HD 40307: Verskil tussen weergawes

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k Robot: standardiseer verwysingsjablone en voeg argiefskakels in.
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'''HD&nbsp;40307''' is ’n oranje [[Sterreklassifikasie|K-tipe]] [[hoofreeksster]] sowat 42 [[ligjare]] (12,83 [[parsek]]) van die [[Aarde]] af in die [[sterrebeeld]] [[Skilder (sterrebeeld)|Skilder]]. Sy massa is na raming effens minder as dié van die [[Son]]. Die ster het sover bekend ses planete wat om hom wentel. Drie planete is in 2008 ontdek en nog drie in 2012. Een van hulle, HD&nbsp;40307&nbsp;g, is ’n planeet soortgelyk aan die Aarde met ’n wentelperiode van sowat 200 dae en kan dalk vloeibare water op sy oppervlak hê. Nog navorsing is nodig om vas te stel of dit lewe kan huisves.<ref name="latimes-nov12">[http://www.latimes.com/news/science/sciencenow/la-sci-sn-earthlike-planet-water-atmosphere-red-light-20121107,0,2600859.story Possible Earth-like planet could hold water; scientists cautious], Amina Khan, Los Angeles Times, 7 November 2012. URL besoek op 8 November 2012.</ref><ref name="tuomi12">{{cite arXiv |last= Tuomi, Anglada-Escude, Gerlach, Jones, Reiners, Rivera, Vogt, Butler|first= Mikko, Guillem, Enrico, Hugh R. R., Ansgar, Eugenio J., Steven S., R. Paul|authorlink= |eprint= 1211.1617|title= Habitable-zone super-Earth candidate in a six-planet system around the K2.5V star HD 40307|class= astro-ph|year= 2012|version= v1|accessdate= 8 November 2012}}</ref><ref name="Space-20121107a">{{cite web |last=Wall |first=Mike |title='Super-Earth' Alien Planet May Be Habitable for Life |url=http://www.space.com/18393-alien-planet-super-earth-habitable-hd-40307g.html |date=7 November 2012 |publisher=Space.com |access-date=8 November 2012 |language=en |archive-url=https://web.archive.org/web/20200107051724/https://www.space.com/18393-alien-planet-super-earth-habitable-hd-40307g.html |archive-date=7 Januarie 2020 |url-status=live |df=dmy-all}}</ref><ref name="Space-20121107b">{{cite web |last=Tate |first=Karl |title=Super-Earth Planet: Potentially Habitable Alien World Explained (Infographic) |url=http://www.space.com/18390-super-earth-exoplanet-habitable-zone-infographic.html |date=7 November 2012 |publisher=Space.com |access-date=8 November 2012 |language=en |archive-url=https://web.archive.org/web/20190718124333/https://www.space.com/18390-super-earth-exoplanet-habitable-zone-infographic.html |archive-date=18 Julie 2019 |url-status=live |df=dmy-all}}</ref>
 
== Eienskappe ==
HD&nbsp;40307 is ’n K-tipe ster en straal dus oranje lig uit. Sy radius en massa is sowat ’n driekwart van die Son s’n. Sy temperatuur is net onder 5&nbsp;000 [[kelvin]]. Dit is relatief hoog vir ’n K-tipe ster en is naby dié van ’n G-tipe ster soos die Son.<ref>{{cite web |url=http://www.jb.man.ac.uk/distance/strobel/starprop/strpropd.htm |title=Properties of Stars |access-date=27 November 2008 |work=Astronomy Notes |publisher=Jodrell Bank Centre for Astrophysics |year=2007 |language=en |archive-url=https://web.archive.org/web/20080622012045/http://www.jb.man.ac.uk:80/distance/strobel/starprop/strpropd.htm |archive-date=22 Junie 2008 |url-status=dead |df=dmy-all}}</ref> Die sterrekundiges wat die planete om 40307 ontdek het, meen hul [[Metaal (astronomie)|metaalinhoud]] sal bepaal of hulle terrestriaal soos die Aarde of gasplanete soos [[Jupiter (planeet)|Jupiter]] en [[Saturnus]] is.<ref name="arXiv">{{cite journal|author= M. Mayor, S. Udry, C. Lovis, F. Pepe, D. Queloz, W. Benz, J.-L. Bertaux, F. Bouchy, C. Mordasini, D. Segransan|title=The HARPS search for southern extra-solar planets. XIII. A planetary system with 3 Super-Earths (4.2, 6.9, & 9.2 Earth masses)|journal=Submitted to Astronomy & Astrophysics|bibcode=2009A&A...493..639M|arxiv=0806.4587|doi=10.1051/0004-6361:200810451|year= 2009|volume= 493|issue= 2|pages= 639}}</ref>
 
Ondanks sy nabyheid aan die Aarde kan HD&nbsp;40307 nie met die blote oog gesien word nie.<ref>{{cite web |url=http://csep10.phys.utk.edu/astr162/lect/stars/magnitudes.html |title=Stellar Magnitudes |access-date=20 November 2008 |work=Astrophysics 162 Unit |publisher=University of Tennessee |year=2008 |language=en |archive-url=https://web.archive.org/web/20200512175551/http://csep10.phys.utk.edu/astr162/lect/stars/magnitudes.html |archive-date=12 Mei 2020 |url-status=live |df=dmy-all}}</ref>
 
== Planetêre stelsel ==
Vyf van HD&nbsp;40307 se planete wentel baie naby aan die ster,<ref name="tuomi12" /> met die verste een van hulle wat twee keer so naby is as [[Mercurius (planeet)|Mercurius]] aan die Son.<ref>{{cite web |title=Mercury Fact Sheet |url=http://nssdc.gsfc.nasa.gov/planetary/factsheet/mercuryfact.html |publisher=Nasa Goddard Space Flight Center |date=30 November 2007 |access-date=12 November 2008 |language=en |archive-url=https://web.archive.org/web/20200511174150/https://nssdc.gsfc.nasa.gov/planetary/factsheet/mercuryfact.html |archive-date=11 Mei 2020 |url-status=live |df=dmy-all}}</ref> Die heel verste planeet is omtrent so ver as [[Venus (planeet)|Venus]] van die Son en val binne die gebied waar water kan voorkom.<ref name="tuomi12" />
 
Die minimum massa van die planete wissel van drie tot tien keer dié van die Aarde.<ref name="tuomi12" />