Does Dark Matter Matter?

Astronomers have detected a galaxy that seems to be devoid of dark matter. That possibility has theorists re-evaluating gravity’s role in keeping a galaxy intact.
A Columbia University-led team of astrophysicists has completed a study suggesting the presence of as many as 10,000 very small, low-energy black holes near the core of our galaxy. The mini-black holes have never been detected before because instrumentation has always been tuned to see the more energetic variety of black holes.
Dark sky highlights this week:
Planets; Jupiter in the east after 10 p.m., Saturn, Mars in the south, pre-dawn with Jupiter in the west about to set.
Notable stars: Sirius: brightest in our sky, Arcturus: 4th brightest in our sky, and Betelgeuse: 9th brightest star, a red supergiant; if it were centered here, it would extend beyond Earth (and Mars).