Selected Astronomical Catalogues
and Online Data Services
-- and a Few Other Interesting Sites
As usual, I've had correspondence with Steve Gottlieb, Gary Kronk, Yann
Pothier, Courtney Seligman, Brian Skiff, Sue French, and Wolfgang Steinicke on
several interesting objects, and I've reconsidered a few of the puzzling cases
myself. There is more detail on these in the
NGC/IC introductory file available here and in the various Notes
My re-examination of the Galactic open clusters is continuing, and has become
a part of a second sweep through the NGC (I have finished the NGC clusters)
and IC in order to collect Gaia DR1 positions for as many objects as possible.
The Gaia data have very small errors, 1.0 milliarcseconds or better claimed
for stellar images, and surprisingly close to that for galaxy nuclei.
However, as with most position data collected "automatically," those from Gaia
sometimes refer not to the galaxy nuclei, but to superposed stars (e.g. NGC
354, NGC 380, NGC 561), "knots" (emission regions, clusters, etc.) in the
galaxies (e.g. NGC 317), or are simply pulled off the nucleus by other bright
features in the galaxy's image (e.g. NGC 499). So, each case must be
considered individually, one by one by one ...
Courtney Seligman's comment to me about Pan-STARRS images last fall led me
to look into the positions from DR1. Coincidentally, those became available
at VizieR at about the same time. They are apparently tied very tightly to
the Gaia DR1 astrometric reference frame as I have found it unusual to see
disagreements between them of more than about 20-30 milliarcseconds. They
still need to be checked against other positions for the same object, but they
are clearly another excellent source of positions on the sky.
Finally, I have had a couple of requests for a "clean" list of the NGC and IC
objects. This will not include the superposed and nearby stars or the
"companion" objects. I am working on this list, and hope to have it ready for
the next update of these files.
Here are some notes from previous releases of these files.
The Gaia DR1 data have a nominal epoch of 2015.0 and are largely without
proper motions (proper motions are calculated only for the ~2.5 million
objects in the Tycho and Hipparcos lists). Proper motions will be added in
later data releases along with calculated J2000 positions. The recent epoch,
of course, is not a problem for galaxies, but for the superposed stars, or for
Galactic objects (e.g. asterisms, foreground stars, planetary nebulae), simply
precessing the positions to 2000.0 will generally not yeild positions as
accurate at the "standard" J2000.0 equinox and epoch as at the nominal epoch.
Brian Skiff and I have now selected accurate positions for all of the NGC and
IC objects. These are in the current versions of my
NGC/IC position and notes files available
here, as are positions and notes for about 130 non-stellar objects
(or objects thought to be non-stellar) that were known before the NGC was
published, but not included in it.
There are still many checks to be done, and a full comparison with the
original positions also remains. Finally, I am committed to providing data
(particularly magnitudes and diameters) for all of the objects, too. So,
check back now and then for updates. I'll announce them on the "amastro"
mailing list as they become available, so you could check there as well.
The Revival of the NGC/IC Project
The NGC/IC Project web site
disappeared from the web early in 2017. Fortunately, taking a cue from the
constellation Phoenix, it is arising from the ashes of its former incarnation,
this time guided by a team from
The Astronomy Connection in the San
Francisco Bay area. At the moment, the old site is again online pretty much
as it existed earlier. It is not yet be fully functional as I write, but its
main features are present. Eventually, a clean new site will be built around
this humble revival. Please get in touch with
John Pierce, or
if you'd like more information. I'm pleased to say that we are also
benefitting from advice and assistance from several others including Sue
French, Brian Skiff, Andrew Pierce, and Wolfgang Steinicke.
Extragalactic Catalogues Maintained by Harold G. Corwin, Jr.
The copies of
The Third Reference Catalogue of Bright
Galaxies, by G. de Vaucouleurs, A. de Vaucouleurs,
H.G. Corwin, R.J. Buta, G. Paturel, and P. Fouqué
A Catalogue of Rich Clusters of Galaxies
, by G.O. Abell, H.G. Corwin, and R.P. Olowin,
A Southern Galaxy Catalogue
by H.G. Corwin, A. de Vaucouleurs, and G. de Vaucouleurs,
found here are corrected versions of the published catalogues. Though all
three are available as printed and bound books, the electronic versions are
preferred for reference as all known errata occuring in the printed versions
have been corrected. Please let me know if you find any further errors.
Brief explanations of the data are also available electronically; the full
introductions with figures, tables, and references are only available in the
I am very saddened to note the death on 5 August 2017 of Professor Ronald P.
Olowin, my valued colleague and friend, and co-author of the southern Abell
Catalogue. Ron had been on the faculty at St. Mary's College in Moraga,
California for 30 years. Among his many accomplishments at St. Mary's, he
introduced astronomy to the curriculum, and spearheaded the building of the
Geissberger Observatory on the College campus. Ron was 72. An obituary may
be found at
the St. Mary's College web site.
A final version (1.4.3) of
A South-Equatorial Galaxy Catalogue
by Harold G. Corwin, Jr. and Brian A. Skiff.
is also available. This has accurate positions, diameters, position angles,
and de Vaucouleurs revised Hubble-Sandage (VRHS) types for 3333 single or
multiple galaxies in the south-equatorial declination zones between +3 degrees
and -21 degrees. The data were gleaned from POSS1 103a-O copy plates, then
checked against the UKST IIIa-J portion of the DSS. The corrected position
angles and VRHS types are published here in full for the first time. Notes on
the individual objects are also available. SEGC provides a finding list for
galaxies generally larger than about 1.8 arcmin at the 25.0 B-mag arcsec^-2 in
the south-equatorial zone between the southern limit of the CGCG and UGC, and
the northern limit of ESO-B, ESO-LV, and SGC. It provides a somewhat
shallower coverage of this part of the sky than MCG.
All of these catalogues are freely accessible; I and my coauthors ask only
a reference and/or an acknowledgment if you use data from them.
Links to Useful Astronomical Web Sites
Most of these Web sites are devoted to astronomical cataloguing and data
NED -- NASA/IPAC
Virtual Observatory on the Web
The NASA Astrophysics
MAST -- The Space Telescope Science
Institute HST Data Archive
The Canadian Astronomy
The ESO/ST-ECF Science Archive
The NGC/IC Project
Steinicke's Home Page, with links to his historical work
on the observations leading to the Dreyer's NGC and IC
Steinicke's biographical information for the NGC/IC
Celestial Atlas featuring images and notes for many
celestial objects, including the
NGC and IC objects
Seligman's list of refrences and links to NGC/IC observer biographies
and published papers
The Webb Deep Sky Society
Links to Music Web Sites
The Source for Classical Music is a clearing house for
virtually all of the distributors of recorded classical music in the
USA. I use their service frequently as it is fast and reliable. If
there are problems (I've had just two in the past decade), their
customer service reps will fix them quickly. They do downloads as
well as physical media, and have begun a streaming service as well.
They also have agreements with many record companies to make deleted
issues available as on-demand CD-Rs.
Fanfare -- The Magazine for
Serious Record Collectors. If you have any interest at all
in listening to classical or jazz recordings, this magazine is for
you. Published every two months, it is packed with reviews of most
of the classical music recordings released in the US. The reviewers
write knowledgeable and interesting reviews, and there is an on-line
archive of the magazine's reviews and feature articles since it began
publication in 1977.
Brian Society promotes the music of the 20th century English
composer and critic Havergal Brian. I must confess that I find his
orchestral music fascinating and frustrating all at once.
Tonally-based and superbly orchestrated, his music is nevertheless
among the more difficult that I have tried to get a grip on. Brian's
works overflow with ideas, and often burst through the usual formal
constraints of symphonic music. The disconcerting result is that I
am often lost among the trees while trying to make out the overall
patterns of his wonderful forests of sound.
The Ralph Vaughan Williams
Society. I had seen this Society mentioned in several of the
music magazines I subscribe to, and had wondered at its intent.
Vaughan Williams, after all, is -- along with Sir Edward Elgar --
the composer most responsible for the renaissance of English music in
the first half of the 20th century. Many of his works are are among
the greatest of that century, and are recorded frequently, so why
does this Society exist? As it happens, Vaughan Williams's
well-known music is just a portion of his considerable output over
his long composing career (the 1890s until his death in 1958). The
RVW Society promotes performances and recordings of Vaughan
Williams's lesser-known music -- some never performed before -- and
has issued thirty (so far!) recordings on its own "Albion" label.
"Vaughan Williams," by the way is an unhyphenated double last name;
others like it (e.g. "Maxwell Davies") are relatively common in Great
The Buffalo Philharmonic Orchestra
is our orchestra. While perhaps not quite in the top rank of
orchestras in the world, the BPO is very close, and we are lucky to
be living in a city that supports them. They have many recordings
available, most with their long-time conductor JoAnn Falletta, that
demonstrate their versatility. In my opinion, almost all of the
recordings are worth adding to your collection. Buying the
recordings directly from the
BPO makes a contribution to the orchestra as well as
providing you with a fine CD.
Links to Railroading Web Sites
Amtrak -- the National Railroad
Passenger Corporation provides intercity passenger train
service in the US. We are fortunate to have an Amtrak station within
a few miles of our home, so we travel by train when we can.
the Rail Passengers Association
(formerly NARP -- the National Association of Railroad
Passengers) is a primary voice in Washington, DC speaking on behalf
of train and rail transit passengers. NARP has some considerable
clout in helping to keep Amtrak going.
ESPA -- the
Empire State Passengers Association has moved its main web
presence to Facebook. Just as NARP is an organization devoted to
promoting rail travel across the United States, so is ESPA "working
for better rail passenger service and public transportation in New
York State." In principle, ESPA promotes transportation initiatives
across the entire state, but it seems to be primarily focused on
Upstate issues affecting passenger travel outside the New York City
Southern Pacific Historical &
Technical Society is dedicated to preserving and
disseminating the historical record of the Southern Pacific Railroad
and its affiliates. The Southern Pacific was "my" childhood railroad
in California, and I renewed my attachment to it during my twenty
years there between 1991 and 2011. SPH&TS publishes "SP Trainline"
four times a year. Yes, the magazine is a nostalgia trip for me,
with a strong focus on the railroad itself. But the "Espee" is also
an important element in the history of the western and southwestern
United States. "Trainline" often provides that broader context.
Model Railroading is a glimpse
inside the mind of an atypical model railroader. I call myself
"atypical" because I have no layout where I can actually run my
trains, and no large space where I can even contemplate building such
a layout. Nevertheless, I have a lot of rolling stock, almost all
modeled from Southern Pacific prototypes (see above) or from Amtrak
prototypes (also see above). Once in a while, I will report on my
model railroading activity in this space. At the moment, this
directory has before and after photos of an HO model of a single
Amtrak passenger car that I've recently modified, as well as a link
to a photo of the prototype.
Note that I have closed my gmail account. Please use the above email address
The previous version of this site was made possible by the
and Analysis Center, which is operated by the
Laboratory and the
California Institute of Technology, under
contract with the National Aeronautics
and Space Administration. I am pleased to acknowledge their
support prior to my retirement in July 2011.
that earlier version of this site which will serve as an archival
snapshot of the catalogues as they existed when I loaded them into NED.
I use GoDaddy for hosting and
domain services. They offer far more than I need, but what I do need from
them is easy to use and reliable.
Latest update: 28 January 2018