Science Sunday : “Lucky Imaging” - Sharpest pictures of Stars ever - even better than Hubble

Feast your eyes on this Cat’s Eye: Look at the clarity of the image!

Images from ground-based telescopes are generally blurred. There are techniques to reduce the blur (adaptive optics is one of them); now add another smart processing to the list.

The technique works by recording partially corrected adaptive optics images at high speed (20 frames per second or more). Software then checks each image to sort out which are the sharpest. Many are still significantly smeared by the atmosphere, but a small percentage of them are unaffected (sometimes a portion of the image might be unaffected).

These are combined to produce the final high-resolution image that astronomers want. The technique is called “Lucky Imaging” because it depends on the chance fluctuations in the atmosphere sorting themselves out and providing a set of images that is easier for the adaptive optics system to correct.

This work was carried out on the 200-inch (5.1 meter) Hale Telescope on Palomar Mountain. Like all other ground-based telescopes, the images it normally produces are typically 10 times less detailed than those of the Hubble Space Telescope.

Palomar’s adaptive-optics system produces superb images in the infrared, but until now, its images in visible light have remained markedly poorer than Hubble images. With the new Lucky Camera, astronomers were able to obtain images that are twice as sharp as those produced by the Hubble Space Telescope—a remarkable achievement.

The images produced in the study are the sharpest direct images ever taken in visible light either from the ground or from space.

In this image of the Cat’s Eye Nebula, one can resolve filaments that are only a few light-hours across! This is so amazing, we can see 3000 light years away and resolve things that are few light hours apart!

The full adaptive system will be ready in 2010 and I can’t wait to see some spectacular pictures.


Tags :


Science Sunday: Nano transistors, and does anyone have a Jive dictionary?

nano transistorWhen we heard about the phenomenon of “Self Excitation of Nano-Mechanical Pillars” and the possible implications in the development of nano-computing devices, we were as excited as the next “nanobods“. But what had us laughing off our chairs was the interpretation of the effect - if you could call it an interpretation - on the physics arXiv blog - in a southern Jive!

Convertin’ a constant force into an oscillatin’ one is a useful trick. Ya’ll seen em: gravity-powered pendulums and wind-powered turbines for example, them both set machines a-spinin and a-swingin by exploitin’ a constant force.

ImageThe science of the effect is the ability to convert a constant signal into an oscillating one - a visual example is the windmill where a constant force - the blowing wind - can set up a resonant oscillation frequency in the turbine.

This phenomenon of self excitation (SE) would be a very useful feature if it could be replicated within nano systems, since it can be produced by applying a constant DC voltage to produce an oscillation [At the basis of any kind of binary system, which will form the foundations of a computing system, is the ability to produce a varying or oscillating signal which can be ultimately be made to flip between two binary states on-off, 0/1 etc.].

ImageKim et all at UC Davis have published a paper describing the demonstration of self excitation in single electron, nano electro-mechanical transistors (NEMSET), which could form the basis for nano-computing systems.

Their device is a kinda nano-mushroom that stands between the plates of a capacitor, in a constant DC field.

Give the mushroom a push and it leans towards the source electrode where electrons tunnel across into the mushroom head. The DC field exerts a force on this extra charge on the ’shroom, pushing it towards the drain electrode where the electrons jump ship. The force disappears and the mushroom’s stiffness sends it swinging back to the source again like metronome, and the process starts again.

But back to jive - there is a neat website that lets you translate from English to Jive, but unfortunately not the other way around.

So the next time you write a boring article, you might want to spice it up with a double shot of Jive!

So de next time ya’ scribble some bo’in’ article, ya’ might wanna spice it down wid some double shot uh Jive. Right On!


Tags : ,


35 queries. 0.779 seconds.