T Pyx - recurrent nova

Monitored source

Position: 09:04:41.51 -32:22:47.6
Cameras: TTUQ1b1x1 TTUQ2b1x1
Measurements: 0 detections, 37 upper limits, 2 excluded from the lightcurve
Date range: 2026-01-09.35666 .. 2026-11-03.48226 (UTC)
JD range: 2461049.85666 .. 2461347.98226

Manual detection threshold: measurements fainter than mag 14.20 are published as upper limits at the measured magnitude, because the photometric aperture is contaminated by light from an unrelated nearby source. Below that threshold a measurement only bounds the target brightness from above; only when the target outshines the contaminant does a measurement count as a detection (status below_threshold in the table below marks the demoted measurements).

Lightcurve - last 30 days

Lightcurve - full time range

Data files: lightcurve.dat (JD mag err camera field) · upperlimits.dat (JD limit_mag camera field) · lightcurve_aavso.txt (AAVSO Extended Format incl. fainter-than records)

Why these photometric measurements are not very precise

Photometric measurements obtained with a wide-field camera are not very precise, for a number of reasons:

Bad plate solution: errors in the astrometric calibration result in misplacement of the photometric aperture. This may create outlier measurements.
Undersampled PSF: star images occupy only a few pixels, so any uncorrected pixel-to-pixel and intra-pixel sensitivity variations affect the measurements more than they would for well-sampled telescopic images in which each star is spread across many pixels.
Low observing altitude: the fields are often imaged only 15-20 degrees above the horizon. This is a deliberate trade-off for an all-sky transient search, as the sky area at low elevation is far larger than the area near the zenith, but it is bad for photometric accuracy. An airmass-dependent magnitude zero-point correction is applied, but it is not perfect.
Color-dependent (second-order) extinction: a star's brightness measured relative to the comparison stars in the field is elevation-dependent if the star's color differs from the average color of the comparison stars.
Blending with nearby stars in crowded fields affects the measurements differently depending on the aperture size, which is adjusted for each image individually based on the seeing and focus quality.
Position-dependent PSF: the same star may fall closer to the image center in one field and farther from it in another, so a different fraction of its PSF is covered by the aperture even when the same aperture is used to measure both images. Field-to-field and camera-to-camera calibration is therefore an issue, and its magnitude differs from source to source.
Chromatic aberration: many wide-field lenses suffer from it, leaving extremely red stars out of focus while the focus is optimal for average-colored stars.
Clouds, if present, dramatically degrade the quality of the photometry across the entire image.

In practice, expect a photometric uncertainty of ~0.1 mag, or somewhat better in favorable conditions.

The intended use of these data is a quick check of the current state of a source (flaring or quiescent) - not precise photometry.

The photometric measurements are performed without a filter; the zero-point of the instrumental magnitude scale is set by the V magnitudes of the field stars. You are welcome to use these data in any way you see fit, providing a link to this page as the origin of the data.

Photometry table (newest measurements first)

Date (UTC)       JD(UTC)           mag     err      status      camera      image
2026-11-03.48226 2461347.98225797  14.6760 99.0000  upperlimit  TTUQ1b1x1   wcs_fd_Pyx-02-Q1b1x1_2026-11-03_05-34-17_20.00sec_0.00C_LIGHTs_0558.fits
2026-11-03.48170 2461347.98169601  14.6850 99.0000  upperlimit  TTUQ1b1x1   wcs_fd_Pyx-02-Q1b1x1_2026-11-03_05-33-28_20.00sec_-0.00C_LIGHTs_0557.fits
2026-11-03.46147 2461347.96147366  14.6739 99.0000  upperlimit  TTUQ2b1x1   wcs_fd_Pyx-02-Q2b1x1_2026-11-03_05-04-21_20.00sec_-0.00C_LIGHT_0545.fits
2026-11-03.46094 2461347.96094231  14.6635 99.0000  upperlimit  TTUQ2b1x1   wcs_fd_Pyx-02-Q2b1x1_2026-11-03_05-03-35_20.00sec_0.00C_LIGHT_0544.fits
2026-04-19.13407 2461149.63406794  14.7654 99.0000  upperlimit  TTUQ2b1x1   wcs_fd_Pyx-02-Q2b1x1_2026-04-18_22-12-53_20.00sec_-5.00C_LIGHT_0393.fits
2026-04-16.13330 2461146.63329824  14.9136 99.0000  upperlimit  TTUQ2b1x1   wcs_fd_Pyx-02-Q2b1x1_2026-04-15_22-11-46_20.00sec_-5.00C_LIGHT_0078.fits
2026-04-16.13266 2461146.63266470  14.8790 99.0000  upperlimit  TTUQ2b1x1   wcs_fd_Pyx-02-Q2b1x1_2026-04-15_22-10-52_20.00sec_-5.00C_LIGHT_0077.fits
2026-04-09.14422 2461139.64421522  14.7553 99.0000  upperlimit  TTUQ2b1x1   wcs_fd_Pyx-02-Q2b1x1_2026-04-08_22-27-30_20.00sec_-4.90C_LIGHT_0095.fits
2026-04-09.14358 2461139.64358051  14.7498 99.0000  upperlimit  TTUQ2b1x1   wcs_fd_Pyx-02-Q2b1x1_2026-04-08_22-26-35_20.00sec_-4.90C_LIGHT_0094.fits
2026-04-06.14422 2461136.64421723  14.8937 99.0000  upperlimit  TTUQ2b1x1   wcs_fd_Pyx-02-Q2b1x1_2026-04-05_22-27-30_20.00sec_-4.90C_LIGHT_0077.fits
2026-04-06.14365 2461136.64365175  14.9208 99.0000  upperlimit  TTUQ2b1x1   wcs_fd_Pyx-02-Q2b1x1_2026-04-05_22-26-41_20.00sec_-4.90C_LIGHT_0076.fits
2026-03-29.14486 2461128.64486295  14.2717 99.0000  upperlimit  TTUQ2b1x1   wcs_fd_Pyx-02-Q2b1x1_2026-03-28_22-28-26_20.00sec_-15.00C_LIGHT_0098.fits
2026-03-29.14427 2461128.64427316  14.2561 99.0000  upperlimit  TTUQ2b1x1   wcs_fd_Pyx-02-Q2b1x1_2026-03-28_22-27-35_20.00sec_-14.90C_LIGHT_0097.fits
2026-03-27.14725 2461126.64724551  14.4299 99.0000  upperlimit  TTUQ2b1x1   wcs_fd_Pyx-02-Q2b1x1_2026-03-26_22-31-52_20.00sec_-10.00C_LIGHT_0093.fits
2026-03-27.14463 2461126.64463483  14.2659 99.0000  upperlimit  TTUQ2b1x1   wcs_fd_Pyx-02-Q2b1x1_2026-03-26_22-28-06_20.00sec_-10.00C_LIGHT_0092.fits
2026-03-26.12954 2461125.62954145  14.3567 99.0000  upperlimit  TTUQ2b1x1   wcs_fd_Pyx-02-Q2b1x1_2026-03-25_22-06-22_20.00sec_-10.00C_LIGHT_0317.fits
2026-03-26.12900 2461125.62900057  14.3498 99.0000  upperlimit  TTUQ2b1x1   wcs_fd_Pyx-02-Q2b1x1_2026-03-25_22-05-35_20.00sec_-10.00C_LIGHT_0316.fits
2026-03-22.19119 2461121.69118697  14.9680 99.0000  upperlimit  TTUQ2b1x1   wcs_fd_Pyx-02-Q2b1x1_2026-03-21_23-35-08_20.00sec_-15.00C_LIGHT_0049.fits
2026-03-22.19058 2461121.69057841  14.9763 99.0000  upperlimit  TTUQ2b1x1   wcs_fd_Pyx-02-Q2b1x1_2026-03-21_23-34-15_20.00sec_-15.00C_LIGHT_0048.fits
2026-03-21.15387 2461120.65386777  14.7694 99.0000  upperlimit  TTUQ2b1x1   wcs_fd_Pyx-02-Q2b1x1_2026-03-20_22-41-24_20.00sec_-15.00C_LIGHT_0116.fits
2026-03-21.15334 2461120.65334087  14.7910 99.0000  upperlimit  TTUQ2b1x1   wcs_fd_Pyx-02-Q2b1x1_2026-03-20_22-40-38_20.00sec_-14.90C_LIGHT_0115.fits
2026-02-27.21075 2461098.71075302  14.4653 99.0000  upperlimit  TTUQ2b1x1   wcs_fd_Pyx-02-Q2b1x1_2026-02-26_23-03-19_20.00sec_-15.00C_LIGHT_0041.fits
2026-02-27.21026 2461098.71025672  14.4411 99.0000  upperlimit  TTUQ2b1x1   wcs_fd_Pyx-02-Q2b1x1_2026-02-26_23-02-36_20.00sec_-14.90C_LIGHT_0040.fits
2026-02-22.19807 2461093.69807112  14.5510 99.0000  upperlimit  TTUQ2b1x1   wcs_fd_Pyx-02-Q2b1x1_2026-02-21_22-45-03_20.00sec_-14.90C_LIGHT_0124.fits
2026-02-22.19757 2461093.69756784  14.6071 99.0000  upperlimit  TTUQ2b1x1   wcs_fd_Pyx-02-Q2b1x1_2026-02-21_22-44-19_20.00sec_-15.00C_LIGHT_0123.fits
2026-02-22.17077 2461093.67077113  14.6608 99.0000  upperlimit  TTUQ1b1x1   wcs_fd_Pyx-02-Q1b1x1_2026-02-21_22-05-44_20.00sec_-14.90C_LIGHT_0130.fits
2026-02-22.16994 2461093.66994439  14.6704 99.0000  upperlimit  TTUQ1b1x1   wcs_fd_Pyx-02-Q1b1x1_2026-02-21_22-04-33_20.00sec_-14.90C_LIGHT_0129.fits
2026-02-12.18609 2461083.68609096  14.6613 99.0000  upperlimit  TTUQ1b1x1   wcs_fd_Pyx-02-Q1b1x1_2026-02-11_22-27-48_20.00sec_-15.00C_LIGHT_0156.fits
2026-02-12.18564 2461083.68563560  14.6858 99.0000  upperlimit  TTUQ1b1x1   wcs_fd_Pyx-02-Q1b1x1_2026-02-11_22-27-08_20.00sec_-14.90C_LIGHT_0155.fits
2026-02-11.20802 2461082.70802231  14.6816 99.0000  upperlimit  TTUQ1b1x1   wcs_fd_Pyx-02-Q1b1x1_2026-02-10_22-59-23_20.00sec_-15.00C_LIGHT_0168.fits
2026-02-11.20736 2461082.70736433  14.6669 99.0000  upperlimit  TTUQ1b1x1   wcs_fd_Pyx-02-Q1b1x1_2026-02-10_22-58-26_20.00sec_-15.00C_LIGHT_0167.fits
2026-01-21.24636 2461061.74635965  14.6102 99.0000  upperlimit  TTUQ1b1x1   wcs_fd_Pyx-02-Q1b1x1_2026-01-20_23-54-35_20.00sec_-15.00C_LIGHT_0274.fits
2026-01-21.24554 2461061.74554441  14.6185 99.0000  upperlimit  TTUQ1b1x1   wcs_fd_Pyx-02-Q1b1x1_2026-01-20_23-53-25_20.00sec_-15.00C_LIGHT_0273.fits
2026-01-18.24079 2461058.74078767  14.4817 99.0000  upperlimit  TTUQ1b1x1   wcs_fd_Pyx-02-Q1b1x1_2026-01-17_23-46-34_20.00sec_-14.90C_LIGHT_0234.fits
2026-01-18.24022 2461058.74021918  14.4715 99.0000  upperlimit  TTUQ1b1x1   wcs_fd_Pyx-02-Q1b1x1_2026-01-17_23-45-44_20.00sec_-15.00C_LIGHT_0233.fits
2026-01-09.35724 2461049.85724322  14.8602 99.0000  upperlimit  TTUQ1b1x1   wcs_fd_Pyx-02-Q1b1x1_2026-01-09_02-34-15_20.00sec_-15.00C_LIGHT_0011.fits
2026-01-09.35666 2461049.85665904  14.8554 99.0000  upperlimit  TTUQ1b1x1   wcs_fd_Pyx-02-Q1b1x1_2026-01-09_02-33-25_20.00sec_-14.90C_LIGHT_0010.fits

Measurements excluded from the lightcurve

These measurements are excluded from the lightcurve, the plot and the AAVSO file. Reason visit_inconsistent: frames of the same field taken minutes apart disagree by more than the expected measurement scatter - a real star cannot change that fast, so at least one frame of the visit is corrupted (typically by patchy clouds) and there is no way to tell which one. Reason cloudy_frame: the frame failed the cloud check - its field stars disagree with the reference frame in a way uniform transparency loss cannot explain; a frame condemned while measuring one source is excluded for every source measured on it later. The next five reasons mean the measurement could not be made on that image at all, so no magnitude is shown: bad_ccd_region - the position falls on a masked part of the detector (bad_region.lst of that camera); saturated - the star is there but too bright to measure; blank_pixels_in_aperture, magnitude_calibration_failed and measurement_failed - the aperture contained blank pixels, the frame could not be calibrated, or the measuring tool failed. These images WERE taken and WERE measured: they are listed here so that a rejected measurement is never mistaken for a gap in the coverage. Three more reasons reject a measurement that was or could have been made, so a magnitude may be shown, but it means nothing: processing_error_in_run - the transient search run that processed the image raised a processing error or failed, so none of its measurements is used; unreliable_plate_solution - the image was plate-solved without a distortion polynomial, so away from the frame centre the aperture may be tens of arcseconds off the source; no_stars_around_position - (almost) no stars were detected within half a degree of the position on a frame rich enough in stars to expect dozens there, typically a thick cloud over the source. The excluded rows are kept in excluded_measurements.dat.

Date (UTC)       JD(UTC)           mag     err      reason                       camera      image
2026-10-19.50255 2461333.00255324  13.9580 99.0000  cloudy_frame                 TTUQ2b1x1   wcs_fd_Pyx-02-Q2b1x1_2026-10-19_07-03-30_20.00sec_0.00C_LIGHT_0643.fits
2026-10-19.50190 2461333.00189828  13.9174 99.0000  cloudy_frame                 TTUQ2b1x1   wcs_fd_Pyx-02-Q2b1x1_2026-10-19_07-02-34_20.00sec_-0.00C_LIGHT_0642.fits