Cataclismic variable stars

Example observations of cataclismic variable stars.

Nova in Eridanus was discovered by K. Itagaki (Japan) on Nov 25^th 2009 as a star 8.1 magnitude in brightness (according to CBAT). Equatorial coordinates of the star: α: 4^h 47^m 54^s, δ: -10° 10′ 45″ (constellation Eridanus, almost 7° SW from Rigel (β Orionis). According to IAUC 9098 the nova has named by GCVS team as KT Eri.

We have checked earlier pictures of this area on the sky and it turned out, nova is visible in our data since 2009 November 13^th.

"Pi of the Sky" images 1°x1° (click at the picture to enlarge):

Our light curve (click in the picture to enlarge) and some of our data points (data in R filter comes from second camera):

Some of our data

HJD Date UT magnitude

R filter C filter

2455148.608 2009.11.13 2:29 7.98 8.43

2455148.806 2009.11.13 7:14 7.10 -

2455149.810 2009.11.14 7:19 5.71 5.84

2455150.813 2009.11.15 7:25 5.60 5.99

2455151.807 2009.11.16 7:16 5.92 6.45

2455152.802 2009.11.17 7:08 6.09 6.71

2455153.601 2009.11.18 2:18 6.50 6.94

2455153.807 2009.11.18 7:16 6.64 6.94

2455154.805 2009.11.19 7:12 6.59 7.19

2455155.806 2009.11.20 7:13 6.94 7.48

2455156.606 2009.11.21 2:25 6.78 7.41

2455157.604 2009.11.22 2:23 - 7.79

2455158.621 2009.11.23 2:48 - 7.76

2455158.807 2009.11.23 7:15 - 7.77

2455160.599 2009.11.25 2:15 - 8.05

2455161.795 2009.11.26 6:59 - 8.11

2455162.600 2009.11.27 2:16 7.63 8.24

2455162.815 2009.11.27 7:26 7.74 8.21

2455163.604 2009.11.28 2:23 8.02 8.24

2455164.606 2009.11.29 8:54 7.73 8.37

2455164.813 2009.11.29 7:24 8.03 8.39

2455165.610 2009.11.30 2:32 8.10 8.55

2455165.809 2009.11.30 7:18 8.24 8.50

2455167.600 2009.12.02 2:18 8.37 8.77

2455168.598 2009.12.03 2:14 8.05 -

2455168.807 2009.12.03 7:15 8.08 8.67

2455172.600 2009.12.07 2:17 8.75 9.24

2455172.807 2009.12.07 7:15 8.65 9.12

HJD	Date	UT	magnitude
Some of our data
HJD	Date	UT	R filter	C filter
2455148.608	2009.11.13	2:29	7.98	8.43
2455148.806	2009.11.13	7:14	7.10	-
2455149.810	2009.11.14	7:19	5.71	5.84
2455150.813	2009.11.15	7:25	5.60	5.99
2455151.807	2009.11.16	7:16	5.92	6.45
2455152.802	2009.11.17	7:08	6.09	6.71
2455153.601	2009.11.18	2:18	6.50	6.94
2455153.807	2009.11.18	7:16	6.64	6.94
2455154.805	2009.11.19	7:12	6.59	7.19
2455155.806	2009.11.20	7:13	6.94	7.48
2455156.606	2009.11.21	2:25	6.78	7.41
2455157.604	2009.11.22	2:23	-	7.79
2455158.621	2009.11.23	2:48	-	7.76
2455158.807	2009.11.23	7:15	-	7.77
2455160.599	2009.11.25	2:15	-	8.05
2455161.795	2009.11.26	6:59	-	8.11
2455162.600	2009.11.27	2:16	7.63	8.24
2455162.815	2009.11.27	7:26	7.74	8.21
2455163.604	2009.11.28	2:23	8.02	8.24
2455164.606	2009.11.29	8:54	7.73	8.37
2455164.813	2009.11.29	7:24	8.03	8.39
2455165.610	2009.11.30	2:32	8.10	8.55
2455165.809	2009.11.30	7:18	8.24	8.50
2455167.600	2009.12.02	2:18	8.37	8.77
2455168.598	2009.12.03	2:14	8.05	-
2455168.807	2009.12.03	7:15	8.08	8.67
2455172.600	2009.12.07	2:17	8.75	9.24
2455172.807	2009.12.07	7:15	8.65	9.12