Digital Universe: The Data Behind the Dazzle
by AMNH on
There’s a method to the sparkle in the Hayden Planetarium Dome. Each of the approximately 4000 bright specks projected onto the Dome to visualize the night sky is backed by hard data collected by NASA and dozens of other organizations around the globe.
At approximately 20 GB, data drives the Digital Universe, a scientifically accurate three-dimensional atlas of the cosmos developed by the Hayden Planetarium at the American Museum of Natural History. The atlas, which is used in about 200 planetariums and venues worldwide, is also available in a scaled-down version for home computers (download it for free here to begin your own cosmic adventure).
Brian Abbott, the Assistant Director of the Hayden Planetarium, helped develop the Digital Universe starting 14 years ago. Abbott, who gives live guided tours of the Digital Universe for the Museum’s Astronomy Live series and continues to crunch data that keeps the universe-sized map as current as the latest research, recently spoke to us about the Dome, the data, and his favorite parts of the job.
What’s the idea behind Digital Universe atlas?
We want to show people where they are in the universe. Astrophysicists use numbers and charts to understand our place in the universe; we want to take it a step further and give people a visceral experience of being there. The Digital Universe allows us to convert raw data from astrophysicists and navigate through the cosmos spatially. For some, “flying” through the atlas in the planetarium Dome is a profound experience; I’ve seen people walk out in tears.
What sort of things can we see while “flying” through the Digital Universe?
With the Digital Universe, we are primarily interested in looking at the distribution of objects around the Sun. They tell an incredible story. We can see where all the known planets exist outside our solar system, how far our radio signals have traveled, as well as the largest galaxy structures in the universe, called superclusters.
What is your role at the Hayden Planetarium?
I oversee many activities in the Office of the Director, including the construction of the Digital Universe atlas. This involves acquiring new data from astrophysicists, writing software to process those data, and I occasionally have the privilege of guiding audiences through the Digital Universe during the Astronomy Live public programs at the Museum. Flying an audience through the atlas and experiencing the universe through their eyes has to be one of my favorite parts of the job.
What does it take to update the “universe”?
All of the data in the Digital Universe come from a variety of astronomical catalogs . One of the most accurate star catalogs is the Hipparcos Catalog. In the full catalog, each star has over 200 different fields, describing everything from the star’s color and luminosity to its proper motion—its physical motion translated onto the sky. This is a screen shot of what the catalog looks like when I receive it.
To plot a star in 3D space, I am primarily concerned with the three highlighted columns. The two circled in red are the Right Ascension and Declination, analogous to Earth’s longitude and latitude; in the sky, these numbers uniquely identify every point on the “celestial sphere.” The third column, circled in blue, is the parallax, which is a measure of the star’s apparent shift in position due to Earth’s orbit around the Sun. Beyond these three numbers, we also need the star’s brightness, color, and other metadata in order to represent it correctly in the atlas.
Have you always been interested in astronomy and astrophysics?
In high school, I was on a path to become an artist. Then, in 1986, Halley’s Comet visited the inner solar system as it does every 76 years. The more I learned about it, the more I wanted to see this once-in-a-lifetime event. I began to study the night sky. Soon, I found myself more enthralled with astronomy and less interested in art. I switched out of the art program and into math and physics courses, eventually gaining degrees in Astronomy & Astrophysics and Physics.
Are you excited about any recent additions to “the universe”?
This past summer, we added the new cosmic microwave background (CMB) data that was collected by the Planck spacecraft. We debuted it in the Dome during one of our Astronomy Live programs, and people were very excited—everyone started clapping. It’s great to see people so enthusiastic about the universe. The CMB visualization also appears in the new Space Show, Dark Universe, which opens at the Museum on November 2.
Learn more about the new Hayden Planetarium Space Show, Dark Universe.