This artist’s impression pinpoints many cosmic voids –– relatively empty bubbles of space.
The universe is home to trillions of galaxies, each chock full of smaller cosmic objects like stars and planets. Since galaxies gravitate together in a web-like pattern, there are also immense open spaces called cosmic voids in between. In those growing, gloomy places, dark energy dominates.
Galaxies in this animation are structured a bit like a Hoberman sphere (a lattice-like toy ball that expands and collapses), growing farther apart as the universe expands.
Zoomed out maps of the universe show that galaxies often cluster together in bright city-like regions. Each cosmic metropolis is connected to others by interstate highways – vast filaments of dark matter, gas, and dust, along which additional galaxies can be found. This large-scale structure is called the cosmic web.
Way out in the boondocks – far from the galaxies and filaments – are the cosmic voids. They’ve been growing larger for billions of years, emptying out as gravity pulls matter elsewhere.
This animation visualizes the early universe, when the cosmic was full of a hot plasma soup.
Cosmic voids were born when the universe looked extremely different than it does today. Instead of being speckled with stars and galaxies, the cosmos was filled with a sea of plasma (charged particles) that formed a dense, almost uniform fluid.
There were slightly denser kernels of matter, like a single ounce of cinnamon sprinkled into about 13,000 cups of cookie dough! Since the clumps had more mass, their gravity attracted additional material. Those areas grew and grew, drawing more matter together to form stars, galaxies, and galaxy clusters as the universe expanded over billions of years. Meanwhile, the spaces in between became ever emptier.
A simulation of large-scale structure forming under the influence of gravity.
Cosmic voids aren’t completely empty, though. They do have sparse galaxies, though they seem to have delayed development. Since there’s less matter, there’s weaker gravity pulling things together so stars and galaxies form more slowly. And those galaxies are isolated so they’re less likely to interact with others, which fuels growth in denser places like galaxy clusters.
But voids are mostly filled with things we can’t see. They contain a thin mist of dark matter along with a relatively larger amount of WIMPS (weakly interacting massive particles) like ghostly neutrinos than we find elsewhere in the universe. Since there’s not very much stuff in voids to create gravity, a different force reigns supreme: dark energy, the mysterious cosmic pressure that seems to be speeding up the universe’s expansion. Since cosmic voids are influenced primarily by dark energy, they offer clues about its behavior.
Astronomers haven’t thoroughly studied cosmic voids yet, but our upcoming Nancy Grace Roman Space Telescope will be wide-eyed enough to reveal those desert patches of space like we’ve never seen them before. Studying them will show how the universe is put together and how dark energy is pushing galaxies apart.
If you could fly through the cosmic web at hyperspeed, you might see a view like this simulated one!
So far, scientists have found around 1,000 cosmic voids. Roman’s 3D surveys should find tens of thousands more, both large and small, scattered throughout earlier cosmic eras than previous large sky surveys could see. That means we’ll be able to watch how the most vacant places get even emptier over billions of years. And astronomers can trace any changes in dark energy’s might by seeing how it stretches voids, where dark energy dominates, across cosmic time.
Follow along with Roman’s journey to launch at nasa.gov/roman.
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Who is the older brother or sister? Legend or Fable And who is the younger brother or sister? Legend or Fable
Legend and Fable are twins! (And to actually answer your question: technically, Fable’s older :) )
And while I’m at it, I might as well clear up the relative ages of some other Wisdomverse siblings.
Siblings of the Zelda series!
Prince Hansen is canonically older than Echo!
I’m following the AoL manual’s text, which explicitly states that he’s Zelda’s older brother. He just… looks young in this depiction, loll. I draw him a bit older than this for WV!
(Note that, after EoW, he’s mentally about the same age as Echo, since he spent two years in stasis after falling into the Still World in Echo of the Past. This may explain his youth :) .)
I don’t mind either way, but I like to write Linkle as older than Wars!
They’re not canonically related at all, but the idea that they would be siblings was apparently briefly considered during development. I like it, and nothing in the game disproves it, so I consider it canon to WV.
I like to think Linkle, as the older sibling, was always convinced she would be the hero— and that’s why she stayed back in the village, while Wars went off to enlist in the army as a common soldier. Wars was shocked when Artemis identified him as the hero. He kinda thought that whole hero business was just a delusion. Linkle was shocked when she found out, and eventually reconciled herself with the fact that she’s still a hero, if not the hero.
They’re only about a year apart in age, imo.
The Colors don’t really have canon ages— but I like to think their ages go in reverse of the order the Elements are infused into the Four Sword in Minish Cap, with Green at the head. Like the personalities were split in LIFO order.
So Green’s the oldest, followed by Blue, then Red, then Vio.
Vio is a little miffed that he’s the youngest, but he doesn’t really mind that much. And that doesn’t stop all of them from being protective of Red, including Vio.
Wind and his little sister Aryll form the second actually canon sibling pair in this list (Echo and Hansen are the first), but…
The original BotW concept art also gave Wild an unnamed little sister! I’m definitely not the one who first discovered this or decided to use it, but I’ve kept it canon to WV in this one small line here:
I like to think her name was also Aryll (since she’s the younger sister of a Link). Whoever she was, it’s likely that Wild doesn’t remember much of her— and she likely died in the Calamity 100 years ago 🥲
This image, released in celebration of Earth Day, shows the terminator – the line between night and day – on Earth. The Artemis II astronauts captured this view on April 2, 2026, during their journey to the Moon.
NASA science improves life on Earth every day. We provide insights on our home planet that can only be gathered from space, which can then be used for disaster response, farming, and more. In addition, our observations of Earth and the technologies we develop provide the foundation needed to explore and sustain human life on the Moon, Mars, and beyond.
Download this year's Earth Day poster.
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