Stars Fornax

lacaille gave bayer designations 27 stars named alpha omega fornacis, labelling 2 stars 3.5 degrees apart gamma, 3 stars eta, 2 stars iota, 2 lambda , 3 chi. phi fornacis added gould, , theta , omicron dropped gould , baily respectively. upsilon, too, later found 2 stars , designated such. overall, there 59 stars within constellation s borders brighter or equal apparent magnitude 6.5. however, there no stars brighter fourth magnitude.

the 3 brightest stars form flattish triangle, alpha , nu fornacis marking eastern , western points , beta fornacis marking shallow southern apex. designated 12 eridani john flamsteed, alpha fornacis named lacaille brightest star in new constellation. binary star can resolved small amateur telescopes. apparent magnitude of 3.91, primary yellow-white subgiant 1.21 times massive sun has begun cool , expand after exhausting core hydrogen, having swollen 1.9 times sun s radius. of magnitude 6.5, secondary star 0.78 times massive sun. has been identified blue straggler, , has either accumulated material from, or merged with, third star in past. strong source of x-rays. pair 46.4 ± 0.3 light-years distant earth.

beta fornacis yellow-hued giant star of spectral type g8iiib of magnitude 4.5 has cooled , swelled 11 times sun s diameter, 169 ± 6 light-years earth. red clump giant, means has undergone helium flash , generating energy through fusion of helium @ core.

nu fornacis 370 ± 10 light-years distant earth. blue giant star of spectral type b9.5iiispsi 3.65 ± 0.18 times massive , around 245 times luminous sun, 3.2 ± 0.4 times diameter. varies in luminosity on period of 1.89 days—the same rotational period. because of differences in abundances of metals in atmosphere; belongs class of star known alpha canum venaticorum variable.

shining apparent magnitude of 5.89, epsilon fornacis binary star system located 105 ± 1 light-years distant earth. component stars orbit each other every 37 years. primary star around 12 billion years old , has cooled , expanded 2.53 times diameter of sun, while having 91% of mass. omega fornacis binary star system composed of blue main-sequence star of spectral type b9.5v , magnitude 4.96, , white main sequence star of spectral type a7v , magnitude 7.88.

lp 944-20 brown dwarf of spectral type m9 has around 7% mass of sun. approximately 21 light-years distant earth, faint object apparent magnitude of 18.69. observations published in 2007 showed atmosphere of lp 944-20 contains lithium , has dusty clouds. smaller , less luminous still 2mass 0243-2453, t-type brown dwarf of spectral type t6. surface temperature of 1040–1100 k, has 2.4–4.1% mass of sun, diameter 9.2 10.6% of of sun, , age of 0.4–1.7 billion years.

six star systems in fornax have been found have planets:

lambda fornacis star 1.2 times massive sun planet massive neptune, discovered doppler spectroscopy in 2009. planet has orbit of around 17.24 days.
hd 20868 orange dwarf mass around 78% of sun, 151 ± 10 light-years away earth. found have orbiting planet approximately double mass of jupiter period of 380 days.
wasp-72 star around 1.4 times massive has begun cool , expand off main sequence, reaching double sun s diameter. has planet around massive jupiter orbiting every 2.2 days.
hd 20781 , hd 20782 pair of sunlike yellow main sequence stars orbit each other. each has been found have planets.




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