Researchers at NASA’s Jet Propulsion Laboratory recently reported the detection of water and methane, a simple organic molecule, a distant planet outside of our solar system.  This finding is exciting to scientists because it confirms that organic molecules and water – two potential building blocks of life – can be identified on distant planets.

The planet, known in astronomy circles as HD189733b, orbits a star slightly smaller than our Sun.  It is located a long ways from earth – 369 trillion miles (63 light years), to be exact.  It’s surface temperature is ~ 1,700 degrees Fahrenheit, far too hot to support life as we know it.  Therefore, the detection of methane and water on HD189733b is more proof of principle, rather than a hot lead for life.  

Data were collected using the Hubble Space Telescope.  Researchers measured light originating from the planet’s star that had passed through the planetary atmosphere.  The properties of light passing through a planetary atmosphere are are altered slightly by the the types of molecules found therein.  A full description of the method can be found in an NPR interview with NASA scientist Mark Swain.

The ability to conduct these types of measurements opens the door to similar studies of other planets whose surface temperature might be more like our own.  

The Jet Propulsion Laboratory website has nice collection of audio and video features, including a clip on the search for life on other planets.  

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An article in the New York Times this week explores the much-covered topic of performance enhancing drugs. This time, however, the users are not athletes, and the goal isn’t more home runs.

Instead, as reported in the journal Nature, prescription drugs such as Adderall, used to treat attention deficit disorder, and Provigil, used to treat narcolepsy, are being taken by college students and faculty alike to increase academic performance through enhanced concentration and wakefulness. 

Opinions on the ethical issues surrounding “brain-boosting” differ, especially between those who use the drugs and the experts who speculate on the long term consequences. Some urge that widespread use will eventually raise “normal” standards, creating an unfair advantage for those with access to the drugs over those who do not. Others suggest that making people who are already driven and productive even more productive could be seen as a positive thing, assuming- and this is a big assumption- that no one, including the user, is harmed in the process. 

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The earth has approximately seven and a half billion years left to live, according to mathematical models made by researchers at University of Guanajuato in Mexico and the University of Sussex in England.

The earth’s demise is being driven by an aging sun, which is actually becoming larger, brighter, and warmer with age.  In fact, life on earth may end well before the 7.5 billion year estimate, when the earth will be engulfed by the sun.  Researchers speculate that one billion years from now, the temperature of earth will have risen to the point where the oceans boil off, effectively ending life on earth.

Although this news sounds  rather bleak, it’s worth noting that estimates of the earliest, single-celled life forms on earth are in the 3 billion-year-old range.  We definitely have some time to explore other solar systems….

Original Article

In all fields of science, researchers rely on mathematical models to make predictions about future events (will an asteroid hit earth?), predict how a system might react if perturbed, (does an excess of carbon dioxide in the atmosphere lead to global warming?), and even to investigate why a process works the way it does (how do neurons in our brain communicate with each other?).

In a recent issue of the journal Nature, University of Wisconsin researchers report that they have developed a mathematical model to examine the behavior of a complex lake ecosystem involving fish, insects, and hard-shelled algae known as diatoms. The model was developed using data from an Iceland lake whose fish population declined rapidly in over the last 25 years.  The model suggests that the lake’s insect population is extremely sensitive to changes in the ecosystem, and that the observed crash in fish population may have been caused by human activity.

The explanation goes like this: lake dredging led to subtle changes in the diatoms’ ecosystem that in turn resulted in profound changes in the lake’s food chain. Dredging changed the algae’s distribution in the lake, which led to fewer algae for insects to eat, which lead to fewer insects for the fish to eat.  In a normal ecosystem, the population of insects normally rises and falls over a regular, predictable interval.  But in this instance, the interval is irregular. This may explain why the fish population collapsed.

Most importantly, this research reinforces the sensitivity of natural ecosystems to seemingly small natural and/or man-made changes.

Original Article

Following up on a news item we reported in February (My Cortex Made Me Buy It), a recent medical study adds credence to the misplaced notion that expensive = effective.

Researchers asked study participants to rate the effectiveness of two pills allegedly designed to provide pain relief.  The subjects were told that one pill cost $2.50, while the other pill cost $0.10. Each subject was given a small electrical shock and asked to rate the effectiveness of each pill.  In truth, both pills were placebos (sugar pills).

For both pills, subjects perceived significant pain relief (a placebo effect). But with the $2.50 pill, perceived pain relief was 24 percentage points higher than for the $0.10 pill.

Let’s hope this doesn’t give pharma companies justification to raise prices…

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