Looking at the universe with human eyes is not always the best way to unveil its secrets and its beauty. Many pictures of remote astronomical objects we’ve grown so fond of use in fact false colours, as they were originally taken with cameras sensitive to different regions of the electromagnetic spectrum than those our eyes can see. Photographs of galaxies and nebulae are often used to study their full spectral emissions—well beyond the visible spectrum—, which provide useful information about the elements that make up these celestial bodies otherwise entirely out of our reach, and also about their temperature, density and many other features. Each region of the spectrum, corresponding to a different energy of the electromagnetic radiation that we can detect with our instruments, carries interesting information. Looking at radiation at 511 keV, which corresponds to the energy discharge produced by an electron meeting a positron (its antimatter twin) and annihilating each other, we get a very unusual picture of our galaxy. The image above shows what the universe would look like if all we could see were the gamma rays produced by an electron meeting a positron. The centre of our galaxy, in the middle of the image, appears to be a place of frequent matter-antimatter annihilations. The reason of this intense activity is still uncertain. Among the hypoteses considered by this extensive review available on the arXiv are the activity in the immediate surroundings of the black hole at the centre of the Milky Way and exotic dark-matter interactions.
Pop-upView Separately

Looking at the universe with human eyes is not always the best way to unveil its secrets and its beauty. Many pictures of remote astronomical objects we’ve grown so fond of use in fact false colours, as they were originally taken with cameras sensitive to different regions of the electromagnetic spectrum than those our eyes can see. Photographs of galaxies and nebulae are often used to study their full spectral emissions—well beyond the visible spectrum—, which provide useful information about the elements that make up these celestial bodies otherwise entirely out of our reach, and also about their temperature, density and many other features.

Each region of the spectrum, corresponding to a different energy of the electromagnetic radiation that we can detect with our instruments, carries interesting information. Looking at radiation at 511 keV, which corresponds to the energy discharge produced by an electron meeting a positron (its antimatter twin) and annihilating each other, we get a very unusual picture of our galaxy. The image above shows what the universe would look like if all we could see were the gamma rays produced by an electron meeting a positron. The centre of our galaxy, in the middle of the image, appears to be a place of frequent matter-antimatter annihilations. The reason of this intense activity is still uncertain. Among the hypoteses considered by this extensive review available on the arXiv are the activity in the immediate surroundings of the black hole at the centre of the Milky Way and exotic dark-matter interactions.

Source: sci.esa.int

“Life looks for life” is the second chapter of the Sagan Series collection, by Reid Gower. As with all the videos in this collection the narration comes from the legendary Carl Sagan, who finds a poetic perspective in all scientific frontiers and our place on Earth. The very existence of life is probably the most fascinating subject to consider when we look out to space and observe the vast potential of opportunities for other life forms, intelligent, curious, advanced or otherwise. 

The words of Carl Sagan really are timeless. This is the first in a collection of tribute videos dedicated to his scientific work as a cosmologist, astronomer, astrophysicist, and science communicator. Alongside inspirational narration from his 1980 TV series Cosmos: A Personal Voyage we are provided with impressive cinematography and a powerful soundtrack. Enjoy!

This video was taken from The Sagan Series, a project by Reid Gower.

We talked, not long ago, about how relatively rough simulations of the largest constituents of our universe can help us understand galaxy formation and evolution, how galaxies cluster together, and many other large-scale features of the known universe. But how do computer simulations incorporate things like dark matter and dark energy—which we know must be there and accounted for in our more and more accurate models, though we don’t quite know yet what they are? How can simulations be used as models of the observable universe, and provide testable insight? And how can we simulate the mutual interactions of billions of celestial objects, each attracting each other, and clustering and orbiting in many different ways, a problem mathematically unsolvable? An interesting article in the computing science section of the January-February issue of American Scientist offers an overview of the singular challenges associated with re-creating the universe in a box, and how this whole process represents a brilliant example of the scientific method in action in the digital era. Brian Hayes, “A Box of Universe”, American Scientist
Pop-upView Separately

We talked, not long ago, about how relatively rough simulations of the largest constituents of our universe can help us understand galaxy formation and evolution, how galaxies cluster together, and many other large-scale features of the known universe. But how do computer simulations incorporate things like dark matter and dark energy—which we know must be there and accounted for in our more and more accurate models, though we don’t quite know yet what they are? How can simulations be used as models of the observable universe, and provide testable insight? And how can we simulate the mutual interactions of billions of celestial objects, each attracting each other, and clustering and orbiting in many different ways, a problem mathematically unsolvable? An interesting article in the computing science section of the January-February issue of American Scientist offers an overview of the singular challenges associated with re-creating the universe in a box, and how this whole process represents a brilliant example of the scientific method in action in the digital era.

Brian Hayes, “A Box of Universe”, American Scientist

Since the creation of the internet and a colossal worldwide growth of personal computers, there has been a gradual change in the way some scientific research is carried out. Initially, idle computing power was donated by people wishing to contribute to science projects such as Einstein@Home, in order to perform computationally demanding tasks faster. However recently scientists have become just as interested in the brain power of people around the world to help them with ongoing science problems. Galaxy Zoo and the larger suite of Zooniverse projects have successfully built the largest (nearly 0.5 million) and most popular online community of ‘citizen scientists’ who are eager to participate in scientific projects. Citizen scientists have helped classify hundreds of thousands of galaxy images taken by NASA’s Hubble Space Telescope, as well as identifying a new type of greenish compact galaxies called Green Pea’s, which computer algorithms had previously been unable to spot, highlighting a key advantage for employing this type of analysis. The Milky Way Project is the ninth project to be contributed to by online citizen scientists, for which users are tasked with identifying bubbles of infrared emission in images taken by the Spitzer Space Telescope. These infrared bubbles are common features of regions of ionised gas and dust in the Milky Way and other galaxies that are undergoing star formation, which are of interest to astronomers. In a recent paper available on arXiv, it was shown that about 35,000 citizen scientists collectively found 5106 bubbles including at least 86% of objects already catalogued by experts, showing that the human eye and projects like this are an important tool for future astrophysics research.
Pop-upView Separately

Since the creation of the internet and a colossal worldwide growth of personal computers, there has been a gradual change in the way some scientific research is carried out. Initially, idle computing power was donated by people wishing to contribute to science projects such as Einstein@Home, in order to perform computationally demanding tasks faster. However recently scientists have become just as interested in the brain power of people around the world to help them with ongoing science problems. Galaxy Zoo and the larger suite of Zooniverse projects have successfully built the largest (nearly 0.5 million) and most popular online community of ‘citizen scientists’ who are eager to participate in scientific projects. Citizen scientists have helped classify hundreds of thousands of galaxy images taken by NASA’s Hubble Space Telescope, as well as identifying a new type of greenish compact galaxies called Green Pea’s, which computer algorithms had previously been unable to spot, highlighting a key advantage for employing this type of analysis.

The Milky Way Project is the ninth project to be contributed to by online citizen scientists, for which users are tasked with identifying bubbles of infrared emission in images taken by the Spitzer Space Telescope. These infrared bubbles are common features of regions of ionised gas and dust in the Milky Way and other galaxies that are undergoing star formation, which are of interest to astronomers. In a recent paper available on arXiv, it was shown that about 35,000 citizen scientists collectively found 5106 bubbles including at least 86% of objects already catalogued by experts, showing that the human eye and projects like this are an important tool for future astrophysics research.

Some objects are too big for us to interact with in any meaningful way. We often consider those things that are far too small to be seen or handled, but large objects can be just as problematic. Galaxies are so huge, as Professor Brian Cox never tires of reminding us, that even the idea of flying straight through one doesn’t really make much sense—unless you were a light particle, and even in that case you would be subjected to the gravitational pull of stars and it would take you a time much, much longer than our average lifespan to go from one side of the galaxy to the other. That’s where computer models come in handy. Even though they do not reproduce every tiny feature and local peculiarity of the known universe, they can be made to produce large collections of simulated space objects that collectively behave like—and hopefully provide some insight on—the real thing.