Daily Archives: January 11, 2008

New Twist in microRNA biology

MIT scientists have found a new way that DNA can carry out its work that is about as surprising as discovering that a mold used to cast a metal tool can also serve as a tool itself, with two complementary shapes each showing distinct functional roles.Professor Manolis Kellis and postdoctoral research fellow Alexander Stark report in the Jan. 1 issue of the journal Genes & Development that in certain DNA sequences, both strands of a DNA segment can perform useful functions, each encoding a distinct molecule that helps control cell functions.

There is a full press report here.

Unexpected Black Holes

This just in from the Jet Propulsion Laboratory:

NASA’s Spitzer Space Telescope has detected plump black holes where least expected — skinny galaxies….Scientists have long held that all galaxies except the slender, bulgeless spirals harbor supermassive black holes at their cores. Furthermore, bulges were thought to be required for black holes to grow.The new Spitzer observations throw this theory into question. The infrared telescope surveyed 32 flat and bulgeless galaxies and detected monstrous black holes lurking in the bellies of seven of them. The results imply that galaxy bulges are not necessary for black hole growth; instead … dark matter could play a role.”This finding challenges the current paradigm. The fact that galaxies without bulges have black holes means that the bulges cannot be the determining factor, ” said Shobita Satyapal of the George Mason University, Fairfax, Va. “It’s possible that the dark matter that fills the halos around galaxies plays an important role in the early development of supermassive black holes.”…

Read the whole story here. http://www.spitzer.caltech.edu/Media/releases/ssc2008-01/release.shtml

Interplanetary collision called off

An asteroid heading for Mars is going to miss the angry red planet. Too bad, that would have been cool.But there is a very cool graphic that results from the science surrounding this non event.This is a moving GIF showing the evolution over time of the uncertainty region for the collision. You can see where mars was initially in the uncertainty region, and over time, as the uncertainty region became smaller and smaller, the planet moved first to the edge then entirely out of the region.Much like Barack Obama and the New Hampshire Primary.Oh well, maybe next time. Mars and Barack.The full story and more graphics are here.