W. M. Keck Cosmochemistry Laboratory - Related Research

Research into the Origin of the Solar System

We use the Cameca ims 1280 and associated equipment to investigate the origin of the solar system. The research can be thought of as consisting of three basic types of investigations:
  1. Studies of the raw materials that were the building blocks for the solar system, including presolar grains from meteorites, interplanetary dust particles, and comet samples returned by the Stardust mission.

  2. Studies of the timing of events during the formation of the solar system. Chronology is investigated through studies of short-lived radionuclides.

  3. Studies of early solar system processes, which we investigate through measurements of chemical compositions, trace-element abundances, isotopic fractionations, and the unique variations exhibited by oxygen isotopes.

  Here is a Listing of peer-reviewed publications resulting from research carried out with the ion microprobe.

Many of our studies have been highlighted on the Planetary Science Research Discoveries educational website. These articles include:
  • Ion Microprobe -- An introduction to the innards and applications of the ion microprobe.

  • Chondritic Asteroids–When Did Aqueous Alteration Happen? -- New dates determined for aqueous alteration on chondritic parent bodies, based on a new mineral standard, have big implications on the timing and location of accretion.

  • Chronicles of a Chondrule's Travels -- Isotopic measurements of a chondrule in a Comet Wild 2 grain tell the story of outward migration of solar nebula solids, helping to set the formation age of Jupiter.

  • Leftovers from Ancient Lunar Impactors -- A systematic search for meteorite fragments in ancient regolith breccias confirms chondritic impactors on the Moon.

  • Little Chondrules and Giant Impacts -- Chondrules in metal-rich meteorites formed a couple of million years after most other chondrules, possibly by impact between moon-sized or larger objects.

  • Making Sense of Droplets Inside Droplets -- The vexing presence of chondrules inside supposedly older calcium-aluminum-rich inclusions (CAIs) in chondrites makes sense if the CAIs were remelted.

  • New View of Gas and Dust in the Solar Nebula -- The current view holds that gas and dust in the solar nebula began with the same oxygen isotopic composition, then changed by processes in the nebula. A new view suggests that dust and gas had vastly different mixtures of oxygen isotopes in the first place.

  • Primeval Water in the Earth -- Hydrogen isotopes in lavas derived from the deep mantle suggest the presence of a component inside the Earth that came directly from the primordial solar nebula.

  • Searching for Ancient Solar System Materials on the Moon, Earth, and Mars -- The early history of the Solar System is recorded by meteorites falling now, but also by those that fell hundreds of millions to billions of years ago, preserved in lunar samples, sedimentary layers on Earth, and even sitting on the surface of Mars.

21 April 2017