Meers Oppenheim et al 2020 ApJL 891 L9

Simulations and analytical theory showing that atmospheric flows originating in the Sun’s photosphere will frequently drive a previously unidentified thermal plasma instability that rapidly develops into turbulence.

Shunya Takekawa et al 2020 ApJ 890 167

A clump of gas within a high-velocity compact cloud near our galaxy’s center has kinematic structure that points to the presence of a quiescent black hole of ~10,000 solar masses — a candidate intermediate-mass black hole.

Kristine W. F. Lam et al 2020 AJ 159 120

A previously undetected outer planet has been discovered orbiting K2-146, a dwarf star that already hosts one known planet, a mini-Neptune; the two planets may be in a mean motion resonance.

C. Casentini et al 2020 ApJL 890 L32

Observations of two nearby repeating fast radio bursts using the AGILE gamma-ray space telescope place limits on their high-energy emission, further constraining underlying source models like magnetar outbursts.

Camilla Scolini et al 2020 ApJS 247 21

Analysis of the three successive coronal mass ejections that erupted from the Sun during 2017 September 4–6 shows how interactions between them led to the associated intense geomagnetic storm on September 7 at Earth.

S. Mau et al 2020 ApJ 890 136

Two ultra-faint stellar systems have been discovered around the Milky Way in early data from the DELVE survey; if confirmed, the first, Centaurus I, would be one of the brightest recently discovered ultra-faint dwarf galaxies.