ 3021 b genannt und ist wahrscheinlich ein dem Jupiter ähnlicher Gasplanet.

Einzelnachweise