Eric Walker added A Black Hole’s Boomerangs - The New York Times to a number of topics

Eric Walker added a number of topics and r/geology - The Dee Wright Observatory in Sisters, Oregon. It sits in the middle of a lava flow and made of the rocks it surrounds. to Telescopes, observatories and telescope networks, and added Telescopes, observatories and telescope networks to Astronomy, astrophysics and cosmology and Measuring instruments and measurement techniques

Eric Walker added A Black Hole’s Boomerangs - The New York Times to Square Kilometer Array, and added Square Kilometer Array to Telescopes, observatories and telescope networks