Flight Planning for 1st Light

1. Flight Planning for 1st Light Allan Meyer and Eric Becklin SSSC 29 Sept 2009

2. TA characterization: pointing stability, other performance & functionality aspects potentially affected by flight environment “first light” image from FORCAST: not science, for demonstration purposes only. Will not drive any new requirements or schedule delays Development phase constraints on the aircraft, and the character of the “IR Sky” dictate & severely limit the content of feasible flight plans. (Probably also true for TA characterization without FORCAST) Aircraft Constraints: Door fully open but fixed at 23° elevation for TA char., 1st light 200 nautical mile radius limit from DAOF* Offshore limit ~50 miles No Mexico overflight => Dec. > -35° ~ 6 hour flight duration Sun at least ~10° below horizon 35K observing altitude, winter / spring, 2010 *late note: Platform Project is considering an increase of the radius limit Flight Planning for “TA charact., 1st light”

3. 200 nm radius limit Off-shore limit Location of Geographic Limits Mexico border

4. TA characterization Pointing stability Image quality (i.e. confirm diffraction limit  from HIPO Shack-Hartmann) Chopping performance 5 - 25 µm fast imaging (50 - 500 Hz) of IR bright stars (M <+2) “First light”: demonstration of science capability:Point source okay; one extended source could be attempted. TBD s, 5 - 40 µm IR bright stars for setup, fast imaging (TA char.), & demonstration of FORCAST performance. FIR bright extended source(s) (H II/SFRs, planet) for science demonstration. Trackable with current FPI, mag. limit ~12 (offset tracking or FFI tracking if needed) Flight Plan Science Constraints

5. The appropriate list of visible & mid-IR bright stars is the first step FORCAST sensitivity at ~500 Hz readout rate J. Adams (Cornell, Dec. ‘08) calculation for 16 MIRAC stds. At 508 Hz readout rate, S/N = 50 for 56 Jy at 5.35 µm Vega ( Lyr, M = 0, 158 Jy) S/N = 140 Lists from several online sources have been downloaded for trial use The best list appears to be based on the IRAS Point Source Catalog (PSC), with limits on 12 µm flux, 12µm/25µm flux ratio, & appropriate ID. Getting a List of Appropriate IR Stars

6. FORCAST 2006 “Design Reference Mission”: ~100 assorted galactic & extragalactic targets 28 calibration stars:  Boo,  Tau,  CMa, etc. N mag. ~0 to -4 NOAO list + UKIRT stds. + Cat. IR Obs. (Gezari) M<+1,  > -35° => N = 288 IRAS PSC (using CDS Vizier) + SIMBAD idents 12 µm flux > 25 µm flux for stellar sources Dec. strip for ~23° elevation west heading: -34° to -24° N ~ 250 to 310 depending on 12µm flux cutoff (e.g. 10 Jy, or gal. b modulated) Catalog of Pstns. of IR Stellar Sources (CPIRSS, Hindsley et al. 1994) IRAS PSC sources confidently identified as stars (Tycho, Hipparcos, etc.) Dec. -34° to -24°, F(12µm) > 5 Jy, & F(12µm) > F(25µm) => N = 263 Candidate Targets for Feasibility Trials

7. Sky Distribution FORCAST DRM (green), NOAO + UKIRT + CIO bright IR stars (M < +1), Dec. >-35°

8. Feasibility: example TA char. Flight plan ETD: 0320Z Mar. 15, 2010 ETE: 06+50

9. Summary of Observing Legs Sum of observing leg durations = 4.7 h Net time with objects in 22° - 24° elev. range ~4.1 h

10. “1st Light” & Short Science: availability of M42, Sgr A (winter / spring ) • M 42 available both rising & setting thru end of Jan. (8-hr flight can catch both.) • After that only one leg possible, limited by 23°- 30° elev. range to 40 minutes until ~Apr. 20. • Sgr A starts to become available in mid-March. (Leg duration limited to 50 min. by 200 nautical mile radius range limit.)