148:. The stars have a helium rich atmosphere. As helium is compressed it becomes more ionised, which is more opaque. So at the dimmest part in the cycle the star has highly ionised opaque helium in its atmosphere blocking part of the light from escaping. The energy from this “blocked light” causes the helium to heat up then expand, become more transparent and therefore allow more light through. As more light is let through the star appears brighter and, with the expansion, the helium begins to cool down. Hence the helium contracts under gravity and heats up again and the cyclical process continues. Throughout their lifetime Delta Scuti stars exhibit pulsation when they are situated on the classical Cepheid
20:
1501:
143:
Delta Scuti stars exhibit both radial and non-radial luminosity pulsations. Non-radial pulsations are when some parts of the surface move inwards and some outward at the same time. Radial pulsations are a special case, where the star expands and contracts around its equilibrium state by altering the
825:
Garg, A.; Cook, K. H.; Nikolaev, S.; Huber, M. E.; Rest, A.; Becker, A. C.; Challis, P.; Clocchiatti, A.; Miknaitis, G.; Minniti, D.; Morelli, L.; Olsen, K.; Prieto, J. L.; Suntzeff, N. B.; Welch, D. L.; Wood-Vasey, W. M. (2010). "High-amplitude δ-Scutis in the Large
Magellanic Cloud".
743:
Poleski, R.; Soszyński, I.; Udalski, A.; Szymański, M. K.; Kubiak, M.; Pietrzyński, G.; Wyrzykowski, Ł.; Szewczyk, O.; Ulaczyk, K. (2010). "The
Optical Gravitational Lensing Experiment. The OGLE-III Catalog of Variable Stars. VI. Delta Scuti Stars in the Large Magellanic Cloud".
89:
are generally considered to be a subclass of Delta Scuti variables that contain old stars, and can be found in globular clusters. SX Phe variables also follow a period-luminosity relation. One last sub-class are the pre-main sequence (PMS) Delta Scuti variables.
703:
Majaess, Daniel J.; Turner, David G.; Lane, David J.; Krajci, Tom (2011). "Deep
Infrared ZAMS Fits to Benchmark Open Clusters Hosting delta Scuti Stars".
663:
Majaess, D. J.; Turner, D. G.; Lane, D. J.; Henden, A. A.; Krajci, T. (2011). "Anchoring the
Universal Distance Scale Via a Wesenheit Template".
967:
144:
radius to maintain its spherical shape. The variations are due to the swelling and shrinking of the star through the
Eddington Valve or
188:
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192:
74:
1310:
1302:
1252:
1111:
1098:
605:; Clementini, Gisella; Marconi, Marcella (2007). "A δ Scuti Distance to the Large Magellanic Cloud".
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8:
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187:
and may never be able to satisfy particular standards for completeness. You can help by
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175:(α Lyrae) is a suspected Delta Scuti variable, but this remains unconfirmed.
1523:
1106:
976:
475:
253:
163:
with a period of 4.65 hours. Other well known Delta Scuti variables include
129:
66:
786:"SX Phoenicis period-luminosity relations and the blue straggler connection"
509:
1330:
1193:
45:
when the V-band amplitude is larger than 0.3 mag.) is a subclass of young
1505:
866:
619:
156:
110:
24:
284:
1315:
1273:
705:
Journal of the
American Association of Variable Star Observers (Jaavso)
665:
Journal of the
American Association of Variable Star Observers (Jaavso)
159:(δ Sct), which exhibits brightness fluctuations from +4.60 to +4.79 in
137:
125:
411:
347:
152:. They then move across from the main sequence into the giant branch.
121:
of the fluctuations can vary greatly. The stars are usually A0 to F5
1350:
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114:
29:
19:
940:
636:
587:
562:
315:
168:
82:
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677:
945:
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132:
stars. The high-amplitude Delta Scuti variables are also called
1444:
937:
at The
Encyclopedia of Astrobiology, Astronomy, and Spaceflight
164:
101:
surveys have detected nearly 3000 Delta Scuti variables in the
930:
Combined
General Catalog of Variable Stars (GCVS4.2, 2004 Ed.)
888:
98:
557:
1325:
172:
94:
1500:
601:
105:. Typical brightness fluctuations are from 0.003 to 0.9
702:
662:
567:
494:
489:
462:
457:
429:
424:
398:
393:
366:
361:
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328:
302:
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271:
266:
824:
561:; Madsen, J. B.; Barnes, J.; Ericksen, B. F. (2000).
57:
and have been used to establish the distance to the
155:The prototype of these sorts of variable stars is
790:Monthly Notices of the Royal Astronomical Society
1521:
941:AAVSO: Delta Scuti and the Delta Scuti variables
783:
698:
696:
961:
909:
907:
738:
736:
658:
656:
654:
889:I.A., Vasil'yev; et al. (1989-03-17).
779:
777:
693:
595:
551:
113:over a period of a few hours, although the
968:
954:
904:
733:
651:
865:
839:
809:
784:Cohen, Roger E.; Sarajedini, Ata (2012).
757:
716:
676:
618:
586:
774:
18:
818:
525:
1522:
949:
563:"The Distance to the Galactic Center"
375:5th brightest star in the night sky
928:Samus N.N., Durlevich O.V., et al.
13:
975:
922:
14:
1546:
1499:
811:10.1111/j.1365-2966.2011.19697.x
77:in certain passbands like other
16:Subclass of young pulsating star
199:
882:
499:
467:
434:
403:
371:
338:
307:
276:
49:. These variables as well as
27:for Delta Scuti, plotted from
1:
1089:Blue large-amplitude pulsator
518:
893:. Commission 27 of the I.A.U
891:"On the Variability of Vega"
448:Lampens & Rufuen (1990)
7:
858:10.1088/0004-6256/140/2/328
342:In eclipsing binary system
178:
10:
1551:
914:(apparent visual magnitude
182:
75:period-luminosity relation
1495:
1462:
1432:
1411:
1395:
1388:
1301:
1266:
1240:
1205:
1162:
1155:
1125:
1097:
1059:
992:
983:
508:Other examples include -
245:
240:
235:
205:
200:
73:. The variables follow a
828:The Astronomical Journal
607:The Astronomical Journal
230:
220:
210:
1138:Solar-like oscillations
1079:Slowly pulsating B-type
1215:Luminous blue variable
1046:Rapidly oscillating Ap
444:V701 Coronae Australis
136:, after the prototype
103:Large Magellanic Cloud
87:SX Phoenicis variables
59:Large Magellanic Cloud
34:
1535:Delta Scuti variables
22:
1403:Rotating ellipsoidal
1311:AM Canum Venaticorum
1258:RS Canum Venaticorum
189:adding missing items
39:Delta Scuti variable
1440:α Canum Venaticorum
850:2010AJ....140..328G
802:2012MNRAS.419..342C
768:2010AcA....60....1P
727:2011JAVSO..39..219M
687:2011JAVSO..39..122M
629:2007AJ....133.2752M
603:McNamara, D. Harold
579:2000PASP..112..202M
1424:FK Comae Berenices
1220:R Coronae Borealis
1010:Classical cepheids
232:Range of magnitude
202:Designation (name)
161:apparent magnitude
51:classical cepheids
41:(sometimes termed
35:
1530:Cepheid variables
1517:
1516:
1482:Planetary transit
1458:
1457:
1379:
1372:
1353:
1339:
1321:Luminous red nova
1297:
1296:
1279:Gamma Cassiopeiae
1232:Yellow hypergiant
1228:
1196:
1189:
1151:
1150:
1037:
1017:
506:
505:
150:instability strip
63:globular clusters
1542:
1504:
1503:
1393:
1392:
1375:
1368:
1349:
1335:
1253:FS Canis Majoris
1222:
1192:
1185:
1160:
1159:
1023:
1007:
990:
989:
970:
963:
956:
947:
946:
916:
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902:
901:
899:
898:
886:
880:
879:
869:
843:
822:
816:
815:
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781:
772:
771:
761:
746:Acta Astronomica
740:
731:
730:
720:
700:
691:
690:
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649:
648:
622:
620:astro-ph/0702107
613:(6): 2752–2763.
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459:
431:
426:
400:
395:
368:
363:
335:
330:
304:
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273:
268:
198:
197:
193:reliable sources
134:AI Velorum stars
79:standard candles
55:standard candles
1550:
1549:
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1544:
1543:
1541:
1540:
1539:
1520:
1519:
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1506:Star portal
1498:
1491:
1487:W Ursae Majoris
1454:
1433:Magnetic fields
1428:
1407:
1384:
1293:
1262:
1248:Double periodic
1241:Eruptive binary
1236:
1207:
1201:
1147:
1121:
1093:
1061:
1060:Blue-white with
1055:
997:
979:
974:
935:AI Velorum star
925:
923:Further reading
920:
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894:
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883:
823:
819:
782:
775:
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559:McNamara, D. H.
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146:Kappa-mechanism
71:Galactic Center
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1370:Symbiotic nova
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1318:
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1307:
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1284:Lambda Eridani
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1117:Slow irregular
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977:Variable stars
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637:10.1086/513717
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588:10.1086/316512
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53:are important
47:pulsating star
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1412:Stellar spots
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1396:Non-spherical
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1133:Gamma Doradus
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1113:
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1084:PV Telescopii
1082:
1080:
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1067:
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1064:
1062:early spectra
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868:
867:1969.1/181688
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589:
584:
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568:
564:
560:
554:
538:
537:Hipparcos ESA
534:
533:"Light Curve"
528:
524:
516:
515:
514:β Cassiopeiae
511:
502:
493:
488:
485:
482:
480:Kurtz (1982)
479:
477:
476:QQ Telescopii
474:
473:
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242:Spectral type
238:
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217:
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190:
186:
176:
174:
170:
166:
162:
158:
153:
151:
147:
141:
139:
135:
131:
130:main sequence
127:
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120:
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112:
108:
104:
100:
96:
91:
88:
84:
80:
76:
72:
68:
67:open clusters
64:
60:
56:
52:
48:
44:
43:dwarf cepheid
40:
32:
31:
26:
21:
1497:
1377:Z Andromedae
1359:SW Sextantis
1337:Intermediate
1176:Herbig Ae/Be
1051:SX Phoenicis
1013:
998:cepheid-like
929:
913:
895:. Retrieved
884:
831:
827:
820:
793:
789:
749:
745:
708:
704:
668:
664:
610:
606:
597:
573:(768): 202.
570:
566:
553:
541:. Retrieved
536:
527:
507:
486:6.58 (blue)
483:6.53 (blue)
246:
241:
236:
231:
221:
211:
206:
201:
185:dynamic list
171:(β Leonis).
154:
142:
133:
92:
42:
38:
36:
28:
1419:BY Draconis
1303:Cataclysmic
1208:supergiants
1143:White dwarf
1112:Semiregular
1099:Long-period
1074:Beta Cephei
1069:Alpha Cygni
1026:BL Herculis
1014:Delta Scuti
543:17 February
157:Delta Scuti
25:light curve
1524:Categories
1477:Beta Lyrae
1450:SX Arietis
1316:Dwarf nova
1289:Wolf–Rayet
1206:Giants and
1187:FU Orionis
1030:W Virginis
897:2007-10-30
834:(2): 328.
796:(1): 342.
711:(2): 219.
671:(1): 122.
519:References
510:σ Octantis
468:F2 III/IV
438:prototype
183:This is a
138:AI Velorum
107:magnitudes
69:, and the
1464:Eclipsing
1364:Symbiotic
1351:Hypernova
1345:Supernova
1225:DY Persei
1164:Protostar
985:Pulsating
876:118386274
841:1004.0955
759:1004.0950
718:1102.1705
678:1007.2300
226:magnitude
216:magnitude
207:Discovery
115:amplitude
30:Hipparcos
1389:Rotating
1156:Eruptive
1041:RR Lyrae
1034:RV Tauri
994:Cepheids
752:(1): 1.
645:18053647
497: h
465: h
435:F2 IIIp
432: h
401: h
369: h
336: h
316:HD 40372
305: h
285:ε Cephei
274: h
254:γ Boötis
179:Examples
169:Denebola
83:Cepheids
81:such as
1194:T Tauri
1021:Type II
846:Bibcode
798:Bibcode
764:Bibcode
723:Bibcode
683:Bibcode
625:Bibcode
575:Bibcode
412:δ Scuti
381:HR 1170
350:(Vega)
348:α Lyrae
247:Comment
222:Minimum
212:Maximum
1445:Pulsar
1005:Type I
874:
643:
500:F2 IV
355:−0.02
277:A7III
237:Period
165:Altair
119:period
1472:Algol
1331:Polar
1274:Flare
1267:Other
1181:Orion
1126:Other
872:S2CID
836:arXiv
754:arXiv
713:arXiv
673:arXiv
641:S2CID
615:arXiv
539:. ESA
454:5.73
451:5.69
421:4.79
418:4.60
404:A9IV
390:5.91
387:5.77
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358:0.07
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291:4.15
263:3.07
260:3.02
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545:2022
512:and
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399:2.39
394:0.14
367:2.57
362:0.03
329:0.04
303:0.98
298:0.06
272:6.96
267:0.05
173:Vega
167:and
123:type
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95:OGLE
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1168:PMS
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