Let's just dive in... to the Sky!
The WFIRST project – now renamed the Nancy Roman Telescope – is a fantastic story. First, it’s built from a spare – obsolete – US spy satellite that uncannily resembles NASA’s venerable Hubble, donated by one of the intel agencies. (There are parts for one more, though that would be a slog. But I know what to do with it!)
The Roman will give us fantastic views of the universe in infrared. But this article shows how it may also vastly improve our knowledge of brown dwarfs and dark “planet-sized” objects in the nearby interstellar medium, detecting them by brief intervals – hours or days- making background stars flicker with gravitational lensing. (A bit like I described in EXISTENCE.) How wonderful that we are a people who can do such things! And did YOU feel an organic thrill when Persverance landed on Mars?
And how awful that so many of our neighbors turn their backs on science and the godlike trait of curiosity.
== Peering further into space ==
Astronomers examined the light from 43 quasars—the very distant, brilliant cores of active galaxies powered by black holes—located far beyond Andromeda. The quasars are scattered behind that neighbor galaxy, allowing scientists to probe multiple regions. Looking through Andromeda at the quasars’ light, the team observed differing effects caused by cold gas in immense halos surrounding our neighboring galaxy, revealing enrichment in heavy elements, presumably from earlier supernovas. It also gives you some idea how many quasars we’ve discovered, since those old debates between Halton Arp and Maarten Schmidt, at Caltech over what quasars were. I witnessed some!
Andromeda’s halo extends out 1.3 million light-years from the galaxy, almost halfway to our galaxy, and brushing (pushing?) against our galaxy’s halo.
In related news: A string of 13 dwarf galaxies in orbit around the massive galaxy Andromeda –remnants of the population of primordial structures that coalesced to form giant galaxies like the Milky Way–are spread across a flat plane more than one million light years wide and only 30,000 light years thick–a distance so vast that they have yet to complete a single orbit. Our galaxy seems to lack such a ring of companions.
Brian McConnell published his paper on the Interstellar Communication Relay this week, which can be found here.
And cool? This animation depicts a star experiencing spaghettification as it’s sucked in by a supermassive black hole during a ‘tidal disruption event’. Recently observed!
== Might an ever-expanding universe "renew"? ==
Have physicists discovered the remnants of previous universes hidden within the leftover radiation from the Big Bang? I’ve discussed with the brilliant Roger Penrose (Britain's most recent Nobelist and far more interesting than tabloid nobility) his cosmological theory called conformal cyclic cosmology (CCC) in which universes, much like human beings, come into existence, expand, and then “renew” themselves in a weird and wonderful way. (I contributed some very small insights!)
The notion is quirky and weird… and revives the symmetrical notion of a ‘cycling’ universe that restores itself to youthful vigor, without needing the Big Crunch that Frank Tipler relied upon in his baroque tome THE PHYSICS OF IMMORTALITY… a crunch that’s been disproved by astronomers discovering accelerated expansion.
In the Penrose conformal cosmology, the ultimate universal dissipation reaches a point where “distance” and “temperature” become meaningless and 'vastness' might -- just maybe -- map into a new Bang. It cannot happen till fermions dissipate... or at least lose their ability to 'know' where and when they are. That is a LONG way into the Great Dissipation! But in a universe rules by bosons (e.g. photons) it seems (so far) as if a cold-vast cosmos might map itself right back into another Big Bang!
If that isn't mind-blowing enough... there may be isolated spots where the old metric clings obstinately… perhaps where a final, ancient black hole is finishing its final, Hawking radiation dissipation, or else where a few residual fermions “insist” on their old individuality. (My contribution.) In which case the NEW Bang might contain patches where information survives from one universe to the next!
And so… are these shapes in the CMB telltales from such an earlier epoch? Or just eager shape recognition? And sure, I have a couple of short stories about just this. In my coming-soon Best-of collection!
== Life out there? ==
I’ve been in the “who's out there calculations” game since 1983. We sure know a lot more now. These astronomers now figure that G-type stars like our sun, which make up about 7% of the Milky Way’s approx.. 200 billion stars, likely on average have one Earthlike planet orbiting in a “goldilocks” (liquid water on the surface) zone about half of the time. "We estimate with 95% confidence that, on average, the nearest HZ planet around G and K dwarfs is ∼6 pc [parsecs] away, and there are ∼ 4 HZ rocky planets around G and K dwarfs within 10 pc of the sun."
“The new research did not consider red dwarfs, also known as M dwarfs, which make up about three-quarters of the Milky Way's stellar population. A 2013 study based on Kepler data estimated that about 6% of red-dwarf systems boast a roughly Earth-like planet in the habitable zone, and one such world is the closest alien world to our solar system, at a distance of merely 4.2 light-years — Proxima b, which orbits the red dwarf Proxima Centauri.”
What all of this leaves out is the most stunning discovery of the last 20 years to my mind… that our solar system doesn’t just have one “ice-roofed” ocean world – Europa – but as many as twelve! (By various definitions of ‘ocean’.) Which means just about every star out there might have some of those. Not just in 'habitable zones' or near stable stars but almost ALL of them!
Exoplanet K2-141b is about half again as big as Earth, so close to its M class star, that it completes several orbits each Earth-day with the same surface permanently facing the star. ‘Now, scientists predict those factors mean that two-thirds of the surface of K2-141b is permanently sunlit — so much so that not only is part of the world covered in a lava ocean, but some of that rock may even evaporate away into the atmosphere.’ One has to wonder if such churn might create some mineral states that, like bio cell walls in our early seas, allow accumulation of complexity.
This series of Fermi Paradox papers: (especially #XII) explores the “Water Worlds hypothesis.” And yes, my 1983 paper pioneered much of this.
== A SETI/METI compromise? ==
Been reading the July 2020 special issue of the Journal of the British Interplanetary Society’s issue on the Search for Extraterrestrial Intelligence (SETI) and especially the arguments (I’ve been deeply involved) over whether humanity should risk transmissions that shout ‘yoohoo!” into the cosmos, a rash and pseudo-religious program oft-called “METI." Of special interest is ‘Reworking the SETI paradox: METI’s Place on the Continuum of Astrobiological Signaling’ by
Thomas Cortellesi .
As for the summary of Meti pro/cons made by Cortellesi, while incomplete and a bit chaotic, it is pretty good, but it leaves out one of the most devastating challenges to METI. METI zealots assert that relatively nearby aliens -
(1) can easily detect Earth’s comms leakage or other tech-signs, and further they
(2) would contact us, but only if they receive a deliberately assertive first move on our parts.
While this pair of linked assertions is not impossible, #2 is based upon a strange (even illogical) assumption: that the younger and more technologically backward civilization - facing the widest range of potentially dangerous uncertainties - should bear the onus and risk of initiating contact. That contorted logic, alone, would discredit the notion. But there is a deeper, more devastating question. If advanced aliens can easily detect Earth’s comms leakage, but are waiting for us to move first then why do the Metists insist on transmitting in ways that multiply the at-target brightness of Earth’s tech-signatures by many millions-fold?
Since the ETs already know of us, would not a signal with just twice the at-target brightness and clarity be more than sufficient to trigger their supposed contact scenario? Are not efforts to multiply detectability many millions-fold a refutation of belief in assumption #1?
(And in fact, #1 is just flat-out wrong! ET is not watching "Mr. Ed.")
While this question devastates a core METI argument, it also opens a door for something missing, so far… a negotiated solution. A potential compromise.
*Let Meti guys send their ‘messages,’ but monitored and supervised never to exceed in power, detectability or decipherability twice the magnitude that Earth’s current leakage would create, at the same site.*
In this way, the claim that benevolent aliens already know of us and are awaiting our first move can be tested, but in a way that stands little likelihood of alerting those who are unaware of us, giving humanity time to better understand the galactic 'lay of the land' - especially whether darker scenarios might reign out there.

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