A team of U-M researchers were studying dark energy, the effects of which can only be seen by observing other galaxies far outside our own solar system. But their extremely sensitive camera also picked up hundreds of small, icy worlds much closer to home—in the cloud of dust, rocks, and planetoids known as the Kuiper Belt.

One of these objects was an undiscovered dwarf planet orbiting far beyond Neptune. A graduate student on the team nicknamed it “DeeDee,” short for “Distant Dwarf.”

Meet David Gerdes

David Gerdes, PhD, is Arthur F. Thurnau Professor of Physics and Professor of Astronomy at the University of Michigan.

Supported by the National Science Foundation and NASA.

 

The Dark Energy Survey

The Dark Energy Survey (DES) is a project that observes 1/8 of the sky using a special 570-megapixel camera mounted on the 4-meter Blanco telescope located in the Chilean Andes.

 

Analyzing the DES Data Set

The Dark Energy Survey has created a huge data set and uses powerful computers to analyze billions of objects in the sky.

 

Distance

Neptune represents the edge of the region of the solar system that contains planets, and it's about 30 times Earth's distance from the sun (30 au).

 

Intelligent Life

The solar system doesn't end at the four giant planets. This region is home to Pluto and other small objects called Kuiper Belt Objects, or Trans Neptunian Objects (TNOs).

 

Discovering DeeDee

An unusual data point found in the summer of 2016 led to a surprising discovery.

 

Collaborators

A community of scientists around the world has collaborated on the Dark Energy Survery.

 

Meet Larissa Markwardt

University of Michigan grad student Larissa Markwardt collects data with the Dark Energy Camera at Fermilab outside of Chicago.

 

 

 

 

 

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