DSS-28: a novel wide bandwidth radio telescope devoted to educational outreach

We have recently equipped the 34-meter DSS-28 radio telescope at the Goldstone Deep Space Communications Complex with a novel wide bandwidth radiometer and digital signal processor as part of the Goldstone Apple Valley Radio Telescope (GAVRT) educational outreach program operated by the Jet Propulsion Laboratory and the Lewis Center for Educational Research. The system employs a cryogenically cooled wide bandwidth quad-ridge feed and InP low noise amplifiers to achieve excellent noise performance from 2.7 to 14 GHz; a fractional bandwidth better than 4:1. Four independently tunable dual-polarization receivers each down-convert a 2 GHz block to baseband, providing access to 8 GHz of instantaneous bandwidth. A flexible FPGA-based signal processor has been constructed using CASPER FPGA hardware and tools to take advantage of this enormous bandwidth. This system demonstrates many of the enabling wide bandwidth technologies that will be crucial to maximizing the utility of future large centimeter-wavelength arrays, in particular the Square Kilometer Array. The GAVRT program has previously used narrow bandwidth total power radiometers to study flux variability of quasars and the outer planets. The versatility of DSS-28 will enable other projects including spectroscopy and SETI. Finally, the wide instantaneous bandwidth available makes this system uniquely suited for studying transient radio pulses. A configuration of the digital signal processor has been developed which provides the capability of recording a burst of raw baseband voltage data triggered by a real-time incoherent dedispersion system which is very sensitive to pulses from a known source, such as the Crab Nebula pulsar

Keys of a Mission to Uranus or Neptune, the Closest Ice Giants

Uranus and Neptune are the archetypes of "ice giants", a class of planets that may be among the most common in the Galaxy. They are the last unexplored planets of the Solar System, yet they hold the keys to understand the atmospheric dynamics and structure of planets with hydrogen atmospheres inside and outside the solar system

Neptune Odyssey: A Flagship Concept for the Exploration of the Neptune–Triton System

The Neptune Odyssey mission concept is a Flagship-class orbiter and atmospheric probe to the Neptune-Triton system. This bold mission of exploration would orbit an ice-giant planet to study the planet, its rings, small satellites, space environment, and the planet-sized moon Triton. Triton is a captured dwarf planet from the Kuiper Belt, twin of Pluto, and likely ocean world. Odyssey addresses Neptune system-level science, with equal priorities placed on Neptune, its rings, moons, space environment, and Triton. Between Uranus and Neptune, the latter is unique in providing simultaneous access to both an ice giant and a Kuiper Belt dwarf planet. The spacecraft - in a class equivalent to the NASA/ESA/ASI Cassini spacecraft - would launch by 2031 on a Space Launch System or equivalent launch vehicle and utilize a Jupiter gravity assist for a 12 yr cruise to Neptune and a 4 yr prime orbital mission; alternatively a launch after 2031 would have a 16 yr direct-to-Neptune cruise phase. Our solution provides annual launch opportunities and allows for an easy upgrade to the shorter (12 yr) cruise. Odyssey would orbit Neptune retrograde (prograde with respect to Triton), using the moon's gravity to shape the orbital tour and allow coverage of Triton, Neptune, and the space environment. The atmospheric entry probe would descend in ~37 minutes to the 10 bar pressure level in Neptune's atmosphere just before Odyssey's orbit-insertion engine burn. Odyssey's mission would end by conducting a Cassini-like "Grand Finale,"passing inside the rings and ultimately taking a final great plunge into Neptune's atmosphere

Analogy: The vital talent that fuels our minds

Hofstadter, D., & Sander, E. (2013). Analogy: The vital talent that fuels our minds. New Scientist, 2915, 30-3

Pourquoi fonctionnons-nous par analogie

Invité à l’émission Autour de la question. Caroline Lachowski. Radio France International. Pourquoi fonctionnons-nous par analogie ? Emission du 28 février 2013 http://www.rfi.fr/emission/20130228-1-pourquoi-fonctionnons-nousanalogi

Surfaces and Essences: Analogy as the fuel and fire of thinking

International audienc

Analogy: The vital talent that fuels our minds

Hofstadter, D., & Sander, E. (2013). Analogy: The vital talent that fuels our minds. New Scientist, 2915, 30-3

L’Analogie : coeur de la pensée

International audienc

Pourquoi fonctionnons-nous par analogie

Invité à l’émission Autour de la question. Caroline Lachowski. Radio France International. Pourquoi fonctionnons-nous par analogie ? Emission du 28 février 2013 http://www.rfi.fr/emission/20130228-1-pourquoi-fonctionnons-nousanalogi