To help you out with your halloween parties, we’ve collected together the spooky sounds of space. Every piece of audio we’re about to play might sound like it comes from a terrifying nightmare dimension, but it’s really just a natural space phenomena.
Astronomy Cast at Dragon*Con 2011: Strange Stuff in Space
This is an impromptu episode of Astronomy Cast that we recorded during Dragon*Con 2011. Pamela was scheduled to speak with a panel about strange things in space, but she ended up being the only person there. So Fraser jumped in, and this was what we did. We mostly talked about unusual things in the Solar System, but a few things in the rest of the Universe.
Ep. 234: Lunar Phases
The Moon is a stark reminder that we actually live in a Universe filled with stars and planets and moons. The changing phases of the Moon show us the relative positions of the Earth, the Sun and the Moon as they interact with one another. Let’s learn about the different phases, the geometry of the whole system, and some of the interesting science wrapped up with our fascination of our only natural satellite.
Ep. 233: Radar
Radar is one of the those technologies that changed everything: it allows boats and aircraft to “see” at night and through thick fog. But it also changed astronomy and ground imaging, tracking asteroids with great accuracy, allowing spacecraft to peer through Venus’ thick clouds and revealing secrets beneath the Earth’s shifting sands.
Ep. 227: The Big Dipper
We wanted to spend a few shows talking about some of the most recognizable constellations in the night sky. We’ve chatted about Orion the Hunter, but now we’re going to talk about the Big Dipper, also known as Ursa Major, or the Great Bear – apologies to our southern hemisphere listeners.
Ep. 226: Weather
How’s the weather? Maybe a better question is… why’s the weather? What is it about planets and their atmospheres that create weather systems. What have planetary scientists learned about our Earth’s weather, and how does this relate to other planets in the Solar System. What is the most extreme weather we know of?
Ep. 225: Ice in Space
A huge part of the Solar System is just made of ice. There are comets, rings, moons and even dwarf planets. Where did all this ice come from, and what impact (pardon the pun) has it had for life on Earth?
Ep. 224: Orion
Most people know how to find two constellations: the Big Dipper, and Orion the Hunter. You can teach a small child to find Orion, and at the right time of year, they’ll find it in seconds. There’s so much going on in this spectacular constellation, from the star formation in the Orion Nebula to mighty red supergiant Betelgeuse, ready to explode. Let’s learn about the history and science of the constellation Orion.
Ep. 223: The Transit of Venus
Since the planet Venus is closer in to the Sun than Earth, there are rare opportunities to see it pass directly in front of our parent star. This is known as a planetary transit, and thanks to the geometry of the Earth and Venus, they only happen a couple of times a century. The transits of Venus have been used by astronomers to unlock the scale of the Solar System, and there’s another one just around the corner.
Ep. 220: Mass Extinction Events
The Earth seems like a safe place, most of the time. But we have evidence of terrible catastrophes in the ancient past. Times when almost all life on Earth was wiped out in a geologic instant. What could have caused so much devastation? And will something like this happen again?
Ep. 217: Stellar Classification
Have you ever heard an astronomer utter these words? Oh be a fine girl and kiss me. They’re not being romantic, they’re trying to remember the different ways to organize stars, as detailed nicely on a Hertzsprung–Russell diagram. Let’s learn what all those letters mean, and what differentiates a type-O star from a type-G.
Ep. 215: Light Echoes
Just as sound can echo off distant objects, light can echo too. And the echoes of light bouncing off stellar remnants, black hole accretion disks, and clouds of gas and dust provide astronomers with another method of probing the distant cosmos.
Ep. 213: Supermassive Black Holes
It’s now believed that there’s a supermassive black hole lurking at the heart of every galaxy in the Universe. These monstrous black holes can contain hundreds of millions of times the mass of our own Sun, with event horizons bigger than the Solar System. They’re the source of the most energetic particles in the Universe, the brightest objects in the Universe, and the place where the laws of physics go to get mangled.
Ep. 203: Europa
Europa is the smallest of the Jovian satellites, but it might be one of the most exciting spots in the Solar System. When NASA’s Voyager spacecraft flew past the moon, they discovered huge cracks in its icy surface. Is it possible that Europa has a huge ocean of liquid water, and maybe even life? This is a world that needs more investigation.
Ep. 202: The Planets at Gliese 581
With the discovery of a planet in the habitability zone of Gliese 581, the chances of finding life on other worlds is just getting better and better. Let’s take a look at the discoveries made at Gliese 581, provide some perspective on the real chances of life, and talk about what might come next.
Ep. 201: Titan
Titan is Saturn’s largest moon, and the second largest moon in the Solar System. It’s unique in the Solar System as the only moon with an atmosphere. In fact, scientists think that Titan’s thick atmosphere – rich in hydrocarbons – is similar to the early Earth, and could give us clues about how life got started on our planet.
Ep. 196: Luminosity and Magnitude
Astronomers measure the brightness of stars as magnitude. But this brightness depends on the distance to the star as well as the total amount of energy it’s pumping out into space. And from our vantage point here on Earth, appearances can be deceiving.
Ep. 195: Planetary Rings
Saturn is best known for its rings. This huge and beautiful ring system is easy to spot in even the smallest backyard telescope, so you can imagine they were a surprise when Galileo first noticed them. But astronomers have gone on to find rings around the other gas giant worlds in the Solar System – the differences are surprising.
Ep. 194: Dwarf Planets
In 2006, the International Astronomical Union demoted Pluto out of the planet club. But they also started up a whole new dwarf planet club, with Pluto, Eris and the asteroid Ceres as charter members. Let’s find out what it takes to be a dwarf planet, and discuss the current membership.
Ep. 182: Astrometry
Astronomers have been cataloging star positions for thousands of years, from the first calculations made by Hipparchus, to the more recent star catalogs made by the spacecraft named after him. This is astrometry; another way to find our place in the Universe.
Ep. 180: Albedo
Why are some objects in the Solar System bright while others are dim? Much of an object’s brightness is caused by its albedo, or how well it reflects radiation from the Sun. If you want to know how big a distant moon, comet, or asteroid is, you’ve got to know its albedo.
Ep. 177: Mysteries of the Milky Way, Part 2
We survived our first group of mysteries, so now we move onto our second set of stuff of amazing Milky Way mysteries. How many spiral arms does our galaxy have, and why does everything keep dying every 60 million years or so?
Ep. 176: Mysteries of the Milky Way, Part 1
We’ve wrapped up our Solar System mysteries and now we move onto the Milky Way mysteries, and the some of the general mysteries of galaxies. From blue stragglers to Eta Carinae… what’s going on?
Ep. 175: Mysteries of the Solar System, Part 2
Apparently this is at least a 2 part series. This week we continue examining some of the baffling mysteries of the Solar System, where we fill your head with more questions than answers. Sometimes we’ve just got to share the enjoyment of not knowing the answer.
Ep. 174: Mysteries of the Solar System, Part 1
We know a lot about our Solar System, but there’s an awful lot that’s a complete and total mystery. Today we’re going to begin a series of unknown length examining some of these mysteries, and explain the best theories astronomers have so far.