GOME-2 level 1: calibrated radiances from two Metops – slit function performance, signal forecasts and EoL activities Rűdiger Lang, Rose Munro, Antoine.

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Presentation transcript:

GOME-2 level 1: calibrated radiances from two Metops – slit function performance, signal forecasts and EoL activities Rűdiger Lang, Rose Munro, Antoine Lacan, Christian Retscher, Gabriele Poli, Michael Grzegorski, Alexander Kokhanovski, Ed Trollope and Richard Dyer EUMETSAT

Outline Slit-function performance and change Update on instrument degradation Degradation Forecast End of orbit maintenance: loss of solar visibility scenarios Metop-A End-of-Life

The GOME-2 instrument on Metop Measuring atmospheric composition Wavelength [nm] GOME-2 main channel transmittance Aerosol O3 HCHO SO2 BrO OClO NO2 (O2)2 H2O O2 I/I0 GOME-2: series of 3 instruments on Metop (Metop A launched in 10/2006) sun-synchronous orbit, 09:30 412 orbits (29 days) repeat cycle Global coverage 1.5 days 240 nm to 800 nm 0.25 to 0. 5 nm spectral resolution (FWHM) 4 channels with 4098 energy measurements of polarisation corrected radiances (40 x 80 km2) 2 channels with 512 energy measurements of linear polarised light in perpendicular direction (S/P) (40 x 10 km2) Orbit file sizes GOME-2 L1B ~ 1GB IASI L1C ~ 2GB

GOME-2 optical layout Scanning grating spectrometer with a random-access linear silicon photodiode array

Timelines for the Metop / GOME-2 level 1 products Processor versions: Reprocessed and NRT data Release of second set of reprocessed level 1 data (R2) from Metop-A GOME-2 in August 2012 (Covering: 25th January 2007 to 25th January 2012) Metop-B with GOME-2 flight-model 2 (FM2) launched in-orbit 17th September 2012 Metop-A GOME-2 will continue until launch of Metop-C (October 2017) Oct 2018 Today Sep 2012 Jan 2012 Jan 2007 Metop-A / GOME-2 level 1 processor version 5.3.0 Metop-B / GOME-2 version 5.3.0 Future NRT versions TBD Metop-C / GOME-2 Future NRT version R2 Metop-A Metop-B Metop-C

Slit function characterization – FM3/Metop-A FWHM FM3 from on-board spectral light source – Stability in time GOME-2 FM3 Metop-A Is this and an effect of thermal environment changes, or due to throughput degradation? Hypothesis: slowly decreasing FWHM due to thermal changes and throughput degradation.

Slit function characterization – FM3/Metop-A Degradation study IUP Bremen (Dikty/Richter) GOME-2 FM3 Metop-A In calibration of GOME-2 solar spectra on Kurucz Fraunhofer atlas the FWHM (of a Gaussian slit function) is also fitted FWHM changes consistently over channel 2 FWHM decreases over time No effect of throughput test

Slit function characterization – FM2/Metop-B Comparison Slit-function FWHM on-ground/in-orbit (29th October 2012) GOME-2 FM2 Metop-B

Slit function characterization – FM2/Metop-B FWHM FM2 from on-board spectral light source – Stability in time GOME-2 FM2 Metop-B

Slit function characterization – FM2/FM3 FWHM FM2/FM3 from on-board spectral light source – Stability in time GOME-2 FM3 Metop-A GOME-2 FM2 Metop-B Metop-B / FM2 Metop-A / FM3

Slit function characterization – FM2/FM3 FWHM FM2/FM3 from on-board spectral light source – Long-term stability in time GOME-2 FM3 Metop-A GOME-2 FM2 Metop-B Metop-A / FM3 Metop-B / FM2 OB temperature (ONA0281) GOME-2 /Metop-B OB temperature GOME-2 /Metop-A

Courtesy, A. Richter, IUP, Univ. Bremen Slit function characterization – FM2 FWHM FM2 from on-board spectral light source – orbital variation GOME-2 FM2 Metop-B Change of FWHM along the orbit at 455 nm for Metop-B / FM2. Courtesy, A. Richter, IUP, Univ. Bremen Optical bench temperature change along one orbit for Metop-B / FM2.

Slit function characterization – FM2/FM3 Impact on level 2 products GOME-2 FM3 Metop-A GOME-2 FM2 Metop-B When introducing an empirical correction for the orbital change of the spectral resolution (FWHM) one can flatten out the currently observed RMS fit values. Courtesy Faiza and Richter, UIP Bremen

Slit function characterization – FM2/FM3 Preliminary conclusions GOME-2 FM3 Metop-A GOME-2 FM2 Metop-B The change in spectral resolution, as observed via the FWHM from spectral light source lines and Fraunhofer lines, is highly correlated with the change in the optical bench temperatures at all time scales: long-term, seasonal, orbital For the seasonal and orbital variations the optical bench temperature and the FWHM are highly, positively correlated, i.e. for an decreasing OB temperature we observe a decreasing FWHM. For the long-term temperature change, however, the FWHM change and the OB temperature change are anit-corelated. Independent of the sign of the correlation, a changing spectral resolution may have a substantial effect on the level-2 retrieval quality depending on the spectral region and the absorber

Slit function characterization – FM2/Metop-B Commissioning level-1b – level-2 fit results GOME-2 FM2 Metop-B Fit residual peaks near 316 and 323 nm for RAL slit functions reported by KNMI - potentially introduced by ghost fitting procedure (TBC) Not present in TNO key-data slit functions

Is signal degradation a problem? – Yes, but.... GOME-2 / Metop-A degradation Impact on level-2 products GOME-2 FM3 Metop-A Degradation predominantly affects fit residuals and scatter Retrieved values are less or not affected Fitting residuals increase over time Effect is largest in channel 2, but NO2 is also affected The same is true for other absorbers (SO2, HCHO, CHOCHO) All operational products of GOME-2 / Metop-A are still within specifications Is signal degradation a problem? – Yes, but.... Study by: S. Dikty and A. Richter, IUP Bremen See Level 2 report on the impact of degradation on level 2 products: www.eumetsat.int > Data & Products > Resources > EPS Product Validation Reports

Do we have an Etalon correction problem? Instrument degradation (Metop-B / FM2) SMR ratio with respect to February 2007 – R2 campaign GOME-2 FM3 Metop-A Do we have an Etalon correction problem? 31st August 2009 (before 2nd TT) 30th October 2009 (after 2nd TT) 31st July 2011 relative to February 2007

GOME-2 Metop-A Long-term throughput changes Solar Mean Reference (SMR) spectrum at 311 nm (FPA & PMD) GOME-2 FM3 Metop-A FPA-SMR smoothed (black line) with PMD spectral response function. R2 campaign Jan 2007 – Jan 2012 OPS phase (same PPF 5.3) Jan 2012 – Oct 2013

Goniometry: Angular dependence for Solar Measurements (AIRR) Comparison between current key-data and high res. elevation angle grid Band 3 solar signals at 420 nm GOME-2/Metop-A raw calibrated key-data Solar Elevation angle Solar Elevation angle Key-data – angle resolution In-flight derived values with increased angular resolution

Of relevance also for other current and future missions! Goniometry: Angular dependence for Solar Measurements (AIRR) Comparison between current key-data and high res. elevation angle grid GOME-2 FM3 Metop-A The Angular dependence of irradiance on the diffuser in elevation and solar azimuth I0(f,e) is difficult to measure on-ground (long-measurement period / in vacuum) but one can derive it from in-flight data 1 year of in-flight data needed FM3 on-ground key-data In-flight data Of relevance also for other current and future missions!

GOME-2 FM3 Metop-A Goniometry: Improved AIRR measurements for FM-2 TNO FM2 delta calibration campaign (Kenter et al.) GOME-2 FM2 Metop-B SAA: 0.5 resolution (317 to 333) Elevation: 0.1 resolution (-1.5 to 1.5) Similar to L1-processor angle fine-grid as defined in initialisation file! FM3 Metop A Original angular resolution FM2 Metop B Higher angular resolution

Goniometry: Angular dependence for Solar Measurements (AIRR) Comparison between current key-data and in-orbit derived data Angular domain – azimuth angle at 311 nm GOME-2 FM3 Metop-A FM3 on-ground key-data FM3 in-flight data In-flight data The Angular dependence of irradiance on the diffuser in elevation and solar azimuth I0(f,e) is difficult to measure on-ground (long-measurement period / in vacuum)... ...and can lead to artefacts in the long-term time-series of reflectances!

Goniometry: Angular dependence for Solar Measurements (AIRR) Application of in-orbit derived slit-function 260 and 330 nm GOME-2 FM3 Metop-A

Goniometry: Angular dependence for Solar Measurements (AIRR) Application of in-orbit derived slit-function 450 and 745 nm GOME-2 FM3 Metop-A

Goniometry: Angular dependence for Solar Measurements (AIRR) Application of in-orbit derived slit-function 745 nm GOME-2 FM3 Metop-A

Goniometry: Angular dependence for Solar Measurements (AIRR) Application of in-orbit derived slit-function PMD-S band 12 GOME-2 FM3 Metop-A

Goniometry: Angular dependence for Solar Measurements (AIRR) Application of in-orbit derived slit-function PMD-S band 8 GOME-2 FM3 Metop-A

Goniometry: Angular dependence for Solar Measurements (AIRR) Comparison between current key-data and in-orbit derived data Spectral domain – Channel 1 GOME-2 FM3 Metop-A FM3 in-flight data FM3 on-ground key-data The Angular dependence of irradiance on the diffuser in elevation and solar azimuth I0(f,e) is difficult to measure on-ground (long-measurement period / in vacuum)... ...and can lead to artefacts in the spectral domain of the solar mean reference measurements!

Goniometry: Angular dependence for Solar Measurements (AIRR) Application for SMR spectrum in Jan/Feb 2007 GOME-2 FM3 Metop-A New In-flight ARR Reference

Goniometry: Angular dependence for Solar Measurements (AIRR) Application for SMR spectrum in Jan/Feb 2007 GOME-2 FM3 Metop-A New In-flight ARR vs reference

GOME-2 Metop-A Long-term throughput changes Solar Mean Reference (SMR) spectrum GOME-2 FM3 Metop-A Reprocessed signals R2/NRT PPF 5.3 until October 2013 relative to February 2007

GOME-2 Metop-A Long-term throughput changes Solar Mean Reference (SMR) spectrum GOME-2 FM3 Metop-A Reprocessed signals R2/NRT PPF 5.3 until October 2013 relative to February 2007

GOME-2 Metop-A Long-term throughput changes Solar Mean Reference (SMR) spectrum GOME-2 FM3 Metop-A PMD-P PMD-S Reprocessed signals R2/NRT PPF 5.3 until October 2013 relative to February 2007

GOME-2 Metop-A Long-term throughput changes Solar Mean Reference (SMR) spectrum at 311 nm (FPA & PMD) GOME-2 FM3 Metop-A FPA-SMR smoothed (black line) with PMD spectral response function. R2 campaign Jan 2007 – Jan 2012 OPS phase (same PPF 5.3) Jan 2012 – Oct 2013

GOME-2 Metop-A Long-term throughput changes Solar Mean Reference (SMR) spectrum at 570 nm (FPA & PMD) GOME-2 FM3 Metop-A FPA-SMR smoothed (black line) with PMD spectral response function. R2 campaign Jan 2007 – Jan 2012 OPS phase (same PPF 5.3) Jan 2012 – Oct 2013

GOME-2 Metop-A Long-term throughput changes On-board calibration sources at 311 nm (FPA) GOME-2 FM3 Metop-A FPA-cal sources smoothed with PMD spectral response function where indicated. R2 campaign Jan 2007 – Jan 2012 OPS phase (same PPF 5.3) Jan 2012 – Oct 2013

GOME-2 Metop-A Long-term throughput changes On-board calibration sources at 570 nm (FPA) GOME-2 FM3 Metop-A FPA-cal sources smoothed with PMD spectral response function where indicated. R2 campaign Jan 2007 – Jan 2012 OPS phase (same PPF 5.3) Jan 2012 – Oct 2013

GOME-2 Metop-A Long-term throughput changes On-board calibration ETALON (FPA) GOME-2 FM3 Metop-A R2 campaign Jan 2007 – Jan 2012 OPS phase (same PPF 5.3) Jan 2012 – Oct 2013

GOME-2 Metop-A Long-term throughput changes On-board calibration ETALON (FPA) GOME-2 FM3 Metop-A R2 campaign Jan 2007 – Jan 2012 OPS phase (same PPF 5.3) Jan 2012 – Oct 2013

GOME-2 Metop-A Long-term throughput changes On-board calibration ETALON (PMDs) GOME-2 FM3 Metop-A PMD-P PMD-S R2 campaign Jan 2007 – Jan 2012 OPS phase (same PPF 5.3) Jan 2012 – Oct 2013

GOME-2 Metop-A Earthshine degradation until August 2011 Sahara – 311nm – relative to mean of 2007 GOME-2 FM3 Metop-A Earthshine Sahara Normalised to 2007 Every 2nd scanner angle position is used (coloured solid lines) Solar Mean Reference (black dashed line) Low outliers are due to interfering narrow scan R2 campaign Jan 2007 – Aug 2011

GOME-2 Metop-A Reflectivity degradation Sahara – at 312 nm – before and after 2nd throughput test GOME-2 FM3 Metop-A Earthshine Sahara Every scanner angle position is shown Rates in %/year R2 campaign Jan 2007– Jan 2012 Before Sep. 2009 After Sep. 2009

GOME-2 Metop-A degradation component modelling Sahara at 340 nm – temporal domain GOME-2 FM3 Metop-A R2 campaign Jan 2007– Jan 2012 320 nm Solar Reference Earthshine Reflectivity Model/Fit-Results

GOME-2 Metop-A degradation component modelling Sahara at 340 nm – temporal domain GOME-2 FM3 Metop-A R2 campaign Jan 2007– Jan 2012 570 nm Earthshine & Reflectivity over viewing angle

GOME-2 Metop-A degradation component modelling Sahara at 340 nm – temporal domain GOME-2 FM3 Metop-A R2 campaign Jan 2007– Jan 2012 325/340/380 nm Reflectivity degradation

GOME-2 Metop-A degradation component modelling Sahara at 340 nm – temporal domain GOME-2 FM3 Metop-A R2 campaign Jan 2007– Jan 2012 325/340/380 nm Reflectivity degradation Empirical degradation correction from AAI level-2, Tilstra et al., AAI Reprocessing ATBD, 2014.

GOME-2 Metop-A degradation component modelling Sahara at 340 nm – temporal domain GOME-2 FM3 Metop-A R2 campaign Jan 2007– Jan 2012 325 nm Reflectivity degradation

GOME-2 Metop-A degradation component modelling Sahara at 340 nm – temporal domain GOME-2 FM3 Metop-A R2 campaign Jan 2007– Jan 2012 340 nm Reflectivity degradation

GOME-2 Metop-A degradation component modelling Sahara at 340 nm – temporal domain GOME-2 FM3 Metop-A R2 campaign Jan 2007– Jan 2012 380 nm Reflectivity degradation

GOME-2 Metop-A degradation component modelling Sahara at 340 nm – temporal domain GOME-2 FM3 Metop-A R2 campaign Jan 2007– Jan 2012 380 nm Reflectivity degradation Empirical degradation correction from AAI level-2, Tilstra et al., AAI Reprocessing ATBD, 2014.

GOME-2 Metop-A degradation component modelling Sahara – spectral domain at various periods in time GOME-2 FM3 Metop-A R2 campaign Jan 2007– Jan 2012 2007 2008 2009 2011 Spectra from modelled trend results Spectrally smoothed model trend results

GOME-2 Metop-A degradation component modelling Sahara – spectral domain at various periods in time GOME-2 FM3 Metop-A R2 campaign Jan 2007– Jan 2012 2007 2008 2009 2011 Spectra from modelled trend results Spectrally smoothed model trend results

GOME-2 Metop-A degradation component modelling Sahara – spectral domain at various periods in time GOME-2 FM3 Metop-A R2 campaign Jan 2007– Jan 2012 2007 2008 2009 2011 Spectra from modelled trend results Spectrally smoothed model trend results

GOME-2 Metop-A degradation component modelling Sahara – spectral domain at various periods in time GOME-2 FM3 Metop-A R2 campaign Jan 2007– Jan 2012 2007 2008 2009 2011 Spectra from modelled trend results Spectrally smoothed model trend results

GOME scan mirror contribution Adapted SRON GOME-1 model results for GOME-2 GOME ERS-2 Scan mirror degradation Adapted to GOME-2 from GOME-1 in spectral and temporal space Model data provided by Snel and Krijger, SRON

GOME-2 scan mirror contribution vs instrument degradation SMR and scan mirror contribution GOME-2 FM3 Metop-A Scan mirror and instrument degradation Scan mirror model data based on GOME-1 provided by Snel and Krijger, SRON

GOME-2 instrument degradation Hypothesis by the ESA/EUMETSAT/Industry GOME-2 tiger team Arathene out-gassing by conformal coatings. Hyposesis posed by the “ESA/EUMETSAT/Industry GOME-2 tiger team on instrument degradation.” Arathene absorption spectra “Peak at 310 nm corresponds to a more volatile component in the Arathene, which is effectively removed from the conformal coating by the bake-out process which is applied in the “real instrument PCBs” Scan mirror model data based on GOME-1 provided by Snel and Krijger, SRON

GOME-2 Metop-A degradation component modelling Sahara – spectral domain at various periods in time GOME-2 FM3 Metop-A R2 campaign Jan 2007– Jan 2012 2007 2008 2009 2011 Spectra from modelled trend results Spectrally smoothed model trend results

GOME-2 Metop-A degradation component modelling Sahara – spectral domain at various periods in time GOME-2 FM3 Metop-A R2 campaign Jan 2007– Jan 2012 Diffuser+Mirror Arathene+Mirror

GOME-2 Metop-A degradation component modelling Sahara – spectral domain at various periods in time GOME-2 FM3 Metop-A

GOME-2 Metop-A degradation component modelling Sahara – spectral domain at various periods in time GOME-2 FM3 Metop-A

GOME-2 Metop-A degradation component modelling Sahara – spectral domain at various periods in time GOME-2 FM3 Metop-A

Modelled Earthshine degradation Modelled Solar Path degradation GOME-2 Metop-A degradation component modelling Sahara – spectral and temporal domain GOME-2 FM3 Metop-A Modelled Earthshine degradation Modelled Solar Path degradation 800 nm 240 nm Feb 2007 June 2013 Feb 2007 June 2013 R2 campaign Jan 2007– June 2013

GOME-2 Metop-A degradation component modelling Sahara reflectivity – spectral and temporal domain GOME-2 FM3 Metop-A R2 campaign Jan 2007– June 2013 800 nm Earthshine Trend 240 nm Feb 2007 June 2013

GOME-2 Metop-A degradation component modelling Sahara reflectivity – spectral and temporal domain GOME-2 FM3 Metop-A R2 campaign Jan 2007– June 2013 800 nm Reflectivity Trend 240 nm Feb 2007 June 2013

GOME-2 Metop-A degradation component modelling Sahara reflectivity – spectral and temporal domain GOME-2 FM3 Metop-A R2 campaign Jan 2007– June 2013 800 nm Reflectivity Trend 240 nm Feb 2007 June 2013

GOME-2 Metop-A degradation component modelling Impact on level-2 using degradation correction GOME-2 FM3 Metop-A R2 campaign Jan 2007– June 2013 Reflectivity Trend

Instrument degradation Comparison Metop-B/A - first months in orbit GOME-2 FM3 Metop-A Instrument degradation Comparison Metop-B/A - first months in orbit GOME-2 FM2 Metop-B Degradation over four month in-orbit covering the same in-orbit lifetime! 122 Days! Metop-A Metop-B FM2 (Metop-B) degrades roughly in the same way as FM3 (Metop-A) except for channel 2. ...reason yet unkown!

Instrument degradation Comparison Metop-B/A - first year in orbit GOME-2 FM3 Metop-A Instrument degradation Comparison Metop-B/A - first year in orbit GOME-2 FM2 Metop-B Degradation after one year in-orbit covering the same in-orbit lifetime! 365 Days! Metop-A Metop-B FM2 (Metop-B) degrades roughly in the same way as FM3 (Metop-A) except for channel 2. ...reason yet unkown!

Instrument degradation Comparison Metop-B/A – first 1.5 years in orbit GOME-2 FM3 Metop-A Instrument degradation Comparison Metop-B/A – first 1.5 years in orbit GOME-2 FM2 Metop-B Degradation after 1.5 years in-orbit covering the same in-orbit lifetime! 547 Days! Metop-A Metop-B FM2 (Metop-B) degrades roughly in the same way as FM3 (Metop-A) except for channel 2. ...reason yet unkown!

Instrument degradation Comparison Metop-B/A - first months in orbit GOME-2 FM3 Metop-A Instrument degradation Comparison Metop-B/A - first months in orbit GOME-2 FM2 Metop-B PMD-P PMD-S Metop-A Metop-B 122 Days! Degradation over four month in-orbit covering the same in-orbit lifetime!

Instrument degradation Comparison Metop-B/A - first year in orbit GOME-2 FM3 Metop-A Instrument degradation Comparison Metop-B/A - first year in orbit GOME-2 FM2 Metop-B PMD-P PMD-S Metop-A Metop-B 365 Days! Degradation over 1 year in-orbit covering the same in-orbit lifetime!

Instrument degradation Comparison Metop-B/A - first 1.5 years in orbit GOME-2 FM3 Metop-A Instrument degradation Comparison Metop-B/A - first 1.5 years in orbit GOME-2 FM2 Metop-B PMD-P PMD-S Metop-A Metop-B 547 Days! Degradation over 1.5 years in-orbit covering the same in-orbit lifetime!

GOME-2 Metop-A/B Long-term throughput changes GOME-2 FM3 Metop-A GOME-2 Metop-A/B Long-term throughput changes On-board calibration sources at 311 nm (FPA) GOME-2 FM2 Metop-B FPA-cal sources smoothed with PMD spectral response function where indicated. Metop-A R2 campaign Jan 2007 – Oct 2007 Metop-B OPS Jan 2013 – Oct 2013

GOME-2 Metop-A/B Long-term throughput changes GOME-2 FM3 Metop-A GOME-2 Metop-A/B Long-term throughput changes On-board calibration sources at 311 nm (FPA) GOME-2 FM2 Metop-B FPA-cal sources smoothed with PMD spectral response function where indicated. Metop-A R2 campaign Jan 2007 – Oct 2007 Metop-B OPS Jan 2013 – Oct 2013

GOME-2 Metop-B Long-term throughput changes On-board calibration sources at 745 nm (FPA) GOME-2 FM2 Metop-B Solar mean reference Metop-B OPS December 2012- July 2014

Earthshine Trend/Forecast GOME-2 degradation component modelling Signal level prediction – Based on GOME-2 Metop-A Degradation model v0.9 GOME-2 FM3 Metop-A Earthshine Trend/Forecast Solar Trend/Forecast

GOME-2 degradation component modelling Signal level prediction GOME-2 FM3 Metop-A Reflectivity Trend/Forecast

Earthshine Trend/Forecast GOME-2/Metop-B degradation component modelling Signal level prediction – Based on GOME-2 Metop-A Degradation model v0.9 GOME-2 FM2 Metop-B Earthshine Trend/Forecast Solar Trend/Forecast

GOME-2/Metop-B degradation component modelling Signal level prediction GOME-2 FM2 Metop-B Reflectivity Trend/Forecast

Earthshine Trend/Forecast GOME-2/Metop-C degradation component modelling Signal level prediction – Based on GOME-2 Metop-A Degradation model v0.9 GOME-2 FM1 Metop-C Earthshine Trend/Forecast Solar Trend/Forecast

GOME-2/Metop-C degradation component modelling Signal level prediction GOME-2 FM1 Metop-C Reflectivity Trend/Forecast

GOME-2 Metop-A diffuser stability Normalised signal of spectral line source (SLS) over diffuser - monthly GOME-2 FM3 Metop-A Diffuser signal trend Slight increase i.e. Slight diffuser degradation detected! <10% in 7 Years R2 campaign Jan 2007 – Jan 2012 OPS phase (same PPF 5.3) Jan 2012 – Oct 2013

GOME-2 / Metop-A End of Life scenario Loss of solar measurments GOME-2 FM3 Metop-A

GOME-2 / Metop-A End of Life scenario Loss of solar measurements GOME-2 FM3 Metop-A

GOME-2 / Metop-A End of Life scenario Loss of solar measurements GOME-2 FM3 Metop-A Double OOP in Autumn 2015 Gap1 (beginning 2017) Days Gap2 (end 2017/ beginning 2018) Gap3 (end 2018/ continuing in 2019) Total Number of Days with no GOME Sun Visibility Burn Start at Eclipse Entry 2017/01/23- 2017/02/22 31 2017/12/29-2018/03/17 79 2018/11/13- 2019/01/01 (2019/05/02) 49 (171) 159 (281) Burn Start at Eclipse Entry FOV + 0.5deg 2017/02/11-2017/02/03 8 2018/01/02- 2018/03/15 73 2018/11/21- (2019/04/24) 41 (155) 122 (234) Burn Start at Eclipse Entry -60s 2017/01/27- 2017/02/17 22 2018/01/01- 74 2018/11/23- (2019/04/23) 39 (152) 135 (248) Burn Start at Eclipse Entry -60s + 0.5deg(*) 67 20 (143) 87 (210) Burn Start at Eclipse Entry -120s 2017/02/03-2017/02/10 2018/01/04-2018/03/12 68 2018/11/30- (2019/04/16) 32 (138) 108 (214) Burn Start at Eclipse Entry -120s + 0.5deg(*) 60 10 (132) 70 (192)

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