The Infrared Spectrograph (IRS) is one of three science instruments on the Spitzer Space Telescope. The IRS comprises four separate spectrograph modules covering the wavelength range from 5.3 to 38 m with spectral resolutions, R ¼ k=Ák % 90 and 600, and it was optimized to take full advantage of the very low background in the space environment. The IRS is performing at or better than the prelaunch predictions. An autonomous target acquisition capability enables the IRS to locate the mid-infrared centroid of a source, providing the information so that the spacecraft can accurately offset that centroid to a selected slit. This feature is particularly useful when taking spectra of sources with poorly known coordinates. An automated data-reduction pipeline has been developed at the Spitzer Science Center.

We describe Cornell's near-infrared camera system PHARO (Palomar High Angular Resolution Observer) built for use with the JPL Palomar Adaptive Optics System on the 5 m Hale telescope. PHARO uses a HgCdTe HAWAII detector for observations between 1 and 2.5 mm wavelength. An all-reflecting 1024 # 1024 optical system provides diffraction-limited images at two scales, 25 and 40 mas pixel Ϫ1 , plus a pupil imaging mode. PHARO also has a coronagraphic imaging capability and a long-slit grism spectroscopy mode at resolving power ≈1500. The instrument has been in use with the AO system at Palomar since early 1998.

We present images of the Galactic center in the dust continuum at 31.5 and 37.7 km obtained with the Kuiper WideÐeld Infrared Camera on the Kuiper Airborne Observatory. The raw images have a spatial resolution of and cover a region roughly 10@ (R.A.) by 24@ (decl.) in extent. Here we discuss the D8A .5 innermost (6.9 ] 9.1 pc) regions roughly centered on Sagittarius A*, where the high signal-to-2@ .8 ] 3@ .6 noise ratio permits image restoration to spatial resolution at 31.5 and 37.7 km, respectively. D3A .6È5A .7 These images clearly delineate the warm dust in the "" minispiral ÏÏ but also show an elliptical structure centered on Sgr A* and intersecting the minispiral at the western arc that we identify as the photodissociated inner rim of the circumnuclear disk (CND) or ring. This is the Ðrst image of the complete disk and the Ðrst image of both the minispiral and CND in a single tracer, thereby permitting detailed studies of the intimate association between these two structures. The 31.5/37.7 km color temperature map indicates that most of the far-UV Ñux required to heat the dust grains must come from centrally located sources. The cluster of He I emission-line stars recently identiÐed near Sgr A* is sufficient to provide half the heating for the far-IR ring and minispiral structures, the balance likely being provided by O and B stars associated with the cluster. We also Ðnd D16 color temperature peaks distributed within the CND that we suggest are the locations of early type (B4 to O9) main-sequence stars. To match the observed far-IR Ñuxes from the ring, we require an unusually high 30È40 km dust grain emissivity and/or an usually high UV albedo.The far-IR morphology is reproduced by a simple model : an inclined (i D 65¡), slightly elliptical (e D 0.06) torus with one focus at Sgr A* and two streamers on parabolic orbits with foci at Sgr A*. The torus has an inner radius of 1.58 pc, is D0.4 pc thick, and consists of clumpy cloudlets with characteristic sizes less than 0.15 pc. The northern streamer is identiÐed with the northern arm, and the east-west (EW) streamer is identiÐed with the bar and eastern arm structures seen in both their [Ne II] Ðne-structure line emission and the radio continuum. The northern arm is traced in the far-IR continuum from regions D1.4 pc outside of the far-IR ring to its apparent intersection with the EW streamer. The eastern CND is not detected in the radio continuum because of extinction by the intervening northern arm, which therefore must be nearly in the plane of the CND. Extensions of the EW streamer outside of the CND are apparent to the east and especially to the northwest. The EW streamer lies D85¡ out of the plane of the CND and is on a parobolic orbit focused on Sgr A* at a distance of 0.33 pc, with its apex well in front of or behind Sgr A*.

The Stratospheric Observatory for Infrared Astronomy (SOFIA) completed its first light flight in May of 2010 using the facility mid-infrared instrument FOR-CAST. Since then, FORCAST has successfully completed thirteen science flights on SOFIA. In this paper we describe the design, operation and performance of FORCAST as it relates to the initial three Short Science flights. FORCAST was able to achieve near diffraction-limited images for λ > 30µm allowing unique science results from the start with SOFIA. We also describe ongoing and future modifications that will improve overall capabilities and performance of FOR-CAST.

We present new 37.7 µm far-infrared imaging of the infrared luminous (L IR ∼ 5.16×10 11 L ⊙ ) interacting galaxy Arp 299 (= IC 694 + NGC 3690). We show that the 38 µm flux, like the 60 and 100 µm emission, traces the luminosity of star forming galaxies, but at considerably higher spatial resolution. Our data establish that the major star formation activity of the galaxy originates from a point source in its eastern component, IC 694, which is inconspicuous in the optical, becoming visible only at the near and midinfrared. We find that IC 694 is two times more luminous than NGC 3690, contributing to more than 46% of the total energy output of the system at this wavelength. The spectral energy distribution of the different components of the system clearly shows that IC 694, has 6 times the infrared luminosity of M82 and it is the primary source responsible for the bolometric luminosity of Arp 299.