A closer look at the spur, blob, wiggle, and gaps in GD-1

Understand

The GD-1 stream is one of the longest and coldest stellar streams discovered to date, and one of the best objects for constraining the dark matter properties of the Milky Way.

• Using data from {\it Gaia} DR2 we study the proper motions, distance, morphology and density of the stream to uncover small scale perturbations.
• The proper motion cleaned data shows a clear distance gradient across the stream, ranging from 7 to 12 kpc.
• However, unlike earlier studies that found a continuous gradient, we uncover a distance minimum at $\varphi_{1}\approx$-50 deg, after which the distance increases again.