Science and technology benefit one another. New scientific theories afford new opportunities to create technology that can harness the laws of nature. Conversely, new technologies allow for better instrumentation and unprecedented efficiency in scientific progress. It’s a continual feedback loop, and some of the greatest challenges in science are solved simply by throwing more resources at them, or in other words, gathering more data. A good example of this is a relatively old problem for astronomers – determining how the spin of a galaxy affects it’s shape. We certainly don’t want for analogies on Earth, spinning pizza, driving on a...
Every time we see amazing photos of galaxies or planetary disks, we can see most of the detail since we see them face on. But since the orientation of spiral galaxies in the universe is random, there are a plethora of galaxies ignored by image processors since we just can’t see much of the detail. We can still learn from edge-on spiral galaxies, just not as much as we can from those that are face on. We can see some fascinating dust lanes in the image above, and a ton of detail considering the view, but we don’t know what...
Remember the big picture of Andromeda that showed 100 Million stars? That image resulted in a ton of new galaxy discoveries. Most of these new galaxies were once hidden beyond the Andromeda galaxy, but with the super high resolution image, astronomers and the public were able to look straight through and see far more distant objects. Most images of galaxies have what we call ‘field stars’ in them. These are some of the 400 Billion stars of the Milky Way that are far closer than the galaxy we are imaging. For this reason, galaxy images tend to look very cluttered...
They may look like they are standing still, but galaxies are all spinning. Spiral galaxies have the lovely regular spin of a disk, while elliptical galaxies are all over the place, a buzzing hive of stars. We don’t see this rotation in real time because it takes millions of years for it to be noticeable. The Milky Way takes 250 Million years to spin just once around it’s axis. Looking at this rotation rate vs. distance from the galactic center was what originally led to the discovery of dark matter. Some galaxies do in fact spin slower than others, but how does...
The Milky Way is a decently big Galaxy. At 100,000 light years across, it is a full size barred spiral galaxy and distinctly different from what we would call ‘dwarf galaxies.’ But there are much larger galaxies in the universe. Most reside near the centre of a massive galaxy cluster and are the result of Billions of years of mergers and collisions. But some appear large because of their incredibly powerful release of energy. A new Galaxy discovered in the early universe by a team of astronomers from the National Centre for Radio Astrophysics is an incredible 4 million light years...
Is this a giant hole in space? I show a picture similar to this as I ask this question to students and audiences that I host in my planetarium. Most people answer that it is a black hole, or dark matter, or dark energy, or something strange like that. But the amazing thing is that it is actually a thick cloud of dust that is opaque, letting no visible light from the distant stars pass through. The funny thing is that the cloud is transparent in infrared light, but in the visible spectrum it highlights something interesting about the universe:...
Maybe I am a starry-eyed dreamer, or maybe I just treat astronomy like a little kid opening birthday presents, but every time I see a new Hubble image I am blown away by it. Today’s mind-blowing photo is of Messier 63, the Sunflower Galaxy, located in Canes Venatici. It shows the central region of the galaxy and out tot he spiral arms. The arms are clearly visible due to the bright blue clusters of newly formed stars intermixed with dark patched of thick gas and dust. In between the arms lie older, redder stars. Closest to the centre, the yellowish...
Looking at the universe in different parts of the electromagnetic spectrum can reveal features and structures that are invisible to human eyes. The vast black emptiness of space explodes into a sea of colour when we use cameras to expand our vision. Looking at a galaxy through human eyes can be a simple and seemingly uninteresting view, but in infrared, microwave, or ultraviolet wavelengths we see the deeper layers of the vast array of stars. The closest large spiral galaxy and a cousin of our own Milky Way, the Andromeda galaxy, is revealed in ultraviolet. The Galaxy Evolution Explorer (GALEX)...
The Andromeda Galaxy is the closest large spiral to our own Milky Way, and the only major Galaxy moving toward us. Turns out its on a direct collision course, but we still have 3.5 Billion years to prepare, so its not exactly pressing news. On the plus side, studying Andromeda allows us to infer properties of more distant galaxies, and it gives us a map of what our own Milky Way Galaxy may look like. Astronomers using the Hubble Space Telescope have discovered a giant halo of gas around Andromeda, and the Milky Way may have a similar one. By...
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...
