This tumblr's for all the great men and women of science for whom we owe our current understanding of the natural world; their achievements, their failures, and even their quirks, we celebrate them all.
For Science. For Inquiry. For Humanity.
“The surface of the Earth is the shore of the cosmic ocean. On this shore, we’ve learned most of what we know. Recently, we’ve waded a little way out, maybe ankle-deep, and the water seems inviting. Some part of our being knows this is where we came from. We long to return, and we can, because the cosmos is also within us. We’re made of star stuff. We are a way for the cosmos to know itself.”
― Carl Sagan, Cosmos
Reaction rate of many molecules depends on their shape
Artist’s concept of the sorting mechanism. Conformers with a larger dipole moment (marked blue) are deflected stronger than those with a smaller dipole moment (marked red). This way, one type of conformers can be picked and lead seperately to react with the ultra cool calcium ions. Credit: Yuan-Pin Chang/DESY
Most molecules occur in several shapes, which may behave very differently. Using a sorting machine for molecules, a German–Swiss research team can now for the first time directly measure the various reaction rates of different forms of the same compound. The team, led by DESY scientist Prof. Jochen Küpper from the Hamburg Center for Free-Electron Laser Science CFEL and Prof. Stefan Willitsch from the University of Basel, presents its work in the US journal Science. CFEL is a collaboration of DESY, the University of Hamburg and the Max Planck Society.
Many chemical compounds have numerous so-called conformers—different forms of a molecule in which some building blocks are spatially rearranged (rotated). “Even tiny changes in structure can greatly affect the properties of a compound,” says Küpper. “We want to know how exactly the molecular structure influences chemical reactions. Different conformers can even lead to different reaction products.”
To investigate these differences in more detail, the researchers have built a sorting machine for molecules, which can be used to selectively pick a conformer and feed it into a chemical reaction. The device exploits the fact that generally a change in structure also modifies the so-called dipole moment of a molecule. The dipole moment describes how a molecule interacts with an electric field. The sorting machine generates a non-uniform electric field between an electrically charged rod and a trough. When the researchers send several conformers at once through the narrow slit between the rod and the trough, the field deflects the various conformers to different degrees. The device thus provides sorted beams of different conformers, which can be spatially separated and directed individually into a reaction chamber.
As a test, the teams of Küpper and Willitsch sent two conformers of a well-known compound from the group of aminophenols through the device for sorting. Aminophenols are organic compounds that are used, among other things, for the production of medicines and dyes. The selected conformers differed only in the direction in which a single hydrogen atom is attached to an oxygen atom. “As a result, one conformer has a three times larger dipole moment than the other,” says Küpper.
The scientists directed the various sorted beams alternately into a so-called ion trap developed in Basel, in which the two conformers would react with electrically charged calcium atoms (calcium ions). “In the ion trap, the calcium ions are cooled to almost absolute zero at a temperature of minus 273 degrees Celsius. Doing so, they arrange themselves in space and form an ideal target for reactions with the spatially separated conformers,” says Willitsch.
"It turned out that one of the conformers has a reaction rate that is twice as high as that of the other," says team member Yuan-Pin Chang from CFEL. A tiny change in structure thus leads to big differences in chemical reactivity. "In this way, the method allows insights into fundamental reaction mechanisms that can lead to more effective syntheses of new molecules, such as active pharmaceutical ingredients," says Willitsch.
As a next step, the researchers want to improve the ion trap so that various ions and molecules could be used as reactants for sorted conformers. In addition, the trap will be combined with a mass spectrometer to determine the reaction products more accurately.
More information: ”Specific chemical reactivities of spatially separated 3-aminophenol conformers with cold Ca+ ions”; Yuan-Pin Chang, Karol D?ugo??cki, Jochen Küpper, Daniel Rösch, Dieter Wild, Stefan Willitsch; Science, 2013; DOI: 10.1126/science.1242271
Provided by Deutsches Elektronen-Synchrotron
Sounds like Oregon Trail was pretty spot-on when it came to causes of death. When Pa succumbed to the big D, the digital avatar was living the pain of tens of thousands of American pioneers.
There are two forms of dysentery. One is caused by a bacterium, the other, an amoeba. The former is the most common in Western Europe and the United States; and is typically spread through contaminated food and water.
Outbreaks of dysentery were more prevalent during war, where the disease spread rampantly because of the unhygienic conditions of the camps. During the Mexican War (1846-48), a staggering 88% of deaths were due to infectious disease, most of those overwhelmingly dysentery. For every man killed in battle, seven died of disease. The American Civil War was no better. You were more likely to die off the battlefield than on it, and dysentery was the primary cause. 
That said, civilians also died of dysentery with some frequency in the 19th century, especially those who were itinerant. Pioneers travelling the Oregon Trail wouldn’t have faired much better than soldiers fighting in war.
Read more about this microbial menace of yesteryear at thechirurgeonsapprentice.
Now about that whole caulk-the-wagon-ford-the-river thing …
After Chris Hadfield’s command of the International Space Station made him a global celebrity, it seemed only right to give him the rock-star treatment in our recent cover photo shoot.
Taking inspiration from Hadfield’s rendition of David Bowie’s Space Oddity, photographer Christopher Wahl asked the astronaut to replicate Bowie’s famed image from the cover of his Aladdin Sane album.
“He was fully participating—it was awesome,” says Wahl. “I was on a portrait high for a day and a half afterward.”
When glass breaks, the cracks move at around 3000 Miles per hour!! (4500km/h!) That’s why, even in slow motion, the main cracks in the glass appear virtually instantly as the hammer hits.
Columnist and presidential speechwriter Bill Safire was one of only three non-disloyal Jews President Nixon could name. Here is the speech he drafted for Nixon to read in case the Apollo 11 Astronauts became stranded on the moon.
This is chilling and SO interesting.
There’s a deceptively still body of water in Tanzania with a deadly secret—it turns any animal it touches to stone. The rare phenomenon is caused by the chemical makeup of the lake, but the petrified creatures it leaves behind are straight out of a horror film.
Lake Natron, a saline lake in northern Tanzania near the border with Kenya, is anything but paradise. In fact, most wildlife knows to avoid it because of how harsh conditions are there. The lake takes its name from natron, a naturally occurring compound made mainly of sodium carbonate, with a bit of baking soda (sodium bicarbonate) thrown in. Here, this has come from volcanic ash, accumulated from the Great Rift valley. Animals that become immersed in the water die and are calcified.
Have you heard of Lunar Analemma?
This digital composite image illustrates the changing position and phase of the Moon over the Dali Theater and Museum in Figueres, Spain, during one lunar month.
Analemma is generally known as the motion of the sun in the sky in a complete year. if you follow the position of the Sun at the same time each day, it makes an 8-like trace over the course of a year known as analemma. The position change is caused by the Earth’s motion around the Sun combined with the tilt of the Earth’s rotation axis (see 1, 2, 3). [**]
Analemma of The Moon by Juan Carlos Casado
Dear NASA, Happy Birthday! To Celebrate, We’re Shutting You Down. Love, Congress
55 years ago today, NASA was founded. Now, to celebrate, Congress has shut it down (along with the rest of the federal government). Just 549 of NASA’s 18,000+ employees are able to go to work, and those only because their jobs are so critical that there’s no choice (like keeping our astronauts alive on the ISS, little things like that).
Contrary to previous reports, though, the Curiosity rover will not be totally shut off during the shutdown, but JPL’s status will be reviewed on a week by week basis and NASA’s temporary closure means that not much Mars science is going to get done, or really any space science for that matter.
Sorry, NASA. Shitty birthday.
We’ll make it up to you.
Source: The Atlantic
Good morning! I flew F-18s, commanded ISS & lived on the ocean floor, but it all pales; I was a factoid on Jeopardy.