It’s easy to get lost in fantasy worlds through science-fiction movies and novels, but did you know that some of your favorite fairy-tale characters actually exist in cosmic form? From dwarfs and giants to shape-shifters and buried treasure, the universe is home to a multitude of mystical objects.
White Dwarf Stars
This Hubble Space Telescope image of M4, the nearest globular cluster, reveals white dwarf stars that are 12-13 billion years old.
NASA and H. Richer (University of British Columbia)
You’ve probably heard of dwarfs like Happy and Sneezy (or Gimli and Thorin), but it’s unlikely you’re familiar with the space-dwelling dwarfs with names like Sirius B and ASASSN-16oh. White dwarf stars like these are typically about the size of Earth, which is pretty small as far as stars go. They represent one of three final stages of stellar evolution, along with neutron stars and black holes. Each star’s original mass determines which one it will ultimately become. Stars much more massive than the Sun typically become neutron stars or black holes, and lower-mass stars end up as white dwarfs.
In this artist’s concept, an asteroid (bottom left) breaks apart under the powerful gravity of LSPM J0207+3331, the oldest, coldest white dwarf known to be surrounded by a ring of dusty debris. Scientists think the system’s infrared signal is best explained by two distinct rings composed of dust supplied by crumbling asteroids.
NASA’s Goddard Space Flight Center/Scott Wiessinger
Our Sun will eventually become a white dwarf after it exhausts its fuel, but don’t worry – we’ve got several billion years to go! Before it is reduced to a white dwarf, it will expand into a red giant, swelling out to encompass Earth’s orbit. But we don’t have to wait billions of years to see stellar giants … some already peek out at us from the cosmic deep.
Giants and Supergiants
The Cassini spacecraft took a series of images on Sept. 9, 2006, as it watched the bright red giant star Aldebaran slip behind Saturn's rings. This view shows the Encke Gap (325 kilometers, or 200 miles wide) and the faint ringlets which share the gap with the embedded moon Pan. Bright Aldebaran is overexposed, creating thin vertical lines on its image.
NASA/JPL/Space Science Institute
The red giant star Aldebaran, located about 65 light-years away, is about 5,000 times bigger than Earth. Our Cassini spacecraft imaged Aldebaran through Saturn’s rings in 2006, but you can see it for yourself during northern winter. Just look for the brightest star in the constellation Taurus.
This artist’s concept shows a supergiant to scale with the Sun. A supergiant is a star with about 20 times the Sun's mass that still retains its deep hydrogen atmosphere, making it hundreds of times the Sun's diameter.
NASA's Goddard Space Flight Center/S. Wiessinger
Fairy tale giants may be taller than trees, but these supergiant stars can be over 100,000 times “taller” than our entire planet! Supergiant stars are likely becoming more rare as time goes on. While scientists believe they used to be more common, our whole galaxy now contains just a small smattering of supergiants.
When a star that is eight times larger than the sun ends its life, it does not go gentle into that good night. Shifting pressure in its core causes it to collapse and trigger a supernova, as shown here. The initial flash of light, which can outshine the star’s host galaxy, may last only seconds. But the resulting debris that is flung into space can be studied for millennia.
Courtesy of ESA/Hubble/L. Calçada
These massive stars grace the galaxy for a relatively small amount of time. They burn through their fuel extremely quickly – in just a few million years, as opposed to hundreds of billions of years for the smallest stars! Supergiants often end their lives in dramatic explosions called supernovae.
This is the first direct image of a star other than the Sun, made with NASA's Hubble Space Telescope. Called Alpha Orionis, or Betelgeuse, it is a red supergiant star marking the shoulder of the winter constellation Orion.
Andrea Dupree (Harvard-Smithsonian CfA), Ronald Gilliland (STScI), NASA and ESA
Betelgeuse – the bright, reddish star marking the shoulder of Orion – is nearing the end of its life and has expanded to become a red supergiant star. It is destined to explode as a supernova, which might happen tonight … or within the next few hundred thousand years.
Ghostly Solar Neutrinos
Elusive particles called neutrinos fly through space in this animation.
NASA's Goddard Space Flight Center Conceptual Image Lab
Even an average star like our Sun has some seemingly magical qualities. Each second, it sends billions of phantom-like neutrino particles out into space. They travel almost as fast as light and don’t usually interact with normal matter. Billions of them are zipping harmlessly straight through your body while you read this. Even at night they go through the entire Earth before reaching you!
Animation of a neutrino oscillation, where a neutrino changes characteristics over time.
NASA's Goddard Space Flight Center
But that’s not all … these ghostly particles are shape-shifters, too! Neutrinos can change characteristics over time, morphing between different versions of themselves. Scary!
Buried Treasure in the Heart of the Galaxy
The center of our Milky Way galaxy is hidden from the prying eyes of optical telescopes by clouds of obscuring dust and gas. But in this stunning vista, NASA’s Spitzer Space Telescope's infrared cameras penetrate much of the dust, revealing the stars of the crowded galactic center region.
NASA, JPL-Caltech, Susan Stolovy (SSC/Caltech) et al.
Extensive clouds of dust enshroud the heart of our Milky Way galaxy, hiding it from our view — at least when it comes to visible light. The dust isn’t as big a problem for infrared light, however, which has allowed us to get a glimpse of our galaxy’s chaotic core thanks to our Hubble and Spitzer space telescopes.
Future missions may peer into the galactic core in search of buried treasure — thousands of planets orbiting distant stars! It will be exciting to see what hidden gems we uncover next.
