Potassium tells a tale
Article Abstract:
A new and accurate measurement of the isotopic abundance of potassium in samples from the different parts of the world has been reported by Munir Humayun and Robert Clayton. The composition of the inner rocky planets does not match with that of original rocky components of the nebula. Earth, Mars, Venus, and the Moon have very little potassium. This had made measurement of potassium very difficult. Humayun and Clayton have attained a precision of plus or minus 0.5 parts per thousand in measuring the 41K/39K ratio which is considerably better than the previous results.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1995
User Contributions:
Comment about this article or add new information about this topic:
Vestiges of a beginning?
Article Abstract:
New isotopic evidence indicates that the Earth's crust separated from the mantle between 4.44 and 4.54 billion years ago. Charles L. Harper and Stein B. Jacobsen analyzed the isotopic content of crustal samples from Isua, Greenland and concluded that the crust formed earlier than four billion years ago as most geologists believe. However, Harper and Jacobsen's findings will have to be duplicated before they can be generally accepted.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1992
User Contributions:
Comment about this article or add new information about this topic:
Why can't planets be like stars?
Article Abstract:
The discovery of more than 100 planets orbiting stars other than the Sun has brought the question of planetary origin and evolution into focus. Stars are relatively uniform in composition and differ mostly in mass unlike stars.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 2004
User Contributions:
Comment about this article or add new information about this topic:
- Abstracts: PET for dementia drug test. Bias alleged in Japanese university awards. Earthquake prediction 'likely to grow' after new review
- Abstracts: Resolution of the circumstellar gas around the Be star Psi Persei. A large-scale, interstellar Faraday-rotation feature of unknown origin
- Abstracts: Motor learning in a recurrent network model based on the vestibulo-ocular reflex. Stochastic resonance without tuning
- Abstracts: Possible blindsight in infants lacking one cerebral hemisphere. A forkhead-domain gene is mutated in a severe speech and language disorder
- Abstracts: Control of RNase E-mediated RNA degradation by 5'-terminal base pairing in E. coli. The bacterial enzyme RppH triggers messenger RNA degradation by 5' pyrophosphate removal