Sky & Telescope - November 2022 - 10

NEWS NOTES
BLACK HOLES
Where Did the First Quasars Come From?
JUST 700 MILLION YEARS after the Big
Bang, we already see supermassive black
holes with the heft of 1 billion Suns.
Now, a team of astronomers is using
computer simulations to demonstrate
the formation of these dark behemoths.
In their scenario, massive clouds of
pristine gas collapse directly into black
holes in the early universe. (See page
16 for other options for making " black
hole seeds. " ) The calculations for such
massive implosions are delicate, though.
What's to prevent the gas cloud from
fragmenting and forming smaller stars,
as the ones in the modern universe are
wont to do?
Previously, astronomers have suggested
the ultraviolet emission of nearby
newborn stars might have heated the
gas, keeping it too warm to fragment.
But such specific requirements would
have made the process rare.
Now, Muhammad Latif (United Arab
Emirates University), Daniel Whalen
IN BRIEF
A Burst with a Heartbeat
The discovery of a pulsing fast radio burst
(FRB) provides fresh evidence in support of
neutron star origins for these brief and mysterious
flashes. The Canadian Hydrogen Intensity
Mapping Experiment (CHIME) telescope in
British Columbia has cataloged several hundred
FRBs since it came online, but its most
recent FRB sighting, featured in the July 14th
Nature, is unique. The unusually long flash,
which lasted three seconds (much longer than
the average burst), contained nine heartbeatlike
pulses. The team contends that this
strange FRB originates in or around a neutron
star. " This signal, with an imprinted periodicity,
could be the clue that at least some FRBs
are produced by rotating neutron stars, "
agrees Jens Mahlmann (Princeton), who was
not involved in this study. " Their spinning
magnetic fields may play an important role for
explaining subpopulations of FRBs. "
¢ARWEN RIMMER
Booster Impact Found
NASA's Lunar Reconnaissance Orbiter
(LRO) has imaged the impact site created
10 NOVEMBER 2022 * SKY & TELESCOPE
a clump took shape, and then another.
The turbulence of the inrushing gas
flows kept the massive clumps from collapsing
straightaway into stars. By the
end of the simulation's first stage, each
clump contained tens of thousands of
Suns' worth of mass.
In a separate simulation, the
pRivers of gas rush into a central, churning
sea, in which two massive primordial black
holes are forming.
(University of Portsmouth, UK), and
colleagues report in the July 7th Nature
that intense turbulence might have
blocked fragmentation.
In computer simulations that rebuild
the conditions of the universe when it
was around 100 million years old, the
team followed the growth of a small,
frothing sea of matter fed by four torrents
of inflowing gas. Within the sea,
by a rocket booster hitting the farside of the
Moon on March 4th (S&T: June 2022, p. 11).
Observers had spotted the object on a Moonbound
trajectory, but the impact itself was
of course out of Earth's line of sight. Initial
calculations suggested the object was the
second stage of the SpaceX Falcon 9 rocket
that had launched the Deep Space Climate
Observatory mission in 2015. But observers
later refined the trajectory and identified the
object as a Long March 3C upper stage from
China's Chang'e 5 T1 mission, which flew
around the Moon in late 2014. To date, China
hasn't confirmed the identification. The LRO
team found the impact site about 8 kilometers
(5 miles) from the JPL predictions, a slight
shift that may have been caused by the gentle
push of the solar wind. Surprisingly, the image
revealed a pair of craters: one to the east 18
meters across superimposed on a 16-meter
western crater. Most of the mass from the
spent Chang'e 5 T1 booster was expected to
be located in the motor end, but the double
crater indicates a large mass on both ends.
LRO images of Apollo booster impacts show
craters of similar sizes, but while some of
them are irregular, none are double.
¢DAVID DICKINSON
See the image at https://is.gd/farside.
researchers then show that the two
clumps would compress into supermassive
stars, which would last perhaps 2
million years before collapsing further
into black holes of 30,000 and 40,000
solar masses, respectively.
The team estimates that such a
confluence of cosmic rivers would have
been common enough to explain observations
of early quasars.
Priyamvada Natarajan (Yale), who
wasn't involved in the study, agrees that
the simulation presents a natural pathway
for the formation of massive black
hole seeds. But she adds that it's not a
unique solution; other environments,
such as a dense star cluster, could
enable direct collapse, too.
¢MONICA YOUNG
Capstone Cubesat Launches
A NASA CubeSat designed to test a unique
lunar orbit is safely in space. The Cislunar
Autonomous Positioning System Technology
Operations and Navigation Experiment
(Capstone) successfully lifted off on a Rocket
Lab Electron rocket. Despite an early communications
hiccup, the CubeSat was able to
separate from the rocket and head toward the
Moon on a ballistic lunar transfer orbit. The
meandering path has Capstone arriving at the
Moon on November 13th, where it will enter a
highly inclined and elongated near-rectilinear
halo orbit. The crewed Lunar Gateway platform
of the Artemis mission will eventually use
the same orbit: It's stable, requires relatively
little fuel for station-keeping, and allows
access to the lunar poles for crewed landing
missions. Capstone will demonstrate this orbit
for six months, passing 1,610 kilometers from
the lunar surface over the Moon's north pole,
and 70,000 kilometers from the Moon's south
pole, once every 6½ days. Capstone will
also test autonomous communications with
NASA's Lunar Reconnaissance Orbiter. The
first launch for the Lunar Gateway is currently
scheduled for late 2024.
¢DAVID DICKINSON
DANIEL WHALEN (UNIVERSITY OF PORTSMOUTH, UK)
https://www.is.gd/farside
Sky & Telescope - November 2022

Table of Contents for the Digital Edition of Sky & Telescope - November 2022
