The Bubble Nebula Is a Giant Soap Bubble In The Sky
1 of 5
Even though the Bubble Nebula was first discovered in 1787, our most complete view of it didn't come until April 2016, when a mosaic of four images was released from the Hubble Space Telescope's Wide Field Camera 3. This mosaic showed the nebula in its entirety, including the almost perfectly round shell that gives it its name. That shell is caused by a star 20 times the mass of our sun emitting a powerful flow of gas, or solar wind, that pushes its surrounding material outward into a bubble-like shape. Confined by a molecular cloud that's constantly resisting this outward push, the sphere is nonetheless growing, its ten-light-year diameter expanding outward at more than 100,000 kph (62,000 mph). The strangest thing about the nebula, however, is where this star is located. For a shape this round, you might expect the star to sit in the center, but it doesn't. It sits off to one side. Astronomers aren't quite sure why this is the case, adding extra mystery to an already fascinating astronomical body. We've collected some awesome videos on this topic. Watch them now to learn more.
The Boomerang Nebula Is The Coldest Place In The Known Universe
2 of 5
You might imagine that the coldest place in the universe would be deep in the recesses of space, far away from the warming rays of a star. On the contrary, it turns out that the coldest place in the universe is directly surrounding a star, albeit a dying one. The Boomerang Nebula is a cloud of gas that's being shed by a small dying star on its way to becoming a red giant. The nebula is expanding at an incredible rate, expelling gas at about 102 miles (164 km) per second. That's why it's so cold: as gas expands, its temperature drops. So why is the nebula shaped like a boomerang? It's not, actually. The first astronomers to spot it with a ground-based telescope in 1980 noticed it had a lopsided shape, and perhaps because they were Australian, a boomerang was the first thing that came to mind. Later, in the late 1990s, researchers took a higher-resolution glance with the Hubble Space Telescope and saw that it actually had a double-lobe structure, kind of like a bow-tie. Finally, in 2013, astronomers took an even closer look and found that it's just a round cloud of gas. A ring of dust had been blocking some of its light, making it look like a bow-tie.
from SciShow Space
Key Facts to Know
The Boomerang Nebula is a pre-planetary nebula: or a low-mass star that's near the end of its life. 0:52
The Boomerang Nebula is -458ºF (272ºC), or 1 Kelvin -- just above absolute zero. 1:45
The nebula isn't shaped like a boomerang. Astronomers once thought it was shaped like a bow-tie, but it turned out to be round -- a ring of dust was blocking some of the light. 2:42
The Crab Nebula Is The Supernova That Shone During The Day
3 of 5
When a star explodes in a giant supernova, it leaves quite an impression on the universe. There are plenty of supernova remnants, known as nebulae, visible by telescope, though because of their distance we're seeing them as they were hundreds of millions or even billions of years ago. Rarely do we get to see one in the act of exploding by telescope; much less with the naked eye. But that's exactly what happened when the Crab Nebula formed nearly a millennium ago. Related: The Bubble Nebula Is a Giant Soap Bubble In The Sky
from SciShow Space
Key Facts to Know
When the supernova that became the Crab Nebula appeared in 1054, it was 4 times brighter than Venus. 0:04
The Crab Nebula measures around 10 lightyears in diameter, which is far bigger than our solar system. 2:01
The combined mass of the Crab Nebula and its pulsar is much less than what it should be, puzzling scientists. 2:58
The Pillars of Creation Have Been Destroyed
4 of 5
Pillars of Creation is a photograph taken by the Hubble Space Telescope of interstellar gas and dust in the Eagle Nebula. Located around 7,000 light years away and measuring 4 light years tall, these trunks may have been destroyed years and years ago.