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Black hole at center of Milky Way may be blasting out a jet

https://www.science.org/content/article/black-hole-center-milky-way-may-be-blasting-out-jet   By DANIEL CLERY , Science.  Excerpt: The supermassive black holes at the centers of many galaxies generate powerful jets, blasting particles thousands of light-years into space. This new image of the Milky Way’s black hole, known as Sagittarius A* (Sgr A*), suggests it may have one, too, but perhaps of a more modest nature. The image—taken with polarized light—was  released today by the Event Horizon Telescope (EHT) , a worldwide array of radio telescopes that in 2019 produced the  first ever image of a black hole . The new image shows light that is oriented in a particular direction, revealing magnetic field lines around the black hole. Although jets would not be visible in such a zoomed-in image, strong magnetic fields are thought to be essential in launching them.... See also European Southern Observatory press release . 

Number of known moonquakes tripled with discovery in Apollo archive

https://www.science.org/content/article/number-known-moonquakes-tripled-discovery-apollo-archive By  PAUL VOOSEN , Science Excerpt:  THE WOODLANDS, TEXAS— The Moon suddenly seems more alive. From 1969 to 1977, seismometers left on the lunar surface by the Apollo astronauts detected thousands of distinctive “moonquakes.” Now, half a century later, a new analysis has cut through the noise in the old data and nearly tripled the number of moonquakes, adding more than 22,000 new quakes to 13,000 previously identified ones.  The finding,  presented  last week here at the Lunar and Planetary Science Conference, shows “that the Moon may be more seismically and tectonically active today than we had thought,” says Jeffrey Andrews-Hanna, a geophysicist at the University of Arizona unaffiliated with the work, which is  in review  at the  Journal of Geophysical Research . “It is incredible that after 50 years we are still finding new surprises in the data.”

Why It’s So Challenging to Land Upright on the Moon

https://www.nytimes.com/2024/03/04/science/moon-landing-sideways-gravity.html By Kenneth Chang , The New York Times.  Excerpt: When the robotic lander  Odysseus last month became the first American-built spacecraft to touch down on the moon  in more than 50 years, it toppled over at an angle. ...Just a month earlier, another spacecraft, the Smart Lander for Investigating Moon, or SLIM, sent by the Japanese space agency, had also tipped during landing,  ending up on its head . ...people pointed to the height of the Odysseus lander — 14 feet from the bottom of the landing feet to the solar arrays at the top — as a contributing factor for its off-kilter touchdown. ...Philip Metzger, a former NASA engineer who is now a planetary scientist at the University of Central Florida, explained  the math and the physics  of why it is more difficult to remain standing on the moon. ...“The side motion that can tip a lander of that size is only a few meters per second in lunar gravity.” ...Odysseus wa

Stellar remains of famed 1987 supernova found at last

https://www.science.org/content/article/stellar-remains-famed-1987-supernova-found-last By DANIEL CLERY , Science.  Excerpt: When a nearby star exploded in 1987, it created the first supernova visible to the naked eye in 4 centuries and became one of the most intensely studied objects in space. Now, after more than 35 years of searching, researchers have finally discovered the cinder left behind. Using NASA’s new giant space telescope JWST, astronomers spotted  glowing gas at the center of the blast that can only have been energized by something hot and compact inside it , they report this week in Science. They believe a neutron star, all that remains of the shattered star, is responsible.... 

Seeking clear skies and quiet, astronomers put telescopes on U.S. Moon lander

https://www.science.org/content/article/seeking-clear-skies-and-quiet-astronomers-put-telescopes-u-s-moon-lander By DANIEL CLERY , Science. Excerpt: Small scopes on IM-1 mission would be first optical and radio observatories on the lunar surface. ...Astronomers have long eyed the Moon as  a good spot to do their work . Its far side, protected from Earth’s hectic radio noise, is perfect for picking up faint signals from the distant universe. To see infrared signals ... Put the telescope into one of the deep craters at the lunar poles that never receive any sunlight and its sensors will benefit from the crater’s permanent chill....

What Does a Solar Eclipse on Mars Look Like? New, Breathtaking Images, Caught by NASA’s Perseverance Rover, Give Us an Idea

https://www.smithsonianmag.com/smart-news/what-does-solar-eclipse-mars-look-like-new-breathtaking-images-caught-nasa-perseverance-rover-idea-180983795/ By Carlyn Kranking , Smithsonian Magazine.  Excerpt: The robot recently observed each of the Red Planet’s moons passing across the sun in the Martian sky [see photo in this article]. 

Planets around dead stars offer glimpse of the Solar System’s future—after the Sun swallows us up

https://www.science.org/content/article/planets-around-dead-stars-offer-glimpse-solar-system-s-future-after-sun-swallows-us By JONATHAN O’CALLAGHAN , Science.  Excerpt: In about 5 billion years the Sun will balloon up into a red giant, consuming Mercury, probably Venus, and maybe even Earth. But even if the outer planets avoid being swallowed up, they might eventually get pulled in or ejected from the Solar System. A new discovery suggests they can survive intact. Using NASA’s JWST space telescope, astronomers have for the first time directly imaged planets on Solar System–like orbits around white dwarfs, the dead stars left after Sun-like stars swell into red giants and subside. The planets follow orbits resembling those of the giant planets in the outer Solar System—big enough for them to have escaped the inferno.... For GSS A Changing Cosmos chapter 1.