Color composite thumbnail image of M31-004221.78M31-004221.78 (J004221.78+410013.4)



Target Notes

Color composite thumbnail image of M31-004221.78

Classification: B[e]sg

In the wings of a foreground star that is five magnitudes brighter. In R in particular daophot struggles to make any fit.

Find In Simbad Query LGGS Massey (2016) at VizieR Query CAT WISE (Eisenhardt et al., 2020) at VizieR Query Gaia EDR3 (2020) 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
MJDV*ImageB*ImageR*ImagesI*Images
56142.34>19.240-M31-004221.78 in filter V on MJD  56142.340
------------
56267.16-------- 18.20± 0.05-M31-004221.78 in filter R on MJD  56267.160
----
56537.17 19.55± 0.15TM31-004221.78 in filter V on MJD  56537.170
> 18.80-M31-004221.78 in filter B on MJD  56537.170
18.32± 0.07-M31-004221.78 in filter R on MJD  56537.170
----
56930.14 19.40± 0.12TM31-004221.78 in filter V on MJD  56930.140
> 18.73-M31-004221.78 in filter B on MJD  56930.140
18.26± 0.06-M31-004221.78 in filter R on MJD  56930.140
----
57285.24 19.47± 0.10TM31-004221.78 in filter V on MJD  57285.240
> 19.15-M31-004221.78 in filter B on MJD  57285.240
18.24± 0.06-M31-004221.78 in filter R on MJD  57285.240
----
57340.19>19.410-M31-004221.78 in filter V on MJD  57340.190
-------- 19.16± 0.26TM31-004221.78 in filter I on MJD  57340.190
57633.38>19.380-M31-004221.78 in filter V on MJD  57633.380
> 19.09-M31-004221.78 in filter B on MJD  57633.380
18.49± 0.05-M31-004221.78 in filter R on MJD  57633.380
----
57635.27 19.36± 0.11-M31-004221.78 in filter V on MJD  57635.270
19.94± 0.12-M31-004221.78 in filter B on MJD  57635.270
18.26± 0.06-M31-004221.78 in filter R on MJD  57635.270
18.34± 0.09-M31-004221.78 in filter I on MJD  57635.270
57659.15 19.71± 0.18-M31-004221.78 in filter V on MJD  57659.150
-------- 18.72± 0.17-M31-004221.78 in filter I on MJD  57659.150
57687.09 19.26± 0.10-M31-004221.78 in filter V on MJD  57687.090
> 19.03-M31-004221.78 in filter B on MJD  57687.090
18.36± 0.07-M31-004221.78 in filter R on MJD  57687.090
18.35± 0.12-M31-004221.78 in filter I on MJD  57687.090
57958.40 19.31± 0.10TM31-004221.78 in filter V on MJD  57958.400
--------> 18.44-M31-004221.78 in filter I on MJD  57958.400
57963.41 19.56± 0.11-M31-004221.78 in filter V on MJD  57963.410
> 19.09-M31-004221.78 in filter B on MJD  57963.410
18.39± 0.07-M31-004221.78 in filter R on MJD  57963.410
----
57988.26 19.50± 0.09-M31-004221.78 in filter V on MJD  57988.260
19.87± 0.13-M31-004221.78 in filter B on MJD  57988.260
18.36± 0.06-M31-004221.78 in filter R on MJD  57988.260
----
58067.16>19.410-M31-004221.78 in filter V on MJD  58067.160
-------- 18.86± 0.12-M31-004221.78 in filter I on MJD  58067.160
58098.14 19.70± 0.10-M31-004221.78 in filter V on MJD  58098.140
19.79± 0.10-M31-004221.78 in filter B on MJD  58098.140
--------
58317.28 19.63± 0.14-M31-004221.78 in filter V on MJD  58317.280
20.12± 0.18-M31-004221.78 in filter B on MJD  58317.280
18.46± 0.07-M31-004221.78 in filter R on MJD  58317.280
----
58339.27 19.93± 0.12-M31-004221.78 in filter V on MJD  58339.270
-------- 18.77± 0.13-M31-004221.78 in filter I on MJD  58339.270
58342.27 19.64± 0.15TM31-004221.78 in filter V on MJD  58342.270
> 18.52-M31-004221.78 in filter B on MJD  58342.270
--------
58373.09>19.100-M31-004221.78 in filter V on MJD  58373.090
> 18.70-M31-004221.78 in filter B on MJD  58373.090
--------
58671.35 19.47± 0.12AM31-004221.78 in filter V on MJD  58671.350
M31-004221.78 in filter V on MJD  58671.350
20.16± 0.14-M31-004221.78 in filter B on MJD  58671.350
18.41± 0.05-M31-004221.78 in filter R on MJD  58671.350
----
58673.32 19.76± 0.08-M31-004221.78 in filter V on MJD  58673.320
20.30± 0.13-M31-004221.78 in filter B on MJD  58673.320
--------
58750.16 19.50± 0.07-M31-004221.78 in filter V on MJD  58750.160
---- 18.46± 0.05-M31-004221.78 in filter R on MJD  58750.160
18.62± 0.10-M31-004221.78 in filter I on MJD  58750.160
58784.10 19.79± 0.07-M31-004221.78 in filter V on MJD  58784.100
20.14± 0.10-M31-004221.78 in filter B on MJD  58784.100
--------
58836.15>19.320-M31-004221.78 in filter V on MJD  58836.150
---- 18.53± 0.08TM31-004221.78 in filter R on MJD  58836.150
18.79± 0.12TM31-004221.78 in filter I on MJD  58836.150
59026.38 19.70± 0.09-M31-004221.78 in filter V on MJD  59026.380
> 19.00-M31-004221.78 in filter B on MJD  59026.380
18.48± 0.06-M31-004221.78 in filter R on MJD  59026.380
----
59056.27 19.79± 0.12-M31-004221.78 in filter V on MJD  59056.270
19.87± 0.11-M31-004221.78 in filter B on MJD  59056.270
---- 18.78± 0.11-M31-004221.78 in filter I on MJD  59056.270
59077.27 19.75± 0.09-M31-004221.78 in filter V on MJD  59077.270
---- 18.43± 0.06-M31-004221.78 in filter R on MJD  59077.270
18.57± 0.09-M31-004221.78 in filter I on MJD  59077.270
59082.24 19.78± 0.11-M31-004221.78 in filter V on MJD  59082.240
19.95± 0.13-M31-004221.78 in filter B on MJD  59082.240
--------
59136.06 20.05± 0.21-M31-004221.78 in filter V on MJD  59136.060
---- 18.64± 0.10-M31-004221.78 in filter R on MJD  59136.060
----
59166.16 19.58± 0.08-M31-004221.78 in filter V on MJD  59166.160
-------- 18.54± 0.09-M31-004221.78 in filter I on MJD  59166.160
59382.34 19.69± 0.28TM31-004221.78 in filter V on MJD  59382.340
> 17.97-M31-004221.78 in filter B on MJD  59382.340
--------
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 M31-004221.78Plot of color for M31-004221.78

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 [0.00 mag]B [0.79 mag]R [0.44 mag]
B [0.00 mag]0.01 (9)
R [0.44 mag]0.65 (13)0.52 (4)
I [0.82 mag]0.80 (8)-.-- (2) 0.89 (5)

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 M31-004221.78

Plot to assess correlation between bands for M31-004221.78

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)
0.52 | 0.90
R
(I|R)
1.62 | 0.90--- | ---
I
(I|R)
2.62 | 1.40--- | --- 2.54 | 0.90

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