Sky & Telescope - January 2024 - 8

NEWS NOTES
BLACK HOLES
Black Holes May
Have Formed by
Direct Collapse
ASTRONOMERS HAVE SPOTTED a
supermassive black hole in the early
universe that might have formed in the
implosion of a gargantuan gas cloud.
The black hole's host galaxy, UHZ1,
was spotted in James Webb Space Telescope
(JWST) observations of galaxies
in the early universe. Ákos Bogdán
(Center for Astrophysics, Harvard &
Smithsonian) and others followed up
on these galaxies using the Chandra
X-ray Observatory. One of the galaxies,
appearing to us from a mere 460
million years into cosmic history (at
a redshift of 10.3), boasts the classic
X-ray signature of a gigantic black hole
shrouded in gas. Based on the Chandra
 This artist's impression shows a supermassive
black hole girthed by dusty gas. The origins of
these objects are still under debate.
SOLAR SYSTEM
Osiris-REX Completes Sample Return from Asteroid Bennu
AFTER A JOURNEY of seven years and
7.1 billion kilometers (4.4 billion miles),
NASA's Origins, Spectral Interpretation,
Resource Identification, Security-Regolith
Explorer (Osiris-REX) spacecraft
has accomplished its primary mission: It
has brought back material grabbed from
the rubble-pile asteroid 101955 Bennu
(S&T: Feb. 2021, p. 8).
On September 24th, four hours prior
to touchdown, a coffee table-size capsule
separated from the spacecraft while
it was still more than 100,000 km away.
The capsule came in hot at 12 kilometers
per second (28,000 mph) over the
U.S. Department of Defense's Utah Test
and Training Range before landing at a
gentler 18 km/hr (11 mph) at 8:52 a.m.
local time. Teams sent in via helicopter
searched a 58-by-14-km reentry area,
and by 9:07 a.m., the team had located
the sample. The accomplishment is
NASA's first asteroid sample brought to
Earth for study.
The samples next made their way to
the Astromaterials Research & ExploraIN
BRIEF
pThe just-arrived capsule from Osiris-REX,
with a sample of asteroid Bennu inside, awaits
recovery on the Department of Defense's Utah
Test and Training Range.
8
JANUARY 2024 * SKY & TELESCOPE
Asteroid Bennu Has Layers
The asteroid 101955 Bennu is a so-called " rubble pile, " but close-up observations show
it is far from a random accumulation. Scientists analyzing data from NASA's Osiris-REX
report evidence in the December Icarus that underneath Bennu's rough surface, there's
an inner shell of finer particles that's 1-4 meters (3-14 feet) thick. The first clue came
from the spacecraft's high-resolution images of the asteroid, which revealed a texture
contrast between smaller and larger craters. Additional data from other Osiris-REX
instruments confirmed the difference. Edward B. Bierhaus (Lockheed Martin Space) and
colleagues conclude that the asteroid has a subsurface layer of particles finer than those
on the surface. Microimpacts may serve to shake smaller grains down between larger
surface rocks. These findings will help provide context for the sample recently acquired
from Bennu's surface.
¢JEFF HECHT
tion Science facility at NASA's Johnson
Space Center for study, evaluation, and
eventual sharing with international
partners. Scientists will not only weigh
the collected rocks but also begin
detailed investigations into the solar
system's early history.
With the capsule safely on the
ground, the mothership now has an
encore mission, with a new name:
Osiris-APEX. The spacecraft is headed
toward the near-Earth asteroid 99942
Apophis. It should reach the asteroid in
2029, just before the asteroid swings by
Earth in a close approach.
¢DAVID DICKINSON
ARTIST'S CONCEPT OF DIRECT-COLLAPSE BLACK HOLE: ESA / V. BECKMANN
(NASA GSFC); LANDING PHOTO OF CAPSULE: NASA / KEEGAN BARBER

Sky & Telescope - January 2024

Table of Contents for the Digital Edition of Sky & Telescope - January 2024