Alliteration is accessible to all! Okay I’m done. Start some science! Really done this time. Today’s double post covers the smallest of stars, still larger than most planets, and the only weather Mercury will ever have. Humans are naturally interested in the extremes, the biggest, smallest, fastest, hottest, coldest, and every other characteristic outlier. With stars, being so huge and powerful, we are often more interested in the largest, hottest, and most energetic. Though on the opposite end of the spectrum, Cambridge University astronomers have discovered the smallest star in the known universe. The star, a red dwarf, has the...
Last week, while looking at some of the best images from the Cassini spacecraft, I commented on the fact that the smooth rings of Saturn are small, varied chunks of ice and rock when you get down to the smaller scales. Reflecting on that this morning, I was thinking about how observing objects in our universe at smaller scales gives new insight into the variety and complexity of natural phenomena. Not long after, I came across a story of a new interesting object in our own Solar System. A new binary asteroid was discovered. This in itself isn’t too different...
A pretty cool result came out of Cornell University this week, showing that Mars was struck by a pair of ancient asteroids that caused massive tsunamis. Not only is it the first evidence of a tsunami event on another world, but it proves that Mars once had a large ocean. The study looked at ancient shorelines between the lowlands and highlands of Mars, where the ocean-land boundary would have been. Two massive impacts, a few million years apart, extended the shorelines and caused turmoil with the Martian climate at the time. “About 3.4 billion years ago, a big meteorite impact triggered...
Have you ever seen a picture of a comet or asteroid in the sky against a background of stars? Here let me show you. Can you spot the asteroid? Okay I confess there is no asteroid in the image above, but if there was you’d believe me because an asteroid in this image would be indistinguishable from the stars. They are all points of light, so how can you tell them apart? There’s something that separates asteroids, comets, planets, and all other solar system objects from background stars in an image. When you’re driving in a car and you look to the...
What is the difference between a comet and an asteroid? The typical response is that an asteroid is rocky and a comet is icy/gassy. Further than this, asteroids typically orbit closer to the Sun than Neptune, and comets orbit beyond this loose dividing line. But as with everything in nature, there are often exceptions to the rule. C/2014 S3 PANSTAARS is classified as a weakly active comet, originating in the Oort cloud with an orbital period of 860 years. As it approached the Sun, astronomers noticed that it was lacking the characteristic comet tail, resulting from the blast of solar radiation upon approach to the...
I saw this pop up on Reddit yesterday, where user /u/bubbleweed posted a video to r/astronomy showing Jupiter with a clear sign of an impactor. It was independently observed in Austria at the exact same time. Notice that both videos show the exact same thing. In the reddit thread, users encourage the original poster to report it to the Planetary Virtual Observatory and Laboratory in hopes of getting follow up from the Hubble telescope. It is strikingly similar to a 2010 confirmed impact event. The ‘explosion’ of the potential impactor might make you think it’s fake, that it couldn’t explode because...
When we see the Earth’s only Moon up in the sky, we often think about how small it is. It’s only about 1/4 the diameter of the Earth, and at a distance of 384,000 Km, it looks small in the sky. But often size is entirely a matter of perspective. What we compare something to, that’s what determines it’s size. When the Moon is high in the sky we easily compare it to the size of the window we are looking through, or to a nearby tree, or our outstretched hand. All of this can make the Moon seem pretty tiny....
Since the arrival of the Dawn spacecraft in March of 2015, we have seen tremendous views of the dwarf planet Ceres. Lying within the asteroid belt, it is revealed to be a frozen world of ice and rock, with many interesting features. None of these features had generated more intrigue than the famous bright spot in the bottom of what is now called the Occator crater. The icy spot has had astronomers guessing for months whether it is a cryovolcano, water ice, frozen carbon dioxide, or something even more strange and rare. As the Dawn spacecraft has moved into a...
Everyone in Canada looks forward to the Perseid meteor shower each August. The weather is warm, the skies are clear, and they have a high zenithal hourly rate (ZHR). But once they are done, it’s not long before the weather starts to cool down, Canada moves into Autumn and eventually the deep freeze of winter sends our fine nation into hibernation. But if you do feel like coming out of your fort this weekend, in an unseasonably warm December, you will be treated to what has often been the best meteor shower of the year: The Geminids. Under ideal conditions,...
With the recent story of the star with a debris ring potentially being a sign of extraterrestrial life (spoiler alert, it’s not aliens), I had to talk a bit more about debris rings in general around other stars. How can they exist? When we start to look at the number of worlds and the variability of objects and stars, it would be no surprise to find strange systems where recent interactions have produced all kinds of fascinating patterns. It’s another example of finding art in nature. A group of astronomers from the university of Warwick have directly imaged a debris...
