Not as big as the Big Bang, but this Big Blast blows away any other explosion ever seen by astronomers. The supermassive black hole at the core of our Milky Way galaxy is generating more heat than expected up to one light-year away (not to worry – it's still 26,000 light years away from earth). And when NASA's MAVEN mission (Mars Atmosphere and Volatile Evolution spacecraft) launches November 14, 2014, you can add your name to those going along on the trip.
May 13, 2013
[Dave Heller] Astronomers are marveling at the largest explosion observed to date. Let's energize with Derrick Pitts, chief astronomer at the Franklin Institute. Derrick, the name Big Bang is spoken for, let's call this the "Big Blast."
[Derrick Pitts] Indeed you could call it a big blast; it's the largest blast of this kind that's ever been seen.
So first off, what was it that exploded and where was it?
Astronomers are surmising that this is the explosion of a star, and the typical format in which stars explode is called supernova. As a star gets on in its age, it has a number of scenarios that will describe its demise. One is that it will eventually become a red, giant star, and after it becomes a red giant star, it can blow off some of its upper layer of gasses and equalize itself and come down to a small, white dwarf. And that's probably most likely what's going to happen to our star. If a star is reasonably bigger than our star, then it can go supernova and blow off almost all of its material leaving only its core.
If a star is even considerably bigger than that, it has the possibility of becoming a supernova, turning into a neutron star, and then ultimately turning into a black hole. Our sun is nowhere near that mass, so we're not going to see that, but stars that are very, very massive in size typically have these explosive ends. So one might reason that if this explosion was so big, it may have been a very big star to begin with.
Sounds like fine reasoning to me.
It does sound like fine reasoning, but problem with the fine reasoning is that we don't really know very much about the star itself. What we know is that there was a large explosion on April 27th large enough that the Swift satellite and the Fermi satellite — both of which are space telescopes that look at gamma ray explosions — detected this, turned toward it and watched it for quite some time. Now, typically an explosion like this, they come in two flavors: there's the short version and there's the long version. The short version of a gamma ray burst, as this is properly called, might be less than two seconds. The long version is two seconds up to several minutes. This was observed at a very high-energy output for HOURS. So it had to be a very intense explosion, very, very high energy, possibly a very large star.
So this released exponentially more energy than anything astronomers had seen to date?
Absolutely, it's the largest explosion that has ever been seen. It lasted long enough that it was not only visible to these space telescopes, but it was also visible to ground-based instruments as well in the infrared spectrum and the visible spectrum. So it really was quite massive of an explosion. One measurement of the energy that was released in one particular instance of a gamma ray that was detected was 35 billion times the amount of energy in visible light. So it would be the king x-ray of x-rays, if you will.
These images show a more detailed Fermi LAT view of GRB 130427A. The frames show high-energy (100 Mev to 100 GeV) gamma rays from a 20-degree-wide region of the sky starting three minutes before the burst to 14 hours after. Following an initial one-second spike, the LAT emission remained relatively quiet for the next 15 seconds while Fermi's GBM instrument showed bright, variable lower-energy emission. Then the burst re-brightened in the LAT over the next few minutes and remained bright for nearly half a day. Credit: NASA/DOE/Fermi LAT Collaboration
Reassure listeners at least that it was safely tucked away in a very distant part of the universe.
Nothing for us to worry about — this was 3.6 billion light years away.
So with that we know when it happened.
Some 3.6 billion years ago, but most interesting: even this is a record because it was one of the closest ever witnessed, one of the closest ever observed, even at 3.6 billion light years away. It still pans out as being one of the closest ever.
Let's come a little closer and also observe a huge energy source right in the middle of our Milky Way.
Yes, even right here we have big stuff going on. One of the other space telescopes in operation over the last little while, the Herschel space telescope, has been able to detect that the supermassive black hole at the core of our galaxy has been doing something that seems to be quite unusual. Now typically, inter-stellar gas even found at the core of galaxies doesn't tend to be very warm, only a few tens of degrees above absolute zero, that's about 459 degrees below zero Fahrenheit. So a few tens of degrees about that might make it minus 400 degrees Fahrenheit. That's still very cold.
What has been observed though by the Herschel telescope is that some of the gas within one light year of the supermassive black hole at the core of our galaxy seems to be running temperatures of 1800 degrees Fahrenheit! Very, very unusual, not expected at all, a real new discovery! And so astronomers speculating about what the possibility might be have come across that notion that perhaps there are interstellar gas clouds at that distance that are colliding with each other. These are highly magnetic interstellar gas clouds; in their collisions, are generating enough energy to drive the temperature up to nearly 2000-degree point.
New meaning for the term "thunderstorm."
Talk about hot gas, this would be the place for hot gas — a thunderstorm for sure! If there were any sound, I think it would be quite impressive. But even at this incredible distance of 26,000 light years away, it's still a safe distance for us. We have nothing to worry about at our position in the galaxy relative to the center of our galaxy where the supermassive black hole is located.
This artist's concept illustrates the frenzied activity at the core of our Milky Way galaxy. A dense torus of gas and dust surrounds the galactic center. Part of this gas is being heated by the strong ultraviolet radiation from massive stars that closely orbit the central black hole. Heating also likely results from strong shocks, generated in collisions between gas clouds, or in material flowing at high speeds. Credit: NASA/JPL
Say, last week you laid out an offer for an enterprise, asking if folks were interested in going to Mars. There was a catch, it was a one-way trip. Now there's a new endeavor and it's somewhat safer.
In case the idea of actually making that one-way trip to Mars didn't really work for you, yes you're right, there is yet another way. NASA has a new mission that's going to launch on November 14 of 2014 called "The MAVEN Mission". This is the Mars Atmosphere and Volatile EvolutioN Mission, and what they're looking for is they're trying to figure out how the early Martian atmosphere, or the loss of the early Martian atmosphere, may have effected what happened to the water on the planet.
Well one of the things that's going to happen along this mission is that NASA is going to allow all of us, all of us out here that provide all the funding for NASA, to go along on the trip in the form of our name. So if you send your name to the MAVEN Mission between now and July 1, your name will be included on the CD that goes to Mars. Now even better, if you think you're sort of a hand at writing poetry, NASA is actually going to select three haiku to be sent as well. Only three. Now there's public voting that will used to select which three will go. The voting begins on July 15. You have to have your submission in for haiku by July 1 along with your name and anyone else's name you'd like to go along with this, and then your haiku might be selected as one of the three that will go to Mars. So this is a fairly safe way to go; it doesn't really involve very much travel, you don't need any seasickness pills or space-sickness pills or anything like that — just send your name off to NASA, it's a very easy process to do.
NASA — MAVEN: Mars Atmospheric Loss