SOFIA. Science Operations of an Airborne Observatory

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1 Science Operations of an Airborne Observatory Dr.-Ing. Thomas Keilig Deutsches Institut (DSI) University of Stuttgart Pfaffenwaldring 29, Stuttgart, Germany 1

2 What is? S tratospheric O bservatory bservatory F or F I or nfrared I A nfrared stronomy A stronomy 2

3 What is? is a joint U.S./German project: 80% NASA (National Aeronautics and Space Administration) 20% DLR (German Aerospace Agency) science missions are executed by: USRA (Universities Space Research Association) DSI (German Institute) Costs and Observing Time are shared by the United States (80%) and Germany (20%). 3

4 A) from ground based telescopes: Why Airborne Astronomy? B) from in ft (13,7 km) altitude: Wavelengths are blocked by absorption in earth s atmosphere due to water vapor Wavelength [µm] observes the Near-, Mid- and Far-InfraRed (1 to 300 µm) 4

5 The Observatory From the basic airplane Boeing 747SP Mission Director Work Station Science Instrument Control Stations, Telescope Operator Console to the airborne observatory. Pressure Bulkhead Science Instrument Open Cavity (door not shown) 2.7 m Telescope 5

6 VLT Construction 6

5 m (to allow un-vigneted chopping) Mass ~17 t Spherical bearing allows to move freely in all

7 The Telescope The Telescope: Cassegrain with Nasmyth Tube, f/19.6 Primary Mirror Ø = 2.7 m effective aperture Ø = 2.5 m (to allow un-vigneted chopping) Mass ~17 t Spherical bearing allows to move freely in all three axes (EL, XEL, LOS) +/- 2.5 Inertial stabilized by Fiber Optical Gyroscopes (FOG) Pointing stability: 0.2 arcsec rms Elevation range: (view limited by door system) 7

8 The Telescope Counter Weights Science Instrument Cabin Side Pressure Bulkhead Nasmyth Tube Pointing Control System (incl. fiber optical gyroscopes) Secondary Mirror (M2) Vibration Isolation System Cavity Side Tertiary Mirror, dichroic (M3-1) Tertiary Mirror (M3-2) Primary Mirror (M1) 8

Nasmyth Tube Nasmyth Tube Bearing Bearing Sphere Sphere C.G.

9 Optical Path Science Instrument Focal Plane Counter Weight Cabin Side Focal Plane Imager Pressure Bulkhead Hydraulic System Motors Brakes Nasmyth Tube Nasmyth Tube Bearing Bearing Sphere Sphere C.G. Guiding Cameras Vibration Isolation System M2 Cavity Side M3-2 M3-1 (dichroic) Primary Mirror M1 9

10 First Light Instrument FORCAST (Faint Object infrared CAmera for the Telescope) Principal Investigator: Dr. Terry Herter, Cornell University, Ithaca, New York λ = 5-25 µm & µm FOV: 3.2 x 3.2 Spectral resolution:

11 First Light (26.Mai 2010) 5.4 µm, 24 µm, 37 µm 11

12 Instrument R/λ graph 1 st Generation Science Instruments FIFI LS 12

13 1 st Generation Science Instruments Name Meaning Description PI Institution Country FORCAST GREAT FLITECAM HIPO EXES FIFI-LS HAWC+ Faint Object InfraRed Camera for the Telescope German Receiver for Astronomy at Terahertz Frequencies First Light Infrared Test Experiment Camera High-speed Imaging Photometer for Occultation Echelon-Cross- Echelle Spectrograph Field Imaging Far- Infrared Line Spectrometer High-resolution Airborne Wideband Camera Mid-Infrared camera and grism spectrometer 2-Chanel heterodyne spectrometer Near-Infrared camera and grism spectrometer CCD imaging photometry at visual / NIR wavelengths High resolution Mid-Infrared echelon (slit) spectrometer spatial and spectral slit spectroscopy 2 wavelengths Far-Infrared bolometer camera (and polarimeter) T. Herter Cornell University, Ithaca, NY R. Güsten I. McLean MPIfR, Max-Planck Institut für Radioastronomie, Bonn UCLA Division of Astronomy and Astrophysics, Los Angeles, CA T. Dunham Lowell Observatory, Flagstaff, Arizona M. Richter UC Davis, built at NASA Ames Research Center A. Krabbe Univ. of Stuttgart, Stuttgart D. Dowell JPL, Pasadena, CA Wavelength [µm] Spectral Resolution 1 st (F)Light on USA Germany USA USA USA , 10 4, Germany USA

14 Last updated: June 29, 2013 Science Mission Directorate (SMD) Herschel cryogen depleted in April Spacecraft decommissioned by ESA on June 17, GALEX NASA science mission ended February Caltech mission May April 2013, decommissioned June 29,

15 Observing Cycles Observing Cycles Calendar year 2013: Observing Cycle 1 (278 Research Hours) Calendar year 2014: Observing Cycle 2 (335 Research Hours) and so on (increasing up to full ability of ~1000 Research Hours each year) Observing Cycles are in coincidence with the calendar year. Call for Proposals (CfP) There will be a separate U.S. and German Proposal Call released in each spring, ideally supported by a CfP Workshop : U.S. Call for Proposals by USRA (worldwide open, German PIs excluded) German Call for Proposals by DSI (for German PIs only) There Proposal will deadlines be a are Observer's in summer. Handbook online for each cycle: Two independent Time Allocation Committees (TAC) meet to review the proposals. Now the difficult process of Science Flight Planning starts 15

16 Observation Scheduling and Flight Planning Facts to be considered (unlike on ground-based observatories): The telescope looks out of the port side of the aircraft. the azimuth of the target dictates the aircraft heading. Restricted air space needs to be avoided. Object to be observed needs to be in the elevation range of observing a target that culminates above 70 (~11 hrs above 23 ) night is split into two observing windows of only ~3 hours. Because the aircraft is moving, the observatory s longitude and latitude are changing constantly. Flight planning can be used to adjust targets elevation. After an observing night, needs to return to the airport it departed from: Palmdale (CA) or Christchurch (NZ). Minimization of dead legs. Minimize down time due instrument swaps. 16

17 Flight Paths Palmdale (CA) 17

18 Flight Paths Geographic Distribution of Science Flights ( ) 18

Data Cycle System Investigator Science Data Products Investigator Query & Retrieve Data Analysis & Prop Support Proposal Process New Science

Data Science Instrument Reduced Data Science Integration Lab Mission Datasets Observatory Observing Plans Archive & Reduce Data Joint Observatory

19 Data Cycle System Investigator Science Data Products Investigator Query & Retrieve Data Analysis & Prop Support Proposal Process New Science Instruments Annual Operating Plan Tools for Annual Lifecycle Archive Observatory Maintenance & Operations Planning Database Raw Data, House Keeping Data Science Instrument Reduced Data Science Integration Lab Mission Datasets Observatory Observing Plans Archive & Reduce Data Joint Observatory Operations Detail Observing Plan Raw Data, House Keeping Data Data Manifests Develop Flight Plan Execute Observations Mission Plans Science Center Staff Airborne System 19

Sgr A*- CND blue 19.7 µm green 31.5 µm red 37.

varies from left (central structures) to right (to emphasize CNR) Almost perfect ring R~ 1.

gradient across ring: Internal heating source Probably by young stars interior to the ring FORCAST: T.

20 Sgr A*- CND blue 19.7 µm green 31.5 µm red 37.1 µm Science Highlights Multicolor image of the circumnuclear disk (CND) at the Galactic Center Brightness varies from left (central structures) to right (to emphasize CNR) Almost perfect ring R~ 1.5 pc around the MO Black Hole Thickness/Diameter only ~ 1/10; inclination wrt plane of sky 67º Color gradient across ring: Internal heating source Probably by young stars interior to the ring FORCAST: T. Herter, M. Morris et al R. M. Lau, T. L. Herter, M. R. Morris, E. E. Becklin, J. D. Adams /FORCAST Imaging of the Circumnuclear Ring at the Galactic Center The Astrophysical Journal, Volume 775, Number 1 20

21 Science Highlights R. M. Lau, T. L. Herter, M. R. Morris, E. E. Becklin, J. D. Adams /FORCAST Imaging of the Circumnuclear Ring at the Galactic Center The Astrophysical Journal, Volume 775, Number 1 FORCAST: T. Herter, M. Morris et al

GREAT (German REceiver for Astronomy at Terahertz frequencies) Heterodyne Spectrometer PI: R. Güsten, guesten@mpifr.

22 GREAT (German REceiver for Astronomy at Terahertz frequencies) Heterodyne Spectrometer PI: R. Güsten, Max-Planck Institut für Radioastronomie Detector: dual channel mixer (HEB); µm ( THz) Resolving power = 10 8 Targets: Galactic and extragalactic ISM, circumstellar shells Channels Astronomical lines THz : [NII], CO, (13)CO, HCN, H2D THz : [CII], CO THz: HD, OH(2P3/2), CO, (13)CO System temperature T~1500 K at 158 µm High frequency upgrade at 4.7 THz expected in Oct 2013 for OI (63 µm). In 2015: upgreat with 14 pixels at 1.9 THz and 7 pixels at 4.7 THz 22

23 GREAT Science Mapping of [CII] and CO in molecular cloud M17 SW - [CII] - CO molecular mass: ~10 4 MSolar GREAT 23

Parise et al. Special Issue (April 2012) Detection of OD towards the low-mass protostar Confirmation of transient nature of the circum-nuclear disk M. A. Requena-Torres et al.

24 First Papers Early Science with GREAT: 22 GREAT Papers A&A Vol. 542 Special Issue (June 2012) Discovery of interstellar mercapto radicals (SH) Early Science with FORCAST: 8 FORCAST D. A. Neufeld Papers et al. ApJ Letters Vol. 749 B. Parise et al. Special Issue (April 2012) Detection of OD towards the low-mass protostar Confirmation of transient nature of the circum-nuclear disk M. A. Requena-Torres et al. Globules and pillars seen in the [CII] 158 μm line with N. Schneider et al. : First science highlights and future science F. Wyrowski potential et al. AN 334, No. 6 (July 2013) Ammonia absorption as a probe of infall in high-mass star forming clumps The structure of hot gas in Cepheus B B. Mookerjea et al. 24

25 Pluto Occultation 23. June 2011 Pluto s nadir Dwarf planet Pluto occulted a star met the shadow of Pluto in the mid-pacific HIPO and s Fast Diagnostic Camera (FDC) observed the occultation simultaneously Dunham, Wolf et al

merged, combined light During occultation: Pluto and star merged, only Pluto light seen

26 Image sequence from the FDC: Pluto Occultation Pluto (circled) is 13 from the star, 200 min. before the occultation FDC (visual) Just before occultation: Pluto and star merged, combined light During occultation: Pluto and star merged, only Pluto light seen HIPO (NIR) After occultation: Pluto and star merged, combined light Dunham, Wolf et al

27 Pluto Occultation s mobility was crucial for this successful observation: - duration of occultation ~120 sec - central line reached <50 km Results published last week: M. J. Person, E. W. Dunham et al. The 2011 June 23 stellar Occultation by Pluto: Airborne and Ground Observations The Astronomical Journal, 146:83 (15pp), 2013 October discussing: - Astrometry and Prediction of the Occultation - Data and Light Curves measured - Pluto s Atmosphere structure - Evolution of Pluto s Atmosphere as Pluto gets more distant from the sun 27

28 NZ Deployment 1 st Southern Hemisphere Deployment Christchurch (NZ) July 12 th August 3 rd 2013 with GREAT 28

29 NZ Deployment Why Southern Hemisphere Deployment? To observe key regions that are either unavailable or poorly observed from Palmdale: The Southern Milky Way, Large Magellanic Cloud, Small Magellanic Cloud and the Galactic Center were observed with GREAT. Prominent targets like NGC3603 and BHR71 that are well studied in the optical, but for which we have no FIR data yet. Better (longer, higher elevation) visibility of targets in the inner Galaxy. Water vapor at LOS is <5 microns in Antarctic regions. Observations during the NZ deployment: In total 25 science projects were carried out in 9 flights. 7 science projects were carried out to study the physics of the interstellar gas in the Magellanic Clouds in CII, NII, and CO. CO (11-10), CO (13-12) and CO (16-15) excitation across the massive gas disk rotating around & feeding the black hole in the Galactic Center. 29

Mobility: can observe anywhere, anytime, on short notice

30 Summary: Why? Infrared transmission: in the Stratosphere the transmission is >80% for wavelengths from 1 to 1000 µm Instrumentation: wide complement rapidly interchangeable state-of-the art Global Mobility: can observe anywhere, anytime, on short notice Lifetime: is built for 20 years and will be one of the primary facilities for FIR and sub-mm astronomy for many years 30

31 Thank you for your attention! Questions? 31

32 More Information about can be found NASA homepage: USRA homepage: DSI homepage: Other:

CYCLE 1 SCIENCE STATUS AND HOW TO PROPOSE TIME ON SOFIA. Helen J. Hall¹, Erick T. Young¹, Hans Zinnecker²,³

CYCLE 1 SCIENCE STATUS AND HOW TO PROPOSE TIME ON SOFIA Helen J. Hall¹, Erick T. Young¹, Hans Zinnecker²,³ ¹SOFIA Science Center, Universities Space Research Association, NASA Ames Research Center MS 232-12,