30:
577:
In 1989, it was noticed that the brightness of δ Coronae
Borealis is not constant. Approximately every 45 days, its brightness changes sinusoidally between 4.57 and 4.69, too small to be noticed without close monitoring. The evolutionary state of the star and its probably rotation period mean that
564:
of spectral type G3.5III that is around 2.4 times as massive as the Sun and has swollen to 7.4 times its radius. It has a surface temperature of 5180 K. For most of its existence, Delta
Coronae Borealis was a
1021:
380:
578:
the variations may be due to its rotation with different parts of the surface having spots or different temperatures. This would make it an
573:, having finished burning core hydrogen and just begun burning hydrogen in its shell. It is a strong source of X-rays due to its hot corona.
705:
Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data
Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)".
771:
1166:
63:
1736:
1196:
1741:
569:
of spectral type B before it ran out of hydrogen fuel in its core. Its luminosity and spectrum suggest it has just crossed the
1191:
41:
for Delta
Coronae Borealis, plotted from data published by Fernie (1991). The 59 day rotation period is shown in red.
1186:
1746:
56:
892:
732:
Keenan, Philip C.; McNeil, Raymond C. (1989). "The
Perkins Catalog of Revised MK Types for the Cooler Stars".
1159:
579:
430:
162:
35:
851:
582:. The period has since been refined to 59 days and this is now accepted as the star's rotation period.
1731:
1726:
1511:
1501:
1358:
838:
566:
918:
Niedzielski, A.; Deka-Szymankiewicz, B.; Adamczyk, M.; Adamów, M.; Nowak, G.; Wolszczan, A. (2016).
797:
Niedzielski, A.; Deka-Szymankiewicz, B.; Adamczyk, M.; Adamów, M.; Nowak, G.; Wolszczan, A. (2016).
1711:
1506:
1328:
1303:
1243:
1152:
1278:
1721:
1716:
1531:
1526:
1521:
1516:
1421:
1318:
1273:
1263:
1233:
1223:
1113:
Fernie, J. D. (1987). "Delta
Coronae Borealis : A chromospherically active giant ?".
1092:
486:
125:
1578:
1338:
1268:
1253:
1248:
1228:
531:
494:
482:
478:
388:
1059:
1011:
987:
935:
875:
814:
672:
519:
1323:
1313:
1293:
1288:
1258:
1122:
1055:
983:
931:
870:
810:
779:
741:
714:
668:
608:
257:
8:
1411:
1406:
1401:
1396:
1308:
1298:
1283:
490:
1126:
783:
745:
718:
612:
1391:
1386:
1381:
1376:
1371:
1366:
860:
684:
658:
624:
599:
Fernie, J. D. (October 1991). "R Coronae
Borealis and Delta Coronae Borealis in 1990".
554:
550:
278:
108:
1493:
1215:
628:
451:
49:
20:
1084:
688:
1686:
1144:
1130:
1063:
991:
939:
880:
818:
749:
676:
616:
418:
410:
355:
241:
944:
919:
885:
842:
823:
798:
1622:
1175:
1068:
1043:
996:
971:
707:
VizieR On-line Data
Catalog: B/GCVS. Originally Published in: 2009yCat....102025S
680:
570:
546:
368:
182:
84:
76:
1646:
469:
249:
229:
217:
1705:
543:
539:
498:
206:
157:
71:
917:
796:
335:
308:
1347:
403:
147:
136:
97:
38:
1681:
1676:
1671:
1666:
1661:
1455:
561:
348:
315:
264:
170:
1547:
1484:
1434:
1429:
649:
van
Leeuwen, F. (2007). "Validation of the New Hipparcos Reduction".
29:
1606:
1601:
1596:
1591:
1586:
1465:
1450:
1134:
865:
772:"Compilation of Eggen's UBV data, transformed to UBV (unpublished)"
753:
620:
458:
663:
1632:
1627:
1460:
920:"The Penn State - Toruń Centre for Astronomy Planet Search stars"
799:"The Penn State - Toruń Centre for Astronomy Planet Search stars"
59:
52:
1569:
1016:
896:
513:
395:
328:
269:
847:
Data
Release 2: Summary of the contents and survey properties"
1555:
1470:
1206:
233:
221:
1044:"The X-ray activity of the slowly rotating G giant δ CrB"
972:"The X-ray activity of the slowly rotating G giant δ CrB"
557:
4.57 and 4.69, and it is around 170 light-years distant.
1115:
Publications of the Astronomical Society of the Pacific
601:
Publications of the Astronomical Society of the Pacific
16:
Yellow giant star in the constellation Corona Borealis
1174:
841:; et al. (Gaia collaboration) (August 2018).
769:
1703:
644:
642:
640:
638:
704:
102:+26° 04′ 06.2065″ἴ
1160:
1022:Centre de données astronomiques de Strasbourg
965:
963:
961:
959:
957:
955:
635:
731:
734:The Astrophysical Journal Supplement Series
648:
1167:
1153:
1076:
952:
1067:
995:
943:
884:
874:
864:
822:
662:
592:
776:Catalogue of Eggen's UBV Data., 0 (1986)
1041:
1035:
969:
765:
763:
213:
1704:
1112:
1106:
1004:
913:
911:
909:
907:
905:
725:
700:
698:
598:
1148:
837:
1654:
1192:Corona Borealis in Chinese astronomy
760:
55:
1197:Hercules–Corona Borealis Great Wall
902:
695:
225:
13:
831:
14:
1758:
1082:
790:
1187:List of stars in Corona Borealis
1176:Constellation of Corona Borealis
248:19.7137 ± 0.1820
28:
893:Gaia DR2 record for this source
560:δ Coronae Borealis is a yellow
1737:Henry Draper Catalogue objects
1:
1742:Bright Star Catalogue objects
585:
580:RS Canum Venaticorum variable
567:blue-white main sequence star
1048:Astronomy & Astrophysics
852:Astronomy & Astrophysics
21:δ Coronae Borealis
7:
945:10.1051/0004-6361/201527362
886:10.1051/0004-6361/201833051
824:10.1051/0004-6361/201527362
10:
1763:
1069:10.1051/0004-6361:20041991
997:10.1051/0004-6361:20041991
976:Astronomy and Astrophysics
924:Astronomy and Astrophysics
803:Astronomy and Astrophysics
770:Mermilliod, J.-C. (1986).
681:10.1051/0004-6361:20078357
651:Astronomy and Astrophysics
1645:
1615:
1577:
1568:
1540:
1492:
1483:
1443:
1420:
1357:
1337:
1214:
1205:
1182:
553:varies regularly between
506:
475:
468:
464:
302:
297:
293:
176:
169:
119:
46:
26:
1085:"Delta Coronae Borealis"
481: Coronae Borealis,
1060:2005A&A...431.1027G
988:2005A&A...431.1027G
936:2016A&A...585A..73N
876:2018A&A...616A...1G
815:2016A&A...585A..73N
673:2007A&A...474..653V
279:Absolute magnitude
109:Apparent magnitude
1747:Durchmusterung objects
1093:University of Illinois
528:Delta Coronae Borealis
1517:ρ Coronae Borealis b
1512:ο Coronae Borealis b
1507:κ Coronae Borealis b
1502:ε Coronae Borealis b
1042:Gondoin, P. (2005).
970:Gondoin, P. (2005).
1127:1987PASP...99..183F
784:1986EgUBV........0M
746:1989ApJS...71..245K
719:2009yCat....102025S
613:1991PASP..103.1091F
507:Database references
431:Rotational velocity
23:
555:apparent magnitude
551:apparent magnitude
536:δ Coronae Borealis
470:Other designations
228: -65.28
216: -78.83
158:Variable type
126:Spectral type
19:
1732:Hipparcos objects
1727:Flamsteed objects
1699:
1698:
1695:
1694:
1641:
1640:
1564:
1563:
1479:
1478:
1471:XO-1 (Moldoveanu)
525:
524:
268:(50.7 ± 0.5
1754:
1652:
1651:
1575:
1574:
1490:
1489:
1212:
1211:
1169:
1162:
1155:
1146:
1145:
1139:
1138:
1110:
1104:
1103:
1101:
1099:
1083:Kaler, James B.
1080:
1074:
1073:
1071:
1039:
1033:
1032:
1030:
1028:
1008:
1002:
1001:
999:
982:(3): 1027–1035.
967:
950:
949:
947:
915:
900:
890:
888:
878:
868:
835:
829:
828:
826:
794:
788:
787:
767:
758:
757:
729:
723:
722:
702:
693:
692:
666:
646:
633:
632:
596:
227:
215:
199:
197:
120:Characteristics
112:
92:
87:
47:Observation data
32:
24:
18:
1762:
1761:
1757:
1756:
1755:
1753:
1752:
1751:
1712:Corona Borealis
1702:
1701:
1700:
1691:
1687:RX J1532.9+3021
1647:Galaxy clusters
1637:
1611:
1560:
1536:
1475:
1439:
1416:
1353:
1333:
1201:
1178:
1173:
1143:
1142:
1111:
1107:
1097:
1095:
1081:
1077:
1040:
1036:
1026:
1024:
1010:
1009:
1005:
968:
953:
916:
903:
839:Brown, A. G. A.
836:
832:
795:
791:
768:
761:
730:
726:
703:
696:
647:
636:
597:
593:
588:
576:
571:Hertzsprung gap
547:Corona Borealis
502:
489: 141714,
437: sin
369:Surface gravity
361:
358:
341:
338:
321:
318:
284:
267:
224:
195:
193:
188:
183:Radial velocity
107:
90:
85:Right ascension
83:
77:Corona Borealis
48:
42:
33:
17:
12:
11:
5:
1760:
1750:
1749:
1744:
1739:
1734:
1729:
1724:
1719:
1714:
1697:
1696:
1693:
1692:
1690:
1689:
1684:
1679:
1674:
1669:
1664:
1658:
1656:
1649:
1643:
1642:
1639:
1638:
1636:
1635:
1630:
1625:
1623:FSC 15307+3253
1619:
1617:
1613:
1612:
1610:
1609:
1604:
1599:
1594:
1589:
1583:
1581:
1572:
1566:
1565:
1562:
1561:
1559:
1558:
1556:XO-1b (Negoiu)
1553:
1550:
1544:
1542:
1538:
1537:
1535:
1534:
1529:
1524:
1519:
1514:
1509:
1504:
1498:
1496:
1487:
1481:
1480:
1477:
1476:
1474:
1473:
1468:
1463:
1458:
1453:
1447:
1445:
1441:
1440:
1438:
1437:
1435:145457 (Kamuy)
1432:
1426:
1424:
1418:
1417:
1415:
1414:
1409:
1404:
1399:
1394:
1389:
1384:
1379:
1374:
1369:
1363:
1361:
1355:
1354:
1352:
1351:
1343:
1341:
1335:
1334:
1332:
1331:
1326:
1321:
1316:
1311:
1306:
1301:
1296:
1291:
1286:
1281:
1276:
1271:
1266:
1261:
1256:
1251:
1246:
1241:
1236:
1231:
1226:
1220:
1218:
1209:
1203:
1202:
1200:
1199:
1194:
1189:
1183:
1180:
1179:
1172:
1171:
1164:
1157:
1149:
1141:
1140:
1135:10.1086/131975
1105:
1075:
1054:(3): 1027–35.
1034:
1003:
951:
901:
830:
789:
759:
754:10.1086/191373
724:
694:
634:
621:10.1086/132930
590:
589:
587:
584:
523:
522:
517:
509:
508:
504:
503:
476:
473:
472:
466:
465:
462:
461:
455:
447:
446:
445:4.56 km/s
443:
426:
425:
422:
414:
413:
407:
399:
398:
392:
384:
383:
377:
364:
363:
359:
356:
352:
344:
343:
339:
336:
332:
324:
323:
319:
316:
312:
304:
303:
300:
299:
295:
294:
291:
290:
287:
282:
274:
273:
261:
253:
252:
246:
237:
236:
211:
202:
201:
191:
186:
178:
177:
174:
173:
167:
166:
160:
154:
153:
150:
143:
142:
139:
132:
131:
130:G5III-IV Fe-1
128:
122:
121:
117:
116:
113:
104:
103:
100:
94:
93:
91:15 49 35.64682
88:
80:
79:
74:
68:
67:
44:
43:
27:
15:
9:
6:
4:
3:
2:
1759:
1748:
1745:
1743:
1740:
1738:
1735:
1733:
1730:
1728:
1725:
1723:
1722:Bayer objects
1720:
1718:
1717:G-type giants
1715:
1713:
1710:
1709:
1707:
1688:
1685:
1683:
1680:
1678:
1675:
1673:
1670:
1668:
1665:
1663:
1660:
1659:
1657:
1653:
1650:
1648:
1644:
1634:
1631:
1629:
1626:
1624:
1621:
1620:
1618:
1614:
1608:
1605:
1603:
1600:
1598:
1595:
1593:
1590:
1588:
1585:
1584:
1582:
1580:
1576:
1573:
1571:
1567:
1557:
1554:
1551:
1549:
1546:
1545:
1543:
1539:
1533:
1530:
1528:
1525:
1523:
1520:
1518:
1515:
1513:
1510:
1508:
1505:
1503:
1500:
1499:
1497:
1495:
1491:
1488:
1486:
1482:
1472:
1469:
1467:
1464:
1462:
1459:
1457:
1454:
1452:
1449:
1448:
1446:
1442:
1436:
1433:
1431:
1428:
1427:
1425:
1423:
1419:
1413:
1410:
1408:
1405:
1403:
1400:
1398:
1395:
1393:
1390:
1388:
1385:
1383:
1380:
1378:
1375:
1373:
1370:
1368:
1365:
1364:
1362:
1360:
1356:
1350:
1349:
1345:
1344:
1342:
1340:
1336:
1330:
1327:
1325:
1322:
1320:
1317:
1315:
1312:
1310:
1307:
1305:
1302:
1300:
1297:
1295:
1292:
1290:
1287:
1285:
1282:
1280:
1277:
1275:
1272:
1270:
1267:
1265:
1262:
1260:
1257:
1255:
1252:
1250:
1247:
1245:
1242:
1240:
1237:
1235:
1232:
1230:
1227:
1225:
1222:
1221:
1219:
1217:
1213:
1210:
1208:
1204:
1198:
1195:
1193:
1190:
1188:
1185:
1184:
1181:
1177:
1170:
1165:
1163:
1158:
1156:
1151:
1150:
1147:
1136:
1132:
1128:
1124:
1120:
1116:
1109:
1094:
1090:
1086:
1079:
1070:
1065:
1061:
1057:
1053:
1049:
1045:
1038:
1023:
1019:
1018:
1013:
1007:
998:
993:
989:
985:
981:
977:
973:
966:
964:
962:
960:
958:
956:
946:
941:
937:
933:
929:
925:
921:
914:
912:
910:
908:
906:
898:
894:
887:
882:
877:
872:
867:
862:
858:
854:
853:
848:
846:
840:
834:
825:
820:
816:
812:
808:
804:
800:
793:
785:
781:
777:
773:
766:
764:
755:
751:
747:
743:
739:
735:
728:
720:
716:
712:
708:
701:
699:
690:
686:
682:
678:
674:
670:
665:
660:
657:(2): 653–64.
656:
652:
645:
643:
641:
639:
630:
626:
622:
618:
614:
610:
607:: 1091–1093.
606:
602:
595:
591:
583:
581:
574:
572:
568:
563:
558:
556:
552:
548:
545:
544:constellation
541:
540:variable star
537:
533:
529:
521:
518:
516:
515:
511:
510:
505:
500:
496:
493: 77512,
492:
488:
484:
480:
474:
471:
467:
463:
460:
456:
454:
453:
449:
448:
444:
442:
440:
436:
432:
428:
427:
423:
421:
420:
416:
415:
412:
408:
406:
405:
401:
400:
397:
393:
391:
390:
386:
385:
382:
378:
376:
374:
370:
366:
365:
362:
353:
351:
350:
346:
345:
342:
333:
331:
330:
326:
325:
322:
313:
311:
310:
306:
305:
301:
296:
292:
288:
286:
280:
276:
275:
271:
266:
263:165 ± 2
262:
260:
259:
255:
254:
251:
247:
245:
243:
239:
238:
235:
231:
223:
219:
212:
210:
208:
207:Proper motion
204:
203:
192:
190:
184:
180:
179:
175:
172:
168:
164:
161:
159:
156:
155:
151:
149:
145:
144:
140:
138:
134:
133:
129:
127:
124:
123:
118:
114:
110:
106:
105:
101:
99:
96:
95:
89:
86:
82:
81:
78:
75:
73:
72:Constellation
70:
69:
65:
61:
58:
54:
51:
45:
40:
37:
31:
25:
22:
1346:
1238:
1224:α (Alphecca)
1118:
1114:
1108:
1096:. Retrieved
1088:
1078:
1051:
1047:
1037:
1025:. Retrieved
1015:
1006:
979:
975:
927:
923:
856:
850:
844:
833:
806:
802:
792:
775:
737:
733:
727:
710:
706:
654:
650:
604:
600:
594:
575:
559:
535:
527:
526:
512:
501: 84019
497: 5889,
450:
438:
434:
429:
417:
402:
387:
372:
367:
347:
327:
307:
277:
256:
240:
205:
181:
115:4.57 - 4.69
1229:β (Nusakan)
1098:21 November
1027:25 February
409:−0.12
404:Metallicity
394:5,180
389:Temperature
148:color index
137:color index
98:Declination
39:light curve
36:visual band
1706:Categories
1485:Exoplanets
1456:Gliese 611
866:1804.09365
713:: B/gcvs.
586:References
562:giant star
485:+26°2737,
379:3.29
371:(log
354:34.3
349:Luminosity
200: km/s
171:Astrometry
1548:GJ 3929 b
1339:Flamsteed
1012:"del CrB"
664:0708.1752
629:120378390
532:Latinized
457:851
334:7.4
314:2.4
111: (V)
1570:Galaxies
1466:NGC 6002
1451:ADS 9731
1359:Variable
689:18759600
419:Rotation
360:☉
340:☉
320:☉
281: (M
258:Distance
242:Parallax
1633:IC 4539
1628:IC 1166
1461:GJ 3929
1123:Bibcode
1121:: 183.
1056:Bibcode
984:Bibcode
932:Bibcode
930:: A73.
871:Bibcode
811:Bibcode
809:: A73.
780:Bibcode
742:Bibcode
740:: 245.
715:Bibcode
669:Bibcode
609:Bibcode
542:in the
538:, is a
477:δ CrB,
424:59 days
298:Details
194:−20.356
60:J2000.0
57:Equinox
53:J2000.0
1430:140913
1348:23 Her
1017:SIMBAD
897:VizieR
859:. A1.
687:
627:
549:. Its
514:SIMBAD
329:Radius
163:RS CVn
152:+0.78
141:+0.32
1655:Abell
1616:Other
1541:Other
1494:Bayer
1444:Other
1216:Bayer
1207:Stars
1089:Stars
891:
861:arXiv
778:: 0.
685:S2CID
659:arXiv
625:S2CID
534:from
289:+1.18
226:Dec.:
198:0.035
50:Epoch
1682:2162
1677:2142
1672:2067
1667:2065
1662:2061
1607:6122
1602:6120
1597:6104
1592:6086
1587:6085
1100:2014
1029:2017
845:Gaia
520:data
309:Mass
146:B−V
135:U−B
64:ICRS
1579:NGC
1131:doi
1064:doi
1052:431
992:doi
980:431
940:doi
928:585
895:at
881:doi
857:616
819:doi
807:585
750:doi
677:doi
655:474
617:doi
605:103
499:SAO
491:HIP
459:Myr
452:Age
411:dex
381:cgs
250:mas
244:(π)
230:mas
218:mas
214:RA:
209:(μ)
1708::
1422:HD
1412:UW
1407:TY
1402:RS
1397:RR
1129:.
1119:99
1117:.
1091:.
1087:.
1062:.
1050:.
1046:.
1020:.
1014:.
990:.
978:.
974:.
954:^
938:.
926:.
922:.
904:^
879:.
869:.
855:.
849:.
817:.
805:.
801:.
774:.
762:^
748:.
738:71
736:.
709:.
697:^
683:.
675:.
667:.
653:.
637:^
623:.
615:.
603:.
530:,
495:HR
487:HD
483:BD
479:10
270:pc
265:ly
234:yr
222:yr
185:(R
165:?
66:)
34:A
1552:c
1532:e
1527:d
1522:c
1392:W
1387:V
1382:U
1377:T
1372:S
1367:R
1329:υ
1324:τ
1319:σ
1314:ρ
1309:π
1304:ο
1299:ξ
1294:ν
1289:ν
1284:μ
1279:λ
1274:κ
1269:ι
1264:θ
1259:η
1254:ζ
1249:ζ
1244:ε
1239:δ
1234:γ
1168:e
1161:t
1154:v
1137:.
1133::
1125::
1102:.
1072:.
1066::
1058::
1031:.
1000:.
994::
986::
948:.
942::
934::
899:.
889:.
883::
873::
863::
843:"
827:.
821::
813::
786:.
782::
756:.
752::
744::
721:.
717::
711:1
691:.
679::
671::
661::
631:.
619::
611::
441:)
439:i
435:v
433:(
396:K
375:)
373:g
357:L
337:R
317:M
285:)
283:V
272:)
232:/
220:/
196:±
189:)
187:v
62:(
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
