Abstract: We propose the Advanced Solar Coronal Explorer Mission (ASCE) to address three fundamental questions: 1) What physical processes heat coronal holes and drive the fast solar wind? 2) What physical processes heat coronal streamers and drive the slow solar wind? and 3) How are coronal mass ejections heated and accelerated? ASCE comprises a Large Aperture Spectroscopic and Polarimetric Coronagraph (SPC), a deployable mast that supports a remote external occulter and a high cadence Extreme Ultraviolet Imager (EUVI). The capabilities of the ASCE instrument far exceed their SOHO counterparts. Powerful spectroscopic diagnostic techniques are used to describe the coronal plasma in the regions where extended heating and acceleration of protons and heavy ions are known to occur. The ASCE payload is accommodated on a Spartan 400 Carrier to be deployed and retrieved by the Space Shuttle. Dr. Leonard Strachan is the project coordinator for Education and Public Outreach.

Abstract: Solar wind induced stresses in Earth’s magnetosphere cause dynamic and static currents, and energy, to flow along magnetic field lines into the polar ionosphere, generating the aurora. It is mysterious how magnetosphere-ionosphere (M-I) coupling works and generates the myriad of spatial and temporal structures in the aurora and M-I coupling regions. To achieve fundamental, predictive understanding of M-I coupling, we propose Auroral Multiscale Midex (AMM), a suite of four, identical, mini-satellites, in near-polar, ~7000 x ~600 km orbit, with inter-spacecraft separations of ~1 to ~1000 km. By simultaneously measuring magnetic and electric fields, waves, ions and electrons at multiple points, by unambiguously determining field-aligned currents, and by imaging the UV auroral context, AMM will: (1) characterize the structures and communications of M-I coupling; (2) measure the impedance of the mid-altitude coupling region; (3) determine the effects of ionospheric feedback, and (4) establish the relationships between coupling processes and magnetospheric generators.

Abstract: We propose a first-of-its-kind multiwavelength transient observatory called Swift for gamma-ray burst astronomy. It has the optimum capabilities for the next breakthroughs in determining the origin of GRBs and their afterglows and using bursts to probe the early Universe. It will also perform the first sensitive hard X-ray survey of the sky. A wide-field gamma-ray camera will detect ~1000 GRBs in 3 years to 5x fainter than BATSE. Sensitive narrow-field X-ray and UV/optical telescopes will be pointed at the burst location in 20 to 70 sec by an autonomously controlled "swift" spacecraft. For each burst, 0.3 - 2.5 arcsec positions will be determined and optical/UV/X-ray/gamma-ray spectrophotometry performed. On-board measurements of redshift will be done for 800 GRBs. Superb, low-cost instruments are proposed using existing flight-spare hardware and designs, combined with straight-forward development. Strong E/PO and follow-up programs are proposed to engage the public and astronomical community in Swift.

Abstract: The Next Generation Sky Survey (NGSS) is an experiment designed to provide an all sky survey of unprecedented sensitivity in the mid-IR band from 3.5 to 25 microns. This survey will provide catalogs and images which will have the same value to future large IR space telescopes such as the NGST that the POSS had for large ground-based optical telescopes. Scientific objectives to be addressed by NGSS include:

• The nature of and evolutionary history of Ultra-Luminous InfraRed Galaxies. NGSS should find the most luminous galaxy in the Universe.
• The faintest, coldest stars. NGSS is sensitive to old, cold brown dwarf stars with temperatures below 1056 K (Gliese 229B). These stars should outnumber the hotter L dwarfs, which outnumber the M dwarfs -- so NGSS should discover the closest star to the Sun.
• The evolution of circumstellar dust and debris disks.
• Radiometric diameters and albedos for almost all known asteroids.

Abstract: FAME is a space astrometry mission that offers the unique opportunity to measure the positions, proper motions, parallaxes and photometry of 40,000,000 stars brighter than V=15th magnitude to unprecedented accuracy. The astrometric accuracy will range between 30 and 300 microarcseconds, dependent on the magnitude. The photometry will give millimagnitude accuracies in four colors. The instrument will rotate in a scanning survey pattern similar to the Hipparcos project. The spacecraft will be geosynchronous with the precession primarily driven by solar radiation pressure. The resulting data will provide a definitive calibration of absolute luminosities of "standard candles" for defining distance scales, calibrate the absolute luminosities of solar neighborhood stars, provide a definitive determination of the frequency of solar-type stars orbited by brown dwarfs and giant planets, provide proper motions and distances for individual stars in star forming regions, assess the abundance of dark matter in the galactic disk, and become an astrometric and photometric catalog. This mission is a complement to and source of input data for the Space Interferometry Mission.

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NASA Headquarters Responsible Office: Code SR
Last Updated: 1 March 1999
Author: Paul Hertz (Code SR)