10) Largest Asteroid
Ceres is the largest asteroid we know of. It is almost 600 miles in diameter which makes it as large as California. It’s massive enough that its gravity forces it to have a spherical shape and also shares the title of ‘Dwarf Planet’. It’s so big, that it contains 25% of the mass of the asteroid belt. If you took all the asteroids in the asteroid belt and glued them together, that new object would only be about 2.5 times as big as Ceres.
9) Largest Planet
Located in the constellation Hercules, planet TRES4 is 70% larger than Jupiter in diameter, but has only 80% of Jupiter’s mass. Because of how close it orbits to its sun, it is thought that the intense heat expands the gasses that make up this planet, resulting in an almost ‘marshmallow-like’ density. It’s holds the title of the largest planet we’ve discovered so far.
Update: Science is never finished. Since this list was compiled, observations of an exoplanet called WASP-17b suggest that it is even bigger than TRES4. Despite its radius being twice that of Jupiter’s, it only has half the mass. This makes it even “fluffier” than TRES4.
8) Largest Star
VY Canis Majoris is the largest star (in diameter) that we know of. It’s in a class of star known as Red Hyper Giants. It’s 2,000 times wider than the sun and would take the world’s fastest race car 2,600 years to circle it once. If you replaced our Sun with VY Canis Majoris, it’s radius would extend out passed Saturn. (see picture to the left for comparison to our own sun).
7) Largest Black Hole
Black holes are not physically large regions of space. But when you include their mass, they are among the top competitors for the largest things in the universe. And quasar OJ287 is the largest black hole we’ve spotted. It’s estimated to be 18 billion times the mass of our sun and is a supermassive black hole located in the center of a galaxy. To put that in perspective, it’s an object larger than our entire solar system. Just how big can a black hole get? According to scientists, there is no theoretical upper limit.
6) Largest Galaxy
A super galaxy is a galaxy that has merged with many others and they sit in the middle of galaxy clusters. The largest that we’ve discovered so far, is arguably the IC1101 super galaxy. It is 6 million light years across. Compare that to the Milky Way which is a mere 100 thousand light years across. IC1101 is a staggering 60 times larger than our own.
5) Radio Lobes
Radio lobes are powered by the accretion disk of super massive black holes. Black holes that sit at the center of most galaxies. As material gets consumed by a black hole, some energy and matter is flung away at high speeds which occur at the poles of black holes. These emissions are in the form of radio energy jets which can be seen with a radio telescope. The largest is located in the galaxy is 3C236 which is located in the constellation Leo minor. Its jets span 40 million light years across. The jets from end to end are by far larger than any galaxy.
4) Lyman Alpha Blobs
These blobs are a very short lived phase of the birth of galaxy clusters. They are an amorphous object filled with gas that are not fully coalesced or bound and set gravitationally yet. They resemble amoebas or jellyfish in shape. The largest one that we know of is 200 million light years wide located in the constellation Aquarius.
3) The Boötes Void
Galaxies usually reside in clusters. Even our own Milky Way does. These clusters are lightly gravitationally bound and expanding along with space/time itself in groups. But what about the areas where they don’t reside? Enter the Boötes Void. This region of ‘nothingness’ is a whopping 250 million light years across. That’s 2,500 milky way galaxies placed side by side. Voids are like holes in our universe, and the Boötes Void is the largest.
2) Shapley Super Cluster
It is the most massive gravitationally bound object that we currently know of. The Shapley Supercluster is a collection of galaxies some 400+ million light years long. This puts our Milky Way galaxy around 4,000 times smaller. It would take our fastest spacecraft trillions of years to cross it.
1) The Cosmic Web
Most astronomers agree that the biggest thing in the universe is the cosmic web. It’s an endless scaffolding of clusters and superclusters of galaxies surrounded by dark matter. It resembles a three dimensional spiderweb, comprised of dark matter and galaxies. Cluststers of galaxies and dark matter make up “hubs” and filaments of galaxies connect these hubs producing a web like appearance. (see side picture)
How big is the web? If the Milky Way galaxy was a poppy seed, then the cosmic web of the observable universe would be the size of the Rose Bowl stadium.
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