Could microbial life exist inside Enceladus, where no sunlight reaches, photosynthesis is impossible and no oxygen is available? The answer appears to be, yes, it could be possible.
I invite you to imagine the day when we might journey to the saturnian system and visit the Enceladus interplanetary geiser park, just because we can.
Saturn’s tiny, icy moon Enceladus has recently been visited by NASA’s Cassini orbiter on several very close approaches – once coming within a mere 25 kilometers of the surface. Scientists are learning a great deal about this curious little moon. Only 500 kilometers wide, it is very active, emitting internal heat, churning its surface, and – through cryovolcanism – ejecting masses of microscopic ice particles into Saturnian orbit. Cassini has been orbiting Saturn for over 4 years now, and has provided some amazing views of tiny Enceladus, some collected here.
Team members performed thermodynamic and kinetic modeling that simulates the geochemistry of phosphorus based on insights from Cassini about the ocean-seafloor system on Enceladus. They developed the most detailed geochemical model to date of how seafloor minerals dissolve into Enceladus’s ocean and predicted that phosphate minerals would be unusually soluble there.
“The underlying geochemistry has an elegant simplicity that makes the presence of dissolved phosphorus inevitable, reaching levels close to or even higher than those in modern Earth seawater. What this means for astrobiology is that we can be more confident than before that the ocean of Enceladus is habitable.”
Comverse has developed a version of the virtual world of Second Life that runs on a mobile phone. It sounds like the technology is imperfect at the moment (as is SL itself) and requires a PC to be running Second Life at an intermediary position, but it’s an interesting and potentially exciting step toward opening Second Life up to yet more uses.
Inertial electrostatic confinement fusion provides a potential breakthrough in designing and implementing practical fusion power plants. This is a $5T / year market. 2007-04-27: inertial confinement is a lot more promising than magnetic confinement. Plus 1000x cheaper to build. This is very very exciting (and a $5t/ year market). 2008-01-15: Fusion power grows more quickly than Moore’s law. It has increased by a factor of 10000 in the last 30 years, and another factor of 6 is required for a power plant. ITER will be 500MW, 10x over the energy threshold. 2011-08-03: Mark Suppes:
Science. It works, bitches. Mark Suppes is one of my heroes. He lives in Brooklyn. His hobby: building his own bussard fusion reactor. He will very likely fail, but what if he succeeds? Here is a nice article on him. If you are behind in your fusion terminology, bussard reactors are an alternative design that doesn’t require 10s of billions to get if off the ground. The best introduction is this tech talk:
2014-04-12: Since the big science / consortium approach hasn’t worked so far, maybe a macgyver approach will.
Ivanov’s story is just one example of the serendipity involved in this small Canadian company’s rise to the forefront of a worldwide race to harness nuclear fusion, a race that has been going on fitfully, consuming $10Bs, for more than 50 years. (All existing reactors operate using nuclear fission, rather than fusion, which is a very different process.) Started in 2002 by a successful corporate scientist in the throes of a midlife crisis, General Fusion has already outlasted past private-sector attempts to commercialize fusion energy. Instead of petering out, it’s garnered the attention and respect of a small but growing cadre of scientists, energy executives and adventurous investors around the world.
If LPP is successful with their research and then successful with commercialization they will achieve commercial nuclear fusion at the cost of $400K-1M for a 5 megawatt generator that would produce power for about 0.3 cents per kwh instead of 6 cents per kwh for coal and natural gas. It would be a game changer. Their monthly reports have shown that there are many technical, material and theoretical challenges. LPP has shown a lot of grit and ingenuity to overcome challenges.
The Experimental Advanced Superconducting Tokamak (EAST) in Heifi, China was able to sustain plasma in the H-mode confinement regime for 102 seconds.
2019-02-17: Fusion Projects Use Misleading Power Terms
ITER has spent over $14B so far and will only reach some level of plasma energy gain for a few minutes at a time if everything works as planned. The condition of Q = 1, when the power being released by the fusion reactions is equal to the required heating power is called breakeven or scientific breakeven. Plasma breakeven can be 100x away from what is needed for a practical reactor.
As explained by Sabine Hossenfelder:
The Q-plasma also doesn’t take into account that if you want to operate a power plant, the heat that is created by the plasma would still have to be converted into electric energy, and that can only be done with a limited efficiency, optimistically maybe 50%. As a consequence, the Q total is much lower than the Q plasma. If you didn’t know this, you’re not alone. I didn’t know this until a few years ago either. How can such a confusion even happen? I mean, this isn’t rocket science. The total energy that goes into the reactor is more than the energy that goes into the plasma. And yet, science writers and journalists constantly get this wrong. They get the most basic fact wrong on a matter that affects 10s of billions of research funding. The plan is that ITER will generate 500 MegaWatts of fusion power in heat. If we assume a 50% efficiency for converting this heat into electricity, ITER will produce about 250 MegaWatts of electric power. That gives us a Q total of about 0.57. That’s 6% of the normally stated Q plasma of 10. Even optimistically, ITER will still consume 2x the power it generates. What’s with the earlier claim of a Q of 0.67 for the JET experiment? Same thing.
The Reactor Core of Commonwealth Fusion Systems. This Tokamak plasma fusion ring supports the steepest temperature gradient in the solar system (1 million degrees to room temp within 2mm)!
This third party analysis verifies our investment thesis; tokamak fusion is an engineering project, not a science project. If they can build it, the scientific community agrees on the performance that will result.
The tritium used in fusion experiments like ITER, and the smaller JET tokamak in the UK, comes from a very specific type of nuclear fission reactor called a heavy-water moderated reactor. But many of these reactors are reaching the end of their working life, and there are fewer than 30 left in operation worldwide. 20 in Canada, 4 in South Korea, and 2 in Romania, each producing about 100 grams of tritium a year. But now, with the help of AI-controlled magnets to help confine the fusion reaction, and advances in materials science, some companies are exploring alternatives. TAE Technologies is attempting to build a fusion reactor that uses hydrogen and boron, which it says will be a cleaner and more practical alternative to D-T fusion. It’s aiming to reach a net energy gain—where a fusion reaction creates more power than it consumes—by 2025. Boron can be extracted from seawater by the metric ton, and it has the added benefit of not irradiating the machine as D-T fusion does. It’s a more commercially viable route to scalable fusion power. But the mainstream fusion community is still pinning its hopes on ITER, despite the potential supply problems for its key fuel. “Fusion is really, really difficult, and anything other than deuterium-tritium is going to be 100x more difficult, 100 years from now maybe we can talk about something else.”
To put things in perspective, shown data consists of the lead stories for each day of November 2004. New York was mentioned numerous times, and there was a story on Florida, hence the stretched area over US. Northern Europe was a source of several mentions also, hence the blip. Middle East was a heavy contributor and there were a couple of stories about Palestine, Sudan and Kenya, hence the stretched component over eastern Africa.
The discovery of suspicious objects on bridges, near a medical center, underneath an interstate, and in other crowded public places has ignited fears across Boston, snarling traffic and sending state and local police scrambling across the city.
this is what happens if headless chickens run the news.
2007-02-09: Do you have what it takes to save Boston from the Lite Bright menace?
2007-03-01:
if it’s not an american flag, it’s probably a bomb.
heh. i wonder what happens if someone wraps a bomb in a flag? will they declare a war on flags? that would actually be neat.
2013-03-31: reminds me of their war against things with LEDs from a few years back. among their bumbling peers, boston pd are the most incompetent. so funny.
Boston Punk Zombies Are Watching You! The Boston police go undercover on the Internet to stop the city’s most dreaded scourge: DIY indie-rock shows.
A mechanism for evolution where big chunks of DNA migrate between different species via bacteria. This results in faster and more sudden evolutionary branching than what you get with the more familiar mechanisms of sexual selection or random single-point
a massive network of recent gene exchange connecting bacteria from around the world: 10K unique genes flowing via HGT among 2235 bacterial genomes.
2008-10-05: The transfer can lead to recursive genomes
Scientists have discovered a copy of the entire genome of a bacterial parasite residing inside the genome of its host species. Lateral gene transfer may happen much more frequently between bacteria and multicellular organisms than scientists previously believed, with dramatic implications for evolution. This may allow species to acquire new genes and functions extremely quickly.
You can compare it to a bunch of bacteria which poke around a trash pile looking for fragments they can use. Occasionally they hit some ‘second-hand gold,’ which they can use right away. At other times they run the risk of cutting themselves up. There is potential risk when multi-resistant bacteria exchange small fragments of ‘dangerous’ DNA, e.g., at hospitals, in biological waste and in wastewater.
2021-06-09: It might even happen in animals, perhaps via sperm.
The barriers to horizontal transfer in eukaryotes looked insurmountable until the herring genome was published. The herring genome holds many copies of transposons, mobile chunks of DNA that can copy and paste themselves in a genome, but they are absent from other fish with 1 exception. 3 of them flank the rainbow smelt’s AFP gene, in the same order seen around the herring AFP gene. These sequences are “definitive proof” that a small chunk of a herring chromosome made its way into a smelt’s. 94% of the transfers involved ray-finned fishes; less than 3% involved birds or mammals. The explanation could hinge on herring’s famously exuberant spawning efforts. The vast majority of sperm fail to find eggs, degrade, and release their DNA. The DNA could stick to the gametes from other species spawning in the same area, and then get dragged into an egg cell during fertilization.
2021-10-21: It also happens in the human microbiome, which is less surprising since that’s just bacteria.
when humans started to colonize the island of japan 40 ka ago, they did not have the genes for digesting seaweed. Bacteria in the japanese gut borrowed the necessary genes from marine bacteria via horizontal gene transfer, and since the adaption proved evolutionarily beneficial, it was preserved. of course, anti-GMO nuts fear this horizontal gene transfer the most (if they are scientifically literate enough to understand the concept, and not just spout confused concepts like “natural” vs “artificial”). it should be quite obvious from this awesome example that mammals have had to cope with horizontal gene transfer throughout their history. GMO offers nothing new we haven’t encountered before.
2022-10-28: Transfer via viruses or parasites could explain how HGT happens between Eukaryotes.
The involvement of viruses could also help to solve another puzzle about horizontal transfers in eukaryotes. For the transfers to occur, the traveling genes need to clear an entire series of hurdles. First they must get from the donor species to the new host species. Then they must get into the nucleus and ensconce themselves in the host genome. But getting into the genome of just any cell won’t do: In multicellular creatures like frogs and herrings, a gene won’t be passed down to the animal’s offspring unless it can sneak into a germline cell — a sperm or an egg.
Is there something about the environment of Madagascar that makes it a hot spot for gene transfers? The abundance of parasites on the island might also be a contributing factor. Leeches may bring blood containing the snake’s jumping gene into the frogs, or perhaps the jumping gene is already in the leech’s own genome from previous contacts with snakes. Then maybe an unidentified virus does the rest.
The findings describe a new class of genetic agents involved in horizontal gene transfer, in which genetic information is passed directly between organisms — whether of the same or different species — through means other than lineal descent. The researchers have dubbed the agents that carry out this transfer “tycheposons,” which are sequences of DNA that can include several entire genes as well as surrounding sequences, and can spontaneously separate out from the surrounding DNA. Then, they can be transported to other organisms by one or another possible carrier system including tiny bubbles known as vesicles that cells can produce from their own membranes.
2023-08-04: Mavericks, or Polintons, are large DNA transposons that contain genes with homology to viral proteins. They are the largest and most complex DNA transposons known. Mavericks are one of the long-sought vectors of horizontal gene transfer. They are related to giant viruses and virophages.
Mavericks are an ancient and fragmented class of jumping genes prevalent in the genomes of protists, fungi and animals, including humans. These massive mobile elements were initially assumed to be inactive, mutated relics of obsolete genes. But later research revealed that Mavericks can be reactivated, and that they can mediate horizontal gene transfer between some species of protists. Complete, intact Mavericks had never been characterized in a multicellular organism.
The boards, which usually carry typical advertising, are programmed to identify approaching Mini drivers through a coded signal from a radio chip embedded in their key fob. The messages are personal, based on questionnaires that owners filled out.
i think this is super awesome. sure we will see new levels of spam, but showing up on the big screens in shinjuku would be too cool.
Gregor J. Rothfuss 