Results 31 to 40 of about 4,639 (216)
Possible Ribose Synthesis in Carbonaceous Planetesimals
The origin of life might be sparked by the polymerization of the first RNA molecules in Darwinian ponds during wet-dry cycles. The key life-building block ribose was found in carbonaceous chondrites.
Klaus Paschek +7 more
doaj +1 more source
PLANETESIMAL DISK MICROLENSING [PDF]
Motivated by debris disk studies, we investigate the gravitational microlensing of background starlight by a planetesimal disk around a foreground star. We use dynamical survival models to construct a plausible example of a planetesimal disk and study its microlensing properties using established ideas of microlensing by small bodies. When a solar-type
Heng, Kevin, Keeton, Charles R.
openaire +2 more sources
Planetesimal Population Synthesis: Pebble Flux-regulated Planetesimal Formation [PDF]
Abstract We propose an expression for a local planetesimal formation rate proportional to the instantaneous radial pebble flux. The result—a radial planetesimal distribution—can be used as an initial condition to study the formation of planetary embryos.
Christian T. Lenz +2 more
openaire +3 more sources
Questions regarding how primordial or pristine the comets of the solar system are have been an ongoing controversy. In this review, we describe comets’ physical evolution from dust and ice grains in the solar nebula to the contemporary small bodies in ...
Jürgen Blum +2 more
doaj +1 more source
Binary formation in planetesimal disks. II. Planetesimals with a mass spectrum [PDF]
Abstract Many massive objects have been found in the outer region of the solar system. How they were formed and evolved has not been well understood, although there have been intensive studies of the accretion process of terrestrial planets. One of the mysteries is the existence of binary planetesimals with near-equal mass components and
Kominami, Junko D., Makino, Junichiro
openaire +2 more sources
During the formation of our solar system, a large number of planetesimals were ejected into interstellar space by gravitational encounters with the planets. Debris disks observations and numerical simulations indicate that many other planetary systems, now known to be quite common, would have undergone a similar dynamical clearing process.
openaire +2 more sources
PLANETESIMAL COMPOSITIONS IN EXOPLANET SYSTEMS [PDF]
We have used recent surveys of the composition of exoplanet host stars to investigate the expected composition of condensed material in planetesimals formed beyond the snow line in the circumstellar nebulae of these systems. Of the major solid forming elements, we find that, as for the Sun, the C and O abundances (and particularly the C/O abundance ...
Johnson, T.V. +3 more
openaire +3 more sources
Four new PLanetesimals Around TYpical and Pre-main seqUence Stars (PLATYPUS) debris discs at 8.8mm [PDF]
Millimetre continuum observations of debris discs can provide insights into the physical and dynamical properties of the unseen planetesimals that these discs host.
Wilner, David J. +27 more
core +1 more source
Multiwavelength Transit Observations of the Candidate Disintegrating Planetesimals Orbiting WD 1145+017 [PDF]
We present multiwavelength, ground-based follow-up photometry of the white dwarf WD 1145+017, which has recently been suggested to be orbited by up to six or more short-period, low-mass, disintegrating planetesimals.
Johnson, John Asher +32 more
core +1 more source
Planetesimal Formation by the Gravitational Instability of Dust Ring Structures
We investigate the gravitational instability (GI) of dust ring structures and the formation of planetesimals by their gravitational collapse. The normalized dispersion relation of a self-gravitating ring structure includes two parameters that are related
Sanemichi Z. Takahashi +2 more
doaj +1 more source

