18098( 5) - 26-Feb-2026 23:13:07 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 18098 Version: 5 Check-in Time: 26-Feb-2026 23:13:07 STScI Edit Number: 1 Title Is Sulfur stored in the refractory or volatile component of planetary building blocks? ------------------------------------------------------------------------------------ Type Cycle GO 33 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Amy Bonsor University of Cambridge Y CoI: Dr. Laura Rogers NOIRLab - (AZ) N CoI: Dr. Siyi Xu NOIRLab - Gemini North (HI) N CoI: Dr. Patrick Dufour Universite de Montreal N CoI: Dr. Simon Blouin University of Victoria N CoI: Mihkel Kama University College London N CoI: Dr. Oliver Shorttle University of Cambridge N CoI: Tyler Robinson University of Arizona N CoI: Dr. Sukrit Ranjan University of Arizona N ------------------------------------------------------------------------------------ Abstract Sulfur plays a key role in geochemical cycling on the Solar System's terrestrial planets and is required by all life. It can also form important spectrally active species in exoplanet atmospheres, affecting their climates and habitability. Yet, how abundant sulfur will be in exoplanets depends critically on how it is delivered to rocky planets during their formation, a journey that remains uncertain. Most notably it is not clear whether Sulfur is stored in the refractory (dust) phase of planetary building blocks or rather the volatile (ice) phase, the latter being much more readily lost to planets forming in the warm inner disk. This proposal will determine the Sulfur abundances in the planetary material in the atmospheres of 12 white dwarfs. Alongside oxygen, the abundances will tell us whether Sulfur is in ice or dust, providing a sufficiently large sample to answer the null hypothesis that Sulfur is predominantly found in the ice phase. ------------------------------------------------------------------------------------ Observations Description ------------------------ This program aims to measure the Sulfur abundance in a sample of polluted white dwarfs. All targets are brighter than 16.7 mag in GALEX NUV. Our primary setup is the G185M grating with a central wavelength of 1921A, which covers key sulfur lines SI 1807.3A and 1820.3A. For 4 targets (specially those with Helium-rich atmospheres) the S I 1253.8A is the strongest sulfur line, and therefore the G130M grating with a central wavelength of 1291A is used instead. Reduced gyro observations: Our observations are not time critical, and can be scheduled any time, so reducing the possible observing windows will not affect this proposal. Using the visit planner tool, there are plenty of schedulable opportunities across the cycle for all targets. Target acquisition is required for all of our targets in order to sucessfully complete the proposed observations. 18098( 5) - 26-Feb-2026 23:13:07 - [ 2] Scheduling: For targets which require >3 orbits, we have split the visits up to ensure maximum schedulability. ------------------------------------------------------------------------------------ 18098( 5) - 26-Feb-2026 23:13:07 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 WD2105-820 STAR, DA, DZ RA=21H13M16.8549S +/- 0.0137", J2000 V = 13.59 NUV=14.4 DEC=-81D49'12.88" +/- 0.0141" Reference Frame: ICRS Extended: NO Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. SIMBAD listed proper motion for this target. When retrieving targets with PM from SIMBAD, APT requests the coordinates be calculated with an epoch of the year 2000. Do not modify this epoch. Always review coordinates using the Target Confirmation tool, which graphically displays the PM. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2000 0.1237655683304344 -0.3799770000341596 0.0618087 ------------------------------------------------------------------------------------------------------------------------------------ 2 G29-38 STAR, DA, DZ RA=23H28M47.6365S +/- 0.0217", J2000 V = 13.04 NUV=13.85 DEC=+05D14'54.24" +/- 0.0173" Reference Frame: ICRS Extended: NO Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. SIMBAD listed proper motion for this target. When retrieving targets with PM from SIMBAD, APT requests the coordinates be calculated with an epoch of the year 2000. Do not modify this epoch. Always review coordinates using the Target Confirmation tool, which graphically displays the PM. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2000 -0.026661512192613757 -0.2667439999186172 0.057061999999999995 ------------------------------------------------------------------------------------------------------------------------------------ 3 GD133 STAR, DA, DZ RA=11H19M12.3989S +/- 0.0298", J2000 V = 14.57 NUV=15.08 DEC=+02D20'33.05" +/- 0.0222" Reference Frame: ICRS Extended: NO Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. SIMBAD listed proper motion for this target. When retrieving targets with PM from SIMBAD, APT requests the coordinates be calculated with an epoch of the year 2000. Do not modify this epoch. Always review coordinates using the Target Confirmation tool, which graphically displays the PM. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2000 -0.006694527669157644 0.030978 0.026150800000000002 ------------------------------------------------------------------------------------------------------------------------------------ 18098( 5) - 26-Feb-2026 23:13:07 - [ 4] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 4 EC-23379-372 STAR, DA, DZ RA=23H40M36.6398S +/- 0.0465", J2000 V = 16.17 NUV=16.23 5 DEC=-37D08'44.72" +/- 0.0366" Reference Frame: ICRS Extended: NO Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. SIMBAD listed proper motion for this target. When retrieving targets with PM from SIMBAD, APT requests the coordinates be calculated with an epoch of the year 2000. Do not modify this epoch. Always review coordinates using the Target Confirmation tool, which graphically displays the PM. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2000 -0.0029402344736871966 -0.024749999988671334 0.010509600000000001 ------------------------------------------------------------------------------------------------------------------------------------ 5 WD1133-528 STAR, DA, DZ RA=11H35M57.3425S +/- 0.0247", J2000 V = 15.8 NUV=15.99 DEC=-53D03'22.12" +/- 0.0236" Reference Frame: ICRS Extended: NO Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. SIMBAD listed proper motion for this target. When retrieving targets with PM from SIMBAD, APT requests the coordinates be calculated with an epoch of the year 2000. Do not modify this epoch. Always review coordinates using the Target Confirmation tool, which graphically displays the PM. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2000 -0.022713926478410428 0.12849100000000002 0.0114977 ------------------------------------------------------------------------------------------------------------------------------------ 6 GD-56 STAR, DA, DZ RA=04H11M2.1687S +/- 0.0333", J2000 V = 15.5 NUV=15.59 DEC=-03D58'22.59" +/- 0.0331" Reference Frame: ICRS Extended: NO Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. SIMBAD listed proper motion for this target. When retrieving targets with PM from SIMBAD, APT requests the coordinates be calculated with an epoch of the year 2000. Do not modify this epoch. Always review coordinates using the Target Confirmation tool, which graphically displays the PM. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2000 2.4592431848963626E-4 -0.12854999993123783 0.013973000000000001 ------------------------------------------------------------------------------------------------------------------------------------ 18098( 5) - 26-Feb-2026 23:13:07 - [ 5] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 7 WD0106-328 STAR, DA, DZ RA=01H08M36.0346S +/- 0.0291", J2000 V = 15.26 NUV=15.28 DEC=-32D37'43.38" +/- 0.0182" Reference Frame: ICRS Extended: NO Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. SIMBAD listed proper motion for this target. When retrieving targets with PM from SIMBAD, APT requests the coordinates be calculated with an epoch of the year 2000. Do not modify this epoch. Always review coordinates using the Target Confirmation tool, which graphically displays the PM. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2000 0.0021025535912669903 -0.021663999950760626 0.014513199999999999 ------------------------------------------------------------------------------------------------------------------------------------ 8 WD1226+110 STAR, DA, DZ RA=12H28M59.9342S +/- 0.0529", J2000 V = 16.46 NUV=15.75 DEC=+10D40'33.05" +/- 0.0420" Reference Frame: ICRS Extended: NO Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. SIMBAD listed proper motion for this target. When retrieving targets with PM from SIMBAD, APT requests the coordinates be calculated with an epoch of the year 2000. Do not modify this epoch. Always review coordinates using the Target Confirmation tool, which graphically displays the PM. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2000 -0.00340927793979949 -0.02472900000611844 0.0077634 ------------------------------------------------------------------------------------------------------------------------------------ 9 WD1244+498 STAR, DB, DZ RA=12H47M3.2755S +/- 0.0330", J2000 V = 16.59 NUV=16.49 DEC=+49D34'23.52" +/- 0.0394" Reference Frame: ICRS Extended: NO Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. SIMBAD listed proper motion for this target. When retrieving targets with PM from SIMBAD, APT requests the coordinates be calculated with an epoch of the year 2000. Do not modify this epoch. Always review coordinates using the Target Confirmation tool, which graphically displays the PM. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2000 0.001158819481712987 0.042186999999999995 0.008308099999999999 ------------------------------------------------------------------------------------------------------------------------------------ 18098( 5) - 26-Feb-2026 23:13:07 - [ 6] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 10 SDSSJ173435. STAR, DB, DZ RA=17H34M35.7473S +/- 0.0464", J2000 V = 16.98 NUV=16.69 7+605203 DEC=+60D52'3.22" +/- 0.0559" Reference Frame: ICRS Extended: NO Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. SIMBAD listed proper motion for this target. When retrieving targets with PM from SIMBAD, APT requests the coordinates be calculated with an epoch of the year 2000. Do not modify this epoch. Always review coordinates using the Target Confirmation tool, which graphically displays the PM. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2000 -0.004135187488013198 -0.005580999982157664 0.0066565 ------------------------------------------------------------------------------------------------------------------------------------ 11 WD1415+234 STAR, DB, DZ RA=14H17M55.3674S +/- 0.0406", J2000 V = 16.8 NUV=16.46 DEC=+23D11'36.71" +/- 0.0420" Reference Frame: ICRS Extended: NO Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. SIMBAD listed proper motion for this target. When retrieving targets with PM from SIMBAD, APT requests the coordinates be calculated with an epoch of the year 2000. Do not modify this epoch. Always review coordinates using the Target Confirmation tool, which graphically displays the PM. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2000 -0.00437012787870942 0.037469999999999996 0.0078811 ------------------------------------------------------------------------------------------------------------------------------------ 12 PG-1015+161 STAR, DB, DZ RA=10H18M3.8273S +/- 0.0409", J2000 V = 15.61 NUV=15.21 DEC=+15D51'58.57" +/- 0.0364" Reference Frame: ICRS Extended: NO Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. SIMBAD listed proper motion for this target. When retrieving targets with PM from SIMBAD, APT requests the coordinates be calculated with an epoch of the year 2000. Do not modify this epoch. Always review coordinates using the Target Confirmation tool, which graphically displays the PM. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2000 -0.007704385052432629 -0.06867899994631443 0.0113617 ------------------------------------------------------------------------------------------------------------------------------------ 18098( 5) - 26-Feb-2026 23:13:07 - [ 7] Visit: 01 (WD2105-820) Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 WD2105-820 COS/NUV ACQ/IMA PSA MIRRORB 1 5 S (5 S) GE ------------------------------------------------------------------------------------------------------------------------------------ 2 WD2105-820 COS/NUV TIME-TA PSA G185M 1921 BUFFER-TIME=1119, FP-POS=ALL 1 1250 S G see below (4995 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ WD2105-820 1 COS/NUV ACQ/IMA PSA MIRRORB none none none none 1 N/A GE WD2105-820 2 COS/NUV TIME-TA PSA G185M 1921 none none none 1 1 1150.0 S G WD2105-820 2 COS/NUV TIME-TA PSA G185M 1921 none none none 2 1 1149.0 S G WD2105-820 2 COS/NUV TIME-TA PSA G185M 1921 none none none 3 2 1348.0 S G WD2105-820 2 COS/NUV TIME-TA PSA G185M 1921 none none none 4 2 1348.0 S G 18098( 5) - 26-Feb-2026 23:13:07 - [ 8] Visit: 02 (G29-38) Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 G29-38 COS/NUV ACQ/IMA BOA MIRRORA 1 15 S (15 GE S) ------------------------------------------------------------------------------------------------------------------------------------ 2 G29-38 COS/NUV TIME-TA PSA G185M 1921 BUFFER-TIME=1019, FP-POS=ALL 1 477 S G (1908 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ G29-38 1 COS/NUV ACQ/IMA BOA MIRRORA none none none none 1 N/A GE G29-38 2 COS/NUV TIME-TA PSA G185M 1921 none none none 1 1 N/A G G29-38 2 COS/NUV TIME-TA PSA G185M 1921 none none none 2 1 N/A G G29-38 2 COS/NUV TIME-TA PSA G185M 1921 none none none 3 1 N/A G G29-38 2 COS/NUV TIME-TA PSA G185M 1921 none none none 4 1 N/A G 18098( 5) - 26-Feb-2026 23:13:07 - [ 9] Visit: 03 (GD133) Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 GD133 COS/NUV ACQ/IMA PSA MIRRORB 1 9 S (9 S) GE ------------------------------------------------------------------------------------------------------------------------------------ 2 GD133 COS/NUV TIME-TA PSA G185M 1921 BUFFER-TIME=1171, FP-POS=ALL 1 1062 S G see below (4517 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ GD133 1 COS/NUV ACQ/IMA PSA MIRRORB none none none none 1 N/A GE GD133 2 COS/NUV TIME-TA PSA G185M 1921 none none none 1 1 1050.0 S G GD133 2 COS/NUV TIME-TA PSA G185M 1921 none none none 2 1 1049.0 S G GD133 2 COS/NUV TIME-TA PSA G185M 1921 none none none 3 2 1209.0 S G GD133 2 COS/NUV TIME-TA PSA G185M 1921 none none none 4 2 1209.0 S G 18098( 5) - 26-Feb-2026 23:13:07 - [ 10] Visit: 04 (EC-23379-3725-VISIT-1) Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 EC-23379-37 COS/NUV ACQ/IMA PSA MIRRORB 1 25 S (25 25 GE S) ------------------------------------------------------------------------------------------------------------------------------------ 2 EC-23379-37 COS/NUV TIME-TA PSA G185M 1921 BUFFER-TIME=1228, FP-POS=ALL 1 1068 S 25 G see below (4530 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ EC-23379-3725 1 COS/NUV ACQ/IMA PSA MIRRORB none none none none 1 N/A GE EC-23379-3725 2 COS/NUV TIME-TA PSA G185M 1921 none none none 1 1 1045.0 S G EC-23379-3725 2 COS/NUV TIME-TA PSA G185M 1921 none none none 2 1 1044.0 S G EC-23379-3725 2 COS/NUV TIME-TA PSA G185M 1921 none none none 3 2 1221.0 S G EC-23379-3725 2 COS/NUV TIME-TA PSA G185M 1921 none none none 4 2 1220.0 S G 18098( 5) - 26-Feb-2026 23:13:07 - [ 11] Visit: 05 (EC-23379-3725-VISIT-2) Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 EC-23379-37 COS/NUV ACQ/IMA PSA MIRRORB 1 25 S (25 25 GE S) ------------------------------------------------------------------------------------------------------------------------------------ 2 EC-23379-37 COS/NUV TIME-TA PSA G185M 1921 BUFFER-TIME=1228, FP-POS=ALL 1 1068 S 25 G see below (4530 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ EC-23379-3725 1 COS/NUV ACQ/IMA PSA MIRRORB none none none none 1 N/A GE EC-23379-3725 2 COS/NUV TIME-TA PSA G185M 1921 none none none 1 1 1045 S G EC-23379-3725 2 COS/NUV TIME-TA PSA G185M 1921 none none none 2 1 1044 S G EC-23379-3725 2 COS/NUV TIME-TA PSA G185M 1921 none none none 3 2 1221 S G EC-23379-3725 2 COS/NUV TIME-TA PSA G185M 1921 none none none 4 2 1220.0 S G 18098( 5) - 26-Feb-2026 23:13:07 - [ 12] Visit: 06 (WD1133-528) Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 WD1133-528 COS/NUV ACQ/IMA PSA MIRRORB 1 20 S (20 GE S) ------------------------------------------------------------------------------------------------------------------------------------ 2 WD1133-528 COS/NUV TIME-TA PSA G185M 1921 BUFFER-TIME=1218, FP-POS=ALL 1 2319 S G see below (7352 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ WD1133-528 1 COS/NUV ACQ/IMA PSA MIRRORB none none none none 1 N/A GE WD1133-528 2 COS/NUV TIME-TA PSA G185M 1921 none none none 1 1 2268.0 S G WD1133-528 2 COS/NUV TIME-TA PSA G185M 1921 none none none 2 2 1233.0 S G WD1133-528 2 COS/NUV TIME-TA PSA G185M 1921 none none none 3 2 1232.0 S G WD1133-528 2 COS/NUV TIME-TA PSA G185M 1921 none none none 4 3 2619.0 S G 18098( 5) - 26-Feb-2026 23:13:07 - [ 13] Visit: 07 (GD56) Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 GD-56 COS/NUV ACQ/IMA PSA MIRRORB 1 13 S (13 GE S) ------------------------------------------------------------------------------------------------------------------------------------ 2 GD-56 COS/NUV TIME-TA PSA G185M 1921 BUFFER-TIME=1195, FP-POS=ALL 1 1062 S G see below (4518 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ GD-56 1 COS/NUV ACQ/IMA PSA MIRRORB none none none none 1 N/A GE GD-56 2 COS/NUV TIME-TA PSA G185M 1921 none none none 1 1 1050.0 S G GD-56 2 COS/NUV TIME-TA PSA G185M 1921 none none none 2 1 1050.0 S G GD-56 2 COS/NUV TIME-TA PSA G185M 1921 none none none 3 2 1209.0 S G GD-56 2 COS/NUV TIME-TA PSA G185M 1921 none none none 4 2 1209.0 S G 18098( 5) - 26-Feb-2026 23:13:07 - [ 14] Visit: 08 (WD0106-328) Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 WD0106-328 COS/NUV ACQ/IMA PSA MIRRORB 1 10 S (10 GE S) ------------------------------------------------------------------------------------------------------------------------------------ 2 WD0106-328 COS/NUV TIME-TA PSA G185M 1921 BUFFER-TIME=1164, FP-POS=ALL 1 1076 S G see below (4531 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ WD0106-328 1 COS/NUV ACQ/IMA PSA MIRRORB none none none none 1 N/A GE WD0106-328 2 COS/NUV TIME-TA PSA G185M 1921 none none none 1 1 1053.0 S G WD0106-328 2 COS/NUV TIME-TA PSA G185M 1921 none none none 2 1 1052.0 S G WD0106-328 2 COS/NUV TIME-TA PSA G185M 1921 none none none 3 2 1213.0 S G WD0106-328 2 COS/NUV TIME-TA PSA G185M 1921 none none none 4 2 1213 S G 18098( 5) - 26-Feb-2026 23:13:07 - [ 15] Visit: 09 (WD1226+110) Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 WD1226+110 COS/NUV ACQ/IMA PSA MIRRORB 1 15 S (15 GE S) ------------------------------------------------------------------------------------------------------------------------------------ 2 WD1226+110 COS/NUV TIME-TA PSA G185M 1921 BUFFER-TIME=1192, FP-POS=ALL 1 1061 S G see below (4504 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ WD1226+110 1 COS/NUV ACQ/IMA PSA MIRRORB none none none none 1 N/A GE WD1226+110 2 COS/NUV TIME-TA PSA G185M 1921 none none none 1 1 1046.0 S G WD1226+110 2 COS/NUV TIME-TA PSA G185M 1921 none none none 2 1 1045.0 S G WD1226+110 2 COS/NUV TIME-TA PSA G185M 1921 none none none 3 2 1207.0 S G WD1226+110 2 COS/NUV TIME-TA PSA G185M 1921 none none none 4 2 1206.0 S G 18098( 5) - 26-Feb-2026 23:13:07 - [ 16] Visit: 10 (WD1244+498 - VISIT 1) Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 WD1244+498 COS/NUV ACQ/IMA PSA MIRRORB 1 31 S (31 GE S) ------------------------------------------------------------------------------------------------------------------------------------ 2 WD1244+498 COS/FUV TIME-TA PSA G130M 1291 BUFFER-TIME=3486, FP-POS=3 1 2139 S G (2139 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 WD1244+498 COS/FUV TIME-TA PSA G130M 1291 BUFFER-TIME=3486, FP-POS=4 1 2571 S G (2571 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ WD1244+498 1 COS/NUV ACQ/IMA PSA MIRRORB none none none none 1 N/A GE WD1244+498 2 COS/FUV TIME-TA PSA G130M 1291 none none none none 1 N/A G WD1244+498 3 COS/FUV TIME-TA PSA G130M 1291 none none none none 2 N/A G 18098( 5) - 26-Feb-2026 23:13:07 - [ 17] Visit: 11 (WD1244+498 - VISIT 2) Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 WD1244+498 COS/NUV ACQ/IMA PSA MIRRORB 1 31 S (31 GE S) ------------------------------------------------------------------------------------------------------------------------------------ 2 WD1244+498 COS/FUV TIME-TA PSA G130M 1291 BUFFER-TIME=3486, FP-POS=3 1 2139 S G (2139 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 WD1244+498 COS/FUV TIME-TA PSA G130M 1291 BUFFER-TIME=3486, FP-POS=4 1 2571 S G (2571 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ WD1244+498 1 COS/NUV ACQ/IMA PSA MIRRORB none none none none 1 N/A GE WD1244+498 2 COS/FUV TIME-TA PSA G130M 1291 none none none none 1 N/A G WD1244+498 3 COS/FUV TIME-TA PSA G130M 1291 none none none none 2 N/A G 18098( 5) - 26-Feb-2026 23:13:07 - [ 18] Visit: 12 (SDSSJ173435.7+605203 - VISIT 1) Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 SDSSJ173435 COS/NUV ACQ/IMA PSA MIRRORB 1 55 S (55 .7+605203 GE S) ------------------------------------------------------------------------------------------------------------------------------------ 2 SDSSJ173435 COS/FUV TIME-TA PSA G130M 1291 BUFFER-TIME=3521, FP-POS=3 1 2144 S .7+605203 G (2144 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 SDSSJ173435 COS/FUV TIME-TA PSA G130M 1291 BUFFER-TIME=3521, FP-POS=4 1 2624 S .7+605203 G (2624 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ SDSSJ173435.7+60520 1 COS/NUV ACQ/IMA PSA MIRRORB none none none none 1 N/A 3 GE SDSSJ173435.7+60520 2 COS/FUV TIME-TA PSA G130M 1291 none none none none 1 N/A 3 G SDSSJ173435.7+60520 3 COS/FUV TIME-TA PSA G130M 1291 none none none none 2 N/A 3 G 18098( 5) - 26-Feb-2026 23:13:07 - [ 19] Visit: 13 (SDSSJ173435.7+605203 - VISIT 2) Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 SDSSJ173435 COS/NUV ACQ/IMA PSA MIRRORB 1 55 S (55 .7+605203 GE S) ------------------------------------------------------------------------------------------------------------------------------------ 2 SDSSJ173435 COS/FUV TIME-TA PSA G130M 1291 BUFFER-TIME=3521, FP-POS=3 1 2144 S .7+605203 G (2144 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 SDSSJ173435 COS/FUV TIME-TA PSA G130M 1291 BUFFER-TIME=3521, FP-POS=4 1 2624 S .7+605203 G (2624 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ SDSSJ173435.7+60520 1 COS/NUV ACQ/IMA PSA MIRRORB none none none none 1 N/A 3 GE SDSSJ173435.7+60520 2 COS/FUV TIME-TA PSA G130M 1291 none none none none 1 N/A 3 G SDSSJ173435.7+60520 3 COS/FUV TIME-TA PSA G130M 1291 none none none none 2 N/A 3 G 18098( 5) - 26-Feb-2026 23:13:07 - [ 20] Visit: 14 (WD 1415+234) Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 WD1415+234 COS/NUV ACQ/IMA PSA MIRRORB 1 29 S (29 GE S) ------------------------------------------------------------------------------------------------------------------------------------ 2 WD1415+234 COS/NUV TIME-TA PSA G185M 1921 BUFFER-TIME=3118, FP-POS=3 1 2203 S G (2203 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 WD1415+234 COS/NUV TIME-TA PSA G185M 1921 BUFFER-TIME=3118, FP-POS=3 1 1238 S G (1238 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 WD1415+234 COS/NUV TIME-TA PSA G185M 1921 BUFFER-TIME=3118, FP-POS=4 1 1237 S G (1237 S) ------------------------------------------------------------------------------------------------------------------------------------ 5 WD1415+234 COS/NUV TIME-TA PSA G185M 1921 BUFFER-TIME=3118, FP-POS=4 1 2572 S G (2572 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ WD1415+234 1 COS/NUV ACQ/IMA PSA MIRRORB none none none none 1 N/A GE WD1415+234 2 COS/NUV TIME-TA PSA G185M 1921 none none none none 1 N/A G WD1415+234 3 COS/NUV TIME-TA PSA G185M 1921 none none none none 2 N/A G WD1415+234 4 COS/NUV TIME-TA PSA G185M 1921 none none none none 2 N/A G WD1415+234 5 COS/NUV TIME-TA PSA G185M 1921 none none none none 3 N/A G 18098( 5) - 26-Feb-2026 23:13:07 - [ 21] Visit: 15 (PG-1015+161) Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 PG-1015+161 COS/NUV ACQ/IMA PSA MIRRORB 1 9 S (9 S) GE ------------------------------------------------------------------------------------------------------------------------------------ 2 PG-1015+161 COS/FUV TIME-TA PSA G130M 1291 BUFFER-TIME=1159, FP-POS=3 1 1550 S G (1550 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 PG-1015+161 COS/FUV TIME-TA PSA G130M 1291 BUFFER-TIME=1159, FP-POS=4 1 1550 S G (1550 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ PG-1015+161 1 COS/NUV ACQ/IMA PSA MIRRORB none none none none 1 N/A GE PG-1015+161 2 COS/FUV TIME-TA PSA G130M 1291 none none none none 1 N/A G PG-1015+161 3 COS/FUV TIME-TA PSA G130M 1291 none none none none 2 N/A G 18098( 5) - 26-Feb-2026 23:13:07 - [ 22] Summary Form for Proposal 18098 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures BOA, PSA ------------------------------------------------------------------------------------------------------------------------------------ Configurations COS/FUV, COS/NUV ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ/IMAGE, TIME-TAG ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters BUFFER-TIME=1019, BUFFER-TIME=1119, BUFFER-TIME=1159, BUFFER-TIME=1164, BUFFER-TIME=1171, BUFFER-TIME=1192, BUFFER-TIME=1195, BUFFER-TIME=1218, BUFFER-TIME=1228, BUFFER-TIME=3118, BUFFER-TIME=3486, BUFFER-TIME=3521, FP-POS=3, FP-POS=4, FP-POS=ALL ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements G130M, G185M, MIRRORA, MIRRORB ------------------------------------------------------------------------------------------------------------------------------------ Target Names EC-23379-3725, G29-38, GD-56, GD133, PG-1015+161, SDSSJ173435.7+605203, WD0106-328, WD1133-528, WD1226+110, WD1244+498, WD1415+234, WD2105-820 ------------------------------------------------------------------------------------------------------------------------------------