Category: astronomy

This Is How Amateur Astronomers Can Image What…

This Is How Amateur Astronomers Can Image What Professionals Cannot

“The Universe is full of astronomical wonders, but it’s up to humanity to observe and analyze them. The key factors determining what we can reveal are resolution, light-gathering power, and the wavelengths filters we choose. Professionals have larger, more powerful telescopes with superior instruments, but amateurs have the advantage of time.”

Have you ever looked at a spectacular image of a distant object in the sky and thought there was no way you could ever construct something like that? That it would simply be impossible to take such a large, high-quality image without the benefit of a professional telescope, observatory, or setup? Well, Ciel Austral, a team of five amateur astronomers, spent 10 months over 2018 and 2019 photographing the nearest large galaxy to our own: the Large Magellanic Cloud. They recorded a total of 1060 hours of observations over that time, stitching a total of 620 GB of data together into a single mosaic.

The results are in, and it’s a spectacular view of the LMC that severely outstrips anything professionals have done. Come get the story and some amazing views here today!

This Is Why Earth’s Oceans And Skies Are…

This Is Why Earth’s Oceans And Skies Are Blue

“The sky and ocean aren’t blue because of reflections at all; they’re both blue, but each of their own volition. If you took our oceans away entirely, a human on the surface would still see blue skies, and if you managed to take our skies away (but still somehow gave us liquid water on the surface), our planet would still appear blue.

For the skies, the blue sunlight scatters more easily, and comes to us indirectly from where sunlight strikes the atmosphere as a result. For the oceans, longer-wavelength visible light gets absorbed more easily, so the deeper they go, the darker bluer the remaining light appears. Blue atmospheres may be common for planets, as Uranus and Neptune both possess them, too, but we’re the only one we know of with a blue surface. Perhaps when we find another world with liquid water on its surface, we won’t be so alone in more ways than one!”

The sky is blue. The oceans are blue. Earth, as seen from space, is blue. But have you ever stopped to think about why? Many popular but incorrect explanations abound, such as the idea that sunlight is blue, that oxygen is blue, or that one reflects the other. Of course, none of these are correct! The sky really is blue, and it’s blue because of the physics that governs how light passes through the atmosphere. The ocean is really blue, too; it’s why our planet appears blue from space. But the physics of why the ocean is blue is completely independent of why the skies are blue!

Want to get the real reason why Earth’s oceans and also our skies are blue? Come get the science you crave today.

Scientists Solve The Mystery Of STEVE, And Fin…

Scientists Solve The Mystery Of STEVE, And Find It’s So Much More Than An Aurora

“Normally, aurorae are produced by the Sun’s charged particles striking the atoms in Earth’s upper atmosphere. The solar wind particles get bent by Earth’s magnetic field, exciting and ionizing oxygen, nitrogen, and hydrogen. When electrons recombine with ions, they cascade back down to lower energies, creating aurorae from their emission lines. STEVE is distinct from this for multiple reasons.”

It isn’t often that a naked-eye skywatcher gets a chance to observe an entirely new optical phenomenon that’s never been seen or recorded before. Yet earlier this century, that’s exactly what’s happened with a purple/green/mauve ribbon of light that sometimes appears in the sky. Known as STEVE, for strong thermal emission velocity enhancement, this ribbon includes colors never seen in an aurora, appears at lower latitudes than those where aurorae are typically found, and most importantly, isn’t created coincident with the precipitation of charged particles. In other words, it’s an entirely new phenomenon!

The mystery of what creates STEVE has now been solved, and it’s not only a great scientific story, it’s also beautiful to behold. Come see the full story (and some great photos and videos) today!

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When Did The Universe Become Transparent To Li…

When Did The Universe Become Transparent To Light?

“The Universe became transparent to the light left over from the Big Bang when it was roughly 380,000 years old, and remained transparent to long-wavelength light thereafter. But it was only when the Universe reached about half a billion years of age that it became fully transparent to starlight, with some locations experiencing transparency earlier and others experiencing it later.

To probe beyond these limits requires a telescope that goes to longer and longer wavelengths. With any luck, the James Webb Space Telescope will finally open our eyes to the Universe as it was during this in-between era, where it’s transparent to the Big Bang’s glow but not to starlight. When it opens its eyes on the Universe, we may finally learn just how the Universe grew up during these poorly-understood dark ages.”

There are two ways that astrophysicists talk about the Universe becoming transparent. The first is when the particles from the Big Bang finally form neutral atoms, becoming “transparent” to the leftover photons from that era. The second is hundreds of millions of years later, when those same neutral atoms are reionized, and starlight can travel freely through intergalactic space. Which one is right? When did the Universe become transparent to light? 

The truth is we need them both, as they make the Universe transparent to different types of light. Come get the full story today.

Ask Ethan: How Does The Event Horizon Telescop…

Ask Ethan: How Does The Event Horizon Telescope Act Like One Giant Mirror?

“I’m having difficulty understanding why the EHT array is considered as ONE telescope (which has the diameter of the earth).
When you consider the EHT as ONE radio telescope, I do understand that the angular resolution is very high due to the wavelength of the incoming signal and earth’s diameter. I also understand that time syncing is critical.
But it would help very much to explain why the diameter of the EHT is considered as ONE telescope, considering there are about 10 individual telescopes in the array.”

Humanity has imaged a black hole’s event horizon! It’s been less than a month since the news was announced, and it’s still hard to get over what a phenomenal achievement it was. It’s very difficult to conceive of how, though, we can treat 8 different telescopes and telescope arrays, all stitched together, as acting like a single giant mirror. But that’s exactly what the Event Horizon Telescope did. In fact, that’s what it needed to do, or it would never have been able to achieve the resolutions necessary to construct the first image of a black hole’s event horizon.

But we have it! We achieved it! And here’s the conceptual way you can understand it, even if you barely understand the way a single telescope works.

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This Is What Our Sun’s Death Will Look L…

This Is What Our Sun’s Death Will Look Like, With Pictures From NASA’s Hubble

“Single stars often shed their outer layers spherically, like 20% of planetary nebulae. Stars with binary companions frequently produce spirals or other asymmetrical configurations. But the most common shape for planetary nebulae is a bipolar morphology, containing two opposing jets. The leading explanation is that many stars rotate rapidly, which generates large-scale magnetic fields. Those fields accelerate the loosely-held particles populating the outer stellar regions along the dying star’s poles.”

Our Sun is in for a long life, having over 5 billion additional years until it becomes a red giant, and then will burn helium in its core until it’s approximately 7 billion years from now. But when its core exhausts its fuel, the tenuously-held outer layers will get expelled, while the core contracts down to a white dwarf. The intense heat and radiation from this phase will ionize the outer regions and illuminate the skies in a spectacular show known as a planetary nebula. Although this phase might last a mere 10,000 years, the death throes of Sun-like stars can be seen all throughout the galaxy, and is one of the most spectacular sights there is.

What will our Sun look like, and what do the Sun-like stars we see today, going through this phase, show and teach us? Take a look inside and find out!

This Is How To Bring Dark Skies Back In An Inc…

This Is How To Bring Dark Skies Back In An Increasingly Developed World

“A dark night sky is something we not only all deserve, it’s something that we could very easily have for a relatively small investment. The benefits, in addition to long-term cost savings, education, and the environmental positives, can be taken in all at once by everyone who both lives in, or simply passes through, your town.

And for those of you still asking, “what benefit is that?”

As soon as you encounter your first dark sky community, you’ll see for yourself that there’s no explanation required. To take it all in, just look up.”

When was the last time you saw the Milky Way? If you’re like 99% of the United States or Europe, it wasn’t from your own backyard. While you might assume that’s because we need to have well-lit areas where most of us live, that’s only partially correct. It’s because we choose to have brightly-lit areas to meet our safety and commercial nighttime needs, but there’s a fundamental difference between well-lit and brightly-lit. More than 20 independent communities have taken all the steps necessary to restore darkness to their areas, following the recommendations and getting certified by the IDA: the International Dark Sky Association.

Forget about asking, “why aren’t there more?” Instead, try being the change you want to see, and work to bring dark skies, as well as health and environmental benefits, back to your own community!

This Is How To Bring Dark Skies Back In An Inc…

This Is How To Bring Dark Skies Back In An Increasingly Developed World

“A dark night sky is something we not only all deserve, it’s something that we could very easily have for a relatively small investment. The benefits, in addition to long-term cost savings, education, and the environmental positives, can be taken in all at once by everyone who both lives in, or simply passes through, your town.

And for those of you still asking, “what benefit is that?”

As soon as you encounter your first dark sky community, you’ll see for yourself that there’s no explanation required. To take it all in, just look up.”

When was the last time you saw the Milky Way? If you’re like 99% of the United States or Europe, it wasn’t from your own backyard. While you might assume that’s because we need to have well-lit areas where most of us live, that’s only partially correct. It’s because we choose to have brightly-lit areas to meet our safety and commercial nighttime needs, but there’s a fundamental difference between well-lit and brightly-lit. More than 20 independent communities have taken all the steps necessary to restore darkness to their areas, following the recommendations and getting certified by the IDA: the International Dark Sky Association.

Forget about asking, “why aren’t there more?” Instead, try being the change you want to see, and work to bring dark skies, as well as health and environmental benefits, back to your own community!