Thursday 17 January 2013

Curiosity's Tracks on Mars


The HiRISE camera on the Mars Reconnaissance Orbiter got this shot from orbit of the rover Curiosity's trek across Mars. This image shows the entire distance Curiosity travelled from the landing site (dark smudge at left) to its location as of 2 January 2013 (the rover is bright feature at right). The tracks are not seen where the rover has recently driven over the lighter-toned surface, which may be more indurated than the darker soil.




Full-size image & caption: http://www.uahirise.org/ESP_030168_1755

Saturday 12 January 2013

Largest Structure in Universe Discovered

The current view of the universe holds that space is homogeneous and isotropic at the very large scale. That is, it should look smooth and featureless, like a sponge, although at smaller scales it's made up of clumps, filaments and voids. For a long time, the largest known structure in the universe has been the Sloan Great Wall, a gigantic band of galaxies stretching 1.38 billion light years, and it was thought that no bigger structures could exist.

But now, the current model is challenged by an even larger structure.


 Light from the most distant quasar yet seen reveals details about the chemistry of the early universe.
CREDIT: ESO/M. Kornmesser

Astronomers have discovered the largest known structure in the universe, a clump of active galactic cores that stretches 4 billion light-years from end to end. The structure is a large quasar group (LQG), a collection of extremely luminous galactic nuclei powered by supermassive central black holes. This particular group is so large that it challenges modern cosmological theory, researchers said.

"While it is difficult to fathom the scale of this LQG, we can say quite definitely it is the largest structure ever seen in the entire universe," lead author Roger Clowes, of the University of Central Lancashire in England, said in a statement. "This is hugely exciting, not least because it runs counter to our current understanding of the scale of the universe."

The newly discovered LQC is so enormous, in fact, that theory predicts it shouldn't exist, researchers said. The quasar group appears to violate a widely accepted assumption known as the cosmological principle, which holds that the universe is essentially homogeneous when viewed at a sufficiently large scale. Calculations suggest that structures larger than about 1.2 billion light-years should not exist, researchers said.

"Our team has been looking at similar cases which add further weight to this challenge, and we will be continuing to investigate these fascinating phenomena," Clowes said.

Source:  Space.com

Wednesday 9 January 2013

The Vega System

A planet system around Vega? Very likely. Vega is one of the brightest stars in the northern sky, best visible in summer. And new evidence suggests it might have a system of planets just like our Sun does.

 This artist's concept illustrates an asteroid belt around the bright star Vega. Credit: NASA/JPL-Caltech
This artist's concept illustrates an asteroid belt around the bright star Vega. Credit: NASA/JPL-Caltech

Read more at: http://phys.org/news/2013-01-telescopes-evidence-asteroid-belt-vega.html#jCp

Astronomers have discovered what appears to be a large asteroid belt around Vega. The scientists used data from NASA's Spitzer Space Telescope and the European Space Agency's Herschel Space Observatory, in which NASA plays an important role.

The discovery of an asteroid belt-like band of debris around Vega makes the star similar to another observed star called Fomalhaut. The data are consistent with both stars having inner, warm belts and outer, cool belts separated by a gap. This architecture is similar to the asteroid and Kuiper belts in our own solar system. What is maintaining the gap between the warm and cool belts around Vega and Fomalhaut? The results strongly suggest the answer is multiple planets. Our solar system's asteroid belt, which lies between Mars and Jupiter, is maintained by the gravity of the terrestrial planets and the giant planets, and the outer Kuiper belt is sculpted by the giant planets.

Read more at: http://phys.org/news/2013-01-telescopes-evidence-asteroid-belt-vega.html#jCp
The discovery of an asteroid belt-like band of debris around Vega makes the star similar to another observed star called Fomalhaut. The data are consistent with both stars having inner, warm belts and outer, cool belts separated by a gap. This architecture is similar to the asteroid and Kuiper belts in our own solar system. What is maintaining the gap between the warm and cool belts around Vega and Fomalhaut? The results strongly suggest the answer is multiple planets. Our solar system's asteroid belt, which lies between Mars and Jupiter, is maintained by the gravity of the terrestrial planets and the giant planets, and the outer Kuiper belt is sculpted by the giant planets.

Read more at: http://phys.org/news/2013-01-telescopes-evidence-asteroid-belt-vega.html#jCp
The discovery of an asteroid belt-like band of debris around Vega makes the star similar to another observed star called Fomalhaut. The data are consistent with both stars having inner, warm belts and outer, cool belts separated by a gap. This architecture is similar to the asteroid and Kuiper belts in our own solar system. What is maintaining the gap between the warm and cool belts around Vega and Fomalhaut? The results strongly suggest the answer is multiple planets. Our solar system's asteroid belt, which lies between Mars and Jupiter, is maintained by the gravity of the terrestrial planets and the giant planets, and the outer Kuiper belt is sculpted by the giant planets.

Read more at: http://phys.org/news/2013-01-telescopes-evidence-asteroid-belt-vega.html#jCp
The discovery of an asteroid belt-like band of debris around Vega makes the star similar to another observed star called Fomalhaut. The data are consistent with both stars having inner, warm belts and outer, cool belts separated by a gap. This architecture is similar to the asteroid and Kuiper belts in our own solar system.

What is maintaining the gap between the warm and cool belts around Vega and Fomalhaut? The results strongly suggest the answer is multiple planets. Our solar system's asteroid belt, which lies between Mars and Jupiter, is maintained by the gravity of the terrestrial planets and the giant planets, and the outer Kuiper belt is sculpted by the giant planets.

 Source: http://phys.org/news/2013-01-telescopes-evidence-asteroid-belt-vega.html
Astronomers have discovered what appears to be a large asteroid belt around the star Vega, the second brightest star in northern night skies. The scientists used data from NASA's Spitzer Space Telescope and the European Space Agency's Herschel Space Observatory, in which NASA plays an important role.

Read more at: http://phys.org/news/2013-01-telescopes-evidence-asteroid-belt-vega.html#jCp
Astronomers have discovered what appears to be a large asteroid belt around the star Vega, the second brightest star in northern night skies. The scientists used data from NASA's Spitzer Space Telescope and the European Space Agency's Herschel Space Observatory, in which NASA plays an important role.

Read more at: http://phys.org/news/2013-01-telescopes-evidence-asteroid-belt-vega.html#jCp

Monday 7 January 2013

Dark Lightning Flings Antimatter Into Space

Researchers studying thunderstorms have made a surprising discovery: the lightning we see with our eyes has a dark competitor that discharges storm clouds and flings antimatter into space. Astrophysicists and meteorologists are scrambling to understand "dark lightning."

Bursts of antimatter create gamma rays which are detected by NASA's FERMI space telescope



I'm looking forward to more research into this phenomenon. I wonder if it's related to Sprites, Elves, and blue jets.

Friday 4 January 2013

The Beauty of Cosmos

The universe is an amazingly beautiful place. Although to the unaided eye it appears mostly black with a sprinkle of stars and perhaps a foggy band of the Milky Way, photography reveals the true colours and dynamics of space. The glowing clouds of gas, dark streaks of interstellar dust, cosmic landscapes sculpted by stellar wind and supernova shockwaves, all this and much more becomes visible thanks to modern technology.

One such beautiful vista is the nebula NGC 6188, featured in the Astronomy Picture of the Day for Dec 28 2012: http://apod.nasa.gov/apod/ap121228.html


This emission is found near the edge of a large molecular cloud unseen at visible wavelengths, in the southern constellation Ara. Massive, young stars were formed in that region only a few million years ago, sculpting the dark shapes and powering the nebular glow with stellar winds and intense ultraviolet radiation. The recent star formation itself was likely triggered by winds and supernova explosions, from previous generations of massive stars, that swept up and compressed the molecular gas.

Wednesday 2 January 2013

Colour of the Moon

Here's an interesting topic, the colour of the Moon. "What colour?" I might hear you ask. The Moon appears completely grey to us (not counting the times when it appears yellow / orange / red due to atmospheric effects or lunar eclipses).

In fact, there are subtle hues in the lunar surface, our eyes are just not that good at picking them. These subtle hues can be seen on some photographs of the Moon, the colours can be digitally enhanced, and you can even see subtle colouration when using binoculars or a telescope.

Two major colours that can be picked up are blue and rusty-brown. The blue is found mostly in the Sea of Tranquility and is caused by titanium-rich minerals. The rusty-brown is caused by iron-rich minerals.

Below are two photos of the Moon, one without any colour enhancement, and the other with enhanced colours:


Colour of the Moon is discussed in great detail in this article: http://www.colormoon.pt.to/
I also run a Facebook group dedicated to this topic: Colour of the Moon

Next time you look at the Moon through binoculars or a telescope, see if you can catch a hint of slate-blue colour in the Sea of Tranquility, it's the easiest to spot.

Tuesday 1 January 2013

Curiosity's Martian Holiday



NASA's rover Curiosity has been generating a lot of publicity as it traversed the martian terrain, performed studies, and sent back stunning colour images of that alien but very earthlike world. Now, as Mars moves to the opposite side of the Sun in its orbit, and communications with the rover will be made impossible for a while in April, the Curiosity team at JPL will be preparing the rover for its "holiday" by uploading software that will automate the rover for that period.


Curiosity's snaps of the martian landscape have captured attention of many people, not least for the fact that for the first time we see true-colour images and panoramas of Mars on a regular basis. Everything, from a small rock to a wide vista, is the subject of Curiosity's curious cameras.

NASA make most of the raw images received from Curiosity available at http://mars.jpl.nasa.gov/msl/multimedia/raw/  Some of those comprise a panorama, which can be assembled (or stitched together) using a software like Microsoft's ICE. You can find a few panoramas I created at www.facebook.com/CuriosityRoverPanoramas and there will be more panoramas coming as the rover travels to new locations and sends more images.