Space soufflé

Outer space...is a vast slow cooker. The densest interstellar gas may contain 10,000 hydrogen atoms in a cubic centimeter, and three or four carbon atoms. This is a thousand trillionth of the density of the air we breathe. An atom in deep space may travel 100,000 kilometers before bumping into a partner. 

But... a long underappreciated bevy of three protons and two electrons called protonated molecular hydrogen, or H3+, catalyzes a great network of reactions as elements collide, or stick to the surface of star-produced microscopic silicate and carbon dust grains. Over many millions of years, compounds as complex as polycyclic aromatic hydrocarbons are manufactured, with dozens of carbon atoms in arrays of benzene rings. Other structures are precursors to amino acids...

Goodbye Copernicus, Hello Universe by Caleb Scharf.

See also Deep Space, Branching Molecules, and Life’s Origins?


Image: Ben McCall

Hadean

The collision of a 500km diameter body with the Earth results in a cataclysm almost unimaginable. Huge regions of the Earth's rocky surface would have been vaporised, creating a cloud of super-heated 'rock-gas', or vapors several thousand degrees in temperature. It is this vapor, in the atmosphere, which causes the entire ocean to evaporate into steam, boiling away to leave a [layer] of molten salt on the seafloor. Cooling by radiation into space would take place, but a new ocean would not rain out for at least several thousand years after the event. Such large, Texas-sized asteroids or comets could evaporate a ten thousand foot deep ocean, sterilising the surface of the Earth in the process.

from A New History of Life by Peter Ward and Joe Kirschvink (2015)

Image via Daily Galaxy

Blazing heart

The fact that fusion can occur in [stars] is in many ways astounding. Fusion is not simply a union of two nuclei. In most stars, hydrogen nuclei can’t get close enough to fuse. The closer a pair of hydrogen nuclei get, the more strongly their positive charges push them apart. But because nuclei are quantum objects, they don’t need to be close enough to fuse, just to be in the same ballpark. From there an effect known as quantum tunneling can do the rest. One moment the two nuclei are almost close enough to fuse, and the next moment they suddenly find themselves bonded together. It is as if the nuclei don’t have enough energy to open the door and walk through, but they occasionally will teleport through walls. 

But even this bit of quantum magic isn’t enough for a star to succeed. Not only does fusion have to occur, it has to produce something stable. When two protons fuse to become helium-2 (containing two protons and no neutrons), it is extremely unstable and usually splits right back into two separate protons. But there is a 1 in 10,000 chance that one of the protons will instead transform into a neutron, and the atom then becomes deuterium, a stable isotope of hydrogen. Deuterium and hydrogen can fuse to make a stable helium, releasing a huge amount of energy and opening up the amazing creative potential of stars.

— from How the universe made the stuff that made us by Brian Koberlein

Image: anonymous portrait of young Romanian girl (via Jane Long)

There never was more inception than there is now

Emergent phenomena remain elusive — exceedingly difficult to predict from observations of earlier stages. Given hydrogen atoms, a tremendous conceptual leap is required to predict the brilliance of stars or the variety of planets. Given planets, no theoretician alive could predict the emergence of cellular life in all its diversity — nor, given cellular life, could anyone foresee the emergence of consciousness and self-awareness...

We are left, then, to ponder the possible existence of higher orders of emergence — stages of complexity that our brains can no more comprehend than a single neuron can comprehend the collective state of consciousness. Does the universe hold levels of emergence beyond individual consciousness, beyond the collective accomplishment of human societies? Might the cooperative awareness of billions of humans ultimately give rise to new collective phenomena as yet unimagined?

— from Genesis: the Scientific Quest for Life's Origins by Robert Hazen (2005)


The title of the post from Song of Myself  by Walt Whitman (1855)

Image: Two pyramidal neurons by Gregory Dunn (2009). See also works by Ramón y Cajal such as this (1899)

"She tosses her creatures out of nothingness..."

Research into the origin of life benefits from thinking about whole planets, says Andy Knoll:

Planetary history is the context for thinking about the history of life on a planet. When we explore Mars, it's our experience on Earth that informs that exploration. When Dimitar Sasselov, Dave Charbonneau and Dave Latham give us a sense of planetary atmospheres from Kepler, it will be our understanding of relationships between life and environment that will inform our interpretation of those atmospheres. It's hard for me to imagine efforts to understand either the origin of life on this planet or the distribution of life through the universe that don't revolve around the nature of planets.

as well as specific conditions on those planets:

Life was probably born in a small pond or lake, Jack Szostak believes...Rain-fed pools provide a fresh water environment, compatible with the delicate cell membranes formed from simple fatty acids, which would be destroyed instantly in the salty oceans. Some such pond was the place where crucial elements were mixed, heated and cooled in the right sequence to become life. Inanimate molecules, congregated together inside a fatty skin, somehow became capable of replication, and of evolution: the definition of life, as Szostak sees it. 

Very likely, Szostak says, life began near a hydrothermal vent: an underwater spout of hot water, flowing into the cold water of an icy lake, much like modern Yellowstone Lake in winter. This, he believes, was the oven and freezer where the ingredients of life were cooked, cooled, thawed in the order required for nucleic acids to go through cycles of replication, and for fatty acid membranes to allow nutrients to enter into the cell.

The quote at the top of the post is from one of Goethe's aphorisms on nature as cited by T. H. Huxley.

Image: Baobab trees on a mushroom island in Bay of Moramba, Madagascar, by Sebastião Salgado

Ribosome

The ribosome is a tiny organelle present in all living cells in thousands of copies that manufactures the protein molecules on which all life is based. It effectively operates as a highly organized and intricate miniature factory, churning out those proteins – long chain-like molecules – by stitching together a hundred or more amino acid molecules in just the right order, and all within a few seconds. And this exquisitely efficient entity is contained within a complex chemical structure that is some 20-30 nanometres in diameter – just 2-3 millionths of a centimetre.

-- from What is Life? by Addy Pross

Added 27 October 2014: Listen to this section of Radiolab's translation show.

Added 26 Jan 2015: "We are all just different kinds of homes to the ribosomes!"


Image: David S. Goodsell, the Scripps Research Institute via RSBC Protein Data Bank