It’s not only the beginning of the week, but also the first day of February, with Spring creeping up slowly upon us. No snow is predicted in Chicago this week, so we’ve had a very warm winter— thanks to China and the Koch brothers. On this day in history, Russia adopted the Gregorian calendar in 1918, the first sit-in by black students took place in Greensboro, North Carolina in 1960, the Beatles had their first U.S. number one hit (“I Want to Hold your Hand”) in 1964, a song I well remember when it came out, the Ayatollah Khomeini returned to Iran in 1979, and, in 2003, the space shuttle Columbia disintegrated upon re-entry, killing all seven astronauts, but leaving alive a culture dish full of Caenorhabditis elegans. On February 1, 1937, both Don Everly and Garrett Morris were born; and, on this day Mary Shelley died in 1851, Piet Mondrian in 1944, and Buster Keaton in 1966. It is the beginning of Black History Month, LGBT History Month, and National Bird-Feeding Month (can we add squirrels there?). Meanwhile in Dobrzyn, someone should tell Hili that the next step is a doozy:
A: What are you thinking about?
Hili: About my next step.
Ja: Nad czym myślisz?
Hili: Nad następnym krokiem.
A treat, courtesy of reader Don B. Shake your head from side to side while looking at this, and, with luck you’ll see a ____. I have no idea why it works.
No need (for me) to shake. I just back away with my myopic vision until the screen is no longer in my focal plain.
Ha ha, “back away”. I just take off my glasses that I wear in the morning but then the image is a bit blurry.
Same here, for the same reason. However, if I get the screen within my focal plain the ____ disappears. Shaking my head does not make it reappear. Most peculiar.
I believe the above graphic incorporates a low contrast slightly blurred image of the ___; while the sharp, high contrast lines dominates the vision of the normally sighted. The appearance of the ___ on movement being due to persistence of vision.
Just raised my glasses
My left eye is short sighted, the right one is long sighted. Only way I can make it disappear is to use my laptop, close one eye and move either closer or further away, depending on which eye I choose, (on my phone it’s always there, no matter what).
What an amazing story behind your comment about C elegans! See here for more details:
http://www.cmu.edu/magazine/03fall/wormsurvive.html
This seems to show that interplanetary transfer of life is a real possibility.
Yep, those C elegans came from a lab that was down the hall from mine at Pitt. My understanding is that they were in an extremely well padded container, tho, so I think concluding the possibility of interplanetary transfer of life from this is another thing.
According to the press, the authors of the papers on the worms did conclude that this showed interplanetary transfer of life was not as improbable as some had argued.
“From an astrobiology standpoint, the important thing was that if you had a multicellular organism going through the atmosphere you can have interplanetary transfer of life by natural means, and Columbia demonstrated that,” Szewczyk said.
Spore making prokaryotes, perhaps. The minimum travel time between Earth and Mars has been estimated to a year for ejecta.
Though nematodes are tough. They have found new species at high temperatures and pressures in fissures down to 1 km (IIRC).
Yes, scientists are slowly uncovering a rich, deep extremophile biome, whose members may be especially resistant to some of the conditions experienced by large ejecta of meteor impacts. There might easily be enough material in these to provide the same degree of thermal insulation as was provided by the little foam pads around the petri dishes of these nematodes. So the tail end of the journey might not be fatal, though a year or two spent in vacuo might weed out most things…
Surviving ejection is one matter – which is heavily dependent on the escape speed of the body you’re trying to leave. Then you have to survive the flight phase – Torbjorn’s year is an extremely optimistic combination of trajectory and velocity which gets very close to an optimal Hohmann transfer orbit (without a detour to 1996 FU13 – Asteroid Hohmann) ; less unlikely transfers take thousands to tens of thousands of years, which the transferred organisms would have to survive with fairly minimal radiation shielding (I’m not bothering about non-lethal mutations – to misquote Cromwell, “Mutate them all ; let Darwin sort them out!”). Remember that over your head there is approximately the equivalent of some 4 metres of rock shielding you from cosmic rays and solar UV. Then you need to land your organisms without incinerating them.
I’m not going to fall into the ACClark Trap and claim that it’s impossible. But the challenges in successfully transferring organisms from one planet to another are not much slighter than those of generating life on your own planet. Anyone who thinks “abiogenesis is too difficult ; I’ll believe in panspermia instead” is neglecting that fact that you implicitly have to deal with both panspermia (not an easy option) and abiogenesis at your source planet. And now you don’t even know where the abiogenesis is required to take place. It’s not an “easy out“.
Yes, as I said, the vacuum is the challenge, and your point about the likely timespan is a good one. But radiation may not be as important as you suggest; an ejectum big enough to survive the trip will probably be thick enough to be a good shield. It would probably break up during re-entry as these things tend to do, and then fall pretty much like the C elegans cultures fell, though probably with a higher terminal velocity.
Sure, panspermia is not an “easy out”, but it does expand the universe of possibilities in interesting ways, and may provide an easier path to life on some of the more extreme planets. It’s an interesting thing to keep in mind, especially if some day life turns up on Mars.
Cebra.
The current warmer than average winter is actually thanks to a very strong el Nino system in 2015 that is only now beginning to fade.
Yes, and here in Minnesota, I am loving it!
…AND global warming.
With my eyeglasses (corrected for near-sightedness and astigmatism) I don’t see a darn thing when I shake my head. I took my glasses off & voila! There is the image.
Same here, shaking head didn’t work, doing my best with defocusing worked (barely).
I see a ____, but it’s not just any ____ – it’s ‘Business ____’.
All I see is the Newcastle United top.
I see it both when I shake my head and if I just slightly defocus. If a defocus a lot, it goes. Ugh, giving myself a headache!
Shaking or removing glasses. Both work; though on this Monday morning removing the glasses is easier on the brain.
Standing back without my glasses reveals a somewhat coloured image. The two pink parts near the top are the most noticeably coloured.
Some of the image information is hidden in the subtle tinting and shading of the pale stripes and some in the width of the dark ones.