Pic of the Week: Ghostly Apparitions

Posted on by onespaceman2000
Image (Credit): Constellation of Cepheus. (Bogdan Jarzyna)

I wanted to share one more image before we leave Halloween behind, this time from NASA’s Astronomy Picture of the Day.

Here is a description from NASA regarding the image above:

The jeweled expanse, filled with faint, starlight-reflecting clouds, drifts through the night in the royal constellation of Cepheus. Far from your own neighborhood on planet Earth, these ghostly apparitions lurk along the plane of the Milky Way at the edge of the Cepheus Flare molecular cloud complex some 1,200 light-years away. Over two light-years across and brighter than the other spooky chimeras, VdB 141 or Sh2-136 is also known as the Ghost Nebula, seen toward the bottom of the featured image. Within the reflection nebula are the telltale signs of dense cores collapsing in the early stages of star formation.

Television/Book Review: Beacon 23

Posted on by onespaceman2000

You probably already subscribe to half a dozen streaming platforms, but does it include MGM+ (formerly known as Epix)? If not, you will miss the November 12th premiere of a new eight-episode series called Beacon 23.

Here is the basic story from MGM+ (and here is the trailer):

Beacon 23 takes place in the farthest reaches of the Milky Way and follows Aster (Lena Headey), a government agent, and Halan (Stephan James), a stoic ex-military man, whose fates become entangled after they find themselves trapped together inside one of many Beacons that serve as a lighthouse for intergalactic travelers. Every Beacon is run by one highly trained human and a specialized Artificial Intelligence. Aster mysteriously finds her way to the lonely Beacon-keeper Halan, and a tense battle of wills unfolds. Halan begins to question whether Aster is friend or foe, as her ability to disguise her agenda and motives could make her a formidable opponent.

It looks intriguing. And the anticipation has been building since this project was announced more than two-and-a-half years ago (in the middle of Covid). Luckily, not even the writers strike killed this one.

It is based on the book of the same name, which had good reviews. Here are a few comments on the book:

—It’s a quick, easy read, especially since most of the events involve only one character. It’s quite good in its way, too, a bit like “The Martian” if the astronaut in that novel had just kind of hung out back in the Hab without working very hard on his survival. Our hero is flawed, hailed for an act that he views as cowardly, and in the end readers are left to wonder if he’s actually a hero or a fool. (The Oklahoman)

—It’s a book for adult readers, but I think younger readers would have a lot of fun with it. The voice is irresistible and it’s both funny and sad. In some ways it’s a cross between Andy Weir’s The Martian and David Bowie’s Space Oddity. Beacon 23 tells the story of a man whose job it is to stand sentry in what is effectively an interstellar lighthouse, making sure passing ships don’t crash into nearby asteroids. The main character’s name is never given, and the story is told in the first person so it could almost be anyone’s story. It’s very easy to relate to the narrator who is ex-military and living out his retirement all alone in the beacon with only his thoughts and the odd (often wry and hilarious) communications with NASA to keep him company. (Luna Station Quarterly)

—Beacon 23 is a loose combination of Dark Star and The Martian. At times I found the story very funny, particularly the dialogue with Rocky, as well as some interesting interchanges with NASA, imagined and real. There are also the inevitable technical issues to overcome when you are on your own and help is not an inconsiderable distance away. And to top it all the Operator of Beacon 23 is almost certainly suffering from Post Traumatic Stress Disorder, or in his own words “…just a little bit crazy.” (Book Lore)

I guess the key point in all of these is that the story reminds them of The Martian. All you need now is one more streaming platform. Or you can await broader distribution of the series. Whichever way you go, this one may be worth a second look.

Space Stories: Dinosaur Dust, Missing Stars, and SETI Signals

Posted on by onespaceman2000
Image (Credit): The end of the dinosaurs. (NYT, Roger Harris/Science Source)

Here are some recent stories of interest.

—Royal Observatory of Belgium: “Dust Played a Major Role in Dinosaur Demise“

Fine dust from pulverized rock generated by the Chicxulub impact likely played a dominant role in global climate cooling and the disruption of photosynthesis following the event. This is suggested by a new study published in Nature Geoscience, in which researchers Cem Berk Cenel, Özgür Karatekin and Orkun Temel of the Royal Observatory of Belgium contributed.

—Express: “Astronomers Trying to Unravel Mystery of Three Stars that Suddenly Disappeared from Sky“

A team of Spanish astronomers is leading the investigation into one of stargazing’s most perplexing mysteries. Three bright stars photographed in the night sky above southern California in 1952 vanished just an hour later. Generations of scientists have sought to explain the rare phenomenon over the past half-century, but nothing has yet convinced the community. Researchers at the Centre for Astrobiology (CAB) in Madrid tried to solve the riddle of the “triple transient” that has “remained absent from telescope exposures for 71 years” in a new paper published online.

—Sci.News: “New Study Sets Clearer Bounds on Search for Technosignatures from Extraterrestrial Intelligences“

A stable-frequency transmitter with relative radial acceleration to a receiver will show a change in received frequency over time, known as a ‘drift rate.’ For a transmission from an exoplanet, astronomers must account for multiple components of drift rate: the exoplanet’s orbit and rotation, the Earth’s orbit and rotation, and other contributions. Understanding the drift rate distribution produced by exoplanets relative to Earth, can help scientists constrain the range of drift rates to check in a Search for Extraterrestrial Intelligence (SETI) project to detect radio technosignatures, and help them decide validity of signals-of-interest, as they can compare drifting signals with expected drift rates from the target star. In a new study, University of California, Los Angeles astronomer Megan Grace Li and colleagues modeled the drift rate distribution for over 5,300 confirmed exoplanets, using parameters from the NASA Exoplanet Archive.

Study Findings: A Planetary Collision Afterglow and Transit of the Resultant Debris Cloud

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Image (Credit): Artist’s rendering of two colliding planets. (NASA)

Nature abstract of the study findings:

Planets grow in rotating disks of dust and gas around forming stars, some of which can subsequently collide in giant impacts after the gas component is removed from the disk. Monitoring programmes with the warm Spitzer mission have recorded substantial and rapid changes in mid-infrared output for several stars, interpreted as variations in the surface area of warm, dusty material ejected by planetary-scale collisions and heated by the central star: for example, NGC 2354–ID8, HD 166191 and V488 Persei. Here we report combined observations of the young (about 300 million years old), solar-like star ASASSN-21qj: an infrared brightening consistent with a blackbody temperature of 1,000 Kelvin and a luminosity that is 4 percent that of the star lasting for about 1,000 days, partially overlapping in time with a complex and deep, wavelength-dependent optical eclipse that lasted for about 500 days. The optical eclipse started 2.5 years after the infrared brightening, implying an orbital period of at least that duration. These observations are consistent with a collision between two exoplanets of several to tens of Earth masses at 2–16 astronomical units from the central star. Such an impact produces a hot, highly extended post-impact remnant with sufficient luminosity to explain the infrared observations. Transit of the impact debris, sheared by orbital motion into a long cloud, causes the subsequent complex eclipse of the host star.

Citation: Kenworthy, M., Lock, S., Kennedy, G. et al. A planetary collision afterglow and transit of the resultant debris cloud. Nature 622, 251–254 (2023).
https://doi.org/10.1038/s41586-023-06573-9

Study-related stories:

A Day in Astronomy: Flyby of Asteroid Gaspra

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Image (Credit): Asteroid Gaspra as photographed by the Galileo spacecraft. (NASA)

On this day in 1991, NASA’s Galileo spacecraft conducted a flyby of asteroid Gaspra, an asteroid that orbits in the asteroid belt between Mars and Jupiter. The asteroid is about 10.5 miles long. Gaspra was discovered in 1916 by Russian astronomer G. N. Neujmin, who named it after a famous Russian spa retreat in Crimea.

The Galileo spacecraft’s primary mission was to visit Jupiter and its moons, but it also conducted other observations along the way, including flybys of asteroids Gaspra and Ida.

Here are a few facts about the Galileo mission from NASA:

  • Galileo was the first spacecraft to orbit an outer planet.
  • It was the first spacecraft to deploy an entry probe into an outer planet’s atmosphere.
  • It completed the first flyby and imaging of an asteroid (Gaspra, and later, Ida).
  • It made the first, and so far only, direct observation of a comet colliding with a planet’s atmosphere (Shoemaker-Levy 9).
  • It was the first spacecraft to operate in a giant planet magnetosphere long enough to identify its global structure and to investigate its dynamics.