Some of the moons of gas giant planets have a unique property: They are worlds that have a source of heat other than the Sun. The huge tidal forces imparted by their host planet and fellow moons cause their crust to grow and shrink, creating huge friction and heating the rock. It means that even if these moons are far from the warmth of the Sun, they can still host liquid water. There are two moons in our own solar system that are especially enticing: Jupiter’s second moon Europa, and the icy moon of Saturn known as Enceladus. Each host...
The science of Astronomy goes far beyond what humans can see with our eyes. The visible part of the spectrum has taught us so much, but when we look at all photons across the spectrum of light, we find exponentially more powerful methods for discovering the mysteries of the universe. Radio waves, yes the same ones that bring you music in your car, are found throughout the universe in very interesting environments. Radio waves often trace the most powerful objects in the universe, such as super-massive black holes, quasars, and other types of active galactic nuclei. Humans see visible light...
Even I was blown away when I saw this image a friend sent me. Gravitational lensing is a rare occurrence, and a supernova is a rare occurrence, so to see a supernova in a gravitationally lensed galaxy deep within the universe is exceptional. So exceptional that it was spotted for the first time ever in a Hubble image of the distant universe. That dot in the image is a single supernova in a very distant galaxy, split into four images by the gravitational lensing of the galaxy cluster in front of it. But there is also a secondary lensing effect from...
I love to discuss Mars rovers. The thought of robots roaming around the empty red desert, doing science in pure form, unmasking the surprising history of our red neighbour, it’s exciting and it’s the frontier of discovery. The limits of science and engineering are pushed as we send complex machines to travel further than any human in history. But with such a marvellous feat, issues can arise, and when they do, the nearest mechanic is 55 Million Km away. On February 27th, during the transfer of a sample of dust from the rover’s drill to its instruments, the rover suffered...
1,200 Km / s. That’s fast. Fast enough to race around the entire Earth in 30 seconds. Except that it’s not a bullet, it’s a star, larger and more massive than the Earth. And a multinational team of astronomers has discovered it, and more importantly, where it came from and why it’s moving so fast. Hypervelocity stars (HVS’) are an uncommon phenomenon, since the conditions necessary to accelerate them to incredible speeds are rare. There are only about 20 HVS known, and the first was found only ten years ago. So where do they come from? There are only a...
Mars has water. This statement was in question 15 years ago, but now it’s an accepted idea backed up by proof obtained by the last three Mars rovers. Not only does Mars have water now, but it had significantly more water in the past, as evidenced by the geological features seen throughout the planet. Ancient lake and river beds, water erosion, sedimentary rocks, all things that highlight once wet areas. How much water did Mars have? Where did it all go? A team of astronomers from NASA’s Goddard Space Flight Center in Greenbelt, Maryland has been searching for answers, by looking...
Today is the day that the Dawn Mission completes a long 7.5 year long journey that has taken it past the orbit of Mars and into the asteroid belt, studying the second largest asteroid Vesta before heading toward the dwarf planet Ceres, where it has now injected itself into orbit, as of 7:39 am EST. This marks the first time in history a spacecraft has seen a dwarf planet up close, and with New Horizons passing Pluto in July, Dawn won the race in an astronomical photo finish. The Story So Far Launching on September 27th, 2007, Dawn orbited the Sun and...
With the MESSENGER probe set to crash into Mercury this month, it’s nice to look back on some of the finest data that it gathered during its tenure orbiting the smallest planet of the solar system. The image shows the Caloris Basin, the largest impact basin on Mercury and one of the largest in the solar system. The result of a massive asteroid impact during the early days of the solar system, the 1,500 Km wide crater was filled with lava aeons ago when Mercury was geologically active (seen in orange). Large impacts have punctured the surface of the basin since...
There is a loose hierarchy of the cosmos that repeats. Stars form clusters, and then galaxies. Galaxies form clusters, and then these form clusters of their own, called superclusters. Gravity dominates the structure of such collections, yet all we feel and see from Earth is a relatively homogeneous distribution of stars. How do we see this hierarchy? If we zoom in, looking at a patch of sky so tiny that we can’t see any stars, what do we see? This patch of sky is about the size of a grain of sand held at arm’s length, and if we point the...
Since the Huygens probe dropped down to the surface of Saturn’s largest moon Titan, astronomers have pondered the idea of life on the distant world. With a liquid cycle not unlike Earth’s water cycle in form, but consisting of frigid liquid hydrocarbons, could a new variation of life exist, not as we know it? Jonathan Lunine, director for Cornell’s Center for Radiophysics and Space Research, is an expert on Saturn’s Moons and is a scientist on the Cassini-Huygens mission, which originally discovered the Methane-Ethane lakes on Titan a decade ago. Given a grant to study non-aqueous life, he needed help....
