More space news!

[DShomshak]

Meanwhile, the November '21 issue of Scientific American features a photo essay on prepping the James Webb Space Telescope for launch. I did not expect so much gold foil. Read to find out why.

 

Also a small story about an alternate geological history for Gale Crater and Mount Sharp on Mars, based on the information from the Curiosity rover: not a deep, long-lasting lake but small, brief puddles. Unfortunately, the nearest equipment that could resolve the question is on the Perseverence rover, thousands of kilometers away.

 

Also a short article that links geology, microbiology and astrophysics. An interdisciplinary study suggests connections between changes in the length of Earth's day and the appearance of free oxygen in eary Earth's atmosphere. Possibly worth the attention of SF worldbuilders.

 

Dean Shomshak

[Cancer]

On 11/18/2021 at 11:06 AM, DShomshak said:

NOVA has been showing another astronomy m ini-series, "Universe Revealed," with episodes about Stars, the Milky Way, Alien Worlds, Black Holes, and (upcoming) the Big Bang. The CGI has been pretty. Milky Way and Alien Worlds had some information that was new to me, such as that the GAIA mission found a population of stars that orbit gthe Milky Way in retrograde, from which astronomers infer a galaxy (dubbed GAIA-Enceladus) that the Milky Way absorbed several billion years ago.

 

But the programs are marred by not enough airtime spent explaining why astronomers believe various results are true, and too much airtime on astronomers waving their arms while saying how amazing something is. Plus the usual banalities about Knowing Where We Came From and Why It Matters. (Note to science program writers: We wouldn't be watching if we didn't already think it was cool and it mattered. So don't waste our time selling the subject.) Some attempts to explain things in "common person" terms, such as comparing black holes to waterfalls, were more bizarre than useful. And some information was, if not false, then sufficiently lacking in context that I consider it misleading.

 

Maybe all the background explanations are given in supplemental material online, making the aired program a sort of extended trailer to entice people to the real content. I didn't look to see, because I would still consider that bad writing. All in all, "Universe Revealed" has been a disappointment.

 

Dean Shomshak

 

Dean, you're experiencing the curse of the educated layman.  There aren't many venues where one can reliably find science material between the level you describe above and the level where you're in upper-level textbooks or reviews in the technical literature, and approximately none of those venues are in broadcast media.  I ran up against this same problem when I was in my teens.  Scientific American magazine (and while it existed, its book series) almost bridges that gap.  American Scientist does also, but it's only a bimonthly so there are fewer total articles in that publication, and so fewer space science/astronomy articles that appear there.  Sky and Telescope has a historical emphasis on amateur astronomy, including telescope making, how to do things in your backyard observatory, etc., and not much discussion of astrophysics ends up there.

 

Broadcast media are worse, and I say that as someone who was tech editor for the Star Date radio series for 5 years or so back in the 1980s.  The constraints in media production are all but stifling, with your air time budgeted by the literal second.  Since broadcast media always have as part of their agenda hooking in fresh consumers of their product, science broadcast shows always have to start at pretty basic levels and build up to new stuff, which costs you time once you get to that new stuff.  Finally, you need a really sympathetic senior editor to let the writers keep technically accurate stuff in and similar-sounding but hopelessly wrong material out; all their working lives, editors have been trained to smooth out English writing to please the ear, and when that sense of writing aesthetics bumps into the limitations of non-technical language, well, 90+% of the time the tech stuff gets smeared out.  Something I think I have said before in this forum: for those science stories that have reached the popular press where I have had first-hand knowledge of the original material/presentation/science, literally 100% of those stories have had something wrong (and not minorly wrong).  This includes articles in and from the New York Times, who are far better at this than most other venues.  The editors don't have the time to learn why the tech language is so stridently different in its subtle details from mainstream language -- as they will tell you whenever you complain, they have deadlines -- and since they get the last word, they win.

 

Also, frankly, often it takes a couple of years for new findings to be digested by the scientific community and something like a consensus to be reached, and that process is just about invisible to outsiders.  For those in the science community but outside the circles of the immediate workers in a subfield, review papers are the gateway, and those appear in a variety of places.  The Annual Reviews of Astronomy and Astrophysics are fairly far along in that pipeline.  You can go to their site, and for old issues (I think more than 10 years old) you can download articles for free; newer ones are behind the paywall.  OTOH, those are written for practitioners in the science, so the language is full-on technical.  Still, as a senior undergrad or first-year grad student, you'll get directed to some of these by professors if you're starting out in some topic.  Other high-quality review papers unfortunately tend to appear in conference proceedings books, which are rare (university libraries at institutions with departments in the field) and otherwise contain lots of papers mostly of little significance and will be generally impenetrable to anyone outside the immediate field.

 

Some intermediate-level reliable stuff appears on the Web.  If you have adequate bandwidth, see if you can get onto the Nature Briefings mailing list.  That'll be daily email of tech bits (all fields) from Nature with links to articles that are mostly not behind paywalls.  If you have trouble finding that, PM me and I'll see if I can send you a link.

[Cancer]

As an addendum to the above: starting with the new year, the American Astronomical Society journals (Astrophysical Journal, Astronomical Journal) will be full open access.  Those are technical journals, and most of the contents will be more or less impossible to read without a lot of help.  But at least you will be able to get to them for free.

[Ragitsu]

Physicist David Wiltshire estimated that due to the effects of general relativity, time passes about 38% faster in cosmological voids (large, empty pockets of space between galaxy clusters) than in the Milky Way.

[DShomshak]

https://www.vice.com/en/article/qj8jaq/vast-strands-in-the-cosmic-web-that-connects-the-universe-are-spinning-scientists-find

 

Do galaxies just whiz around at random? Maybe not: This study finds evidence that the immense strands of dark matter that comprise the "cosmic web" are spinning. Or at least the galaxies embedded within the strands are moving in corkscrew paths. What does it mean? The authors aren't sure. But they suspect it's a clue to some deeper order in the plan of the universe.

 

Dean Shomshak

 

[Ragitsu]

"Plan of the universe."?

[novi]

On 12/2/2021 at 10:07 PM, Ragitsu said:

Physicist David Wiltshire estimated that due to the effects of general relativity, time passes about 38% faster in cosmological voids (large, empty pockets of space between galaxy clusters) than in the Milky Way.

Yes, but he is working with a non-standard version of cosmology and general relativity, so don't put too much confidence in those results (yet).  He is part of a camp that is trying to find alternatives to dark energy.  Their hypothesis is that instead of dark energy, massive structures (or lack thereof) warp time more than conventional models assume, and can account for the apparent accelerating expansion of the universe.

 

It's not an unreasonable concept - the equations of General Relativity are notoriously complex, and cosmologists often use approximations that would make an engineer blush to simplify them to a level that can be computed.  As I understand it, more work is necessary to determine if this new approach to GR is compatible with the rest of our universe.

 

A few more words in explanation:  https://en.wikipedia.org/wiki/Inhomogeneous_cosmology

[DShomshak]

12 hours ago, Ragitsu said:

"Plan of the universe."?

My bad phrasing, not theirs. "Structure" might be a better word.

 

Dean Shomshak

[tkdguy]

Don't miss this event!

 

 

[Cancer]

Thanks for that, but with the weather we are having up here in the Great NorthWet I figure my chances to see it are just  about nil.  The only remotely favorable forecast was two mornings ago, and while I got up pre-dawn to look, the fog had rolled in and there was no sky to see.  At least the flood warnings have subsided for a little while up here....

[tkdguy]

5 hours ago, Cancer said:

Thanks for that, but with the weather we are having up here in the Great NorthWet I figure my chances to see it are just  about nil.  The only remotely favorable forecast was two mornings ago, and while I got up pre-dawn to look, the fog had rolled in and there was no sky to see.  At least the flood warnings have subsided for a little while up here....

 

Actually, it's the same thing over here. It has been overcast the last couple of days and nights. That seems to be the case every time there's an astronomical event to see, at least in the last few years.

[Scott Ruggels]

Accidental Wap bubble creation in the lab. 

 

https://stealthoptional.com/news/warp-bubble-darpa/

[DShomshak]

I heard about this on the BBC a few days ago. Here's a news story.

 

http://www.sci-news.com/astronomy/wide-orbit-gas-giant-b-centauri-10351.html

 

In brief: A planet estimated 10 times larger than Jupiter, found orbiting a massive B-type star (3x hotter than the sun and far more luminous) -- and a binary star as well -- and its distance from its star is 100x Jupiter's distance from the Sun. Oh, and it's directly imaged. It pushes the boundaries of what was thought possible for exoplanets, in multiple ways.

 

Dean Shomshak

 

 

[dmjalund]

1 hour ago, DShomshak said:

I heard about this on the BBC a few days ago. Here's a news story.

 

http://www.sci-news.com/astronomy/wide-orbit-gas-giant-b-centauri-10351.html

 

In brief: A planet estimated 10 times larger than Jupiter, found orbiting a massive B-type star (3x hotter than the sun and far more luminous) -- and a binary star as well -- and its distance from its star is 100x Jupiter's distance from the Sun. Oh, and it's directly imaged. It pushes the boundaries of what was thought possible for exoplanets, in multiple ways.

 

Dean Shomshak

 

 

is it a close binary (i.e. is the planet orbiting both suns?)

[Cancer]

Yes (reading the technical paper in Nature), the planet is circumbinary.  Not much is known about the fainter star in the binary system; the two stars are too close. 

 

Not many planets are known to be associated with B stars (though there's some selection effects that mean that spectroscopic binary detection can't work for B star systems), and not many are known with multi-hundred-AU orbit sizes (though again there are selection effects operating against finding such things).

 

With the planet being something like 560 AU from the pair of stars and more likely than not being in a not-highly-eccentric orbit, the planet will probably survive the death of the brighter star (by which I mean: the planet won't be destroyed by being engulfed by the star when the latter becomes a giant or supergiant), which is probably not that far away.  The system seems to belong to the Sco-Cen association, which is about 15 Myr old; the brighter star is about 6 solar masses and its main sequence lifetime is about 20 Myr.  That probably means the planet will become a free-floating one once the stars are both gone.

[Scott Ruggels]

more info on the accidental Warp bubble creation in the lab. 

 

https://thedebrief.org/darpa-funded-researchers-accidentally-create-the-worlds-first-warp-bubble/

[tkdguy]

The Sounds From Ganymede

[DShomshak]

The October, 2021 issue of Scientific American has a brief article that mentions a potential method of detecting life on exoplanets.

 

It starts with the fact that some molecules can occur in mirror-image forms. Many of the key molecules of Earthlife have this property -- and only use one version, not the other. "DNA molecules, for example, always have a 'right-handed' curl, while all known life uses only 'left handed' amino acids to build proteins."

 

When light reflects off molecules that are all of a given handedness, some of the light becomes circularly polarized: the light waves corkscrew, clockwise or counterclockwise. A new instrument called FlyPol uses this to assess the presence and health of life in an are: You fly the instrument over a region, it teases apart the light reflecting from below, and uses this to assess the density of plant life and even the health of the plants, from subtle details in the polarized portion of the light.

 

Here's the space bit: There is no intrinsic reason this could not be done over interstellar distances. The engineering is generations in the future, but scientists don't know of any process besides life that can generate complex, circularly polarized light signals. If you can find such a signal in the light reflecting off an exoplanet, there must be life with 'handed' biomolecules.

 

It is of course not certain that alien life would use 'handed' molecules. But at least there could be no false positives.

 

Dean Shomshak

[L. Marcus]

Handed, finned, tentacled ...

[DShomshak]

Heard on the news yesterday: JWST is five days out and unfolding on schedule.

 

Dean Shomshak

[DShomshak]

All Things Considered reports that the JWST's sunshield finished unfolding today. A project spokesperson praised the completion of this vital step in deploying the JWST, which he described as "The coolest thing in space." The sunshield is, of course, there to keep the spaceship at the necessarty low temperature to see in infrared. Is this NASA's version of a dad joke?

 

Dean Shomshak

[L. Marcus]

NASA doesn't do jokes, even if this makes it hard to explain Pete Conrad.

[Duke Bushido]

[rravenwood]

Darn it, Duke, now that music is going through my head...

[Cancer]

In the popular press, and in the tech journal this week, back in September they seem to have recorded a type II supernova (the core-collapse and explosion red giant sort) in the act.  The Astrophysical Journal link (it's all open access as of New Year's) is here, but that is the full-on technical paper.  I haven't had time to read more than the abstract and introduction, and probably won't until next week.

 

=================================================

 

 

On 1/4/2022 at 8:59 PM, DShomshak said:

All Things Considered reports that the JWST's sunshield finished unfolding today. A project spokesperson praised the completion of this vital step in deploying the JWST, which he described as "The coolest thing in space." The sunshield is, of course, there to keep the spaceship at the necessarty low temperature to see in infrared. Is this NASA's version of a dad joke?

 

Dean Shomshak

 

I think that level of humor was unintended.  JWST is definitely warmer than the microwave background, at bare minimum.