Have you ever heard of an object called ‘Hanny’s Voorwerp?’ It’s a thin wispy ghost-like blob at the edge of a Galaxy. It was discovered by Dutch schoolteacher Hanny van Arkel in 2007 as she was classifying galaxies as part of the Galaxy Zoo project. Since then, astronomers have been studying its origin, as it was the first of a brand new phenomenon in astronomy. This past week, a new data set of wispy trails at the edge of Galaxies have been released as part of a Hubble study by Bill Keel of the University of Alabama, Tuscaloosa. The new Hubble...
We call it dark matter because it doesn’t give off light, right? Well there is a lot of matter than doesn’t radiate, but the difference is that whatever the stuff is that we call dark matter doesn’t interact with anything through the small-scale fundamental forces. The only way we have been able to detect it’s presence is through large-scale gravitational interaction. Dark matter is ‘dark’ because it doesn’t interact with anything in a way that lets us figure out what it’s made of. Well now that we’ve got that out of the way, we can look at the new...
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...
As the Dawn Spacecraft readies for orbit insertion only a week from now, the images coming in are getting sharper and sharper. Once the craft is fully in orbit its first task will be to map the surface of the planet in high definition. Even on the last few weeks of the journey to Ceres, we have seen increasingly clear images, and have already started asking ‘What the heck is that?’ This week’s ‘what the heck are we looking at?’ involves this apparent double bright spot on Ceres, imaged on February 19th from a distance of 46,000 Km, about an...
At one point in history, let’s say around 1994, astronomers were fairly confident in their understanding of the formation of planetary systems. Even though at the time we hadn’t found any planets orbiting other stars, they had long been theorized, and we figured that systems would form much like our own solar system. Rocky planets in the interior, gaseous giants further out, and a huge icy debris field at the outer edges. And then along came 51 Pegasi b. Half the mass of Jupiter, it orbits its star in only 4 days, far closer than Mercury. It was considered a...
With all the amazing Science coming from Mars in the last decade, its seems easy to conclude that humans have a good understanding of our rusty neighbour. And then something new and unexpected happens. To someone who thought we knew all there was to know, this may be a disappointment. But to a scientist who has a passion for discovery, new and unexpected results are where the biggest breakthroughs happen! Massive plumes have been spotted high in the atmosphere of Mars, at an altitude of over 250 Km, where the thin Martian atmosphere is nearly indistinguishable from the emptiness of...
Image submitted to an image processing competition called ‘Hubble’s Hidden Treasures’ are expected to be amazing, but this is the only one I’ve seen that will make you happier. This cosmic ‘smile’ is in the constellation Ursa Major, and is made up of the light from four galaxies, each with Billions of their own stars. This is the biggest happy face ever found! The two eyes are very distant galaxies known as SDSSCGB 8842.3 and SDSSCGB 8842.4. So why do we see this ring structure? You might think that the Galaxy is stretched by gravity, but its something much more...
There has been a lot to talk about with our home solar system lately. Spacecraft approaching dwarf planets, robots on Mars, and all kinds of orbiters giving new insights and views we had never expected. It’s a heavy news year for Planetary Science, and the great stories keep creeping up! Today we have an update on the Dawn spacecraft approaching Ceres. The picture I posted on January 20th (shown below) was from 380,000 Km away, comparable to the distance between Earth and the Moon. Now, about 2 weeks later, Dawn is only 145,000 Km away, and the view is much clearer!...
Being 2015, there has been a lot of talk about the New Horizons spacecraft in the first month of the year, since it’s due to reach it’s rendezvous with the enigmatic dwarf planet in July. I remember watching the launch in 2006 while in university, and have been talking about it to audiences during my planetarium shows. I feel close to the mission, and being able to see it reach Pluto this year brings back the first feelings I ever had about discovering the universe as a child. So when the spacecraft woke up a few weeks ago, so did...
Cassiopeia A is the expanding remainder of a massive star that exploded 340 years ago in he constellation of Cassiopeia (hence we call it Cas A for short). As the star erupted, hot radioactive material was shot out in all directions, churning up the surrounding outer debris, before the star finally tore itself apart. Simulations of supernova explosions have found it difficult to model the extreme conditions during this process, even when using the world’s best supercomputers. So what are astronomers missing? By studying recent supernovae like Cas A, astronomers can study the processes that formed these massive expanding shock waves, leading...
