Tag Archives: supernova

Watch A Four-Year Timelapse of A Mysterious Cosmic Explosion Captured By the Hubble Telescope (Video)

Back in January of 2002, astronomers witnessed a huge explosion from the star V838 Monocerotis, a red variable star about 20,000 light years away from our Sun.

At first, they thought it was a typical supernova (the explosion of a dying star), but after watching the explosion dim then brighten twice over a period of only a few months (supernovas will usually only dim after the initial bright explosion), astronomers really weren’t sure what they were dealing with.

Check out a time-lapse of the explosion from 2002-2006 below (full screen highly suggested).

So what exactly is going on with this explosion? Well, there are five possibilities that have been proposed so far:

  1. The explosion was a supernova, just a very unique one with a multi-outburst pattern, which would explain the multiple brightening and dimming events. Most scientists agree that the large size and young age of the stars in that region makes this explanation unlikely, however.
  2. The explosion was a thermal pulse. When moderately-sized stars run out of fuel, they explode (in a supernova), leaving behind a dense core of hydrogen and helium. Sometimes this hydrogen and helium core can be re-ignited, illuminating the layers of ejected star material from the supernova explosion. Again, however, the star’s young age makes this possibility unlikely.
  3. Another theory also proposes a helium flash, but one that occurred as a result of thermonuclear processes in a massive supergiant star. Supergiants can be large enough for an outer layer of helium to ignite and start the fusion process without the whole star being destroyed. This theory fits with the star’s age, but it doesn’t seem that V838 Monocerotis had enough mass for this process occur.
  4. Planetary capture: when a star grows to large proportions, it can start consuming nearby planets. The friction generated when a very large planet gets pulled apart by the star’s gravity can produce enough energy to spark deuterium fusion, which releases massive amounts of energy (like what we see in the time-lapse).
  5. The explosion was a result of a mergeburst. Sometimes, in clusters of younger stars (where orbits can be very unstable), two main-sequence stars can collide, creating an explosion similar to the one in the video. The relatively young age of the stars near V838 Monocerotis make this a reasonable possibility, and this hypothesis has also been supported by computer modeling.

It’s awesome to study the stars and find out exactly why they act the way they do, but sometimes explanations can be elusive. So while we search for answers, we should also make sure we take the time to simply enjoy watching this mesmerizing cosmic phenomenon.

(h/t Gizmodo)

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Astronomers Just Witnessed A Massive Cosmic Explosion… 12 Billion Years After It Happened

Supergiants are massive stars with huge amounts of energy, which causes them to expand rapidly. However, all stars eventually reach a limit, after which the gravity of the core is no longer able to hold the star together.

The explosion that follows is known as a supernova (or sometimes a hypernova, if it’s big enough). As the outer portions of the star explode off, the core collapses upon itself.

Nebulas are the remnants of a supernova explosion. This is the Crab Nebula. Click to enlarge

If a star is large enough, the extreme amount of energy produced by this inward collapse forces the star’s core to release high-energy gamma particles. These gamma bursts are the most powerful event so far discovered in the universe. But just how powerful is that?

Well, in just 10 seconds, these gamma ray bursts release more energy than our Earth’s sun will during the entire 10 billion years of its expected lifespan.

On April 19th, in the Davis Mountains of West Texas, the ROTSE-IIIb telescope (owned by Southern Methodist University in Dallas) detected the rare phenomenon in a corner of the sky.

Click to enlarge

The gamma ray burst, classified as GRB 140419A by NASA’s Gamma-ray Coordinates Network, came from a supernova that happened 12.1 billion years ago, not long after the Big Bang (estimated to have occurred 13.8 billion years ago).

Gamma ray burst have only recently been observed. Not only are they at extremely high frequencies, but they also have the shortest wavelengths on the electromagnetic spectrum, making them more difficult to detect. It wasn’t until the 90s that we created a telescope with the technology to detect gamma radiation.

The discovery was published in Science Daily earlier this month. You can read the full story here.

NOTE: The feature image is an artist rendering of a gamma burst. It is, however, based on detailed scientific study of the event.

What It Looks Like When Two Neutron Stars Rip Each Other Apart to Form a Black Hole (Video)

A neutron star is what’s left behind when a massive star (typically 8-30 times the size of our Sun) explodes into a supernova. These supergiant stars get so large that they are no longer able to remain stable under their own intense gravity, collapsing in on themselves.

The gravity is so massive that it exceeds the strength of the atomic forces within particles, causing them to eject protons and electrons. The ball of neutrons they leave behind is so dense that a teaspoonful of the material would weigh as much as Mount Everest!

A neutron star (the tiny white dot in the middle) surrounded by the remnants of the supernova explosion that created it. Click to enlarge (Photo: NASA/Andrew Fruchter)

Neutrons stars have a “mass threshold”- if they take on too much mass, even the neutrons themselves will collapse. When two of these extremely dense neutron stars collide, the extra mass they add to one another causes their massive gravitational forces to tear each other apart.

They go into a blindingly-fast death spin, ejecting massive amount of material while merging into a doughnut like structure with a black hole at its center. The entire process takes just 20 milliseconds (that is 1/50th of a second, if you’re wondering).

Check out a simulation of the amazing phenomenon courtesy of NASA:

NASA Explains How a Supernova Generates Such an Intense Explosion with a Simple Exercise (Video)

According to Dictionary.com a supernova is…

“the explosion of a star, possibly caused by gravitational collapse, during which the star’s luminosity increases by as much as 20 magnitudes and most of the star’s mass is blown away at very high velocity, sometimes leaving behind an extremely dense core.”

Not only are supernovas an interesting and cool concept but, supernovas are an important process in our solar system, galaxy, and universe. In fact, supernovas have had a large influence in shaping our solar system and galaxy.

Below is a simple video by NASA that helps explain and show the concept behind why supernovas create such a high velocity explosion.