M31-004425.18 (J004425.18+413452.2)

Target Notes

Open a color composite thumbnail image of M31-004425.18

Classification: OB-Supergiant

(Candidate LBV) No blend concerns

Find In Simbad Query LGGS Massey (2016) at VizieR Query CAT WISE (Eisenhardt et al., 2020) at VizieR Query Gaia DR3 (2022) at VizieR LBT Spectra @UMN
Query Kaluzny et al. (1998) M31 Survey at VizieR
Query POINT-AGAPE An et al. (2004) M31 Survey at VizieR

Photometry Table

Download table (txt) Key to Flags in Table Key For Images Plot/Graph Variability

MJD	V	*	Image	B	*	Image	R	*	Images	I	*	Images
56142.32	17.40± 0.05	T		--	-	-	--	-	-	--	-	-
56267.15	--	-	-	--	-	-	17.08± 0.03	T		--	-	-
56490.37	17.33± 0.04	-		17.60± 0.05	-		--	-	-	--	-	-
56536.23	17.12± 0.07	A		--	-	-	16.98± 0.04	A		--	-	-
56915.13	17.47± 0.04	-		17.65± 0.04	-		17.17± 0.04	-		--	-	-
57227.31	17.35± 0.04	-		17.59± 0.04	-		17.10± 0.04	-		--	-	-
57310.08	17.28± 0.03	-		--	-	-	--	-	-	16.90± 0.06	-
57633.32	17.50± 0.04	A		17.69± 0.05	A		17.27± 0.05	A		--	-	-
57638.27	17.49± 0.05	-		--	-	-	--	-	-	17.05± 0.05	-
57928.37	17.61± 0.04	-		17.76± 0.04	-		17.34± 0.04	-		17.11± 0.07	-
57958.29	17.61± 0.04	-		17.75± 0.05	-		--	-	-	17.20± 0.05	-
58043.06	17.58± 0.04	-		17.73± 0.04	-		--	-	-	17.19± 0.06	-
58098.09	17.58± 0.04	-		17.77± 0.04	-		17.32± 0.04	A		--	-	-
58312.29	17.51± 0.04	-		17.68± 0.04	-		17.26± 0.04	-		--	-	-
58316.26	17.52± 0.04	-		--	-	-	--	-	-	17.10± 0.05	-
58341.23	17.34± 0.05	-		17.55± 0.05	-		--	-	-	--	-	-
58366.12	17.42± 0.04	-		17.67± 0.04	-		--	-	-	--	-	-
58375.12	17.38± 0.04	-		--	-	-	17.11± 0.04	-		--	-	-
58403.08	17.55± 0.04	-		--	-	-	--	-	-	17.15± 0.06	-
58433.09	17.50± 0.06	-		17.69± 0.06	-		17.22± 0.06	-		--	-	-
58671.33	17.52± 0.06	A		17.71± 0.05	A		--	-	-	--	-	-
58673.29	17.50± 0.08	-		--	-	-	17.18± 0.07	-		16.96± 0.08	-
58695.34	17.44± 0.05	-		--	-	-	17.19± 0.04	-		17.01± 0.04	-
58696.30	17.50± 0.07	-		17.64± 0.07	-		17.15± 0.08	-		--	-	-
58750.10	17.53± 0.06	A		17.72± 0.05	A		--	-	-	--	-	-
58779.07	17.54± 0.05	A		--	-	-	17.28± 0.03	A		--	-	-
58812.08	17.53± 0.06	A		--	-	-	17.27± 0.08	-		17.09± 0.04	-
59000.39	17.45± 0.07	-		--	-	-	17.31± 0.12	-		--	-	-
59055.31	17.58± 0.07	-		--	-	-	17.33± 0.09	-		--	-	-
59077.20	17.62± 0.07	-		17.82± 0.07	-		17.34± 0.07	-		17.26± 0.10	-
59131.09	17.55± 0.07	-		--	-	-	17.30± 0.07	-		--	-	-
59166.12	17.50± 0.07	-		--	-	-	--	-	-	17.07± 0.09	-
59194.11	17.51± 0.07	-		17.71± 0.07	-		--	-	-	--	-	-
59376.35	17.42± 0.07	-		17.62± 0.07	-		--	-	-	--	-	-
59409.37	17.40± 0.08	-		--	-	-	17.14± 0.08	-		--	-	-
59441.26	17.48± 0.07	-		17.66± 0.08	-		--	-	-	17.04± 0.09	-
59467.11	17.62± 0.08	-		--	-	-	17.31± 0.06	-		--	-	-
59522.04	17.53± 0.07	-		17.72± 0.07	-		--	-	-	17.04± 0.11	-
59546.05	17.50± 0.07	-		--	-	-	17.23± 0.07	T		--	-	-
59583.10	17.47± 0.07	-		17.66± 0.07	T		--	-	-	--	-	-
59739.36	17.57± 0.07	-		17.67± 0.07	-		17.27± 0.07	-		--	-	-
59816.14	17.44± 0.07	-		--	-	-	--	-	-	16.94± 0.07	-
59851.09	17.52± 0.07	-		17.71± 0.07	-		17.30± 0.07	-		--	-	-
59879.03	17.44± 0.07	-		--	-	-	--	-	-	16.99± 0.07	-
59905.07	17.44± 0.07	-		17.61± 0.06	-		17.13± 0.07	-		--	-	-
60147.26	17.41± 0.07	-		17.61± 0.07	-		--	-	-	--	-	-
60172.17	17.43± 0.07	-		17.59± 0.07	-		17.14± 0.06	-		17.05± 0.07	-
60202.10	17.42± 0.06	-		17.59± 0.07	-		--	-	-	--	-	-
60251.01	17.25± 0.08	-		--	-	-	--	-	-	16.79± 0.07	-
60290.10	17.39± 0.07	-		--	-	-	17.17± 0.07	-		--	-	-
60469.35	17.36± 0.07	-		17.59± 0.07	-		--	-	-	--	-	-
60504.31	17.43± 0.07	-		--	-	-	17.15± 0.06	-		--	-	-
60529.23	17.45± 0.07	-		--	-	-	--	-	-	16.97± 0.07	-
60555.13	17.46± 0.06	-		17.62± 0.06	-		17.18± 0.06	-		--	-	-
60587.10	17.40± 0.06	-		--	-	-	--	-	-	16.93± 0.07	-
60649.08	17.38± 0.07	-		17.59± 0.07	-		17.09± 0.07	-		--	-	-
60880.23	17.29± 0.09	-		17.48± 0.09	-		--	-	-	--	-	-
61055.15	17.30± 0.07	-		--	-	-	--	-	-	16.81± 0.09	-

Download table (txt) Key to Flags in Table Key For Images Plot/Graph Variability

Plots of Brightness and Color

Key for Plot Variability Photometry Table Target Notes

Open a plot of photometry for M31-004425.18 Open a plot of color for M31-004425.18

Key for Plot Variability Photometry Table Target Notes

Variability

Plot/Graph Photometry Table Target Notes

It is very likely that this star is variable.

Correlation factors between bands

If the brightness variation is true variability then there should be a correlation between brightness changes recorded in different filter bands. The following table are the R-squared linear correlation factors calculated for the pairs of bands. The number in parentheses next to the R-squared value is the number of elements used to calculate the correlation factor. The number in square brackets next to the band is the range of magnitudes measured.

	V [0.50 mag]	B [0.34 mag]	R [0.36 mag]
B [0.34 mag]	0.86 (31)
R [0.36 mag]	0.80 (29)	0.87 (15)
I [0.47 mag]	0.85 (21)	0.54 (7)	0.61 (6)

Magnitude-Magnitude Plots

The plots below are provided to check the values in the table above and also to show any non-linear correlations

Opens a plot to assess correlation between bands for M31-004425.18

Plot/Graph Photometry Table Target Notes

I & R Statistics

Welch & Stetson (1993, AJ, 105, 1813) present a method for varible star detection in CCD images from automated surveys. Data from two bands are compared and two statistics are calculated: R and I.

The I-statistic has an expectation value of zero for stars that are NOT variable. A larger non-zero I-value indicates a higher likelihood that the star is variable. The R statistic indicates how the color of the star changes as the variable grows brighter with R = 1.0 being no change in color.

R and I values have only been calculated if there are more than four (4) matched measurements of brightness in each band.

V
(I|R) B
(I|R) R
(I|R)

B
(I|R) 2.01 | 0.76

R
(I|R) 3.08 | 0.89 2.22 | 0.12

I
(I|R) 3.08 | 1.13 0.77 | 0.78 1.29 | 1.35

	V (I\|R)	B (I\|R)	R (I\|R)
B (I\|R)	2.01 \| 0.76
R (I\|R)	3.08 \| 0.89	2.22 \| 0.12
I (I\|R)	3.08 \| 1.13	0.77 \| 0.78	1.29 \| 1.35

Back to catalog index

By John C. Martin, University of Illinois Springfield Henry R. Barber Research Observatory

Generated on 2026-10-12 15:55:15 UT-5