When Astronomy Met Computer Science
by Preston Lerner
Synopsis and resource annotations by Max Grinnell
In the past, astronomers struggled to analyze all the data they collected each
time they looked at the night sky. However, with the arrival of new telescopes
and computers, today's sky surveys can catalog billions of astronomical
objects. This article by Preston Lerner originally appeared in the April 2011
issue of Discover
Magazine, and it takes a close look at the ways in which computer science
and informatics have informed major developments in astronomical data
The piece begins by talking about the work of researcher and professor Kirk
Borne, who was employed at NASA's National Space Science Data Center in
Greenbelt, Maryland. Another astronomer asked if the Center could archive a
terabyte of data that had been collected by a prominent sky survey. After
talking with his boss, who was a bit incredulous, he realized that they
"needed to do something not only to make all that data available to scientists
but also to enable scientific discovery from all that information."
The piece moves on to discuss how, over the past eleven years, the Sloan
Digital Sky Survey at the Apache Point Observatory in New Mexico has imaged
over one-third of the night sky. The computational analysis from this
tremendous data set has uncovered evidence of little-known astronomical
objects, and it has also mapped out the three-dimensional structure of the
local universe. More sky surveys are continuing across the world, and they
include the work done by the Large Synoptic Survey Telescope in Chile. The
camera inside this instrument will be able to capture an area 49 times as
large as the moon in each 15-second exposure when it is operational in 2019.
While all of this data could prove quite useful, there remains one possible
problem: data deluge. As Professor George Djorgovski, an astronomy professor
at CalTech commented, "For the first time in history, we cannot examine all of
our data. The challenge is to develop a new scientific methodology for the
21st century." The key component of such a methodology will be the
data-crunching technique known as informatics, which is the use of computers
to extract meaning from raw data too complex for the human brain to analyze.
By developing astroinformatics, computers can assist astronomers by doing what
they have done for centuries in a greatly reduced timeframe. These algorithms
can scour terabytes of data in seconds, highlight patterns and anomalies,
visualize key information, and even "learn" on the job. For example,
astroinformatics will help astronomers search more methodically for extreme or
"unusual" objects, such as high-redshift quasars, which are extremely
distant and luminous objects powered by supermassive black holes.
Additionally, astronomers are now using algorithms to look over some of these
image data sets to estimate an object's distance. The piece concludes by
offering links to some exciting astronomy projects, such as the Galaxy Zoo,
which uses volunteers to help classify images from the Sloan Digital Sky
Survey on their home computers.
Found below is a list of useful resources that will illuminate and enhance
understanding of the topics found within this article.
The first link
take interested parties to a rather fascinating set of resources that
describes the many ways humans have explored and contemplated space throughout
The second link
leads to the homepage of the Sloan Digital Sky Survey. Here visitors can view
tutorials on using their data sets and also find out more about their
tremendous digital image collections.
The third link
to the Stellarium website, which is an open-source application that can used
to view the sky from any location on Earth.
Moving along, the fourth link
leads to the Nebraska Astronomy
Applet Project site, which features great resources for educators, including
simulators that demonstrate planetary orbits and the phases of the moon.
The fifth link
whisks users away to the Sun-Earth Viewer site, which lets users watch
real-time NASA satellite images of the Sun and the Earth.
The final link
visitors to the Lunar and Planetary Science section of the National Space
Science Data Center. Here visitors can find fact sheets, an image gallery, and
other resources for the planets in the solar system, along with lesson plans