Nancy A. Levenson
Science Highlights
Figure 1.
The relationship
between core radius
(rb) and the black hole
sphere of influence
(rSOI) is tighter than
other relationships with
the black hole mass,
such as stellar velocity
dispersion.
In these summaries from recent papers based on Gemini data,
we explore an unexpected 17-billion-solar-mass black hole in an
unlikely galaxy, track a young planet’s orbit in the disk of the HD
95086 planetary system, reveal the story behind our cover image
of the young star-forming region N159W in the Large Magellanic
Cloud, and investigate a “hot Jupiter” with GRACES.
A 17-Billion-Solar-Mass Black Hole Surprise
Astronomers using the Gemini Multi-Object Spectrograph (GMOS) integral field unit on the
Gemini North telescope have measured a 17-billion-solar-mass black hole dominating the
core of NGC 1600, a large galaxy in the low-density environment of a
galaxy group. This is a surprise, given that we expect to find monster
black holes in very massive galaxies at the centers of large galaxy clusters. Astronomers have also observed luminous quasars hosting very
massive black holes in the distant Universe, and this result sheds light
on large black holes in the more local Universe, suggesting they are
likely relics, the descendants of luminous quasars at higher redshift.
In the high-mass regime, Jens Thomas (Max Planck Institute for Extraterrestrial Physics, Germany) and collaborators find that a host galaxy’s
core radius is a robust proxy for the mass of the central supermassive
black hole; it correlates more tightly than stellar velocity dispersion, σ.
NGC 1600 is, in fact, something of an outlier on the more common “Mσ” plot. Figure 1 shows the relationship between this core radius (rb)
and the black hole sphere of influence (rSOI). A Gemini press release
features the work, and complete results are published in Nature.
8
GeminiFocus
July 2016