Nebula. Collapse. Protostar. Main Sequence. Red Giant. Planetary Nebula. White Dwarf. This is the cycle of life for a star like our Sun. By observing stars across the galaxy, we see snapshots of different points in a star’s life cycle. It’s the same with people; If you went for a walk in a city and observed people for a day, you would see every single stage of a person’s life: Infant, child, adolescent, youth, adult, middle aged, senior. How would you put them in order if you knew nothing about them? With people you might go up and ask them, but with stars we can...
Our planet orbits the Sun. 365.25 days to go full circle (ellipse actually) and bring the seasons to Earth. But the Sun is not really stationary, it’s actually moving through space. It’s orbiting the center of the Milky Way, along with the rest of the galaxy. It actually has a periodic motion as it moves around the Galaxy, slowly moving up above the galactic plane then being pulled back down below by the disk stars. Currently, the Sun is moving toward the constellation Hercules at a speed of around 72,000 Km/h. It is also moving up to the top of the...
Let me ask you, when you look at the stars on a cold, clear night, what do you see? Diamonds sparkling? Shapes? I do see those things, but I also see so much more. When I look at the stars, I see a thousand generations of humans looking up in wonder, writing shapes in the dirt and telling incredible stories of brave heroes, ferocious beasts, and important lessons. I see our common ancestors using the sky to predict the weather, the seasons, and even the coming of the end of the world. They were looking at a comet in the...
If you look up into the sky on a clear night, you would see thousands of stars. There are surely many more that you would need a telescope to see. But there are not stars everywhere. You can zoom in further and further with bigger and bigger telescopes, until eventually you find gaps where you simply don’t see stars. For a long time it was thought that the gaps were empty, until the Hubble telescope peered through the darkness by taking a 200 hour exposure of a supposedly empty patch of sky. What it revealed was a universe full of...
After focussing all of its energy on taking science data during closest approach, New Horizons has been slowly but surely sending back the stream of information collected on the Pluto system. This long process of returning the data to Earth has meant periodic updates for humanity, and a rekindling of excitement for the newest secrets revealed about the dwarf planet. Here is a video of the region of Pluto imaged in high resolution, followed by some of the best still along the way. This is the closest and most detailed view of Pluto that humanity will have for decades. We...
Massive stars and low-mass stars live different lives. They are born in different environments, fuse different elements during the course of their lives, release different amounts of radiation across the electromagnetic spectrum, die in different ways, and enrich interstellar space with different metals. We see stars at all stages of life in the galaxy, and their study allows us to piece together how stars form, and how the rarest ones are different. The image above shows two distinct clouds, both about 5,000 light years away in the constellation Cygnus, along the Galactic plane. The smaller bubble on the left, literally...
Data is beautiful. There is elegance in the artful manipulation of data to communicate information. I love to see new ways to communicate science to the layman and give an understanding of the collective human knowledge. So I had to post this timeline of the universe infographic, containing events from the beginning of the universe all the way up to the death of the Sun. This is obviously just the tip of the scientific iceberg so to speak, but some of the highlights chosen cross several disciplines of science and are truly significant events in history. Enjoy the truly beautiful...
What do other planetary systems look like? We have seen some where massive Jupiter-sized worlds orbit closer to their star than Mercury does to the Sun, baking them with radiation. Others have had multiple rocky planets within the Earth’s orbit distance. Some have planets similar to Earth in a variety of locations. But what about far away from the star? We never expected to find gas giants like Uranus and Neptune in the far reaches of our solar system. Are there planetary systems where planets live even farther away? Maybe there are planets that live in the empty darkness between stars,...
The only reason we can see black holes in the universe is because some of them swallow up gas and dust. This heats up material that is spinning rapidly around the black hole as it falls in (called an accretion disk), and produces massive jets of material due to conservation of angular momentum that can be seen across the universe. The energy released in the jets and the energy given off in the accretion disk are proportional to how much gas and dust is being consumed by the black hole. More matter = more food = more energy released. But...
How do the Mars rovers compare in size and features? Here’s a great photo putting it all into perspective. Included are Sojourner, Spirit/Opportunity, and Curiosity, with a couple of testing officials at NASA’s Jet Propulsion Laboratory. These are not the rovers that were sent to Mars, but are the secondary ones built for testing here on Earth. They cost a lot of money to build too, so NASA keeps them nice and safe.