SETI Public Mailing List: SETI public: Extrasolar carbon planets

>Paper: astro-ph/0504214

>Date: Fri, 8 Apr 2005 20:12:45 GMT (36kb)

>Title: Extrasolar Carbon Planets

>Authors: Marc J. Kuchner (Princeton), S. Seager (Carnegie/DTM)

>Comments: 17 pages, 2 figures, submitted to ApJL

>\\

> We suggest that some extrasolar planets <~ 60 Earth masses will form

>substantially from silicon carbide and other carbon compounds. Pulsar planets

>and low-mass white dwarf planets are especially good candidate members of this

>new class of planets, but these objects could also conceivably form around

>stars like the Sun. This planet-formation pathway requires only a factor of two

>local enhancement of the protoplanetary disk's C/O ratio above solar, a

>condition that pileups of carbonaceous grains may create in ordinary

>protoplanetary disks. Hot, Neptune-mass carbon planets should show a

>significant paucity of water vapor in their spectra compared to hot planets

>with solar abundances. Cooler, less massive carbon planets may show

>hydrocarbon-rich spectra and tar-covered surfaces. The high sublimation

>temperatures of diamond, SiC, and other carbon compounds could protect these

>planets from carbon depletion at high temperatures.

>\\ ( http://arXiv.org/abs/astro-ph/0504214 , 36kb)

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>Paper: astro-ph/0504231

>Date: Mon, 11 Apr 2005 02:56:29 GMT (845kb)

>Title: Observing Near Earth Asteroids with a Small Telescope

>Authors: Ovidiu Vaduvescu

>Comments: 17 pages including two figures. Published in Romanian Astronomical

> Journal

>Journal-ref: RoAJ, 14/2 2004, 15/1 2005

>\\

> Even from a light polluted city it is possible to observe Near Earth

>Asteroids (NEAs) at opposition using a small telescope equipped with a CCD

>camera. In this paper, we will overview first the major NEA programs,

>continuing with planning the observations and the data reduction. Second, we

>will present a NEA follow-up program carried out on the 60-cm telescope at York

>University Observatory in Toronto, Canada. Part of this program, five NEAs have

>been observed during ten nights. Their astrometric and photometric data were

>reduced and sent to the Minor Planet Centre, following which an observatory

>code was assigned and four batches have been included in the NEODyS database

>and MPC Circulars. The results are applicable to any other small facility.

>\\ ( http://arXiv.org/abs/astro-ph/0504231 , 845kb)

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>Paper: astro-ph/0504240

>Date: Mon, 11 Apr 2005 13:59:54 GMT (74kb)

>Title: Evidence for Radio Detection of Extensive Air Showers Induced by Ultra

> High Energy Cosmic Rays

>Authors: D. Ardouin, A. Bell\'etoile, D. Charrier, R. Dallier, T. Gousset, F.

> Haddad, J. Lamblin, P. Lautridou, O. Ravel, A. Lecacheux, L. Denis, P.

> Eschstruth, D. Monnier-Ragaigne

>Comments: 4 pages, 4 figures

>\\

> Firm evidence for a radio emission counterpart of cosmic ray air showers is

>presented. By the use of an antenna array set up in coincidence with ground

>particle detectors, we find a collection of events for which both time and

>arrival direction coincidences between particle and radio signals are observed.

>The counting rate corresponds to shower energies $\gtrsim 5\times 10^{16}$ eV.

>These results open overwhelming perspectives to complete existing detection

>methods for the observation of ultra high-energy cosmic rays.

>\\ ( http://arXiv.org/abs/astro-ph/0504240 , 74kb)

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SETI public: Extrasolar carbon planets - paper