Related papers: Stardust findings. Implications for panspermia
Whether ice in cold cosmic environments is physically separated from the silicate dust or mixed with individual silicate moieties is not known. However, different grain models give very different compositions and temperatures of grains. The…
It is observed that hypervelocity space dust, which is continuously bombarding the Earth, creates immense momentum flows in the atmosphere. Some of this fast space dust inevitably will interact with the atmospheric system, transferring…
We discuss the properties of several circumstellar debris disk systems imaged with the Hubble Space Telescope's Near Infrared Camera and Multi-Object Spectrometer in a survey of young stars with known far-IR excesses. These dusty disks…
During the first 500 million years of cosmic history, the first stars and galaxies formed, seeding the Universe with heavy elements and eventually reionizing the intergalactic medium. Observations with JWST have uncovered a surprisingly…
Stars are generally spherical, yet their gaseous envelopes often appear non-spherical when ejected near the end of their lives. This quirk is most notable during the planetary nebula phase when these envelopes become ionized. Interactions…
Circumstellar disks of planetary debris are now known or suspected to closely orbit hundreds of white dwarf stars. To date, both data and theory support disks that are entirely contained within the preceding giant stellar radii, and hence…
Contrary to popular belief, the interstellar medium (ISM) is not empty; it is filled with atoms, dust particles, and molecules. Some of these molecules may have been the very building blocks of life that, delivered to Earth via comets and…
We discuss the results of laboratory measurements and theoretical models concerning the aggregation of dust in protoplanetary disks, as the initial step toward planet formation. Small particles easily stick when they collide and form…
We have observed the continuum emission of the interacting galaxy NGC4631 at 0.87 and 1.23mm using the Heinrich-Hertz-Telescope on Mt. Graham and the IRAM 30-m telescope on Pico Veleta. We have obtained fully sampled maps which cover the…
Using the hydrodynamic code ZEUS, we perform 2D simulations to determine the fate of the gas ejected by massive stars within super star clusters. It turns out that the outcome depends mainly on the mass and radius of the cluster. In the…
Wolf-Rayet (WR) stars are luminous massive blue stars thought to be immediate precursors to the supernova terminating their brief lives. The existence of dust shells around such stars has been enigmatic since their discovery some 30 years…
We investigate Galactic bulge planetary nebulae without emission-line central stars for which peculiar infrared spectra have been obtained with the Spitzer Space Telescope, including the simultaneous signs of oxygen and carbon based dust.…
Recent Spitzer observations of the globular cluster M15 detected dust associated with its intracluster medium. Surprisingly, these observations imply that the dust must be very short-lived compared to the time since the last Galactic plane…
The emergence of habitable conditions on the early Earth and on rocky exoplanets requires persistent energy sources that can drive both prebiotic chemistry and climate warming under magnetically active young G to M stars. To quantify the…
We present the discovery of debris systems around three solar mass stars based upon observations performed with the Spitzer Space Telescope as part of a Legacy Science Program, ``the Formation and Evolution of Planetary Systems'' (FEPS). We…
We have carried out a multiwavelength observational campaign demonstrating some of the remarkable properties of the infrared-bright variable star BP Psc. Surrounded by a compact dusty, gaseous disk, this little-studied late-G (or early-K)…
The first steps toward planet formation involve the coagulation of small microscopic grains into larger and larger pebbles and rocks in gas-rich disks around young stars and brown dwarfs. Observations in the sub-millimeter can trace…
Stars and planets form, live, and evolve in unison. Throughout the life of a star, dusty circumstellar discs and stellar outflows influence the further evolution of both the star(s) and their orbiting planet(s). Planet-forming discs, winds…
We report far-infrared and submillimeter observations of Supernova 1987A, the star that exploded on February 23, 1987 in the Large Magellanic Cloud, a galaxy located 160,000 lightyears away. The observations reveal the presence of a…
Dust is a key component of the Universe, especially regarding galaxies evolution, playing an essential role for both the physics and chemistry of the interstellar medium. In this paper, we give a brief review of interstellar dust. We…