The astrophysics group maintains a small group of Linux
for beginning graduate and undergraduate students. These
computers are in room 2169 FRH. Students who want an
these machines should see Aaron Barth.
A few general notes: please don't bring food or beverages into
computer room. Please try not to touch the flat-panel LCD
screens- they will last pretty much forever if we take good care
them, but once they get scratched there's no way to fix
Don't lock the screen on these machines if you're going to be
the computer room for more than a short while. Instead
out so that someone else can use the system.
We have 2 HP laser printers for the astrophysics group, one
white and one color. The black & white printer is set
Basic Linux/Unix skills.
If you're a beginner, there are various web sites that give
introductory lessons on Linux commands, text editing,
site that has a lot of useful information.
The Scientific Linux distribution includes a lot of very useful
a text editor
- vi, a text editor
- LaTeX, a
processing system optimized for mathematical and scientific
- The gcc and
- Python, along with
various useful libraries such as numpy and matplotlib.
- OpenOffice: an
suite including word processing and spreadsheets, able to
Office file formats reasonably well
- Web browsers: mozilla and firefox
reader (from the command line, type acroread)
A note about shells: the "shell" is the command language
that interprets what you type at a terminal prompt. The
popular shells are bash
somewhat different syntax for scripting and for things like
environment variables. Bash is the default shell for linux
days, and most linux manuals will use bash syntax.
However, a lot
of astronomical software that's been around for years has
written using tcsh syntax. You can use either one and it's
a matter of preference. If you're reading the
documentation for a
program and it tells you to issue a command like "setenv X y",
tcsh command. The equivalent bash command would be "X=y;
X". Every time you start up a new terminal
your shell will read either the .bashrc or the .cshrc file (if
using bash or tcsh, respectively) in your home directory.
files are where you put definitions for your executable search
aliases, and things like that which you want to be read in every
you bring up a terminal window.
Astronomical software installed
student computers includes:
Other useful computing
Web resources for astronomy:
- IRAF: a
reduction and analysis package distributed by NOAO.
IRAF has horribly
cumbersome syntax, crashes easily, and it's a pretty
to script. However, it includes a huge variety of data
routines that are often the easiest and most efficient way
certain tasks, and some data reduction packages for the
Telescope or other observatories are written in IRAF.
most of which are pretty old, but IRAF hasn't changed
much since they were written.
is a Python-based front-end for IRAF that's designed to be
user-friendly than the standard IRAF cl interface.
Once your iraf
directories are set up and working, you can just type
"pyraf" at the
linux prompt to start this up. (See the iraf setup
above for additional important notes on using pyraf.)
is an image-display program that works either as a
stand-alone or as a
display tool for IRAF/PyRAF.
This is an
image-processing environment and programming language.
It's a very efficient language for astronomical data
analysis and very easy to learn.
is a graphing/plotting program that can read in data from
tables, perform mathematical manipulations, and generate
publication-quality plots. The sm homepage has a
and a lot of
information about using the program.
- The arXiv
e-print server (known to astronomers as "astro-ph").
upload electronic preprints, and each day a list of new
appears on the arXiv web site. You can sign up for a
of new abstracts too. It's good to get in the
habit of at
least skimming through the list of new abstracts each
- The NASA
Data System (ADS). This is a web index of the
entire published astronomical literature. You can
author name, title or abstract content, or object names and
generate a list of publications that match your query,
to electronically published articles or scanned versions of
articles from the pre-electronic era. There are a lot
things here, like the ability to search for papers that were
also read by people who read a given paper.
- The NASA/IPAC
Extragalactic Database (NED). A searchable index
extragalactic objects including galaxies, quasars, galaxy
etc. Users can search by object name or
- The SIMBAD
database. A database of Galactic objects, useful for
properties of a particular star, or for selecting a list of
matching known criteria.
- The MAST archive
Space Telescope Science Institute. This is an
archive that includes the Hubble Space Telescope and many
- The Sloan Digital Sky
Users can search for objects matching a list of criteria
queries and download images and spectra.
- The HEASARC
archive. A data archive of X-ray missions.
of the Day. A nice resource for pretty pictures,
a good place to submit a picture from your own research if
something you want to show off to the public.
- American Astronomical
Links to membership information, meetings, grants, and more.
the Pacific. Links to membership information,
and an online store of astronomical stuff.
Meetings List. A list of upcoming conferences.
- The AAS
Job Register. An online listing of job offerings
astronomy, updated monthly.