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Exoplanets a-bubbling

When you have one-thousand thirty eight confirmed exoplanets. you get to do some pretty cool things with all of that data. The Open Exoplanet Catalogue put together a really cool bubble chart of these planets’ sizes and temperatures.

Screenshot from interactive bubble chart of planets. Credit: Open Exoplanet Catalogue
Screenshot from interactive bubble chart of planets. Credit: Open Exoplanet Catalogue

Pretty, isn’t it? And there’s a whole lot of information packed into each bubble. The size of the bubble corresponds to the relative size of the planet and its color corresponds to its equilibrium temperature. We can think of a planet’s equilibrium temperature as an idealized case where the planet is only heated by its parent star, and there is no warming or cooling due to the planet’s atmosphere. Of course, that’s never the case in real life and that’s why the the folks at the Open Exoplanet Catalogue were careful to point out that “green might be right.”

Take a look at the visualization yourself and spend a few minutes (or hours) hovering over the planets. Visualizations like these are a great way to explore large sets of data like these all at once. And with another 1,073 (and counting) unconfirmed exoplanets, there’s going to be an ever-expanding dataset to explore.

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Proxima Centauri is Far, Far Away

Space is big. Really big. You just won’t believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it’s a long way down the road to the chemist’s, but that’s just peanuts to space.

Douglas Adams, The Hitchhiker’s Guide to the Galaxy

Today an archive Hubble Space Telescope image of Proxima Centauri was released. It’s a beautiful image that shows Proxima as a small red dwarf star about one-tenth the radius of our Sun. As it’s name suggests, Proxima is close by – a scant 4.243 light years away, nary a stone’s throw across the universe.

But “close” is a very relative term here. In fact, the only way we can begin to comprehend the ridiculous distance to the closest star is to scale it down to something we might be able to better comprehend.

Let’s say for the sake of argument I got past security and managed to place a volleyball-sized scale model of our Sun on the top of the Capitol Building in Washington, DC, like so:

The Sun, shrunk down to the size of a regulation Volleyball (radius of about 10.5 cm) placed atop the Capitol Building in Washington, DC. Image from Google Earth
The Sun, shrunk down to the size of a regulation Volleyball (radius of about 10.5 cm) placed atop the Capitol Building in Washington, DC. Click to embiggen. Image from Google Earth

That shrinks our Sun down to a radius of about 10.5 centimeters. Proxima is 4.243 light years away, which on this scale equates to a distance of 6025 km. That means on this scale, Proxima could lie anywhere along this ring around our volleyball sun in DC:

A 6,025km-radius ring drawn around a volleyball-sized Sun atop the Capitol building in Washington, DC
A 6,025km-radius ring drawn around a volleyball-sized Sun atop the Capitol building in Washington, DC. Click to embiggen. Image from Google Earth.

Proxima’s parent star, Alpha Centauri, lies about 155km beyond on this scale, so let’s place both at their respective distances in France:

The Sun in Washington, DC, Proxima Centauri in the French countryside and Alpha Centauri in Paris.
The Sun in Washington, DC, Proxima Centauri in the French countryside and Alpha Centauri in Paris. Click to embiggen. Image from Google Earth

So there you have it. If the Sun were a volleyball atop the Capitol Building in Washington DC, our nearest stellar neighbor would be about 1.5 centimeters in radius – about the size of a large ball bearing – somewhere in the French countryside.

Space is freakishly, mindbogglingly big!

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A Sonata of Supernovae – Music of Stellar Explosions

Supernovae are the most powerful explosions in the universe this side of the Big Bang itself. There are a souple of different ways for stars to go supernova, but Type 1a Supernovae shine with a well-known brightness. Thanks to this characteristic, astronomers can use these explosions to measure the distances to their host galaxies, and figure out cool things such as the expansion of the universe.

They can also be used to create music. Feat your eyes and ears (be sure to go full screen to see the fireworks):

This eerie, hypnotic tune was created by Dr. Alex Parker, an astronomer at the Harvard-Smithsonian Center for Astrophysics. Alex used survey data from the Canada-France-Hawaii Telescope (CFHT) over a three-year period from 2003 – 2006. During this time, 241 Type Ia supernovae were detected in the four star fields surveyed.

Alex assigned each supernova a unique note based on the following criteria:

Volume = Distance: The volume of the note is determined by the distance to the supernova, with more distant supernova being quieter and fainter.

Pitch = “Stretch:” The pitch of the note was determined by the supernova’s “stretch,” a property of how the supernova brightens and fades. Higher stretch values played higher notes. The pitches were drawn from a Phrygian dominant scale.

Instrument = Mass of Host Galaxy: The instrument the note was played on was determined by the properties of the galaxy which hosted each supernova. Supernovae hosted by massive galaxies are played with a stand-up bass, while supernovae hosted by less massive galaxies are played with a grand piano.

The result is a mesmerizing sonata without a rhythm, tempo, or measure, played for us by the titanic destruction of stars in the distant past.