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List of stars in Ursa Major
List of stars in Ursa Major
List of stars in Ursa Major
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This is the list of notable stars in the constellation Ursa Major, sorted by decreasing brightness.

Name B F Var HD HIP RA Dec vis.
mag. 		abs.
mag. 		Dist. (ly) Sp. class Notes
Alioth ε 77 112185 62956 12h 54m 01.63s +55° 57′ 35.4″ 1.77 −0.21 81 A0p Alioth; brown dwarf companion?; α² CVn variable
Dubhe α 50 95689 54061 11h 03m 43.84s +61° 45′ 04.0″ 1.79 −1.08 124 K0III + F0V Dubhe, Dubh, Dubb, Thahr al Dub al Akbar, Ak
Alkaid η 85 120315 67301 13h 47m 32.55s +49° 18′ 47.9″ 1.86 −0.60 101 B3V SB Benetnasch, Alkaid, Elkeid
Mizar A ζ1 79 116656 65378 13h 23m 55.54s +54° 55′ 31.3″ 2.23 0.32 83 A2V SB spectroscopic binary, the Mizar pair also form a naked eye double with Alcor
Merak β 48 95418 53910 11h 01m 50.39s +56° 22′ 56.4″ 2.37 0.41 79 A1V Merak, Mirak
Phecda γ 64 103287 58001 11h 53m 49.74s +53° 41′ 41.0″ 2.44 0.36 84 A0V SB Phad, Phecda, Phegda, Phekha, Phacd
ψ UMa ψ 52 96833 54539 11h 09m 39.86s +44° 29′ 54.8″ 3.01 −0.27 147 K1III Ta Tsun
μ UMa μ 34 89758 50801 10h 22m 19.80s +41° 29′ 58.0″ 3.06 −1.35 249 M0III SB Tania Australis, Alkafzah Australis; semiregular variable
θ UMa θ 25 82328 46853 09h 32m 52.33s +51° 40′ 43.0″ 3.12 2.52 44 F6IV Al Haud, Sarir, Sarir Bonet
ι UMa ι 9 76644 44127 08h 59m 12.84s +48° 02′ 32.5″ 3.14 2.29 48 A7IV Talitha, Dnoces, Alphikra Borealis; quadruple star
Megrez δ 69 106591 59774 12h 15m 25.45s +57° 01′ 57.4″ 3.31 1.33 81 A3Vvar Megrez, Kaffa
ο UMa ο 1 71369 41704 08h 30m 16.03s +60° 43′ 06.4″ 3.35 −0.40 184 G4II-III Muscida, has a planet (b)
λ UMa λ 33 89021 50372 10h 17m 05.93s +42° 54′ 52.1″ 3.45 0.38 134 A2IV Tania Borealis, Alkafzah Borealis
ν UMa ν 54 98262 55219 11h 18m 28.76s +33° 05′ 39.3″ 3.49 −2.07 421 K3III SB Alula Borealis
κ UMa κ 12 77327 44471 09h 03m 37.56s +47° 09′ 24.0″ 3.56 −1.99 423 A1Vn Alkaphrah, Al Kaprah, Talitha Australis, Alphikra Australis
23 UMa h 23 81937 46733 09h 31m 31.57s +63° 03′ 42.5″ 3.65 1.83 75 F0IV
χ UMa χ 63 102224 57399 11h 46m 03.13s +47° 46′ 45.6″ 3.72 −0.20 196 K0III Taiyangshou, Alkafzah, Alkaphrah, El Koprah
υ UMa υ 29 84999 48319 09h 50m 59.69s +59° 02′ 20.8″ 3.78 1.04 115 F0IV δ Sct variable
Mizar B ζ2 79 65378 116657 13h 23m 56.33s +54° 55′ 18.56″ 3.88 1.96 83 A3m spectroscopic binary, the Mizar pair also form a naked eye double with Alcor
Alcor g 80 116842 65477 13h 25m 13.54s +54° 59′ 16.7″ 3.99 2.00 82 A5Vn Saidak, Suha, Arundhati; naked-eye double star with Mizar
ξ UMa A ξ 53 98230 55203 11h 18m 11.24s +31° 31′ 50.8″ 4.26 4.18 27.3 G0V Alula Australis; binary star; RS CVn variable
15 UMa f 15 78209 44901 09h 08m 52.39s +51° 36′ 17.0″ 4.46 2.13 96 Am
26 UMa 26 82621 47006 09h 34m 49.49s +52° 03′ 05.6″ 4.47 −0.10 267 A2V
24 UMa d 24 DK 82210 46977 09h 34m 28.97s +69° 49′ 48.6″ 4.54 1.99 106 G4III-IV DK UMa; RS CVn variable
φ UMa φ 30 85235 48402 09h 52m 06.36s +54° 03′ 51.4″ 4.60 −1.08 436 A3IV
ω UMa ω 45 94334 53295 10h 53m 58.71s +43° 11′ 24.1″ 4.61 0.10 267 A1Vs
π2 UMa π2 4 73108 42527 08h 40m 12.90s +64° 19′ 40.3″ 4.62 0.15 252 K2III has a planet (b)
τ UMa τ 14 78362 45075 09h 10m 54.93s +63° 30′ 49.6″ 4.66 1.81 122 Am
83 UMa 83 IQ 119228 66738 13h 40m 44.29s +54° 40′ 54.0″ 4.69 −1.50 549 M2IIIvar IQ UMa
HD 91312 91312 51658 10h 33m 14.00s +40° 25′ 31.9″ 4.72 2.04 112 A7IV
ξ UMa B ξ 53 98231 11h 18m 11.00s +31° 31′ 45.0″ 4.73 5.16 G2V component of the ξ UMa system
ρ UMa ρ 8 76827 44390 09h 02m 32.73s +67° 37′ 46.5″ 4.74 0.01 287 M3III
55 UMa 55 98353 55266 11h 19m 07.94s +38° 11′ 08.6″ 4.80 1.01 183 A2V
σ2 UMa σ2 13 78154 45038 09h 10m 23.53s +67° 08′ 03.3″ 4.80 3.25 67 F7IV-V
36 UMa 36 90839 51459 10h 30m 37.76s +55° 58′ 50.2″ 4.82 4.28 42 F8V
18 UMa e 18 DD 79439 45493 09h 16m 11.28s +54° 01′ 18.2″ 4.83 2.00 118 A5V DD UMa; δ Sct variable
78 UMa 78 113139 63503 13h 00m 43.59s +56° 21′ 58.8″ 4.93 2.94 81 F2V
ET UMa ET 89822 50933 10h 24m 07.86s +65° 33′ 59.3″ 4.94 0.12 301 A0sp... α² CVn variable
92523 52425 10h 43m 04.04s +69° 04′ 34.5″ 4.99 −0.57 426 K3III
46 UMa 46 94600 53426 10h 55m 44.46s +33° 30′ 25.2″ 5.03 0.64 245 K1III
56 UMa 56 98839 55560 11h 22m 49.61s +43° 28′ 57.9″ 5.03 −0.90 492 G8II
47 UMa 47 95128 53721 10h 59m 28.22s +40° 25′ 48.4″ 5.03 4.29 46 G0V Chalawan,[1] has three planets (b, c & d)
49 UMa 49 95310 53838 11h 00m 50.48s +39° 12′ 43.7″ 5.06 −0.40 403 Am
15 LMi (15) 84737 48113 09h 48m 35.18s +46° 01′ 16.4″ 5.08 3.75 60 G2V
44 UMa 44 94247 53261 10h 53m 34.52s +54° 35′ 06.5″ 5.11 −1.46 676 K3III
38 UMa 38 92424 52353 10h 41m 56.78s +65° 42′ 59.3″ 5.12 0.94 224 K2IIIvar
σ1 UMa σ1 11 77800 44857 09h 08m 23.53s +66° 52′ 24.0″ 5.14 −0.77 498 K5III
27 UMa 27 83506 47654 09h 42m 57.24s +72° 15′ 09.7″ 5.15 −0.51 442 K0III
37 UMa 37 91480 51814 10h 35m 09.62s +57° 04′ 57.2″ 5.16 3.05 86 F1V
16 UMa c 16 79028 45333 09h 14m 20.55s +61° 25′ 24.2″ 5.18 3.72 64 F9V
92787 52469 10h 43m 33.12s +46° 12′ 14.5″ 5.18 2.42 116 F5III
44 Lyn (44) CS 84335 47965 09h 46m 31.66s +57° 07′ 40.8″ 5.20 −1.07 556 M3III
67 UMa 67 DP 104513 58684 12h 02m 07.06s +43° 02′ 43.7″ 5.22 2.57 111 A7m DP UMa; δ Sct variable
31 UMa 31 SY 85795 48682 09h 55m 43.01s +49° 49′ 11.3″ 5.27 1.10 223 A3III SY UMa
102328 57477 11h 46m 55.61s +55° 37′ 41.8″ 5.27 1.26 206 K3III
17 UMa 17 79354 45455 09h 15m 49.81s +56° 44′ 29.3″ 5.28 −1.32 681 K5III
57 UMa 57 99787 56034 11h 29m 04.16s +39° 20′ 13.0″ 5.30 1.26 209 A2V
61 UMa 61 101501 56997 11h 41m 03.03s +34° 12′ 09.2″ 5.31 5.41 31 G8Vvar
55 Cam (55) 67447 40215 08h 12m 48.79s +68° 28′ 26.6″ 5.34 −2.22 1062 G8II
74 UMa 74 108844 60978 12h 29m 57.40s +58° 24′ 19.9″ 5.37 0.74 274 A5e...
117376 65728 13h 28m 27.18s +59° 56′ 44.5″ 5.40 1.10 236 A1Vn
41 Lyn (41) 81688 46471 09h 28m 39.99s +45° 36′ 06.5″ 5.41 0.68 288 K0III-IV Intercrus,[1] has a planet (b)
100203 56290 11h 32m 20.76s +61° 04′ 57.9″ 5.46 3.26 90 F6V
82 UMa 82 119024 66634 13h 39m 30.58s +52° 55′ 15.9″ 5.46 1.88 169 A3Vn
2 UMa A 2 72037 42080 08h 34m 36.19s +65° 08′ 43.0″ 5.47 2.04 158 A2m
95212 53781 11h 00m 14.70s +45° 31′ 34.6″ 5.47 −1.69 881 K5III
77601 44613 09h 05m 24.11s +48° 31′ 49.3″ 5.48 0.34 348 F6II-III
86378 49005 09h 59m 51.72s +56° 48′ 42.8″ 5.50 −0.47 510 K5III
70 UMa 70 107465 60212 12h 20m 50.83s +57° 51′ 51.4″ 5.54 −1.12 701 K5III
92095 52136 10h 39m 05.74s +53° 40′ 06.6″ 5.55 −0.44 514 K3III
59 UMa 59 101107 56770 11h 38m 20.69s +43° 37′ 31.8″ 5.56 2.26 149 F2II-III
6 UMa 6 75958 43903 08h 56m 37.49s +64° 36′ 14.5″ 5.57 0.69 308 G6III
42 UMa 42 93875 53064 10h 51m 23.76s +59° 19′ 12.9″ 5.57 1.04 263 K2III
104438 58654 12h 01m 39.53s +36° 02′ 32.2″ 5.59 0.36 362 K0III
81 UMa 81 118214 66198 13h 34m 07.33s +55° 20′ 54.4″ 5.60 0.95 306[2] A0V
π1 UMa π1 3 72905 42438 08h 39m 11.74s +65° 01′ 14.5″ 5.63 4.86 47 G1.5Vb Muscida; BY Draconis variable
100615 56510 11h 35m 04.90s +54° 47′ 07.4″ 5.63 0.13 411 K0III
73017 42372 08h 38m 22.26s +53° 24′ 05.7″ 5.66 1.32 241 G8IV
43 UMa 43 93859 53043 10h 51m 11.08s +56° 34′ 56.1″ 5.66 0.51 350 K2III
73 UMa 73 108502 60795 12h 27m 35.13s +55° 42′ 45.9″ 5.68 0.03 439 M2III
84 UMa 84 CR 120198 67231 13h 46m 35.68s +54° 25′ 57.7″ 5.68 1.00 282 B9p EuCr CR UMa; α² CVn variable
86 UMa 86 121409 67848 13h 53m 51.04s +53° 43′ 43.3″ 5.70 0.03 444 A0V
87141 49363 10h 04m 36.35s +53° 53′ 30.2″ 5.71 2.34 154 F5V
CO UMa CO 96813 54522 11h 09m 19.11s +36° 18′ 34.0″ 5.71 0.39 379 M3.5III
5 UMa b 5 75486 43644 08h 53m 22.57s +61° 57′ 44.0″ 5.72 1.01 285 F2III
83489 47594 09h 42m 14.93s +69° 14′ 15.7″ 5.72 −0.11 479 G9III:
57 Cam (57) OS 69148 40772 08h 19m 17.18s +62° 30′ 25.7″ 5.73 −0.07 470 G8III OS UMa, RS CVn variable
HD 89744 89744 50786 10h 22m 10.0s +41° 13′ 46″ 5.74 2.78 130 F7V has two planets (b and c)
47 LMi (47) 94497 53377 10h 54m 58.22s +34° 02′ 05.7″ 5.73 0.87 305 G7III:
99283 55797 11h 25m 57.18s +55° 51′ 01.2″ 5.73 0.59 348 K0III
62 UMa 62 101606 57029 11h 41m 34.50s +31° 44′ 45.5″ 5.73 2.67 133 F4V
102713 57670 11h 49m 41.80s +34° 55′ 54.3″ 5.73 1.52 227 F5IV
77309 44504 09h 04m 00.40s +54° 17′ 02.0″ 5.74 0.67 336 A2V
32 UMa 32 88983 50448 10h 18m 02.15s +65° 06′ 30.1″ 5.74 1.32 249 A8III
92354 52338 10h 41m 48.31s +68° 26′ 36.8″ 5.74 −0.53 586 K3III
22 UMa 22 82189 47013 09h 34m 53.39s +72° 12′ 21.1″ 5.77 2.28 163 F7V
CG UMa CG 80390 45915 09h 21m 43.30s +56° 41′ 57.3″ 5.79 −0.03 477 M4IIIa
39 UMa 39 92728 52478 10h 43m 43.32s +57° 11′ 57.6″ 5.79 0.53 368 A0Vs
106884 59920 12h 17m 29.56s +53° 11′ 29.2″ 5.80 0.46 382 K6III
71 UMa 71 108135 60584 12h 25m 03.22s +56° 46′ 40.3″ 5.82 −1.99 1190 M3III
99747 56035 11h 29m 04.70s +61° 46′ 40.0″ 5.83 3.24 107 F5Vawvar
66 UMa 66 103605 58181 11h 55m 58.41s +56° 35′ 54.8″ 5.83 0.90 315 K1III
HD 111456 111456 62512 12h 48m 39.34s +60° 19′ 11.6″ 5.83 3.91 79 F5V
112486 63143 12h 56m 17.64s +54° 05′ 58.1″ 5.84 1.37 256 A5m
85841 48893 09h 58m 22.91s +72° 52′ 46.6″ 5.86 0.58 370 K3III:
EN UMa EN 89343 50685 10h 21m 03.43s +68° 44′ 51.8″ 5.88 0.38 410 A7Vn δ Sct variable
97989 55086 11h 16m 41.93s +49° 28′ 34.6″ 5.88 0.32 421 K0III:
111270 62402 12h 47m 18.93s +62° 46′ 52.1″ 5.88 1.88 206 A9V
71088 41676 08h 29m 46.29s +67° 17′ 50.7″ 5.89 0.92 322 G8III
96834 54537 11h 09m 38.55s +43° 12′ 27.9″ 5.89 −0.31 566 M2III
73171 42452 08h 39m 17.65s +52° 42′ 42.1″ 5.91 0.48 397 K1III:
94132 53257 10h 53m 31.38s +69° 51′ 14.6″ 5.91 2.72 142 G9IV
78935 45461 09h 15m 52.75s +72° 56′ 47.3″ 5.93 1.18 291 F0III
58 UMa 58 99984 56148 11h 30m 31.17s +43° 10′ 23.0″ 5.94 2.19 183 F4V
VY UMa VY 92839 52577 10h 45m 04.02s +67° 24′ 41.0″ 5.95 −1.75 1132 C5II
104075 58460 11h 59m 17.54s +33° 10′ 01.3″ 5.95 −0.62 671 K1III
79763 45590 09h 17m 31.17s +46° 49′ 01.9″ 5.96 0.70 367 A1V
83126 47401 09h 39m 27.92s +67° 16′ 20.4″ 5.96 −0.15 543 K5
HD 85945 85945 48802 09h 57m 13.57s +57° 25′ 06.1″ 5.97 0.19 466 G8III
120787 67485 13h 49m 45.43s +61° 29′ 22.4″ 5.97 0.55 395 G3V
95129 53726 10h 59m 32.74s +36° 05′ 35.6″ 5.99 −1.19 888 M2III
68951 40889 08h 20m 40.32s +72° 24′ 26.3″ 6.00 −1.32 948 M0III
89319 50546 10h 19m 26.88s +48° 23′ 49.3″ 6.00 2.82 141 K0
90470 51200 10h 27m 28.08s +41° 36′ 04.4″ 6.00 1.89 216 A2V
89414 50635 10h 20m 31.18s +54° 13′ 00.7″ 6.01 0.28 457 K3III:
51 UMa 51 95934 54136 11h 04m 31.28s +38° 14′ 28.9″ 6.01 1.48 263 A3III-IV
98772 55564 11h 22m 51.25s +64° 19′ 49.5″ 6.02 1.34 282 A3V
76 UMa 76 110462 61936 12h 41m 33.95s +62° 42′ 47.1″ 6.02 −0.24 581 A2III
119765 67005 13h 43m 54.80s +52° 03′ 51.9″ 6.02 0.90 345 A1V
94669 53465 10h 56m 14.51s +42° 00′ 30.2″ 6.03 1.13 312 K2III
95241 53791 11h 00m 20.76s +42° 54′ 43.3″ 6.03 2.74 148 F9V
90745 51448 10h 30m 26.65s +64° 15′ 28.1″ 6.07 1.33 289 A7III
EP UMa EP 96707 54540 11h 09m 39.92s +67° 12′ 37.0″ 6.07 0.88 355 F0sp... α² CVn variable
75 UMa 75 108861 60992 12h 30m 04.22s +58° 46′ 04.1″ 6.07 0.48 428 G8III-IV
60 UMa 60 101133 56789 11h 38m 33.54s +46° 50′ 03.4″ 6.09 0.93 351 F5IIIs
37 Lyn (37) 80290 45836 09h 20m 43.79s +51° 15′ 56.6″ 6.14 3.83 95 F3V
101013 56731 11h 37m 53.05s +50° 37′ 05.8″ 6.14 0.39 461 K0p... Barium star
105043 58989 12h 05m 39.76s +62° 55′ 59.9″ 6.14 0.85 373 K2III
113994 63952 13h 06m 22.86s +62° 02′ 31.1″ 6.15 0.83 377 G7III
122866 68637 14h 02m 59.78s +50° 58′ 18.6″ 6.16 1.25 313 A2V
83962 47791 09h 44m 36.62s +64° 59′ 02.6″ 6.18 1.02 351 F3Vn
U UMa U 88651 50222 10h 15m 07.65s +59° 59′ 07.9″ 6.18 −2.46 1743 M0IIIvar
1 CVn (1) 106478 59708 12h 14m 43.43s +53° 26′ 04.8″ 6.18 0.23 505 K0III:
74604 43266 08h 48m 49.28s +66° 42′ 29.4″ 6.20 0.21 514 B8V
98499 55412 11h 20m 53.71s +67° 06′ 03.1″ 6.20 0.55 439 G8
108954 61053 12h 30m 50.12s +53° 04′ 34.2″ 6.20 4.49 72 F9V
73971 42777 08h 43m 00.19s +46° 54′ 03.6″ 6.21 0.70 412 G8III
95057 53706 10h 59m 17.89s +51° 52′ 56.5″ 6.22 −0.38 681 K0
103736 58259 11h 56m 53.27s +61° 32′ 57.5″ 6.22 −0.15 612 G8III
EZ UMa EZ 80953 46247 09h 25m 44.19s +63° 56′ 27.7″ 6.24 −0.73 809 K2III
102942 57805 11h 51m 09.51s +33° 22′ 29.9″ 6.25 2.25 205 Am
84812 48266 09h 50m 23.67s +65° 35′ 35.9″ 6.27 1.41 306 A9Vn
101604 57045 11h 41m 43.52s +55° 10′ 19.2″ 6.28 −1.17 1006 K5
CQ UMa CQ 119213 66700 13h 40m 21.44s +57° 12′ 27.2″ 6.28 1.55 288 A4p SrCrEu α² CVn variable
85583 48638 09h 55m 03.35s +61° 06′ 58.1″ 6.29 0.91 389 K0
99859 56083 11h 29m 43.66s +56° 44′ 15.6″ 6.29 2.13 221 A4m
101151 56784 11h 38m 32.33s +33° 37′ 33.1″ 6.29 −0.16 634 K2III
101177 56809 11h 38m 45.39s +45° 06′ 30.2″ 6.29 4.45 76 G0V Binary star
81025 46168 09h 24m 55.64s +51° 34′ 26.1″ 6.30 0.69 432 G2III
EE UMa EE 99967 56135 11h 30m 24.83s +46° 39′ 26.9″ 6.30 −1.10 985 K2IIICN-1
71553 41927 08h 32m 53.27s +69° 19′ 11.9″ 6.31 −0.08 619 K0
87243 49408 10h 05m 10.40s +52° 22′ 16.7″ 6.31 1.28 330 A5IV
HD 119124 119124 66704 13h 40m 23.35s +50° 31′ 09.4″ 6.31 4.30 82 F7.7V
35 UMa 35 90633 51401 10h 29m 54.43s +65° 37′ 34.7″ 6.32 1.41 313 K2III:
97501 54842 11h 13m 40.10s +41° 05′ 19.7″ 6.33 1.29 332 K2III
99373 55821 11h 26m 25.58s +33° 27′ 02.0″ 6.33 2.53 188 F6IV
73131 42415 08h 38m 59.92s +52° 55′ 30.5″ 6.34 0.08 581 K0
86166 48861 09h 57m 56.84s +45° 24′ 51.8″ 6.34 0.80 418 K0III
41 UMa 41 93132 52685 10h 46m 22.54s +57° 21′ 57.8″ 6.34 −0.49 756 M1III
68 UMa 68 106002 59458 12h 11m 44.89s +57° 03′ 16.0″ 6.34 −1.03 970 K5III
117242 65678 13h 27m 59.73s +52° 44′ 44.3″ 6.34 1.35 325 F0
75487 43624 08h 53m 05.93s +59° 03′ 22.1″ 6.35 2.40 201 F5IV-V
101391 56944 11h 40m 27.44s +57° 58′ 13.3″ 6.35 0.31 526 B9p...
83869 47633 09h 42m 43.12s +48° 25′ 51.8″ 6.36 0.73 435 A1V
90602 51290 10h 28m 36.54s +45° 12′ 44.1″ 6.37 −0.48 763 K0
95256 53860 11h 01m 05.73s +63° 25′ 16.4″ 6.38 1.68 284 A2m
100470 56410 11h 33m 56.38s +36° 48′ 56.7″ 6.38 0.81 424 K0III
110678 62046 12h 43m 04.19s +61° 09′ 19.3″ 6.39 0.56 477 K0
80461 45888 09h 21m 23.61s +45° 22′ 12.5″ 6.40 −0.30 713 K0
93427 52877 10h 48m 49.86s +65° 07′ 56.9″ 6.40 0.85 420 A1V
97138 54721 11h 12m 10.90s +68° 16′ 18.7″ 6.40 1.58 300 A3V
100030 56170 11h 30m 53.14s +47° 55′ 44.8″ 6.40 1.38 328 G9IV
82969 47231 09h 37m 37.52s +60° 12′ 49.5″ 6.41 1.45 321 G5
95233 53798 11h 00m 25.58s +51° 30′ 07.7″ 6.41 0.20 568 G9III
97334 54745 11h 12m 32.53s +35° 48′ 52.0″ 6.41 4.73 71 G0V
69976 41060 08h 22m 44.06s +60° 37′ 52.5″ 6.42 0.75 444 K0III
89268 50509 10h 18m 58.77s +46° 45′ 39.1″ 6.42 −0.61 830 K1III
90508 51248 10h 28m 03.81s +48° 47′ 13.4″ 6.42 4.56 77 G1V
93551 52929 10h 49m 28.82s +63° 48′ 36.0″ 6.42 −0.69 862 K0
Groombridge 1830 103095 57939 11h 52m 55.82s +37° 43′ 58.1″ 6.42 6.61 30 G8VIp Argelander's Star
103928 58369 11h 58m 07.25s +32° 16′ 26.6″ 6.42 3.04 155 A9V
56 Cam (56) 68457 40474 08h 15m 50.52s +60° 22′ 50.1″ 6.43 0.50 499 A7Vm
98673 55485 11h 21m 49.35s +57° 04′ 29.4″ 6.43 1.96 255 A7Vn
77692 44717 09h 06m 43.16s +59° 20′ 40.4″ 6.44 −1.26 1132 A2V
94084 53157 10h 52m 32.11s +52° 30′ 13.4″ 6.44 1.51 315 K2III
95572 54038 11h 03m 27.37s +70° 01′ 51.0″ 6.44 −0.32 734 K0
89389 50606 10h 20m 14.88s +53° 46′ 45.4″ 6.45 4.02 100 F9V
120874 67548 13h 50m 27.77s +58° 32′ 21.9″ 6.45 1.87 269 A3V
73029 42434 08h 39m 10.10s +59° 56′ 21.3″ 6.47 1.25 360 A2Vn
103500 58119 11h 55m 14.10s +36° 45′ 23.4″ 6.47 0.19 588 M3III
119992 67103 13h 45m 13.10s +55° 52′ 48.8″ 6.47 3.84 110 F7IV-V
123977 69107 14h 08m 46.19s +59° 20′ 15.7″ 6.47 0.83 438 K0III
89221 50485 10h 18m 32.91s +43° 02′ 55.1″ 6.48 3.72 116 G5
118536 66385 13h 36m 39.89s +49° 29′ 12.1″ 6.48 0.55 500 K1III
82408 46879 09h 33m 11.26s +45° 30′ 49.9″ 6.49 0.22 584 K0
101150 56816 11h 38m 49.12s +64° 20′ 49.1″ 6.49 0.02 640 A5IV
104179 58512 11h 59m 57.41s +34° 02′ 04.8″ 6.49 1.19 374 A9III
118970 66613 13h 39m 14.92s +51° 48′ 15.1″ 6.49 −1.82 1495 K2
HR 5256 122064 68184 13h 57m 32.10s +61° 29′ 32.4″ 6.49 6.47 33 K3V
81790 46566 09h 29m 47.87s +55° 44′ 43.2″ 6.50 3.27 145 F3Vs
83564 47521 09h 41m 16.76s +55° 51′ 59.7″ 6.50 0.99 412 K1III-IV
83886 47664 09h 43m 07.00s +54° 21′ 49.6″ 6.50 1.69 299 A5m
113436 63647 13h 02m 40.46s +59° 42′ 58.8″ 6.50 0.12 615 A3Vn
117043 65530 13h 26m 00.37s +63° 15′ 38.7″ 6.50 4.85 70 G6V
28 UMa 28 84179 47911 09h 45m 55.38s +63° 39′ 12.3″ 6.51 2.07 252 F2V
65 UMa 65 103483 58112 11h 55m 05.74s +46° 28′ 36.6″ 6.54 −0.41 801 A3Vn
25 LMi (25) 89572 50687 10h 21m 03.67s +41° 50′ 57.8″ 6.78 0.17 685 A0
14 LMi (14) 84453 47973 09h 46m 42.44s +45° 06′ 53.0″ 6.81 2.22 270 K0IV
39 Lyn (39) 80608 45974 09h 22m 32.20s +49° 32′ 41.4″ 6.9 0.1 738 B9
HD 84406 84406 48034 09h 47m 30.55s +63° 14′ 52.1″ 6.94 2.55 258.5 G8IV
65 UMa 65 103498 58117 11h 55m 11.32s +46° 28′ 11.2″ 7.03 −0.46 1025 A1spe...
72 UMa 72 108346 60712 12h 26m 32.60s +55° 09′ 33.9″ 7.03 1.22 472 Am
40 UMa 40 93075 52650 10h 45m 59.86s +56° 55′ 14.9″ 7.11 1.88 363 A8V
HD 96127 96127 54232 11h 05m 46s +44° 18′ 06″ 7.43 -1.23 1761 K2III has a planet (b)
Lalande 21185 95735 54035 11h 03m 20.19s +35° 58′ 11.5″ 7.49 10.46 8.29 M2V Argelander's Second Star; 4th closest star system; has 2 planets
HD 116798 116798 13h 24m 52s +54° 53′ 51″ 7.59 2.18 299[3] A5 Sidus Ludoviciana
HD 79211 79211 09h 14m 22.79157s 52° 41′ 11.7206″ 7.64 8.71 20.09 M0.0 a binary system with a super-Earth planet detected by radial velocity
HD 99706 99706 55994 11h 28m 30s +43° 58′ 00 ″ 7.81 2.26 421 K0 has a planet (b)
W UMa W 83950 47727 09h 43m 45.47s +55° 57′ 09.1″ 7.96 4.48 162 F8Vp+... prototype of W UMa variables
HD 102956 102956 57820 11h 51m 23s +57° 38′ 27″ 8.00 2.5 411 A Aniara; has a planet (b)
HD 118203 118203 66192 13h 34m 02.54s +53° 43′ 42.7″ 8.07 3.33 289 K0 Liesma; has a planet (b)
T UMa T 109729 61532 12h 36m 23.47s +59° 29′ 13.0″ 8.11 −3.19 5930 M4IIIe Mira-type variable star
HD 95127 95127 53733 10h 59m 35.0s +43° 48′ 52″ 8.15 0.77 978 K0 has a planet (b)
HD 68988 68988 40687 08h 18m 22.17s +61° 27′ 38.6″ 8.21 4.36 192 G0 Násti; has two planets (b & c)
R UMa R 92763 52546 10h 44m 38.47s +68° 46′ 32.7″ 8.41 0.95 1013 M4e Mira-type variable star
HD 80606 80606 45982 09h 22m 37.57s +50° 36′ 13.4″ 8.93 5.10 190 G5 has a transiting planet (b)
HIP 57274 57274 11h 44m 41s +30° 57′ 33 ″ 8.96 6.88 85 K5V have three planets (b, c and d)
Winnecke 4 12h 22m 12.5s +58° 04′ 59″ 9.0 3.0 510 K0III Messier 40; optical double star
SZ UMa SZ 55360 11h 20m 04.83s +65° 50′ 47.4″ 9.32 9.52 30 M0 variable star
HAT-P-22 233731 10h 22m 44s +50° 07′ 42″ 9.73 267 G5 has a transiting planet (b)
HD 233604 233604 09h 09m 49.0s +53° 34′ 05″ 10.41 K5 has a planet (b)
HAT-P-13 08h 39m 31.81s +47° 21′ 07.3″ 10.62 3.97 698 G4 has a transiting planet (b), a brown dwarf (c) and one unconfirmed planet (d)
AA UMa AA 09h 46m 59.28s +45° 45′ 56.39″ 11.16 G0 eclipsing binary system
HAT-P-21 11h 25m 06s +41° 01′ 41″ 11.46 4.44 828 G3 Mazaalai; has a transiting planet (b)
GSC 03466-00819 13h 44m 22.58s +48° 01′ 43.2″ 11.86 6.13 457 K Dombay; has a transiting planet HAT-P-3b
HIP 57050 57050 11h 41m 44.63s +42° 45′ 07.1″ 11.88 11.66 36 M4V has a planet (b)
CF UMa CF 11h 52m 58.8s +37° 43′ 07″ 12.00 M5.5V flare star
HAT-P-66 10h 02m 17.5s +53° 57′ 03″ 13 3.16 3023 has a transiting planet HAT-P-66b
WX UMa WX 11h 05m 31.33s +43° 31′ 17.1″ 14.45 16.03 16 M6 flare star
Table legend:

See also

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References

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List of stars in Ursa Major

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The list of stars in Ursa Major encompasses all stellar objects positioned within the boundaries of the constellation as established by the (IAU) in 1930, dividing the into 88 precisely defined regions. , meaning "Greater Bear" in Latin, ranks as the third-largest constellation, occupying 1,280 square degrees in the . It is renowned for the Big Dipper asterism, a prominent pattern formed by seven of its brightest stars—Dubhe, Merak, , , , , and —which has served as a across cultures for millennia. Among the constellation's stars, 22 have proper names officially approved by the IAU's on Star Names, drawing from , Greek, Latin, and other historical origins. The brightest is Alioth ( Ursae Majoris), a white A-type star with an of 1.76, located about 83 light-years away and ranking as the 33rd-brightest star in the night sky. Close behind is ( Ursae Majoris), an orange giant at magnitude 1.79 and 123 light-years distant, which forms a multiple star system. Other key stars include Alkaid ( Ursae Majoris) at magnitude 1.85, a main-sequence star 104 light-years away, and (Zeta Ursae Majoris) at magnitude 2.23, famous for its naked-eye visual double with Alcor (80 Ursae Majoris) and as a quadruple system itself. Ursa Major hosts approximately 223 stars brighter than magnitude 6.5, many of which are cataloged in databases like the Hipparcos Catalogue for their positions, distances, and spectral types. The constellation's stars vary in age and composition, with some belonging to the young Ursa Major Moving Group, a approximately 400 million years old. Beyond individual stars, Ursa Major is a hub for deep-sky observations, though the list focuses solely on stellar members, excluding galaxies and nebulae within its bounds.

Constellation Overview

Position and Visibility

Ursa Major occupies a prominent position in the , spanning approximately 8 hours to 15 hours in and +30° to +70° in . This extensive range places it in the second quadrant (NQ2) of the sky, making it one of the most recognizable constellations for northern observers. The constellation's boundaries, defined as a 28-sided irregular , were officially delineated by the (IAU) in 1930, based on the work of astronomer Eugène Delporte, ensuring every point on the belongs to exactly one constellation. With an area of 1,280 square degrees, Ursa Major ranks as the third-largest constellation, covering about 3.1% of the visible sky. For observers in the , is visible year-round from mid-northern latitudes, with the entire constellation being circumpolar (never setting) above approximately 61° N. The prominent asterism is circumpolar above about 41° N. South of 30° N, parts of the constellation become seasonally visible, rising and setting with the nightly motion of the stars, while parts remain observable as far south as approximately 60° S, though the full extent is only visible north of about 17° S. This persistent visibility from mid-northern latitudes has historically aided astronomers and navigators in orienting themselves to the sky. The constellation's high brings it near the north , with its northernmost extent approaching within about 17° of the pole itself. The proximity of Ursa Major to the north underscores its role in , as its prominent asterism has long been used to locate , the current North Star in the adjacent constellation . By extending an imaginary line through two key stars in the asterism, one can reliably point toward , providing a fixed reference for determining . In ancient cultures, this practical utility intertwined with its mythological depiction as the Great Bear, symbolizing a guardian of the northern skies.

Historical and Cultural Context

In , Ursa Major is associated with the Callisto, a companion of who was seduced by and subsequently transformed into a by the jealous . To prevent her son from accidentally killing her during a hunt, placed Callisto in the sky as the Great Bear, while Arcas became . This tale, rooted in lore, underscores the constellation's depiction as a , a motif that persisted in Western astronomy. The constellation appears in ancient texts, including the Bible's , where it is referenced as ʽĀsh or ʽAyish among the celestial bodies created by God (Job 9:9 and 38:31-32). In the 2nd century CE, the astronomer cataloged in his , describing its stars and configurations as part of a systematic mapping of the heavens that influenced astronomy for centuries. These early references highlight its recognition across and Hellenistic traditions as a prominent northern feature. Arabic astronomers contributed significantly to the naming of Ursa Major's stars, with many modern designations deriving from their terminology; for instance, (Alpha Ursae Majoris) originates from "dubb," meaning "bear," as part of the phrase "back of the greater bear." These names, preserved through medieval translations, bridged and later European star lore. Across cultures, served vital roles in and timekeeping; in ancient , it was known as the Northern Dipper (), symbolizing a cosmic ladle used to mark seasonal changes and imperial authority in calendars. Similarly, its circumpolar motion aided sailors in various northern societies for determining direction, as its pointer stars align toward . This practical significance reinforced its cultural prominence from antiquity onward.

Star Designation Systems

Bayer Designations

The system was introduced by the German astronomer in his influential 1603 star atlas Uranometria, which systematically labeled stars across the sky using lowercase Greek letters followed by the genitive form of the constellation name, generally assigning α to the brightest star and proceeding alphabetically based on apparent brightness and position. This method provided a standardized way to identify stars brighter than about magnitude 6, covering 1,564 stars in total, and remains a cornerstone of stellar . In Ursa Major, a prominent northern constellation spanning 1,280 square degrees, Bayer applied the full sequence of the 24 Greek letters from α to ω to designate its brighter member stars, reflecting the constellation's size and the density of visible stars within its boundaries. The assignments prioritized positional order along the for the seven key stars forming the asterism, running from the bowl to the handle: α Ursae Majoris, β Ursae Majoris, γ Ursae Majoris, δ Ursae Majoris, ε Ursae Majoris, ζ Ursae Majoris, and η Ursae Majoris. This deviated from a strict , as seen in cases where later letters denote stars comparable to or brighter than earlier ones, such as ε Ursae Majoris outshining α Ursae Majoris despite its position in the sequence. Subsequent letters from θ through ω were allocated to additional fainter stars scattered across the constellation, extending the system to cover notable objects beyond the asterism. Bayer's approach in also incorporated influences from earlier catalogs, such as Tycho Brahe's, grouping by approximate magnitude classes before assigning letters, which sometimes led to inconsistencies in perceived order. Letters like χ and ψ, toward the end of the Greek alphabet, were used for stars in the constellation's less prominent regions, ensuring comprehensive coverage without resorting immediately to Roman letters (A, b, c, etc.) that employed in even larger areas. Today, these designations for stars are integral to astronomical catalogs and observations, often supplemented briefly by Flamsteed numbers for finer resolution. The (IAU) has endorsed the system by approving proper names derived from or alongside Bayer labels for several stars, such as for α Ursae Majoris and for η Ursae Majoris, standardizing their use in scientific and public contexts since 2016.

Flamsteed and Other Catalogs

The Flamsteed designations for stars in originate from John Flamsteed's Historia Coelestis Britannica, a comprehensive star catalog published posthumously in 1725 based on observations conducted primarily between 1675 and 1715. This work assigns sequential numbers from 1 to 86 to the stars within the constellation, ordered by increasing as measured from the Greenwich meridian, providing a numerical system that complements earlier letter-based designations like those of . These identifiers facilitated more precise referencing of fainter stars not covered by Bayer's scheme, which prioritized apparent brightness with Greek letters. Modern astronomical databases extensively cross-reference Flamsteed numbers with advanced catalogs to enable accurate identification, positional data, and scientific analysis of stars. The Henry Draper Catalogue (HD), published by the Observatory between 1918 and 1924, includes spectroscopic classifications and magnitudes for over 225,000 stars, linking many entries to their Flamsteed equivalents; for example, the star 47 Ursae Majoris (47 UMa), a G1V-type sun-like star hosting multiple exoplanets, is designated HD 95128 in this system. The Catalogue, released by the in 1997 from the mission's 1989–1993 observations, assigns Hipparcos Input Catalogue (HIP) numbers to about 118,000 stars with sub-arcsecond , integrating Flamsteed data for to refine proper motions and parallaxes. The mission's Data Release 3 (DR3), published in 2022, represents the most comprehensive integration to date, providing astrometric, photometric, and spectroscopic data for over 1.8 billion sources, including all principal Flamsteed stars in with unprecedented precision down to microarcsecond levels for positions and annual yielding distances. This allows for detailed studies of the constellation's , such as membership in moving groups. However, pre-20th-century catalogs like Flamsteed's were limited by ground-based telescopic observations, lacking reliable distance measurements that required later techniques and astrometry to establish.

Catalog of Principal Stars

Brightest Stars by Magnitude

The brightest stars in , ranked by apparent visual magnitude, dominate the constellation's visibility and include several key components of the asterism. These stars span a range of types from hot giants to cooler orange subgiants, with distances from about 47 to 230 light-years, influencing their apparent relative to their intrinsic . Absolute visual magnitudes, calculated using the formula MV=mV−5log⁡10(d/10)M_V = m_V - 5 \log_{10} (d / 10) where dd is distance in parsecs, reveal their true luminosities; for instance, closer stars like those around 80 light-years appear brighter due to proximity despite moderate intrinsic output. Distances are based on DR2 parallaxes (as of 2020); DR3 data may provide refinements.
RankBayer DesignationCommon NameApparent Magnitude (mVm_V)Distance (ly)Spectral TypeColorAbsolute Magnitude (MVM_V)
1ε UMaAlioth1.7783A1III-IVp kB9Blue-white-0.28
2α UMaDubhe1.79123K0IIIOrange-1.09
3η UMaAlkaid1.86104B3 VBlue-0.66
4ζ UMaMizar2.2386A2 VpWhite0.00
5β UMaMerak2.3784A1 IVpsWhite0.28
6γ UMaPhecda2.4483A0 VWhite0.42
7ψ¹ UMa-3.01141K1 IIIOrange-0.16
8μ UMaTania Australis3.06230M0 IIIRed-1.26
9ι UMaTalitha3.1447A7 VWhite1.72
10δ UMaMegrez3.3281A3 VWhite1.37
Alioth, the brightest at magnitude 1.77, is an evolved with peculiar magnetic fields, appearing blue-white due to its A-type spectrum and shining with about 104 solar from 83 light-years away. Dubhe, slightly fainter at 1.79, is an orange giant of spectral type K0III located 123 light-years distant, with an of -1.09 indicating high as a where the primary emits 339 times the Sun's output. Alkaid, at 1.86, is a hot blue main-sequence B3 V star 104 light-years away, its youth and high temperature (around 15,000 K) contributing to its bluish hue and of -0.66. Mizar, with a combined apparent magnitude of 2.23, is a prominent multiple 86 light-years distant, featuring an A2 Vp primary known for its chemical peculiarities and appearance. Merak, at 2.37, is a A1 IVps 84 light-years away, serving as a navigational pointer in the with an of 0.28 and of 64 solar units. Phecda, magnitude 2.44, is an A0 V main-sequence star 83 light-years away, displaying emission lines in its and a color with 0.42. Further down the list, ψ¹ UMa at 3.01 is an orange K1 III giant 141 light-years away, while (δ UMa) at 3.32 is a A3 V star relatively close at 81 light-years, both contributing to the constellation's overall pattern.

Stars Forming the Big Dipper Asterism

The , also known as the or Charles's Wain, is a prominent asterism consisting of seven bright stars within the constellation . These stars form a distinctive ladle-like shape recognizable in the northern sky, serving as a key and a cultural symbol across civilizations. The seven stars are Alpha Ursae Majoris (), Beta Ursae Majoris (Merak), Gamma Ursae Majoris (Phecda), Delta Ursae Majoris (), Epsilon Ursae Majoris (Alioth), Zeta Ursae Majoris (), and Eta Ursae Majoris (). In the asterism's geometry, the "bowl" of the dipper is outlined by and Merak at the outer edge, connected to Phecda and along the inner curve, creating a roughly rectangular shape representing the bear's hindquarters in mythological depictions. The "handle" extends from through Alioth, , and , forming a curved arc suggestive of the bear's tail. This arrangement spans about 25 degrees of the sky, with the stars appearing in a curved line due to their positions along our . A primary navigational function of the involves and Merak, known as the "pointer stars." By drawing an imaginary line from Merak through and extending it approximately five times the distance between these two stars—roughly 5 degrees in angular measure—observers can locate , the North Star, which lies at the end of the Little Dipper's handle in . This method has been used for centuries to determine , particularly useful for sailors and travelers in the . The distances of these stars from vary significantly, highlighting that the Big Dipper is not a physical cluster but an optical grouping. For instance, Alioth is approximately 83 light-years away, while is about 104 light-years distant; the central stars like Merak, Phecda, , and cluster around 80-86 light-years, whereas is farther at 123 light-years. This disparity contributes to the asterism's gradual distortion over millennia due to the stars' proper motions. Five of the stars (Merak, Phecda, , Alioth, and ) are members of the Ursa Major Moving Group, a approximately 80 light-years distant.
StarBayer DesignationProper NamePosition in AsterismDistance (light-years)
Dubheα UMaBowl (outer)123
Merakβ UMaMerakBowl (outer, pointer)84
Phecdaγ UMaPhecdaBowl (inner)83
Megrezδ UMaMegrezBowl (inner, handle base)81
Aliothε UMaAliothHandle (base)83
Mizarζ UMaMizarHandle (middle)86
Alkaidη UMaHandle (tip)104
Distances are approximate, based on Gaia DR2 mission parallax data (as of 2020).

Specialized Star Categories

Variable Stars

Ursa Major contains a variety of variable stars observable by amateur astronomers, ranging from long-period giants to short-period pulsators, with light curves that reflect underlying physical mechanisms such as radial pulsations or rotational modulation of surface features. These stars provide opportunities for visual, photographic, and photometric monitoring, often using from organizations like the American Association of Variable Star Observers (AAVSO) to track magnitude ranges and cycles. A notable example is R Ursae Majoris, a classical Mira variable (type M) located about 4.5° east of Messier 81, visible in binoculars during its brighter phases. This red giant undergoes radial pulsations with a period of approximately 300 days, causing its apparent visual magnitude to vary from around 6.8 at maximum to 13.2 at minimum, making it a prime target for long-term observation campaigns. The pulsation mechanism involves the expansion and contraction of the star's outer envelope, driven by the helium ionization zone, which alters its radius and temperature periodically. AAVSO light curves show irregular secondary variations superimposed on the primary cycle, with recent observations confirming the range extends to fainter limits during deep minima. Semiregular variables like Z Ursae Majoris offer more complex behavior, situated in the bowl of the about 3° west-northwest of Delta Ursae Majoris. Classified as SRb with a spectral type M5IIIE, it exhibits multiple pulsation modes with a mean period of 195.5 days and a possible secondary period near 205 days, resulting in a visual magnitude range of 7.2 to 8.9 currently, though historical AAVSO data indicate extremes from 6.2 to 9.4. These irregularities arise from overlapping pulsation cycles in the star's envelope, allowing amateurs to contribute to studies of late-stage through consistent monitoring. For shorter-period examples, TU Ursae Majoris represents RR Lyrae variables, which are stars pulsating radially with periods under a day. This RRab subtype has a period of 0.5576 days and varies between visual magnitudes 9.26 and 10.34, producing a characteristic sawtooth asymmetric due to the pulsation's compression and expansion phases. RR Lyrae stars like TU UMa are valuable for distance measurements via their , and AAVSO observations help refine shapes for such Population II objects in the constellation. Rotational variables are exemplified by Epsilon Ursae Majoris (Alioth), a chemically peculiar Ap star and Alpha2 Canum Venaticorum (α² CVn) type with a rotation period of 5.1 days. Its brightness fluctuates subtly from 1.75 to 1.78 magnitude as oblique rotate chemical abundance patches—rich in and —into and out of view, altering strengths and . This mechanism highlights magnetic dynamo effects in upper main-sequence s, with AAVSO data supporting the stable photometric cycle visible even to the under .

Multiple and Double Stars

Ursa Major hosts several notable multiple star systems, ranging from close spectroscopic binaries detected through variations to wider visual doubles resolvable with telescopes. These systems provide insights into and dynamics within the constellation's moving group. Detection of such multiples relies on methods like visual observation for angular separations greater than about 0.5 arcseconds and spectroscopic analysis for closer pairs via Doppler shifts in spectral lines. The most famous multiple system in Ursa Major is ζ Ursae Majoris, known as , which forms a quadruple configuration. Mizar A consists of two A-type stars orbiting each other with a short spectroscopic period of 20.54 days and a tiny angular separation of approximately 0.01 arcseconds. Mizar B, visually separated from Mizar A by 14.4 arcseconds, is itself a spectroscopic binary with an of 175.57 days. The entire is an optical companion to 80 Ursae Majoris (Alcor), separated by about 706 arcseconds, forming a naked-eye double often used as a vision test; however, Alcor and Mizar share similar proper motions, suggesting they may be physically associated at a distance of roughly 81 light-years. ν Ursae Majoris (Alula Borealis) is a visual with a primary of magnitude 3.5 and a fainter companion of magnitude 10.1, separated by about 7.3 arcseconds at a position of 149°. At a of approximately 400 light-years, this yields a projected physical separation of roughly 900 AU, implying a long of at least 12,000 years based on estimates and Kepler's laws, though no precise has been determined.

Stars Hosting Exoplanets

Ursa Major contains several stars known to host confirmed , with over 50 such host stars documented as of 2023 according to databases like the NASA Exoplanet Archive, hosting more than 70 confirmed as of 2025, including recent discoveries like the Earth-sized HD 63433 d in the Moving Group. These systems were primarily detected through the method, which measures the gravitational tug of planets on their host stars, though some have also been observed via transits. The in these systems are predominantly gas giants, with masses ranging from sizes to several times that of , and orbital periods from days to years; none reside in the classical of their stars, where liquid water could potentially exist on rocky planets, though undetected terrestrial worlds might occupy those regions in some cases. One of the earliest and most studied systems is that around 47 Ursae Majoris (Flamsteed designation 47 UMa), a G1V star approximately 46 light-years distant. This system features three exoplanets discovered via observations starting in 1996. The innermost, 47 UMa b, has a minimum mass of 2.53 masses and orbits at a semi-major axis of 2.10 AU with a period of 1,078 days, placing it beyond the . The middle planet, 47 UMa c, has a minimum mass of 0.54 masses at 3.60 AU with a 2,391-day period. The outermost, 47 UMa d, has a minimum mass of 1.64 masses at 11.6 AU with a 38.3-year period (14,002 days). These outer s suggest a dynamically stable architecture potentially allowing for undetected inner rocky planets, but no indicators have been confirmed. Another notable system is HD 80606, a G5V about 215 light-years away, which hosts a single highly eccentric detected by in 2001. has a minimum mass of 3.90 masses and an orbital period of 111.8 days at a semi-major axis of 0.85 AU, but its eccentricity of 0.927 brings it as close as 0.03 AU to the during periapsis, subjecting it to extreme temperatures exceeding 1,400 K and rendering it inhospitable for life. The planet's transit was observed in 2009, confirming its size at about 1.0 and providing insights into its atmospheric dynamics during rapid orbital passages. Additional systems include HD 89744, an F7V star hosting a single eccentric (HD 89744 b) with a minimum mass of 6.8 masses, a 256.8-day period, and eccentricity of 0.70, discovered via in 2000; its close approach to the star excludes . HIP 57274, a K4V dwarf, features three planets detected by in 2011: a (HIP 57274 b, 6.4 masses, 8.1-day period at 0.07 AU), and two s (c: 0.46 masses at 0.21 AU with 32.1-day period; d: 1.48 masses at 1.16 AU with 432.8-day period), with the inner too hot for liquid water. HD 68988 (Násti), a G5V star, hosts two s: HD 68988 b (1.84 masses, 6.3-day period at 0.07 AU, ) and c (0.41 masses, 127-day period at 0.44 AU), both discovered via in 2005 and 2010, respectively, outside habitable zones.
Host StarPlanetMin. Mass (Jupiter masses)Semi-Major Axis (AU)Period (days)Discovery Method (Year)Habitability Note
47 UMab2.532.101078Radial Velocity (1996)Outside HZ
47 UMac0.543.602391Radial Velocity (2001)Outside HZ
47 UMad1.6411.614002Radial Velocity (2002)Outside HZ
HD 80606b3.900.85111.8Radial Velocity (2001); Transit (2009)Extreme heat
HD 89744b6.800.92256.8Radial Velocity (2000)Eccentric, hot
HIP 57274b0.02 (6.4 Earth)0.078.1Radial Velocity (2011)Too hot
HIP 57274c0.460.2132.1Radial Velocity (2011)Too hot
HIP 57274d1.481.16432.8Radial Velocity (2011)Outside HZ
HD 68988b1.840.076.3Radial Velocity (2005)Hot Jupiter
HD 68988c0.410.44127Radial Velocity (2010)Marginal HZ edge, gas giant

Observational and Scientific Notes

Proper Motions and Distances

The distances to stars in are determined primarily through trigonometric measurements, which quantify the annual apparent shift in a star's position against background stars due to Earth's orbital motion . The mission (1989–1993) delivered the first comprehensive all-sky astrometric catalog in 1997, with accuracies of approximately 1 mas for stars brighter than visual magnitude 9, enabling reliable distance estimates up to several hundred parsecs for nearby targets like those in . Gaia's ongoing observations since 2013 have vastly enhanced precision, with Data Release 3 (2022) providing median parallax uncertainties of 0.02–0.03 mas for G < 15 mag stars, translating to distance precisions of ~1% at 25 pc and supporting refined 3D mapping of . For instance, Merak (β UMa) has a DR3 parallax of 38.60 ± 1.13 mas, corresponding to a distance of 26 ± 1 pc. Proper motions—the angular rates at which stars appear to shift across the sky, typically in mas/yr—offer insights into tangential velocities and dynamical associations when combined with and radial velocities. (η UMa) displays a notable proper motion with components of μ_α cos δ = –121.17 ± 0.15 mas/yr and μ_δ = –14.91 ± 0.17 mas/yr (total ~122 mas/yr), reflecting its relatively high tangential speed consistent with a young age of ~10 Myr. Not all Big Dipper stars share the same origin; five (Merak, Phecda, , Alioth, and ) co-move as part of the Moving Group, a dispersed kinematic association at an average distance of ~25 pc rather than a bound cluster, as established through proper motions and parallaxes. and are foreground or background interlopers with distinct motions. Principal Ursa Major stars overall span distances of 20–150 pc, underscoring the asterism's projection across varying depths.

Spectral Classifications and Evolution

The stars in Ursa Major exhibit a diverse range of spectral classifications under the Morgan-Keenan (MK) system, which categorizes them based on surface temperature and luminosity class, reflecting their evolutionary stages from main-sequence youth to giant expansion. The principal stars forming the asterism provide representative examples: (η UMa) is classified as B3 V, a hot main-sequence star with a surface temperature of approximately 15,500 K, indicating early hydrogen fusion in its core. In contrast, Alioth (ε UMa) is an A1p star—peculiar due to strong and variable spectral lines—positioned as a young main-sequence object with a temperature around 9,400 K, while (α UMa) represents an evolved K0 III giant at about 4,600 K, having exhausted core hydrogen and expanded after ascending the . Luminosity classes among these stars further delineate their : the V (dwarf) class dominates for younger members like Merak (β UMa, A1 IVps transitioning from ), Phecda (γ UMa, A0 V), (δ UMa, A3 V), and (ζ UMa, A2 V), all fusing hydrogen stably on the . Dubhe's III class signifies its giant phase, where helium fusion sustains after core contraction. assessments, measured as [Fe/H] relative to solar abundance, show near-solar values for the group, around +0.03 dex, influencing line strengths in spectra and linking to Galactic chemical . Evolutionary stages tie closely to age and kinematics: five Big Dipper stars (Merak, Phecda, Megrez, Alioth, Mizar) belong to the Ursa Major Moving Group, a dispersed association of co-moving stars aged approximately 414 million years (with estimates ranging from 300 to 500 million years), placing them in youthful main-sequence phases with ongoing core contraction. Dubhe, at approximately 280 million years, has evolved off the main sequence into subgiant and giant stages, while Alkaid, not a group member, is younger (around 10 million years) and remains firmly on the hot main sequence. On the Hertzsprung-Russell (HR) diagram, the Ursa Major subset clusters along the upper main sequence for A-type members, reflecting their intermediate masses (1.5–3 solar masses) and post-zero-age-main-sequence positions, with Dubhe branching toward the giant luminosity class. This distribution underscores the constellation's mix of contemporaneous formation in the moving group and unrelated interlopers, highlighting diverse stellar life cycles within a shared spatial volume.

References

  1. https://www.go-astronomy.com/constellations.php?Name=Ursa%20Major
  2. https://iauarchive.eso.org/public/themes/constellations/
  3. https://www.constellation-guide.com/constellation-list/ursa-major-constellation/
  4. https://noirlab.edu/public/education/constellations/ursa-major/
  5. https://theskylive.com/sky/constellations/ursa_major-bright-stars
  6. https://iopscience.iop.org/article/10.1088/0004-637X/813/1/58
  7. https://encyclopedia.pub/entry/56292
  8. https://www.space.com/ursa-major-constellation-great-bear
  9. https://web.pa.msu.edu/people/horvatin/Astronomy_Facts/constellation_pages/ursa_major.htm
  10. https://www.nps.gov/articles/bearsinstars.htm
  11. https://burro.astr.cwru.edu/Academics/Astr201/Spring/Spring.html
  12. http://dlib.nyu.edu/awdl/isaw/isaw-papers/23/
  13. https://adsabs.harvard.edu/full/1948ASPL....5..281C
  14. https://www2.nau.edu/~gaud/bio301/content/erlast.htm
  15. https://press.uchicago.edu/books/hoc/HOC_V2_B2/HOC_VOLUME2_Book2_chapter13.pdf
  16. http://www.ianridpath.com/startales/bayer.html
  17. https://www.lindahall.org/about/news/scientist-of-the-day/johann-bayer/
  18. https://www.eurekalert.org/news-releases/646047
  19. https://archive.org/details/historia-coelestis-britannica-vol.-1
  20. https://www.esa.int/Science_Exploration/Space_Science/Gaia/Why_was_it_so_difficult_to_study_the_Milky_Way_before_Gaia
  21. https://www.cosmos.esa.int/web/gaia/release
  22. http://simbad.cds.unistra.fr/simbad/sim-basic?Ident=epsilon+UMa
  23. https://iopscience.iop.org/article/10.3847/1538-3881/ad08be
  24. http://simbad.cds.unistra.fr/simbad/sim-basic?Ident=alpha+UMa
  25. http://simbad.cds.unistra.fr/simbad/sim-basic?Ident=eta+UMa
  26. http://simbad.cds.unistra.fr/simbad/sim-basic?Ident=zeta+UMa
  27. http://simbad.cds.unistra.fr/simbad/sim-basic?Ident=beta+UMa
  28. http://simbad.cds.unistra.fr/simbad/sim-basic?Ident=gamma+UMa
  29. http://simbad.cds.unistra.fr/simbad/sim-basic?Ident=psi+UMa
  30. http://simbad.cds.unistra.fr/simbad/sim-basic?Ident=delta+UMa
  31. https://www.constellation-guide.com/big-dipper/
  32. https://www.astronomy.com/observing/explore-the-big-dipper-this-winter/
  33. https://www.constellation-guide.com/pointer-stars/
  34. https://www.aavso.org/vsots_zuma
  35. https://www.popastro.com/variablestar/reference/guides/guide-to-r-ursae-majoris/
  36. https://www.universeguide.com/star/52546/rursaemajoris
  37. https://www.aavso.org/vsots_archive
  38. https://ui.adsabs.harvard.edu/abs/1980JAVSO...9...74S/abstract
  39. https://www.skyatnightmagazine.com/advice/alioth
  40. https://adsabs.harvard.edu/full/2012SASS...31..147G
  41. https://adsabs.harvard.edu/full/2008MNRAS.384..173F
  42. https://adsabs.harvard.edu/full/1965PDAO...12..361G
  43. http://stars.astro.illinois.edu/sow/mizar.html
  44. https://exoplanetarchive.ipac.caltech.edu/
  45. https://www.aanda.org/articles/aa/abs/2001/32/aade293/aade293.html
  46. https://iopscience.iop.org/article/10.1086/312611
  47. https://iopscience.iop.org/article/10.1088/0004-637X/745/1/21
  48. https://vizier.cds.unistra.fr/viz-bin/VizieR?-source=I/355/gaiadr3
  49. https://iopscience.iop.org/article/10.1086/368241
  50. https://www.star-facts.com/alkaid/
  51. https://www.star-facts.com/alioth/
  52. https://www.star-facts.com/dubhe/
  53. https://www.star-facts.com/merak/
  54. https://www.star-facts.com/phecda/
  55. https://www.star-facts.com/megrez/
  56. https://astropixels.com/stars/Mizar-01.html
  57. https://www.aanda.org/articles/aa/full_html/2017/01/aa22526-13/aa22526-13.html
  58. https://arxiv.org/abs/astro-ph/0507720
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