Flight Planning for 1st Light

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Flight Planning for 1st Light

Allan Meyer and Eric Becklin

SSSC 29 Sept 2009

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Flight Planning for “TA charact., 1st light”

• 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

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Location of Geographic Limits

• 200 nm radius limit

• Off-shore limit

Mexico border

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Flight Plan Science Constraints

• 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)

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Getting a List of Appropriate IR Stars

• 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.SIMBAD ident.

typeR.A.

(2000)Dec. Gal.

long.244.4

Gal. lat.

V Kspec. type

F12 / F25

l Pup

Em*

7 43 48.47 -28 57 17.4 -2.54 4.0 2.5A3Iab:

1.8

12 Lib

Star

14 54 20.13 -24 38 31.9 335.5 30.35 5.3 2.2K2/K3III

4.1

13 PsA

Star

22 4 23.84 -29 54 59.5 18.5 -53.40 6.5 2.0K5III

4.9

24 Cap

*in**

21 7 7.67 -25 0 21.1 22.0 -40.01 4.5 0.5K7III

3.8

27 Sco

Star

16 57 11.18 -33 15 34.2 350.5 6.07 5.5 1.6K5III

4.2

36 Lib

Star

15 34 37.32 -28 2 49.1 341.5 22.35 5.1 1.9K4III

3.7

43 Oph

Star

17 23 21.59 -28 8 34.2 358.0 4.54 5.3 1.5K5III

4.4

49 Hya

Star

14 6 22.30 -26 40 56.5 323.0 33.25 3.3 0.8K1III-IV

4.5

50 Hya

Star

14 12 46.02 -27 15 40.3 324.3 32.21 5.1 2.4K3III

4.1

52 Eri

Star

4 35 33.04 -30 33 44.4 231.0 -41.31 3.8 1.6G8IIIa

3.8

AF For

PulsV*

3 8 37.52 -26 26 46.9 219.6 -59.47 8.6 2.1M5III

3.5

AH Sco

semi-regV*

17 11 17.02 -32 19 30.7 353.1 4.27 7.5 0.4M4III:

1.8

AI For

V*

3 19 34.91 -24 7 22.4 216.2 -56.59 5.7 1.1M1III

3.7

AK Pyx

Irregular_V*

8 48 14.63 -28 38 19.7 252.0 9.35 6.5 0.5M5III

2.7

AL Pyx

Irregular_V*

9 1 6.28 -27 30 56.7 252.9 12.27 7.2 2.4M1III

3.9

alf Sco

semi-regV*

16 29 24.46 -26 25 55.2 351.9 15.06 1.1 ~M1.5Iab-b

4.6

Alpha PsA

V*

22 57 39.05 -29 37 20.1 20.5 -64.91 1.2 ~A4V

3.8

AM For

semi-regV*

3 43 10.03 -31 1 9.4 229.4 -52.51 7.2 1.4M4III

3.7

AO Pyx

Irregular_V*

9 14 47.65 -33 40 56.5 259.6 10.41 8.8 2.1M5/M6III

3.5

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Candidate Targets for Feasibility Trials

• 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

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CPIRSS F(12 µm) > 5 Jy, -34° < Dec. < -24°

-36°

-34°

-32°

-30°

-28°

-26°

-24°

-22°

-20°

024681012141618202224Right Ascension (hrs, J2000)

Decli

nati

on

(J2

00

0)

Sky Distribution

QuickTime™ and a decompressor

are needed to see this picture.

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

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Feasibility: example TA char. Flight plan

ETD: 0320Z Mar. 15, 2010

ETE: 06+50

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Summary of Observing Legs

Leg no. Object V M F(12µm)Leg

DurationObject elevation

range

4 Saturn 0 30 m 19° - 25°

5 S Cep 7.5 -1.7 383 Jy 24 m 23°

7 HIP 43093 7.2 +1.8 20 Jy 45 m 24° - 23°

9 NGC 6543 9 +7 8 Jy 35 m 22° - 25°

10 NSV 4862 4.3 +1 20 Jy 45 m 23°

12 Gamma Cep 4.2 ~+0.7 21 Jy 37 m 23°

14 W Hya 7.5 - 3.9 4200 Jy 35 m 22° - 24.5°

16 HIP 11978 6,8 +1.1 12 Jy 30 m 23° - 22°

Sum of observing leg durations = 4.7 h

Net time with objects in 22° - 24° elev. range ~4.1 h

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“1st Light” & Short Science: availability of M42, Sgr A (winter / spring )

M 42, Sgr A Max. Leg Duration vs. Date( TA Elev. Range 23° - 30° )

0

10

20

30

40

50

60

70

80

90

1-Jan 15-Jan 29-Jan 12-Feb 26-Feb 12-Mar 26-Mar 9-Apr 23-Apr 7-May

Date

Max.

Leg D

ura

tion (

23°

- 30°)

M 42 setting

M 42 rising

M 42 rsing & setting

Sgr A (rising)

• 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.)