TESS Data Release Notes

As the TESS mission has evolved, so has the processing and delivery of its data. Whilst a data release note (DRN) is provided for every sector of the mission, this page highlights important changes that might affect you, the user, and your handling/understanding of the data.

Key updates

Below we outline some of the most important issues or data product modifications. For more details please see the Sector tables provided below, and the DRNs listed within.

  • Reprocessing of Sectors 1-13 (May 2021):

    • In Sector 2 the instrument electronics model Reference Flux was been updated. The first two overclock rows were also removed from the calculation of the 1D bias correction in the CAL module.
    • In Sector 8 the instrument PRF model was updated. The updated PRF model corresponds to improved performance in the spacecraft’s Attitude Control System starting in Sector 4. Note that Sectors 1–3 were also reprocessed with this model.
    • In Sector 5 the parameters to calibrate PDC goodness metrics were finalized in the PDC module.
    • Targets from Sectors 1–13 were reprocessed with version 8 of the TESS Input Catalog(TIC), consistent with Sectors 14–36. TIC 8 is based on Gaia DR2 rather than 2MASS, and includes significantly more stars and improved stellar parameters. The change in TIC version affects the apertures assigned to individual targets, the calculations of crowding and flux fraction reported in the CROWDSAP and FLUXFRAC keywords, and the physical properties of TCEs derived from stellar parameters.
    • The timestamps for data from Sectors 1-13 have been updated. All data from Sector 1–36 are now reported in a consistent time system.
    • New data flags were applied to Sectors 1-13 consistent with those described in DRN30.These flags are primarily used to mitigate the effects of scattered light. They are applied per target rather than per CCD, and improve the contrending and planet search for the reprocessed data.
    • All ”Manual Exclude” flags are now set in a consistent way for the reprocessed data, using a pointing excursion threshold of 7 arcseconds measured from the spacecraft’s fine pointing system.
    • The planet search of the reprocessed light curves produced a different set of TCEs from the original processed data. Although there is a high degree of overlap between the original and reprocessed data, new TCEs were produced in DR42 and DR46, and not every TCE from previous data releases was recovered. To differentiate between the initial release and this reprocessed data a "pipeline instance number" is included in the filenames of the dv-timeseries, dv-reports, ad dv-result xml files. Larger pin numbers indicate later versions of the software were used to produce the data products. The DR number is also included as a keyword in the export product headers (DATAREL).
    • An updated sky background correction algorithm was applied to Sectors 1-13

  • Sector 32 (January 2021): Approximately 26 hrs lost due to a star tracker anomaly.

  • Sector 31 (December 2020): Approximately 4 days lost due to a star tracker anomaly.

  • Sector 30 (November 2020): As of Sector 30, co-trending basis vector (CBV) files only include the first eight principal components for the Single Scale co-trending mode.

  • Sector 27 (September 2020): This is the first data release for the extended mission. Key changes have occurred including the collection of 10-min FFI data instead of 30-min, and 20-second target pixel files.

    The background correction was updated for the extended mission, with the new method providing improved results for fainter and crowded stars.

    For targets observed in both Year 1 and Year 3, Year 3 processing was done using TIC 8.1 while TIC 7 was used for Year 1 processing; this may result in differences in results for certain targets.

Key update archive »

Quick look mission information

Information

Year Hemisphere Dates (UTC)

Start - End

Sectors Mission
1 Southern 07/25/18 - 07/18/19 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13 Prime
2 Northern 07/18/19 - 07/04/20 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26 Prime
3 Southern 07/04/20 - 06/24/21 27, 28, 29, 20, 31, 32, 33, 34, 35, 36, 37, 38, 39 Extended
4 Northern 06/24/21 - 09/01/22 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52 53 54 55 Extended

Cycle 3 DRN Tables

Below we provide a brief summary of the DRNs for each Sector in Cycle 3.

Sector 34

Information

DRN Orbits Dates (UTC)

Start - End

Cadence #

Start - End

Data pause

(days)

Science data (days) Momentum dumps Problematic

TIC ID's

50

75

76

2021-01-14 - 2021-01-26

2021-01-27 - 2021-02-08

720929 - 729684

730459 - 739159

1.08 24.24

1

1

list
Issue Description
Spacecraft pointing: Camera 1 and Camera 4 were both used for guiding in orbit 75 of Sector 34. Camera 4 alone was used for guiding in orbit 76.

Sector 33

Information

DRN Orbits Dates (UTC)

Start - End

Cadence #

Start - End

Data pause

(days)

Science data (days) Momentum dumps Problematic

TIC ID's

49

73

74

2020-12-18 -- 2020-12-30

2020-12-31 -- 2021-01-13

701476 -- 710214

711341 -- 7720084

1.57 24.23

1

1

list
Issue Description
Scattered light: In Sector 33, the Moon introduces a strong glint in Camera 1 at the end of orbit 73.
Big update:

As of Sector 30, co-trending basis vector (CBV) files only include the first eight principal components for the Single Scale co-trending mode.

As a reminder, the pipeline only uses the first eight CBVs for co-trending, because subsequent CBVs are usually dominated by stochastic noise. When using CBVs beyond 8, users should check for excess noise being introduced into the detrended light curve

In Sectors 30–33, the values for CBVs 9–16 are set to 0.

Sector 32

Information

DRN Orbits Dates (UTC)

Start - End

Cadence #

Start - End

Data pause

(days)

Science data (days) Momentum dumps Problematic

TIC ID's

48

71

72

2020-11-20 -- 2020-12-02

2020-12-03 -- 2020-12-16

681670 -- 690109

690829 -- 700399

1.0 25.01

1

1

list
Issue Description
Star tracker anomaly: UTC 2020-11-16 10:37, instrument turned off and collection of data for orbit 71 started 29 hrs later than scheduled. Normal operation started 2020-11-20-17-13-00 UTC.
Spacecraft pointing: Camera 4 alone was used for guiding in orbit 72.
Scattered light: In Sector 32, the Moon introduces a strong glint in Camera 1 at the end of orbit 71.

Sector 31

Information

DRN Orbits Dates (UTC)

Start - End

Cadence #

Start - End

Data pause

(days)

Science data (days) Momentum dumps Problematic

TIC ID's

47

69

70

2020-10-22 -- 2020-11-03

2020-11-05 -- 2020-11-16

660279 -- 669599

670609 -- 678592

1.4 24.03

1

1

list
Issue Description
Star tracker anomaly: At UTC 2020-11-16 10:37, there was a star tracker anomaly which led to the instrument being turned off. As a result, the data collection period in orbit 70 ended 2.08 days earlier than scheduled. The cameras were turned on and returned to normal operations on 2020-11-20, at the beginning of Sector 32.
Spacecraft pointing: Camera 1 suffered from strong scattered light signals at the end of orbit 69 and orbit 70, and so Camera 4 alone was used for guiding during this sector.
Scattered light: In Sector 31, the Moon introduces a strong glint in Camera 1 at the end of orbit 69, followed by scattered light signals in all cameras caused by the Earth. Due to the star tracker anomaly, no data were taken during periods of high scattered light in orbit 70.

Sector 30

Information

DRN Orbits Dates (UTC)

Start - End

Cadence #

Start - End

Data pause

(days)

Science data (days) Momentum dumps Problematic

TIC ID's

45

67

68

2020-09-23 -- 2020-10-06

2020-10-07 -- 2020-10-20

639666 -- 649212

649979 -- 659352

1.07 26.28

1

1

list
Issue Description
Spacecraft pointing: Camera 1 suffered from strong scattered light signals at the end of orbit 67 and orbit 68, and so Camera 4 alone was used for guiding during this sector.
Scattered light: In Sector 30, the Moon introduces a strong glint in Camera 1 at the end of orbit 67, and the Earth introduces scattered light signals in all cameras at the end of both orbits.

Sector 29

Information

DRN Orbits Dates (UTC)

Start - End

Cadence #

Start - End

Data pause

(days)

Science data (days) Momentum dumps Problematic

TIC ID's

43

65

66

2020-08-26 -- 2020-09-08

2020-09-09 -- 2020-09-21

619761 -- 629222

629904 -- 638624

0.95 25.25

1

1

list
Issue Description
Spacecraft pointing: Camera 1 suffered from strong scattered light signals at the end of orbit 65 and orbit 66, and so Camera 4 alone was used for guiding during this sector.
Scattered light: In Sector 29, the Moon introduces a strong glint in Camera 1 at the end of orbit 65, and the Earth introduces scattered light signals in all cameras at the end of both orbits.

Sector 28

Information

DRN Orbits Dates (UTC)

Start - End

Cadence #

Start - End

Data pause

(days)

Science data (days) Momentum dumps Problematic

TIC ID's

41

63

64

2020-07-31 -- 2020-08-12

2020-08-13 -- 2020-08-25

600761 -- 609484

610341 -- 618942

1.19 24.06

1

1

list
Issue Description
Scattered light: In Sector 28, the Earth introduces scattered light signals at the end of both orbits.

Sector 27

Information

DRN Orbits Dates (UTC)

Start - End

Cadence #

Start - End

Data pause

(days)

Science data (days) Momentum dumps Problematic

TIC ID's

38

61

62

2020-07-05 -- 2020-07-17

2020-07-18 -- 2020-07-30

582349 -- 590884

591619 -- 599894

1.02 23.35

1

1

list
Issue Description
Spacecraft pointing: Year 3 is a re-observation of the southern ecliptic hemisphere, which will take place over 13 sectors. The pointing strategy is the same as for Year 1, except the locations of Sectors 27–39 are offset in ecliptic longitude with respect to Sectors 1–13. All sectors in Year 3 are planned for a spacecraft pointing of −54 degrees in ecliptic latitude.
Scattered light: In Sector 27, the Earth is a significant source of scattered light throughout both orbits.

Big Updates!

This is the first data release for the extended mission

FFI data is collected every 10 min, rather than 30.

Selected pixel stamps are collected at a 20-sec cadence.

Data products for the 20 second mode have the keyword "fast" in the file names.

For 20-second data, only target pixel files, light curve files, collateral pixel files, and co-trending basis vectors (CBVs) were produced.

As usual cosmic rays were mitigated in the 2-minute cadence data and 10-minute FFIs by an algorithm running on the instrument firmware - see DRN pg. 8, for more info. Note however, that in the new 20-second pixel data cosmic rays were identified and removed in the pipeline, and that they can be restored in the pixel data and light curves if necessary.

The background correction employed throughout the primary mission was updated for the extended mission. The new method provides improved results for fainter and crowded stars. The correction is applied only to 2-min and 20-sec data. A full explanation of this correction is on pg. 10 of the DRN

For targets observed in both Year 1 and Year 3, Year 3 processing was done using TIC 8.1 while TIC 7 was used for Year 1 processing; this may result in different results for certain targets. Differences for some crowded and/or dim targets may also result from the background correction algorithm update (see below). Reprocessing of Year 1 data with TIC 8.1 and the latest codebase is underway at the SPOC, as of Fall 2020.

The algorithm in the CAL module that propagates uncertainty from the 2D bias model was changed. This uncertainty is a static term and is no longer applied to the pixel data or subsequent processing in the pipeline.

The algorithm in the PA module that estimates the sky background was changed. A scalar offset is now applied that forces the dimmest background-corrected pixels to values near zero, if those pixels were significantly negative.

Cycle 2 DRN Tables

Below we provide a brief summary of the DRNs for each Sector in Cycle 2.

Cycle 2 Tables »

Cycle 1 DRN Tables

Below we provide a brief summary of the DRNs for each Sector in Cycle 1.

Cycle 1 Tables »

Below we list some potentially useful urls for those users wishing to learn more about TESS (and Kepler) data processing.