Home Page for Charles R. Cowley



Click for ppt of Meteorites as Stars

Click for ppt of GCE corrected [El/H] vs Tc

Click for 79 plots (BD18)

Click for 79 new plots with GCE corrections

For a new view of Galactic Chemical Evolution: Try This

Click for Condensation Temperature Dependence of Precision Differential Abundances

A New Line Identification List for Procyon, also measurements from AN, 341, 125, 2020, and pdf of paper.

Sirius: Identifications; supplement to ApJ, 826, 158, 2016

The History of Matter is a short textbook for a course I gave shortly before I retired in 2007. The astronomy is a little bit dated, but the physical and geological principles may still be of interest.

10 Aql: Wavelengths and identifications

Wavelength measurements for the B2 IVp star HD 133518

Online data for PDS2

HD 101412: A sharp-lined Herbig Ae star whose abundances differ significantly from solar.

Check this essay on Pluto as a planet

MMB Click here

The Super-Rich Mercury Star HD 65949

HR 710 (HD 15144): Wavelengths, identifications, and equivalent widths.

Click for wavelength measurements in HD 101065, now from 3047A to 1.04 microns.

A wavelength identification list for the HgMn star HR 7143 (HD 175640)

Take this link for PowerPoint presentations on Atomic (and a little) Molecular Data and Lines as Continuous Opacity for IAU Symposium 210. The table of ionization energies was prepared for IAU Symposium 210.

Link here for resume of recent work on Balmer lines (cf. Astron. Ap., 387, 595, 2002).

The sun and similar stars have compositions often called the standard abundance distribution, or SAD .

roAp Stars Have Abnormal Atmospheres

Click for an illustration of H-alpha profiles.

Check out the essay on The Grand Canyon and the Moon.

Check here for Serenity

Robert Louis Stevenson's Where Go the Boats?


Visitors to this page since 20 September 1999:


I am an emeritus professor of astronomy at the University of Michigan. My specialty is analytical stellar spectroscopy, or stellar abundances. I am generally interested in abundances of physical systems throughout the universe.

I am also the grandfather of Shelby Jane Cowley. Click for an image of Shelby and her dad taken in the spring of 2001.


Errata for the textbook An Introduction to Cosmochemistry is available here.

We are also maintaining an electronic version of the Bidelman HR 465 line identification list (Pub. Univ. Mich. Vol. 12, No. 3, 1995) in the anonymous ftp space pub/get/cowley/hr465. Documentation is in the file read.me. A new study of Dy III by Spector, Sugar, and Wyart has enabled us to make additional identifications, not yet incorporated in the posted list. An older study of HR 4816 = HD 110066 is also available.


We finished work on the spectrum of the bizarre object known as Przybylski's star in late 1999. The new study superceedes the preliminary study by Cowley and Mathys. The reference is Monthly Notices, 317, 299 (2000).

We have prepared a WebPage on Przybylski and his famous star. In addition to the recent results including line abundances and identification lists, you will find a picture of the man a key to the pronunciation of his name.

For many years, we thought Przybylski's star was unique. Recently, after a detailed study, we decided we agreed with a small number of colleagues who said it was extreme, but a member of a reasonably well understood class. Over the last six months, we have learned of significant peculiarities in the spectra of members of this class of rapidly oscillating Ap stars (roAp's). Contrary to a long held view, the atmospheres of these stars cannot be normal. Evidence for this is in a short paper in Astronomy and Astrophysics, Vol. 367 (No. 3), pp. 939-942 (2001). We also put it up on astro-ph. Click here for an illustration of the CWA.

Donald Bord and I have continued our work on abundances of trace elemental species in the solar atmosphere. Recent work, including collaboration with James Lawler, and Christopher Sneden has been on lutetium, holmium, and terbium. Several of the Tb II lines are influenced by high members of the Balmer series. This provoked a study to see how realistically we could make calculations of Balmer lines in general.


Check out some of the material below including links to a web text for solar system astronomy. In the spring of 1999, our class did an exercise using a restricted three-body program that opened my eyes to some possibilities for the capture of satellites. I don't think this would be new to experts in this field, but you might get a kick out of what I call restricted three-body capture.


A CV is located here.


Free Turoring is available for all 100-level courses by the Student Astronomical Society. The instruction is carried out by advanced undergraduate astronomy majors.


We once offered a 4 credit hour course in Modern Planetary Astronomy (Astron 115) which was approved as QR/2. It was a 4-hour credit introductory course, with the same prerequisites as Astronomy 101/111 and 102/112. Since I am now retired, the course is no longer available in the old form. However, some links to the materials are still maintained as they may be of general interest.

The complete web text is available online and you may peruse it. A newer edition, courtesy of Barbara Eckstein is essentially complete. Links to these files have been taken off line, but if you are interested in them, email cowley@umich.edu, and I should be able to make them available to you. An older, more printer-friendly text is divided into three sections. You may click on 1,2, or 3. You can also examine the 10 laboratory exercises. There will be no assigned text book.

My approach to planetary astronomy was to emphasize similarities of materials and processes at work on the planets AND the earth, and how these processes write the history of these bodies in their chemistry and mineralogy. The course presented the earth as a planet, and the planets and some of their satellites as bodies that have similarities as well as differences with the earth. I also emphasized the techniques and tools used in the exploration of the solar system, drawn from physics, chemistry, geology. The last few lectures covered modern developments in molecular- and biochemistry and the ever-relevant question of life on other worlds.