Starts With A Bang!

The Universe is out there, waiting for you to discover it.

Sharing Your Art

"And from it all, here are the lessons I learned: to try not to be so rigid. Yes, some things (like my new sketchbook) are sacred, but if you let go of those chains, new and wonderful things can happen. Those things you hold so dear cannot change and grow and expand unless you loosen your grip on them a little. In sharing my artwork and allowing our daughter to be an equal in our collaborations, I helped solidify her confidence, which is way more precious than any doodle I could have done. In her mind, her contributions were as valid as mine (and in truth, they really were). Most importantly, I learned that if you have a preconceived notion of how something should be, YOU WILL ALWAYS BE DISAPPOINTED. Instead, just go with it, just ACCEPT it, because usually something even more wonderful will come out of it."

When you let a four-year-old into your sketchbook, you’d never expect them to make it better, would you? That’s exactly what happened to Mica Hendricks; come see her amazing collaborative artwork with her daughter, Myla!

Ask Ethan #52: How long has the Universe been accelerating?

"What it tells us is that space between galaxies — or between any structures that aren’t gravitationally bound to either one another or mutually bound to an even larger structure — is going to expand. If we want to learn how that space is going to expand, meaning at what rate, we need to know two pieces of information:

1. What the expansion rate is at any point in our cosmic history, and

2. What types and ratios of matter-and-energy are present in our Universe.

That’s it! If we can figure out those two pieces of information, we can figure out not only the fate of our Universe, but what the expansion rate was, is and will be at all times since the Big Bang.”

The Universe has always had dark energy in it, but it’s only started accelerating recently. Thanks to the precision measurements of Planck, we can finally know exactly when the transition from a decelerating Universe to an accelerating one happened. Come find out on this week’s Ask Ethan!

Back-to-school advice for STEM students

"You might hear your peers or friends grumble something like, “when am I ever going to use this?” Depending on what you grow up to do, the answer may, in fact, be never. You may never use the things you’re working hard to learn. But there is a very good reason to learn them anyway, and it’s a very simple reason: you need to challenge yourself. You need to learn new things, and you need to force your brain to learn how to solve problems it’s never had to solve before. Imagine two versions of yourself, and the brains inside these two versions: one that only learned things you needed in your adult life, and one that learned as much as you could about as many different things as you could. Which version, do you think, would have the stronger brain? Would have the better problem-solving skills? Would be better able to tackle the unknown challenges that lie ahead?

I’ll say it once more: learn as much as you can about as many different things as you can. Challenge yourself!”

The best back-to-school advice you can give to an aspiring young student with a talent for math, science, technology or engineering!

Could Dark Matter just be Normal Stuff that’s Dark?

"[I]f we take two galaxy clusters and collide them, and we see the effects of gravitation (from gravitational lensing, in blue) and the aftermath of high-speed gaseous collisions (emitting X-rays, in pink), doesn’t their failure to match up indicate dark matter? Not necessarily; it only tells us that there isn’t enough gaseous dark matter to explain all of the gravitational effects. But you can also see that the optical matter — the collections of stars in galaxies — passed right through one another, the same way that two guns filled with birdshot and fired at one another would have all but very few pellets miss one another."

Even something as convincing as the famed bullet cluster doesn’t prove the existence of non-baryonic dark matter; it takes a whole lot more. Yet, we know it’s real! Come find out how.

The Stars Beyond

"Each galaxy has a story. Some are small but growing rapidly. Others look bland but betray a complex, vibrant past. What’s more, most large galaxies — again like some cities — appear to be built upon the ruins of smaller, more ancient ones. Our home galaxy, the Milky Way, is not unlike Rome in this respect. Ancient stellar remains show up viscerally in the the faint, extended outer reaches of galaxies — regions of light so diffuse that they’ve been difficult to study until recently."

You’ve no doubt heard of dark matter halos around galaxies: vast, extended, spherical collection of mass that reach for hundreds of thousands of light-years beyond what we typically think of as a spiral or elliptical galaxy. But did you know that galaxies contain vast, extended stellar halos as well? Moreover, they look nothing like you’d expect! They’re not spherical or even ellipsoidal, but highly irregular, and have an awful lot to teach us about how galaxies came to be the way they are today. Galaxy evolution expert James Bullock has the story.

The Brilliance of Scientific Assumption

"An alternative solution is that Newton’s inverse-square assumption was wrong. Astronomer Simon Newcomb, for example, demonstrated that Mercury’s anomalous precession could be accounted for by “correcting” Newton’s equation to be to the power of 2.0000001574. Most astronomers at the time thought such an idea was unlikely, and later observations of lunar motion showed that Newcomb’s correction didn’t work for the Moon. So a planet Vulcan seemed to be the likely solution.

But it turns out that Newcomb was closer to the truth. When Einstein developed the theory of general relativity, one of the predictions was that Newton’s inverse-square relation wasn’t exact. From this, Einstein was able to show that the Mercury anomaly was due to relativistic corrections.”

When you make an assumption, you make an ass out of you and “umption”. Also, that’s how the greatest leaps forward in all of science are made! Brian Koberlein has the scoop.

Messier Monday: The Flattened Fake-out Globular, M19

"In reality, what we’re looking at is a huge globular cluster, some 70 light-years in radius and containing about 1,100,000 times the mass of our Sun inside of it: one of the largest globular clusters in our galaxy! At 29,000 light-years distant, it’s slightly on the other side of the galactic center from us, and its stars are typically about 11.9 billion years old, or nearly three times the age of the Sun."

Globular clusters are almost always perfectly spherical, but this object is very clearly flattened. But is it *really* oblate like it appears, or is the Universe lying to us? Spoiler for this Messier Monday: it lies!

Weekend Diversion: The Universe in your home

"One of the greatest things about all NASA images is that they’re entirely public domain, which means that you are free to use them for whatever non-commercial purposes you like. Want a poster? Just have it printed out!

But what if you want to decorate your room, office, house or apartment with curtains or wallpaper of these fantastic images? This weekend, I’m super excited to introduce you to Spoonflower, a site that specializes in custom fabric, wallpaper and gift wrap.”

Ever want to take the greatest NASA photos in history and turn them into fabric, curtains or wallpaper? Now you can! Come learn how, and discover the power you gain from combining NASA’s greatest images with Spoonflower!

Ask Ethan #51: Is Astrology A Science?

"Before we knew about axial tilt, heliocentrism or the nature of stars themselves, much less the basics of a more complex science like biology, how were we to know what caused something like the seasons on Earth? And moreover, when you begin to observe that people behave differently year-to-year or season-to-season, or that people born at one specific time seem to have different traits, what do you attribute it to?"

It’s a reasonable-sounding idea, but does it stand up to scientific scrutiny?