Color composite thumbnail image of M31-004021.21M31-004021.21 (J004021.21+403117.1)



Target Notes

Color composite thumbnail image of M31-004021.21

Classification: -

No blend concerns

Find In Simbad Query LGGS Massey (2016) at VizieR Query CAT WISE (Eisenhardt et al., 2020) at VizieR Query Gaia EDR3 (2020) at VizieR
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
MJDV*ImageB*ImageR*ImagesI*Images
56599.13 16.68± 0.03-M31-004021.21 in filter V on MJD  56599.130
16.92± 0.04-M31-004021.21 in filter B on MJD  56599.130
16.50± 0.03-M31-004021.21 in filter R on MJD  56599.130
----
56604.11 16.70± 0.03-M31-004021.21 in filter V on MJD  56604.110
16.99± 0.03-M31-004021.21 in filter B on MJD  56604.110
16.49± 0.04-M31-004021.21 in filter R on MJD  56604.110
----
56930.16 16.68± 0.03-M31-004021.21 in filter V on MJD  56930.160
16.99± 0.04-M31-004021.21 in filter B on MJD  56930.160
16.48± 0.04-M31-004021.21 in filter R on MJD  56930.160
----
56951.10 16.69± 0.03-M31-004021.21 in filter V on MJD  56951.100
17.00± 0.03-M31-004021.21 in filter B on MJD  56951.100
16.50± 0.04-M31-004021.21 in filter R on MJD  56951.100
----
57307.14 16.66± 0.04AM31-004021.21 in filter V on MJD  57307.140
M31-004021.21 in filter V on MJD  57307.140
16.97± 0.03AM31-004021.21 in filter B on MJD  57307.140
M31-004021.21 in filter B on MJD  57307.140
16.48± 0.04AM31-004021.21 in filter R on MJD  57307.140
M31-004021.21 in filter R on MJD  57307.140
----
57340.22 16.64± 0.05-M31-004021.21 in filter V on MJD  57340.220
-------- 16.24± 0.07-M31-004021.21 in filter I on MJD  57340.220
57634.30---- 16.97± 0.04TM31-004021.21 in filter B on MJD  57634.300
16.47± 0.06TM31-004021.21 in filter R on MJD  57634.300
----
57638.23 16.66± 0.05-M31-004021.21 in filter V on MJD  57638.230
16.95± 0.05-M31-004021.21 in filter B on MJD  57638.230
16.45± 0.06-M31-004021.21 in filter R on MJD  57638.230
16.28± 0.07-M31-004021.21 in filter I on MJD  57638.230
57743.02 16.79± 0.04-M31-004021.21 in filter V on MJD  57743.020
17.06± 0.03-M31-004021.21 in filter B on MJD  57743.020
16.58± 0.03-M31-004021.21 in filter R on MJD  57743.020
16.36± 0.04-M31-004021.21 in filter I on MJD  57743.020
57958.38 16.74± 0.03-M31-004021.21 in filter V on MJD  57958.380
---- 16.55± 0.04-M31-004021.21 in filter R on MJD  57958.380
16.30± 0.04-M31-004021.21 in filter I on MJD  57958.380
57963.33 16.68± 0.03AM31-004021.21 in filter V on MJD  57963.330
M31-004021.21 in filter V on MJD  57963.330
16.96± 0.03AM31-004021.21 in filter B on MJD  57963.330
M31-004021.21 in filter B on MJD  57963.330
---- 16.28± 0.07-M31-004021.21 in filter I on MJD  57963.330
57964.26 16.72± 0.04-M31-004021.21 in filter V on MJD  57964.260
---- 16.52± 0.04-M31-004021.21 in filter R on MJD  57964.260
----
57988.31 16.75± 0.03-M31-004021.21 in filter V on MJD  57988.310
17.04± 0.04-M31-004021.21 in filter B on MJD  57988.310
---- 16.35± 0.04-M31-004021.21 in filter I on MJD  57988.310
58035.07 16.61± 0.05-M31-004021.21 in filter V on MJD  58035.070
---- 16.40± 0.06-M31-004021.21 in filter R on MJD  58035.070
----
58045.10 16.73± 0.04-M31-004021.21 in filter V on MJD  58045.100
17.02± 0.04-M31-004021.21 in filter B on MJD  58045.100
16.54± 0.04-M31-004021.21 in filter R on MJD  58045.100
----
58067.14 16.73± 0.03-M31-004021.21 in filter V on MJD  58067.140
-------- 16.30± 0.04-M31-004021.21 in filter I on MJD  58067.140
58073.12 16.76± 0.04-M31-004021.21 in filter V on MJD  58073.120
16.98± 0.05-M31-004021.21 in filter B on MJD  58073.120
--------
58077.14 16.77± 0.04-M31-004021.21 in filter V on MJD  58077.140
17.01± 0.03-M31-004021.21 in filter B on MJD  58077.140
---- 16.41± 0.07-M31-004021.21 in filter I on MJD  58077.140
58098.18 16.71± 0.03-M31-004021.21 in filter V on MJD  58098.180
-------- 16.33± 0.04-M31-004021.21 in filter I on MJD  58098.180
58103.11 16.75± 0.04-M31-004021.21 in filter V on MJD  58103.110
17.04± 0.04-M31-004021.21 in filter B on MJD  58103.110
---- 16.30± 0.05-M31-004021.21 in filter I on MJD  58103.110
58316.31 16.71± 0.04AM31-004021.21 in filter V on MJD  58316.310
M31-004021.21 in filter V on MJD  58316.310
16.99± 0.05AM31-004021.21 in filter B on MJD  58316.310
M31-004021.21 in filter B on MJD  58316.310
16.50± 0.04AM31-004021.21 in filter R on MJD  58316.310
M31-004021.21 in filter R on MJD  58316.310
----
58317.29 16.69± 0.04AM31-004021.21 in filter V on MJD  58317.290
M31-004021.21 in filter V on MJD  58317.290
-------- 16.28± 0.06AM31-004021.21 in filter I on MJD  58317.290
M31-004021.21 in filter I on MJD  58317.290
58339.32 16.69± 0.04-M31-004021.21 in filter V on MJD  58339.320
16.96± 0.04-M31-004021.21 in filter B on MJD  58339.320
16.48± 0.05-M31-004021.21 in filter R on MJD  58339.320
----
58342.23 16.68± 0.03-M31-004021.21 in filter V on MJD  58342.230
17.03± 0.04-M31-004021.21 in filter B on MJD  58342.230
---- 16.30± 0.04-M31-004021.21 in filter I on MJD  58342.230
58372.15 16.71± 0.03AM31-004021.21 in filter V on MJD  58372.150
M31-004021.21 in filter V on MJD  58372.150
-------- 16.26± 0.05AM31-004021.21 in filter I on MJD  58372.150
M31-004021.21 in filter I on MJD  58372.150
58373.13 16.63± 0.05-M31-004021.21 in filter V on MJD  58373.130
16.95± 0.05-M31-004021.21 in filter B on MJD  58373.130
--------
58403.14 16.68± 0.03-M31-004021.21 in filter V on MJD  58403.140
16.93± 0.03-M31-004021.21 in filter B on MJD  58403.140
--------
58433.06 16.68± 0.03-M31-004021.21 in filter V on MJD  58433.060
16.99± 0.03-M31-004021.21 in filter B on MJD  58433.060
16.50± 0.03-M31-004021.21 in filter R on MJD  58433.060
----
58672.33 16.70± 0.03AM31-004021.21 in filter V on MJD  58672.330
M31-004021.21 in filter V on MJD  58672.330
17.05± 0.05-M31-004021.21 in filter B on MJD  58672.330
16.55± 0.05-M31-004021.21 in filter R on MJD  58672.330
16.27± 0.06-M31-004021.21 in filter I on MJD  58672.330
58695.25 16.69± 0.03AM31-004021.21 in filter V on MJD  58695.250
M31-004021.21 in filter V on MJD  58695.250
16.98± 0.04-M31-004021.21 in filter B on MJD  58695.250
16.51± 0.03-M31-004021.21 in filter R on MJD  58695.250
16.30± 0.04-M31-004021.21 in filter I on MJD  58695.250
58757.06 16.71± 0.03-M31-004021.21 in filter V on MJD  58757.060
---- 16.50± 0.03-M31-004021.21 in filter R on MJD  58757.060
----
58779.11 16.67± 0.03-M31-004021.21 in filter V on MJD  58779.110
---- 16.47± 0.03-M31-004021.21 in filter R on MJD  58779.110
----
58784.02 16.65± 0.04-M31-004021.21 in filter V on MJD  58784.020
16.93± 0.04-M31-004021.21 in filter B on MJD  58784.020
--------
58836.09 16.72± 0.02AM31-004021.21 in filter V on MJD  58836.090
M31-004021.21 in filter V on MJD  58836.090
---- 16.51± 0.03-M31-004021.21 in filter R on MJD  58836.090
16.25± 0.04-M31-004021.21 in filter I on MJD  58836.090
59001.40 16.77± 0.05TM31-004021.21 in filter V on MJD  59001.400
------------
59019.39 16.81± 0.03-M31-004021.21 in filter V on MJD  59019.390
17.18± 0.06-M31-004021.21 in filter B on MJD  59019.390
--------
59026.34 16.72± 0.04AM31-004021.21 in filter V on MJD  59026.340
M31-004021.21 in filter V on MJD  59026.340
---- 16.50± 0.05-M31-004021.21 in filter R on MJD  59026.340
----
59059.28 16.73± 0.03AM31-004021.21 in filter V on MJD  59059.280
M31-004021.21 in filter V on MJD  59059.280
17.02± 0.03AM31-004021.21 in filter B on MJD  59059.280
M31-004021.21 in filter B on MJD  59059.280
16.56± 0.04-M31-004021.21 in filter R on MJD  59059.280
16.29± 0.06-M31-004021.21 in filter I on MJD  59059.280
59081.20 16.75± 0.04-M31-004021.21 in filter V on MJD  59081.200
-------- 16.34± 0.06-M31-004021.21 in filter I on MJD  59081.200
59082.29 16.71± 0.04-M31-004021.21 in filter V on MJD  59082.290
17.00± 0.04-M31-004021.21 in filter B on MJD  59082.290
16.53± 0.05-M31-004021.21 in filter R on MJD  59082.290
----
59131.15 16.73± 0.04AM31-004021.21 in filter V on MJD  59131.150
M31-004021.21 in filter V on MJD  59131.150
17.06± 0.04-M31-004021.21 in filter B on MJD  59131.150
16.54± 0.05-M31-004021.21 in filter R on MJD  59131.150
----
59166.22 16.76± 0.03AM31-004021.21 in filter V on MJD  59166.220
M31-004021.21 in filter V on MJD  59166.220
-------- 16.36± 0.07AM31-004021.21 in filter I on MJD  59166.220
M31-004021.21 in filter I on MJD  59166.220
59194.17 16.75± 0.04AM31-004021.21 in filter V on MJD  59194.170
M31-004021.21 in filter V on MJD  59194.170
17.02± 0.04-M31-004021.21 in filter B on MJD  59194.170
16.55± 0.04-M31-004021.21 in filter R on MJD  59194.170
----
59380.36 16.76± 0.05AM31-004021.21 in filter V on MJD  59380.360
M31-004021.21 in filter V on MJD  59380.360
17.02± 0.04-M31-004021.21 in filter B on MJD  59380.360
16.61± 0.06-M31-004021.21 in filter R on MJD  59380.360
----
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

Plot of photometry for M31-004021.21Plot of color for M31-004021.21

Key for Plot Variability Photometry Table Target Notes


Variability

Plot/Graph Photometry Table Target Notes

It is 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 [0.26 mag]B [0.20 mag]R [0.21 mag]
B [0.26 mag]0.60 (28)
R [0.21 mag]0.83 (25)0.54 (19)
I [0.17 mag]0.57 (19)0.08 (10)0.21 (7)

Magnitude-Magnitude Plots

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

Plot to assess correlation between bands for M31-004021.21

Plot to assess correlation between bands for M31-004021.21

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)
1.15 | 0.89
R
(I|R)
0.81 | 1.030.33 | 0.06
I
(I|R)
0.54 | 1.560.24 | 1.220.49 | 1.56

Back to catalog index


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

Generated on 2021-11-06 16:53:54 UT-5