Question: Which Star is Likely to go Supernova in Our Lifetimes?

Question: I have read that supernovae only happen in our galaxy every hundred years or so, so which star is the most likely candidate to go nova soon? What will it look like from Earth?"

Answer: It"s difficult to be sure exactly which star will be the first to go, but we have a few candidates to consider. The first candidate is one of the brightest stars in the sky. Eta Carinae, as its called, is a heavyweight star located some 7,500 light-years from Earth. Moving onward, we have IK Pegasus, one of two stars in an ill-fated binary system. One of the stars, IK Pegasus A, will soon transform into a red-giant (this transformation marks the beginning of the end for sun-like stars), subsequently transferring matter to its companion white-dwarf, IK Pegasus B. This process will culminate in a type 1a supernova blast.

Of course, we can"t ignore Antares, a super-giant in the constellation of Scorpio. It too has a companion star that will explode in a type 1a blast. Neither of these are more likely to explode than Betelgeuse. (Perhaps if we say it three times, we"ll get to see it in our lifetimes? Beetlejuice, Beetlejuice, Beetlejuice!)

Find out more about the star and how it will look on Earth, here: http://www.fromquarkstoquasars.com/question-which-star-is-likely-to-go-supernova-in-our-lifetimes/

Image Credit: ESO/L. Calçada (Larger image: http://ow.ly/stGvG)

Standard Candles - Measuring Cosmic Distances:

Among the various questions we are often asked about, the one that comes to the forefront of the mind deals with how we accurately estimate how distant objects truly are from us. It"s a difficult task all together since humans are inherently incapable of truly grasping how large the distance that separates the sun from Pluto or the Oort cloud is (not to mention our crappy depth perception) -- let alone trying to wrap your mind around the 4.37 light-year gap separating our solar system and its closest neighbors in the Alpha Centauri system. Then, we must contemplate the vastness of the universe outside of our peripheral view.. like, all of the planetary systems across our galaxy at large and of our local group -- a region of space containing more than 54 galaxies. We know that much more exists beyond our local group, which brings us to the point of this article... how exactly are distances measured? Lets take a look:

First up, Cepheid variable stars: http://www.fromquarkstoquasars.com/measuring-cosmic-distances/

Image Credit: NASA/JPL/Cal-tech

The Formation of Stellar Mass Black Holes: Making energetic destroyers

The formation of a stellar mass black hole is a very chaotic and energetic event. Really though, there isn"t much that involves black holes that isn"t chaotic or energetic. Stellar mass black holes have a minimum mass of around 3.2 times that of our sun (3.2 solar masses). I say "around" because, due to our lack of understanding of neutron degeneracy thresholds, we don"t quite know where the boundary is between neutron stars and black holes. At the moment, 3.2 solar masses is a good guesstimate, as it fits snugly in between the most massive neutron star and smallest black hole ever discovered.

There are three processes that can form a stellar mass black hole; each one is amazing in its own right. Today, we are going to look at comic collisions and epic mergers, and how these processes contribute to the birth of the most destructive objects in the known universe.

Let’s take a look:
http://www.fromquarkstoquasars.com/formation-of-stellar-mass-black-holes-mergers/

Image:
NASA

Astronomy Photo of the Day: 12/18/13 - The Circinus Galaxy

Chandra - along with ESO"s Very Large Telescope Array - spied a bright, variable supernova blast located in a galaxy 12 million light-years away. This image is a composite showing the central region of the galaxy in question, which is typically referred to as the Circinus galaxy.

In the lower right hand corner of the image, the blue source of light is the supernova blast itself (designated "SN 1996cr"). It was originally discovered back in 2001 (though the light from the actual explosion arrived more than a decade before it was even discovered). Despite there being so many stars in the night sky, it"s pretty infrequent that we observe these celestial events in independent galaxies. By some estimations, one should expect to see one supernova explosion once every 50 years per galaxy! The last verified explosion in the Milky Way was observed back in 1604 by the famed astronomer, Johannes Kepler (many other contenders have been noted in recent years though).

Furthermore, some of you may recall the famous supernova SN 1987A, which occurred in a galaxy approximately 160,000 light-years away -- It"s quite similar to supernova SN 1996cr in many ways, but SN 1996cr spits out almost 1000 times more radio and x-ray emissions.

References & Additional Reading: http://www.fromquarkstoquasars.com/astronomy-photo-of-the-day-121813-the-circinus-galaxy/

Image Credit: X-ray (NASA/CXC/Columbia/F.Bauer et al); Optical (NASA/STScI/ UMD/A.Wilson et al.)

The Progenitors of Gamma-Ray Bursts:

As we"ve discussed a lot recently, gamma ray bursts have the tendency to be just as spectacular as supernova blasts, with none of the glory. Yet comparatively, our amount of knowledge about them remains decidedly small. Especially so when dealing with how they form. The firsts of these high energy events were brought to our attention by the Vela-5B Satellite in the early 1970"s. At the time of their discovery, we had a difficult time pinpointing their origin, but over the course of the next few years, we were successful in determining that the events were non-local (meaning, they didn"t originated in, or around the sun). Eventually, it was thought that the detected gamma ray-bursts, or GRBs (what these events were eventually called) had a luminosity of about 10^39 ergs, we now know that this is ~13 magnitudes smaller than the actual intensity. Due to the much lower assumed intensity value, astronomers came to the conclusion that the GRB"s may take place in the accretion disk around a collapsing star.

It"s never THAT easy though. Is it? See how our views have changed over the years: http://www.fromquarkstoquasars.com/the-progenitors-of-gamma-ray-bursts/

Image Credit: NASA (Unedited Version: http://ow.ly/rP9EY)

The Progenitors of Gamma-Ray Bursts:

As we"ve discussed a lot recently, gamma ray bursts have the tendency to be just as spectacular as supernova blasts, with none of the glory. Yet comparatively, our amount of knowledge about them remains decidedly small. Especially so when dealing with how they form. The firsts of these high energy events were brought to our attention by the Vela-5B Satellite in the early 1970"s. At the time of their discovery, we had a difficult time pinpointing their origin, but over the course of the next few years, we were successful in determining that the events were non-local (meaning, they didn"t originated in, or around the sun). Eventually, it was thought that the detected gamma ray-bursts, or GRBs (what these events were eventually called) had a luminosity of about 10^39 ergs, we now know that this is ~13 magnitudes smaller than the actual intensity. Due to the much lower assumed intensity value, astronomers came to the conclusion that the GRB"s may take place in the accretion disk around a collapsing star.

It"s never THAT easy though. Is it? See how our views have changed over the years: http://www.fromquarkstoquasars.com/?p=11511

Image Credit: NASA (Unedited Version: http://ow.ly/rP9EY)

The Progenitors of Gamma-Ray Bursts:

As we"ve discussed a lot recently, gamma ray bursts have the tendency to be just as spectacular as supernova blasts, with none of the glory. Yet comparatively, our amount of knowledge about them remains decidedly small. Especially so when dealing with how they form. The firsts of these high energy events were brought to our attention by the Vela-5B Satellite in the early 1970"s. At the time of their discovery, we had a difficult time pinpointing their origin, but over the course of the next few years, we were successful in determining that the events were non-local (meaning, they didn"t originated in, or around the sun). Eventually, it was thought that the detected gamma ray-bursts, or GRBs (what these events were eventually called) had a luminosity of about 10^39 ergs, we now know that this is ~13 magnitudes smaller than the actual intensity. Due to the much lower assumed intensity value, astronomers came to the conclusion that the GRB"s may take place in the accretion disk around a collapsing star.

It"s never THAT easy though. Is it? See how our views have changed over the years: http://www.fromquarkstoquasars.com/?p=11511

Image Credit: NASA (Unedited Version: http://ow.ly/rP9EY)

The Progenitors of Gamma-Ray Bursts:

As we"ve discussed a lot recently, gamma ray bursts have the tendency to be just as spectacular as supernova blasts, with none of the glory. Yet comparatively, our amount of knowledge about them remains decidedly small. Especially so when dealing with how they form. The firsts of these high energy events were brought to our attention by the Vela-5B Satellite in the early 1970"s. At the time of their discovery, we had a difficult time pinpointing their origin, but over the course of the next few years, we were successful in determining that the events were non-local (meaning, they didn"t originated in, or around the sun). Eventually, it was thought that the detected gamma ray-bursts, or GRBs (what these events were eventually called) had a luminosity of about 10^39 ergs, we now know that this is ~13 magnitudes smaller than the actual intensity. Due to the much lower assumed intensity value, astronomers came to the conclusion that the GRB"s may take place in the accretion disk around a collapsing star.

It"s never THAT easy though. Is it? See how our views have changed over the years: http://www.fromquarkstoquasars.com/?p=11511

Image Credit: NASA (Unedited Version: http://ow.ly/rP9EY)

Activity from Ancient, Invisible Galaxy Observed

Behold, the light of a gamma-ray burst that took place more than 13 billion years ago!

As most of you are aware, the universe is expanding at an ever-increasing speed, which in turn, pushes all galaxies farther away from us. Ultimately, this will result in these galaxies receding so far away, to the point that some of them eventually disappear forever, traveling too fast (located too far away) for their light to ever reach us. However, many of the galaxies that are now too far away were once much closer, offering us an opportunity to study distant, ancient galaxies as they appeared long before our planet was conceived.

s such, astronomers were recently able to detect a destructive event from one such galaxy, located 12.7 billion light-years away. Meaning we are observing the galaxy as it appeared almost 13 billion years ago; basically when the universe was still in diapers, more or less. The galaxy is generally too far away (and too red-shifted as a result of the universe"s expansion) for us to be capable of observing closely

So.. how was this galaxy detected? Find out: http://www.fromquarkstoquasars.com/light-from-an-invisible-galaxy-appears/

Image Credit: Gemini Observatory / AURA / Lynette Cook

We are Starstuff? (Unfinished)

Anyone even remotely interested in astronomy has probably heard someone (perhaps Carl Sagan or Neil deGrasse Tyson) say: "We are star stuff." But what does that mean exactly?

To give a quick breakdown: "Supernovae" occur once a star consumes all of its hydrogen fuel for nuclear fusion, causing the core to contract into a neutron star or a stellar mass black hole. As this happens, the star violently chucks the remainder of its gas off into space in a brilliant explosion that seeds the interstellar medium with heavier elements. Prior to a massive star going supernova (this only occurs with stars that are much more massive than our sun), it would have fused lighter elements (such as hydrogen and helium) into heavier ones (up to and including iron,which is number 26 on the periodic table of elements). And as we all know, iron is in our blood. Hence, our bodies are literally made from the stuff of stars.

To learn all about this process, see:
http://www.fromquarkstoquasars.com/we-are-starstuff-unfinished/

This amazing image comes from:
http://nssdc.gsfc.nasa.gov/photo_gallery/photogallery-astro-nebula.html

The Birth of Gamma-Ray Burst Astronomy:

Gamma-Ray Bursts (GRBs) are some of the most energetic events in the universe. Unsurprisingly, they have been of great interest to the scientific community since their initial discovery in the 1960"s. GRBs are broken up into two types: Short Gamma-Ray Bursts (SGRB) and Long Gamma-Ray Bursts (LGRB). SGRB are observed bursts that are shorter than 2 seconds, and LGRB are observed bursts that are longer than 2 seconds. It was discovered in 1993 that these two subclasses of GRBs existed; however, at that time, the cause of the two different sub types was unknown.

To learn about these GRBs, see:
http://www.fromquarkstoquasars.com/the-birth-of-gamma-ray-burst-astronomy/

Image source:
http://chandra.harvard.edu/photo/printgallery/2004/