Skip to search formSkip to main contentSkip to account menu

High Proper-Motion Stars in the Vicinity of Sagittarius A*: Evidence for a Supermassive Black Hole at the Center of Our Galaxy

Over a 2 year period we have conducted a diffraction-limited imaging study at 2.2 μm of the inner 6'' × 6'' of the central stellar cluster of the Galaxy using the W. M. Keck 10 m telescope. The…
View on IOP Publishing (opens in a new tab)

ECHOES OF A DECAYING PLANETARY SYSTEM: THE GASEOUS AND DUSTY DISKS SURROUNDING THREE WHITE DWARFS

We have performed a comprehensive ground-based observational program aimed at characterizing the circumstellar material orbiting three single white dwarf stars previously known to possess gaseous…
View on IOP Publishing (opens in a new tab)

ANCIENT PLANETARY SYSTEMS ARE ORBITING A LARGE FRACTION OF WHITE DWARF STARS

Infrared studies have revealed debris likely related to planet formation in orbit around ∼30% of youthful, intermediate mass, main-sequence stars. We present evidence, based on atmospheric pollution…
View on IOP Publishing (opens in a new tab)

AN ALUMINUM/CALCIUM-RICH, IRON-POOR, WHITE DWARF STAR: EVIDENCE FOR AN EXTRASOLAR PLANETARY LITHOSPHERE?

The presence of elements heavier than helium in white dwarf atmospheres is often a signpost for the existence of rocky objects that currently or previously orbited these stars. We have measured the…
View on IOP Publishing (opens in a new tab)

CHEMICAL ABUNDANCES IN THE EXTERNALLY POLLUTED WHITE DWARF GD 40: EVIDENCE OF A ROCKY EXTRASOLAR MINOR PLANET

We present Keck/High Resolution Echelle Spectrometer data with model atmosphere analysis of the helium-dominated polluted white dwarf GD 40, in which we measure atmospheric abundances relative to…
View on IOP Publishing (opens in a new tab)

ELEMENTAL COMPOSITIONS OF TWO EXTRASOLAR ROCKY PLANETESIMALS

We report Keck/HIRES and Hubble Space Telescope/COS spectroscopic studies of extrasolar rocky planetesimals accreted onto two hydrogen atmosphere white dwarfs, G29-38 and GD 133. In G29-38, eight…
View on IOP Publishing (opens in a new tab)

Oxygen fugacities of extrasolar rocks: Evidence for an Earth-like geochemistry of exoplanets

TLDR
The elemental abundances observed in six white dwarfs polluted by the accretion of rocky bodies are exploited to determine the fraction of oxidized iron in those extrasolar rocky bodies and therefore their oxygen fugacities, suggesting that at least some rocky exoplanets are geophysically and geochemically similar to Earth.
View on Science (opens in a new tab)

POSSIBLE SIGNS OF WATER AND DIFFERENTIATION IN A ROCKY EXOPLANETARY BODY

Spitzer observations reveal the presence of warm debris from a tidally destroyed rocky and possibly icy planetary body orbiting the white dwarf GD 61. Ultraviolet and optical spectroscopy of the…
View on IOP Publishing (opens in a new tab)

The Chemical Composition of an Extrasolar Kuiper-Belt-Object

The Kuiper Belt of our solar system is a source of short-period comets that may have delivered water and other volatiles to Earth and the other terrestrial planets. However, the distribution of water…
View on IOP Publishing (opens in a new tab)

Hydrocarbon poisonings.

View on PubMed (opens in a new tab)
By clicking accept or continuing to use the site, you agree to the terms outlined in our Privacy Policy (opens in a new tab), Terms of Service (opens in a new tab), and Dataset License (opens in a new tab)