A new atomic force microscope developed by MIT can scan images 2,000 times faster than existing commercial models. This allows it to capture near-real-time video of nanoscale processes.
State-of-the-art atomic force microscopes (AFMs) are designed to capture images of structures as small as a fraction of a nanometre – a million times smaller than the width of a human hair. In recent years, AFMs have produced desktop-worthy close-ups of atom-sized structures, from DNA strands to individual bonds changing between molecules. But scanning these images is a meticulous, time-consuming process. AFMs have therefore been used mostly for static samples as they are too slow to capture active, changing environments. Now engineers at MIT have designed an atomic force microscope that scans images 2,000 times faster than existing commercial models. With this new high-speed instrument, the team produced images of chemical processes taking place at the nanoscale, at a rate that is close to real-time video. In one demonstration of the instrument’s capabilities, the researchers scanned a 70- by-70-micron sample of calcite as it was first immersed in deionised water and later exposed to sulphuric acid. Zooming into an area of interest, they observed the acid eating away at the calcite, expanding existing nanometre-sized pits in the material that quickly merged and led to a layer-by-layer removal of calcite along the material’s crystal pattern, over a period of several seconds.
Calcite immersed in deionised water.
Sulphuric acid creating pits in the calcite.
Professor of Mechanical Engineering at MIT, Kamal Youcef-Toumi, says the instrument’s sensitivity and speed will enable scientists to watch atomic-sized processes play out as high-resolution “movies.” “People can see, for example, condensation, nucleation, dissolution, or deposition of material, and how these happen in real-time – things that people have never seen before,” he says. “This is fantastic to see these details emerging. And it will open great opportunities to explore all of this world that is at the nanoscale.” The MIT researchers' achievement was made possible through an innovative new technique. This involved controlling the movement of the needle over the sample surface with two actuators (a small, fast scanner and a larger, slower one) in combination with a set of algorithms to ensure they never interfered with each other. At present, this method provides scans at eight to 10 frames per second, but further research is underway to increase this. “We want to go to real video, which is at least 30 frames per second,” Youcef-Toumi says. “Hopefully we can work on improving the instrument and controls so that we can do video-rate imaging while maintaining its large range and keeping it user-friendly. That would be something great to see.” The team's design and images, which are based on the PhD work of Iman Bozchalooi – now a postdoc in the Department of Mechanical Engineering – appear in the journal Source: Article
Washington: The US space agency has successfully installed the first of 18 flight mirrors onto the James Webb Space Telescope, beginning a critical piece of the observatory's construction to replace the Hubble Space Telescope by 2018. After being pieced together, the 18 primary mirror segments will work together as one large 21.3-foot mirror. The full installation is expected to be complete early next year. "The James Webb Space Telescope will be the premier astronomical observatory of the next decade," said John Grunsfeld, astronaut and associate administrator of the Science Mission Directorate at NASA headquarters in Washington, DC, in a statement. This first-mirror installation milestone symbolises all the new and specialised technology that was developed to enable the observatory to study the first stars and galaxies, provide answers to the evolution of our own solar system and make the next big steps in the search for life beyond Earth on exoplanets. Several innovative technologies have been developed for the Webb Telescope that is targeted for launch in 2018. Webb will study every phase in the history of our universe, including the cosmos' first luminous glows, the formation of solar systems capable of supporting life on planets like Earth, and the evolution of our own solar system. The 18 separate segments unfold and adjust to shape after launch. The mirrors are made of ultra-lightweight beryllium chosen for its thermal and mechanical properties at cryogenic temperatures. Each segment also has a thin gold coating chosen for its ability to reflect infrared light. The telescope's biggest feature is a tennis court sized five-layer sunshield that attenuates heat from the sun more than a million times. The mirrors must remain precisely aligned in space in order for Webb to successfully carry out science investigations. While operating at extraordinarily cold temperatures, the backplane must not move more than 38 nanometers, approximately one thousandth the diameter of a human hair. — IANS. 
the size of Pluto. Unlike asteroids, KBOs have not been heated by the Sun, and are thought to represent a pristine, well preserved, deep-freeze sample of what the outer Solar System was like following its birth 4.6 billion years ago. The KBOs found in the Hubble data are thought to be the building blocks of dwarf planets such as Pluto. The New Horizons team started to look for suitable KBOs in 2011 using some of the largest ground-based telescopes on Earth. They found several dozen KBOs, but none were reachable within the fuel supply available aboard the New Horizons spacecraft. "We started to get worried that we could not find anything suitable – even with Hubble – but in the end, the space telescope came to the rescue," said team member John Spencer of SwRI. "There was a huge sigh of relief when we found suitable KBOs; we are 'over the moon' about this detection." 
