Citation link:
https://digi.ub.uni-heidelberg.de/diglit/heidhs3695ec4_4/0001
Personal.
l&t. Hamilton, Cal., July 22,1903.
Professor Dr. Max Wolf, Director,
Astrophysical Observatory, Heidelberg.
Dear Sir:-
The number of variable stars now known is about 1200. They
are among the most interesting bodies in the heavens. Their variations
in brightness have been very carefully studied in a large number of cases
by able astronomers. In general, such observations do not require expens-
ive or new telescopes.
The successful study of variable star spectra, on the contrary,
requires powerful and expensive equipment, and the subject is one of
great difficulty. Almost no systematic work on them has been done. If ve
except Algol, o Ceti, 6 Cephei, p Lyrae, Eta Aquilae, Zeta Geminorum, and
A half dozen other stars of the same types, our knowledge is confined
to such facts as that some are of certain spectral types, that others
contain bright hydrogen lines at maximum, etc.
For several years it has been my strong desire to take up the
systematic and extensive study of variable-star spectra. Beginning has
been made on Zeta Geminorum, o Ceti, Nova Aurigae, leva Persei, and a
few ctheo stars; but only as secondary to other programs of work, and
with such minor apparatus as was already available or could quickly be
improvised. Before making extensive plans for researches in this line —
which I should expect to take personal charge of — it would assist me
greatly to receive your expert opinion on the following points:
1. Do you consider that the study of variable-star spectra is an
unusually rich and promising field? Is it desirable that increased re-
sources be made available for promoting this work?
l&t. Hamilton, Cal., July 22,1903.
Professor Dr. Max Wolf, Director,
Astrophysical Observatory, Heidelberg.
Dear Sir:-
The number of variable stars now known is about 1200. They
are among the most interesting bodies in the heavens. Their variations
in brightness have been very carefully studied in a large number of cases
by able astronomers. In general, such observations do not require expens-
ive or new telescopes.
The successful study of variable star spectra, on the contrary,
requires powerful and expensive equipment, and the subject is one of
great difficulty. Almost no systematic work on them has been done. If ve
except Algol, o Ceti, 6 Cephei, p Lyrae, Eta Aquilae, Zeta Geminorum, and
A half dozen other stars of the same types, our knowledge is confined
to such facts as that some are of certain spectral types, that others
contain bright hydrogen lines at maximum, etc.
For several years it has been my strong desire to take up the
systematic and extensive study of variable-star spectra. Beginning has
been made on Zeta Geminorum, o Ceti, Nova Aurigae, leva Persei, and a
few ctheo stars; but only as secondary to other programs of work, and
with such minor apparatus as was already available or could quickly be
improvised. Before making extensive plans for researches in this line —
which I should expect to take personal charge of — it would assist me
greatly to receive your expert opinion on the following points:
1. Do you consider that the study of variable-star spectra is an
unusually rich and promising field? Is it desirable that increased re-
sources be made available for promoting this work?