Webb Observations Released – NASA released the first full-color images and spectra taken by the James Webb Space Telescope, that weren’t alignment or test images. The telescope operates in infrared, so for humans to be able to see Webb images, the wavelengths detected are shifted to visible light wavelengths such that they appear to be color images. The selected images show various capabilities of Webb. The first released is the deepest image of distant galaxies ever taken in infrared, looking through a galaxy cluster known as SMACS 0723. It shows galaxies so distant that the light left there an estimated 300 million years after the Big Bang. The distant galaxies gain from the gravitational lensing effect of the closer galaxy cluster, which magnifies and brightens their light.
Other images are of the Eight-Burst or Southern Ring, a planetary nebula about 2,000 light-years away with unusual structure; Stephan’s Quintet, a grouping of galaxies in Pegasus of which four are gravitationally interacting, showing more detail than ever seen before, including tails of gas, dust and stars; a section of the Carina Nebula known as the Cosmic Cliffs, showing areas shaped by ultraviolet light and stellar winds from massive, hot stars; and Jupiter and some of its satellites, showing the planet’s faint rings.
The spectra are of some asteroids and of the atmosphere of a hot gaseous exoplanet known as WASP-96b. The planet’s spectra shows the signature of water and evidence of clouds and haze, while the asteroid data demonstrate Webb’s ability to track and observe moving objects.
Cosmic Ray Source – Cosmic rays are charged particles traveling nearly the speed of light. Though studied for more than a century, scientists still don’t know the source of them (except ones that come from our Sun) and how they attain such high speeds. The problem is that charged particles’ trajectories are bent by magnetic fields, so the direction they originate from is not the direction they strike Earth. But the production of cosmic rays is believed to also produce neutrinos, which are not charged and therefore travel in a straight line. A study by researchers at Clemson University using the IceCube neutrino detector at the South Pole shows that blazars produce high-energy neutrinos like those expected with cosmic rays. A blazar is a black hole at the center of a galaxy which is actively accreting matter and happens to have a jet of ejected ionized matter aimed nearly in our direction. More study of blazars is needed to determine how they accelerate charged particles and neutrinos to such high energies.
Accretion Disk With Arms – An international team of astronomers using the ALMA radiotelescope array in Chile discovered a young star that has an accretion disk with two spiral arms. Based on computer simulations, researchers think that the spiral arms were created when an object flew close by and gravitationally disturbed it more than 10,000 years ago. The star is still in the process of forming and now has a mass 32 times that of our Sun. It is among the most massive forming stars known to have an accretion disk, so little is understood of the role accretion disks play in forming massive stars. The disk is 2,000 times the diameter of the Earth’s orbit about the Sun.
Tidal Disruption Event – When a star approaches a black hole too closely, the tidal forces of the black hole tear apart the star in what is known as a tidal disruption event, or a TDE. Recent studies of TDEs show that much of the star’s mass is blown away by winds from the black hole. One recent TDE occurred in 2019 about 215 million light-years away and was observed in polarized light by astronomers at the University of California, Berkeley. The observations showed a spherical cloud of gas being blown out that obscured much of the high-energy emissions interior to the cloud. This explains why X-rays are often not seen from TDEs, though X-rays should be produced where material is falling into the black hole.
Star Orbiting Black Hole – Quite a few stars are known that orbit the supermassive black hole at the center of our Milky Way galaxy, with orbital periods ranging from 10 to 166 years. Another has been discovered by a research team at the Institute of Physics at the University of Cologne, this time with a period of only four years. It has been dubbed S4716. It is four times the mass of our Sun and orbits the black hole at a distance about 100 times the size of Earth’s orbit about the Sun. Like the other stars orbiting the galaxy center, this newly discovered one was found in infrared images, since infrared penetrates the dust between the galaxy center and us. It was then confirmed in archived infrared images.
Black Hole Orbiting Star – When black holes aren’t consuming substantial amounts of matter, they’re dormant and difficult to find as most are detected by the X-rays emitted from material falling in. Astronomers at KU Leuven discovered the first dormant black hole outside our galaxy in the Large Magellanic Cloud, a small satellite galaxy to the Milky Way. The motion of a 25 solar mass star indicated it was being orbited by an unseen object of about nine times the Sun’s mass. Astronomers measured the spectrum of that companion, and it showed no spectral lines. Other possible explanations were considered, but only the glow of a little material falling into a black hole fit all the observations. The glow is dim enough that the black hole is considered dormant. There has been no evidence of supernova remnant found, indicating that the black hole may have formed from the direct collapse of a star at the end of its life rather than forming as the collapsed core remaining after a supernova explosion blew away the outer parts of a star.
Speeding Pulsar – Astronomers at the Harvard & Smithsonian Center for Astrophysics discovered that a pulsar, known as G292.0+1.8, is speeding through space at over one million miles per hour. Although a few speeding pulsars are known, how they attained their speeds is still a mystery. The two leading theories are acceleration by neutrinos or by asymmetric supernova. Pulsars are believed to form as remnants of stars exploding as supernovas at the end of their lives. This pulsar is estimated to be about 2,000 years old.
Strongest Magnetic Field – Astronomers at the Chinese Academy of Sciences using the Chinese X-ray satellite Insight-HXMT have measured the strongest magnetic field ever, 1.6 billion Tesla, near the surface of an accreting pulsar known as Swift J 0243.6+6124. It is the first ultraluminous X-ray pulsar found within the Milky Way though several are known in other galaxies.
White Dwarf Consumes Planetary Matter – Astronomers observed for the first time a white dwarf star with orbiting debris captured from gravitationally broken up rocky and icy planets. The newly observed white dwarf, known as G238-44, must have disturbed both its inner and outer planetary systems, where respectively rocky and icy planets are formed. The disturbance would have occurred during the star’s red giant phase, where a star swells to huge size before collapsing to a white dwarf. The new observations by astronomers at the University of California, Los Angeles found nitrogen, oxygen, magnesium, silicon, iron and other elements. Studying shattered material being absorbed by white dwarfs gives astronomers an opportunity to see what its planets were made of internally.
Unusual FRB – Fast Radio Bursts (FRBs) as they travel toward us on Earth slow slightly because of the thin plasma that permeates space. That slowing is frequency dependent, so the farther the FRB has traveled, the more dispersed in time the burst becomes. This has been used to determine how far away FRBs originated. Occasionally an FRB has been pinpointed to originate in a particular galaxy, and other techniques to determine the distance to the galaxy itself have agreed with the time-dispersion distance estimate, until now. An FRB known as FRB190520 originated in a galaxy about three billion light-years away, but showed a dispersion distance 10 times as large. Astronomers are working on an explanation for this discrepancy. The FRB was discovered by researchers at West Virginia University using the FAST radiotelescope in China and was found to repeat more often than any other known FRB. Also making this FRB unusual is that there is a persistent weak radio signal in additional to the bursts.
Bennu Is Soft – Analysis of data from the OSIRIS-REx spacecraft during the time it touched its sample collector to the surface of asteroid Bennu shows that the surface material is extremely soft. The sampler penetrated farther than expected. Touching Bennu spit particles into space and left a much bigger crater than expected with much more debris around it. The scientists at the Southwest Research Institute and the University of Arizona, Tucson compared it to a plastic ball pit play area, where you sink in if you stay long. Astronomers will use this information for planning future asteroid missions and for determining how to divert asteroids in danger of colliding with Earth.
Martian Carbon – Carbon bound to hydrogen atoms is known as organic carbon and can be produced by both life and other non-biological processes as well. For the first time, researchers at NASA Goddard using the Mars Curiosity rover have been able to measure the total amount of organic carbon in a sample that the rover scooped up. The result is that 200-273 parts per million of the sample is organic carbon. It is not believed this was created by past life but was instead the building blocks that life could have arisen from billions of years ago when atmospheric and water conditions would have been conducive to life forming. The relative amounts of isotopes of carbon were also measured, but the result is not conclusive as to the source that created the carbon-hydrogen compounds. The data was collected eight years ago but took this long to analyze.
Curiosity Transition – During its climb up Mount Sharp, the Curiosity Mars rover has recently transitioned from a clay-rich zone to a sulfate-rich one. The clay formed from sediments in lakes and streams, while the sulfate formed in drier times making this transition a record of when the red planet’s climate dried up.
InSight – NASA has reversed its earlier decision about the demise of the InSight Mars lander. The agency had announced that the seismometer would be shut down soon to conserve electricity as power from the solar panel dwindled with accumulating dust. The new decision is that the seismometer data is the most valuable scientifically, so the instrument will be left on as long as possible, taking all other measures to reduce electrical usage, including turning off the fault protection system.
Mars Radar Upgraded – The MARSIS instrument aboard the European Space Agency’s Mars Express spacecraft has been taking radar observations of Mars for nearly two decades. Its signal penetrates a few kilometers below the surface, telling scientists properties of the surface and subsurface. The MARSIS team has prepared a software upgrade to allow the instrument to improve signal reception and to preprocess the data before reporting it to Earth. This will reduce use of onboard storage and the radio relays to Earth. As a result, much longer runs of data collection with better resolution will be possible.
CAPSTONE Launched – The Lunar Gateway, a future space station to orbit the Moon, will use a unique orbit that is over the poles and has a rather low point, or “periselene” and an extremely high “aposelene.” Lunar orbits are notoriously unstable due to the uneven mass distribution in the Moon and the disturbing influence of Earth’s gravity. To test the Gateway orbit, NASA launched a small satellite named CAPSTONE near the end of June using the Gateway orbit. It will take four months to reach that orbit, and then spend at least six months testing dynamics and stability. CAPSTONE will also test a navigation and communications system that utilizes the Lunar Reconnaissance Orbiter. CAPSTONE was launched from New Zealand using an Electron rocket.
Psyche Won’t Launch – NASA announced that it will miss the planned fall 2022 launch of the Psyche mission to asteroid Psyche. Alternate launch opportunities in 2023 and 2024 are being considered, but those would result in delay of three to four years in arrival and increased costs. The launch date cancellation is due to problems found in flight software and testing equipment resulting in insufficient time to fully test the corrections before the October launch deadline, dictated by planetary positions. Psyche is an unusual asteroid in that its density is high, indicating a probable high content of iron. No iron-rich asteroid has been visited by spacecraft.
