The following is a list of stars with resolved images, that is, stars whose images have been resolved beyond a point source.[clarification needed] Aside from the Sun, observed from Earth, stars are exceedingly small in apparent size, requiring the use of special high-resolution equipment and techniques to image. For example, Betelgeuse, the first star other than the Sun to be directly imaged, has an angular diameter of only 50 milliarcseconds (mas).[1]
This list is incomplete; you can help by adding missing items. (December 2017) |
Star | Image | Diameter | Distance (ly) |
First imager | Year | Notes | |
---|---|---|---|---|---|---|---|
Angular (mas) | Geometric (Sun = 1) | ||||||
Sun | 2000000 | 1 | 0.0000158 | Louis Fizeau and Léon Foucault[2] | 1845 | ||
Altair α Aql |
3.2 | 1.66±0.01 (polar) 2.02±0.01 (equator) |
16.77±0.08 | CHARA array – MIRC[3] | 2006 | ||
Rasalhague α Oph A |
1.62±0.03 | 2.39±0.01 (polar) 2.87±0.02 (equator) |
48.6±0.8 | CHARA array – MIRC[4] | 2006 | ||
Alderamin α Cep |
1.35±0.02 (polar) 1.75±0.03 (equator) |
2.20±0.04 (polar) 2.74±0.04 (equator) |
48.8±0.36 | CHARA array – MIRC[4] | 2006 | ||
Caph β Cas |
1.70±0.04 | 3.1±0.1 (polar) 3.8±0.1 (equator) |
54.7±0.3 | CHARA array – MIRC[5] | 2007 | ||
Regulus α Leo Aa |
1.24±0.02 | 3.2±0.1 (polar) 4.2±0.1 (equator) |
79.3±0.7 | CHARA array – MIRC[5] | 2008 | ||
Algol β Per Aa1 |
|
0.88±0.05 | 4.13 | 93±2 | CHARA array – MIRC[6] | 2006 | stationary object in the animation |
β Per Aa2 | 1.12±0.07 | 3 | orbiting object in the animation | ||||
β Per Ab | 0.56±0.10 | 0.9 | Observed radius of Algol Ab is an instrumental artifact, caused by bandwidth smearing. Actual radius is 1.73 ± 0.33 R☉. | ||||
Alkaid η UMa |
0.834±0.060 | 2.86±0.21 | 103.9±0.8 | CHARA array[7] | 2012 | ||
Markab α Peg |
1.052±0.066 | 4.62±0.29 | 133±1 | CHARA array[7] | 2012 | ||
Elnath β Tau |
1.09±0.076 | 4.82±0.34 | 134±2 | CHARA array[7] | 2012 | ||
ζ And Aa | 2.502±0.008 | 15.0±0.8 (polar) | 189±3 | CFHT[8][9] | 1996 | First direct imaging of starspots on a star outside the Solar System. | |
R Dor | 57±5 | 370±50 | 204±9 | New Technology Telescope[10] | 1993 | 2nd largest known star by apparent diameter in Earth's sky, after the Sun. | |
Mira ο Cet A |
50 | up to 700 | 420 | Hubble – FOC[11] | 1997[citation needed] | ||
T Lep | 5.8 15 for molecular layer |
100 | 500 | Very Large Telescope – VLTI[12]/AMBER[13] | 2009[citation needed] | ||
π1 Gru | 18.37[citation needed] | 694 | 530 | Very Large Telescope – VLTI/PIONIER[14] | 2017[citation needed] | First directly observed granulation patterns on a star's surface outside the Solar System. | |
Antares α Sco A |
41.3±0.1 | 700 | 620 | Very Large Telescope – VLTI/AMBER[15] | 2017[citation needed] | ||
Betelgeuse α Ori |
50 | 630 | 643±146 | Hubble – GHRS[1] | 1995 | First star with a resolved image outside the Solar System. | |
Sheliak β Lyr Aa |
0.46 | 6 | 960±50 | CHARA array – MIRC[16] | 2007 | Both Aa1 and Aa2 are visible in the animation. | |
θ1 Ori C | 0.2 | 10.6±1.5 | 1400 | Very Large Telescope – AMBER[17] | 2009 | In the image, the right inset is θ1 Ori C and the left inset is θ1 Ori F. | |
θ1 Ori F | Very Large Telescope – VLTI/GRAVITY[18] | 2016[citation needed] | |||||
Almaaz ε Aur A |
2.27 | 3.7±0.7 | ca. 2000 | CHARA array – MIRC[19] | 2009 | Supergiant with an eclipsing companion surrounded by a massive, opaque debris disk | |
RW Cephei | 2.45 | 900–1760 | 11000+4600 −2600–22000+5200 −3300 |
CHARA array – MIRC-X and MYSTIC[20] | 2022 | Hypergiant star currently undergoing a great dimming event | |
HR 5171 Aa | 4.1±0.8 | 1575±400 | 11740±1630 | Very Large Telescope – VLTI/PIONIER[21] | 2014 | Eclipsing and potential contact binary yellow hypergiant |