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In 1979, NASA established the Great Observatory program, which included four telescopes (Hubble, Compton, Chandra, and Spitzer) to explore the Universe. The Spitzer Space Telescope was launched in 2003 into solar orbit, gradually drifting away from the Earth. Spitzer was operated very successfully until 2020 when NASA terminated observations and placed the telescope in safe mode. In 2028, the U.S. Space Force has the opportunity to demonstrate satellite servicing by telerobotically reactivating Spitzer for astronomical observations, and in a separate experiment, carry out novel Space Weather research and operations capabilities by observing solar Coronal Mass Ejections. This will be accomplished by launching a small satellite, the Spitzer-Resurrector Mission (SRM), to rendezvous with Spitzer in 2030, positioning itself around it, and serving as a relay for recommissioning and science operations. A sample of science goals for Spitzer is briefly described, but the focus of this paper is on the unique opportunity offered by SRM to demonstrate novel Space Weather research and operations capabilities.

We present several corrections for point-source photometry to be applied to data from the Infrared Array Camera (IRAC) on the Spitzer Space Telescope. These corrections are necessary because of characteristics of the IRAC arrays and optics and the way the instrument is calibrated in flight. When these corrections are applied, it is possible to achieve a [image]2% relative photometric accuracy for sources of adequate signal-to-noise ratio in an IRAC image.

This is a collection of invited talks and oral contributions presented by the leading scientists in their fields, summarizing the most recent progress of, and new prospects for, nuclear physics research.It covers a broad range of the recent developments in nuclear physics: reactions between massive nuclei leading to superheavy element formation; radioactive beams and neutron-rich systems; exotic nuclei and nuclear astrophysics; new states of nuclear matter.Contents:Opening Talk: Nuclear Structure at Border Lines (Yu Ts Oganessian)Hard Photons: A Probe of Dynamical Effects in Heavy Ion Collisions at Intermediate Energy (R Alba et al.)Studying Exotic Nuclei Through Direct Reactions (Y Blumenfeld)Isospin Effects on Instabilities and Fragmentation Mechanisms (M Colonna et al.)New Opportunities with Beams of Rare Isotopes in the US (C K Gelbke)Preliminary Results and Future Activities at the GARFIELD Apparatus (F Gramegna et al.)Mean-Field Calculations of Super-Heavy Elements (P H Heenen)Recent Experiments and Plans for the Synthesis of Superheavy Elements at the GSI SHIP (S Hofmann)Nuclear Fission at Border Lines (M G Itkis et al.)Many-Body Theory at Extreme Isospin (H Lenske et al.)Probing Correlations in Many-Body Haloes (F M Marqués Moreno)Theoretical Approaches and Experimental Evidences for Liquid-Vapor Phase Transitions in Nuclei (L G Moretto et al.)Study of Halo-Structure in Radioactive He and Li Nuclei with Proton Elastic Scattering (A V Dobrovolsky et al.)Effects of the Shell Structure in Reactions Leading to the Same Compound Nucleus or Different Isotopes (A K Nasirov et al.)New Magic Number, N=16, Near the Neutron Drip Line (A Ozawa)Experiments on Super-Heavy Nuclei at GANIL (J Péter et al.)Thermodynamics of Hot Nuclei: Multifragmentation and Phase Transition (M F Rivet)Structure and Properties of Superheavy Nuclei (I Muntian A Sobiczewski)Backtraced Neutron Multiplicities and Capture Dynamics in the Superheavy Region (L Stuttgé et al.)Astrophysical S Factors from Asymptotic Normalization Coefficients (R E Tribble et al.)and other papersReadership: Researchers in nuclear physics and astrophysics.

We present several corrections for point-source photometry to be applied to data from the Infrared Array Camera (IRAC) on theSpitzer Space Telescope.These corrections are necessary because of characteristics of the IRAC arrays and optics and the way the instrument is calibrated in flight. When these corrections are applied, it is possible to achieve a∼2% ∼ 2 % relative photometric accuracy for sources of adequate signal-to-noise ratio in an IRAC image.

The Infrared Array Camera (IRAC) on theSpitzer Space Telescopeis absolutely calibrated by comparing photometry of a set of A stars near the north ecliptic pole to predictions based on ground‐based observations and a stellar atmosphere model. The brightness of point sources is calibrated to an accuracy of 3%, relative to models for A‐star stellar atmospheres, for observations performed and analyzed in the same manner as for the calibration stars. This includes corrections for the location of the star in the array and the location of the centroid within the peak pixel. Long‐term stability of the IRAC photometry was measured by monitoring the brightness of A dwarfs and K giants (near the north ecliptic pole) observed several times per month; the photometry is stable to 1.5% (rms) over a year. Intermediate‐timescale stability of the IRAC photometry was measured by monitoring at least one secondary calibrator (near the ecliptic plane) every 12 hr while IRAC was in nominal operations; the intermediate‐term photometry is stable, with a 1% dispersion (rms). One of the secondary calibrators was found to have significantly time‐variable (5%) mid‐infrared emission, with a period (7.4 days) matching the optical light curve; it is possibly a Cepheid variable.

The Space Infrared Telescope Facility (SIRTF) is the fourth and final element in NASA's family of orbiting \"Great Observatories.\" SIRTF will offer order-of-magnitude improvements in capability over existing programs in the wavelength region between 3 and 180 microns. The combination of large-format detector arrays, with the intrinsic sensitivity of a cryogenic telescope, and the high sky visibility of a solar orbit, makes SIRTF an ideal instrument to carry out a number of very significant surveys to study the birth and evolution of galaxies in the early Universe. More than 75% of SIRTF's observing time will be available to the worldwide scientific community, with the first call for proposals in July, 2000. SIRTF will be launched in December 2001, with an anticipated lifetime of 5 years.

The Triangulum Spiral Galaxy Messier 33 offers unique insights into the building of a galactic disk. We identify spectacular arcs of intermediate age (0.6 Gyr − 2 Gyr) stars in the low-metallicity outer disk. The northern arc spans ~120 degrees in azimuth and up to 5 arcmin in width. The arcs are located 2-3 disk scale lengths from the galaxy centre (where 1 disk scale length is equivalent to 0.1 degrees in the V-band) and lie precisely where there is a warp in the HI profile of M33. Warps and infall are inextricably linked (Binney, 1992). We present spectroscopy of candidate stars in the outer northern arc, secured using the Keck I telescope in Hawaii. The target stars have estimated visual magnitudes as faint as V~ 25m. Absorption bands of CN are seen in all spectra reported in this review talk, confirming their carbon star status. Also presented are PAH emissivity radial profiles generated from IRAC observations of M33 using the Spitzer Space Telescope. A dramatic change of phase in the m = 2 Fourier component is detected at the domain of the arcs. M33 serves as an excellent example how the disks of spiral galaxies in our Universe are built: as dynamically open systems, growing from the inward, outward.

WISH is a new space science mission concept whose primary goal is to study the first galaxies in the early universe. The primary science goal of the WISH mission is to push the high-redshift frontier beyond the epoch of reionization by utilizing its unique imaging and spectrocopic capabilities and the dedicated survey strategy. WISH will be a 1.5m telescope equipped with a 1000 arcmin2 wide-field Near-IR camera to conduct unique ultra-deep and wide-area sky imaging surveys in the wavelength range 1 - 5 μm. A spectroscopic mode (Integral-Field Unit) in the same Near-IR range and with a field of view of 0.5 - 1 arcmin and a spectral resolution R = 1000 is also planned. The difference between WISH and EUCLID in terms of wavelength range explains why the former concentrates on the reionization period while the latter focuses on the universe at z < 3. WISH and JWST feature different instantaneous fields of view and are therefore also very complementary.