AMSER Science Reader Monthly

The AMSER Science Reader Monthly aims to provide educators with a useful package of information about a particular topic related to applied math and science by combining freely available articles from popular journals with curriculum, learning objects, and web sites from the AMSER portal. The AMSER Science Reader Monthly is free to use in the classroom and educators are encouraged to contact AMSER with suggestions for upcoming issues or comments and concerns at [email protected].

This month's AMSER Science Reader Monthly topic is Astronomy & Informatics.

When Astronomy Met Computer Science
Article 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 collection.

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 will take interested parties to a rather fascinating set of resources that describes the many ways humans have explored and contemplated space throughout history. 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 leads 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 leads 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 for educators.

1. Cosmic Journey: A History of Scientific Cosmology

Understanding the universe and space in all its complexity has consumed the passions of many people over the millennia. With an interest in bringing material from the world of scientific cosmology to the web-browsing public, the American Institute of Physics and the Center for History of Physics have created this website. The site is divided into two primary areas, titled "Ideas" and "Tools". In the "Ideas" section, visitors can read essays about the development of cosmology from the time of the Greeks all the way up to the present. And moving over to the "Tools" section, visitors can learn about important related events, including the invention of the telescope and the golden era of refractors. The site is rounded out with a collection of links for further reading, such as the "Cosmology 101" site created by NASA and a 1955 National Academy of Sciences briefing on cosmology.

2. Sloan Digital Sky Survey

The Sloan Digital Sky Survey (SDSS) is one of the most ambitious and influential astronomical surveys in history, and "over eight years of operations, it obtained deep, multi-color images covering more than a quarter of the sky and created 3-dimensional maps containing more than 930,000 galaxies and more than 120,000 quasars." The website details the Astrophysical Research Consortium (ARC) mapmaking strategies, timelines, survey progress, and project goals. SDSS data have been released to the scientific community and the general public in annual increments, with the final public data release from SDSS-II occurring in October 2008. Here, visitors can view the many fantastic images collected at the Apache Point Observatory, the site of the SDSS telescopes. While a few of the data links are accessible only to collaborators, the general public can still retrieve SDSS data, an image gallery, educational tools, publications, and much more.

3. Stellarium

With Stellarium, anyone with a computer can view the nighttime sky in three dimensions without stepping outside. Users can view the sky from any location on Earth as well as any time or date, and they can rotate the view to look at specific objects at their leisure. A multitude of configuration tools are available, including zooming in on planets and viewing full-screen images. The website for Stellarium also contains a detailed user's guide and an online forum for asking questions. Also, the labels for constellations, stars, planets, nebulae can be turned off or on. Visitors will also appreciate the fact that there is an exhaustive Wiki here for general consultation. Stellarium can be used with any operating system, including Linux.

4. Nebraska Astronomy Applet Project

The Nebraska Astronomy Applet Project has developed a series of online Introductory Level Astronomy modules that use high-quality simulations to introduce students to important astronomical and astrophysical phenomena. Current modules address the solar system, Earth's seasons, the horizon coordinate system and rotation of the night sky, and the motions of the sun. There are also simulators that demonstrate planetary orbits, the phases of the moon, eclipsing binary stars, and other topics. Each module includes pre- and post-tests, a student guide, and teacher's resources such as pedagogical objectives, a demonstration guide, and assessment materials.

5. Sun-Earth Viewer

The Sun-Earth Media Viewer is a Flash-based interactive tool kit. The viewer allows users to watch real-time NASA satellite images of the Sun and the Earth. The materials are updated on a regular basis, and viewing the transformations of both the Earth and Sun over time is quite amazing. A thumbnail viewer lets visitors explore and compare solar and terrestrial data from a variety of NASA missions and ground-based observatories. In addition, the viewer contains video interviews with scientists and other experts. In the "Interviews" area, teachers and students can learn about auroras, the magnetosphere, solar wind, and the transit of Venus. Visitors can also look at specific clips within each interview for answers to questions like "What is an aurora?" and "Why do we monitor the solar wind?"

6. Lunar and Planetary Science at the National Space Science Data Center

The Lunar & Planetary Science section of the National Space Science Data Center (NSSDC) archives distributes "planetary and lunar data and images obtained from spacecraft missions (both NASA and non-NASA)." Users can find fact sheets, images, and other resources for the nine planets in the solar system as well as for asteroids, the Moon, and comets. Clicking on "Image Resources" under the "Data Services" heading will take visitors to a trove of images. The NASA's Discovery Program link, found in the bottom right corner, describes two new missions, GRAIL and Kepler, along with nine previous missions. The website also provides education resources as well as links to other data archive and service centers.