milky way •

Milky Way Might Be Dying but There Is a Cure

January 31, 2016 By Chen Lai Leave a Comment

Our galaxy is either dying or already dead, but the Smith Cloud might revive it.

Latest astronomical measurements established that the Milky Way might be dying but there is a cure in the form of a gas cloud that is approaching our galaxy.

A professor at the Zurich Institute of Technology from Switzerland, Kevin Schawinski started a collaboration with other scientists in order to begin the work on a classification of galaxies, especially focusing on their shape.

According to their findings, the shape of a galaxy can determine its lifespan. After applying the new information on the Milky Way, the scientists discovered that there are two possibilities either the galaxy is shutting down slowly, or it has already died and we are living in a sort of zombie galaxy.

The Milky Way might be dying but there is a cure. A galaxy feeds on hydrogen gas, and the astronomers have found a huge cloud of the desired gas heading our way. This could revive the Milky Way, extending its life expectancy with a few more billion years.

The hydrogen gas is needed because it is the raw material from which stars are formed. When a galaxy runs out of hydrogen gas, the process that allows stars to be formed is ceased. And seen as stars have a limited life span, a galaxy will only continue to survive for as long as the hydrogen burning giants continue to burn. After that, all of the stars that will die will collapse and form a black hole which will slowly engulf the entire galaxy.

There are three different color codes when it comes to categorizing a galaxy. The blue galaxies which are young, and the majority of the stars are still forming, the red galaxies in which a great part of the stars are already formed, and the green galaxies which that are on the brink of death. The Milky Way falls into the third category.

But fear not, Milky Way might be dying but there is a cure and it was captured by the Hubble Telescope not long ago. The cloud of hydrogen gas that is traveling at a high speed and heading right towards our galaxy was named the “Smith Cloud”.

According to the scientists, the cloud may have been a part of the Milky Way 70 million years ago, and now the prodigal cloud –son returns just in time after gathering enough helium and hydrogen to help the mother galaxy give birth to approximately 2 new million suns.

The cloud is an important example of how galaxies change over time. Milky Way might be dying but there is a cure, the galaxy just has to hang on a couple dozen million years or so.

The Smith Cloud is estimated to reach the Milky Way in almost 30 million years.

Image source: www.flickr.com

Here’s Why Milky Way’s Supermassive Black Hole Didn’t Gobble

November 5, 2014 By Jason Leathers 2 Comments

A celestial object known as ‘G2’, believed to be a cloud of hydrogen gas was discovered by researchers in 2003. However, earlier this year, it had a close encounter with a supermassive black hole at the center of the Milky Way.

The astronomers were quite excited about this phenomenon because this would eventually enable them to see the huge gas cloud being gobbled up by the black hole called Sagittarius A*.

In contrast to what the astronomers expected, however, G2 was not smashed during its encounter with the black hole, and a recent study reveals an authentic explanation why.

Andrea Ghez from the department of physics and astronomy at the University of California, Los Angeles (UCLA), and colleagues said that, “the reason G2 proceeded intact after its encounter with the black hole is that it is not actually a cloud of hydrogen gas at all.” The study is published on 3^rd November in the Astrophysical Journal Letters.

The researchers claimed that if G2 had been a hydrogen gas cloud as initially assumed, it could have been torn apart by Sagittarius A* that would have produced celestial fireworks.

Ghez said, “G2 survived and continued happily on its orbit; a simple gas cloud would not have done that. G2 was basically unaffected by the black hole. There were no fireworks.”

The researchers conducted a detailed study of G2 with the help of the world’s largest optical and infrared telescopes at the W.M. Keck Observatory in Hawaii and suggested that G2 is probably a pair of stars.

The binary star system had been orbiting the black hole together and then merged to become an extremely large star enveloped in the dust and gas with its movement being influenced by the powerful gravitational field of the black hole, Ghez and colleagues claimed.

Similarly, the researchers noted that G2 seemed to be one of a rising class of stars close to the black hole, which were created due to the powerful gravity of the black hole causing the binary stars to merge into one.

“G2 is a dusty red object linked with gas that reveals tidal interactions as it’s next to its closest approach to the Galaxy’s central black hole. We propose that G2 is a binary star merger product and will ultimately appear similar to the B-stars that are tightly clustered around the black hole (the so-called S-star cluster),” researchers wrote.

Astronomers Discovered Supermassive Black Hole Absorbs Galaxy

September 19, 2014 By Rebecca McGhee 1 Comment

As galaxy’s go, the one we live in, The Milky Way, is estimated at being 100,000 light years in width. For the uninitiated a light year is the distance light can travel in one year. Light being the fastest thing in our universe we know of, that means if one had a ship that could travel as fast as light, it would take them 100,000 years to transverse the Milky Way. Not all galaxies are the same as some are different sizes and make up different configurations but it’s often to find a black hole in the middle of a galaxy. Our galaxy has a black hole as big as 4.1 million of our Suns in power.

In the case of a new galaxy studied called M60-UCD1, a dwarf galaxy, is 300 light years in diameter. The surprising thing is the massive black hole found inside this galaxy that is five times the size of the black hole in the center of our galaxy. This suggests similar dwarf galaxies may hold supermassive black holes as well. Scientists speculate that such galaxies like M60-UCD1 may have been part of another galaxy that was stripped of its stars. Perhaps also there may have been collisions of some sort.

Anil Seth, Astronomer, and lead author of the international study of this dwarf galaxy had his findings published on September 18, 2014 in the journal “Nature”. He said in the piece, “We don’t know of any other way you could make a black hole so big in an object this small.”. His team of astronomers utilized the tools of the Hubble Space Telescope and in addition the Gemini North 8-meter optical and infrared telescope located on Hawaii’s Mauna Kea to examine M60-UCD1 and get the measurements on the black hole’s mass inside. The Hubble provided images that allowed for estimating the galaxy’s diameter as well as stellar density. The Gemini telescope measured the stellar motions as affected by the pull of the black hole’s gravitational field. This information is compiled to calculate the mass of the black hole.

The discovery of such a galaxy and a supermassive black hole like this allows scientists to postulate on other phenomena found in the universe. Looking at the raw data gathered by telescopes and putting together a team of professional astronomers allows for answering questions that have mystified science for centuries. This discovery opens the doors to new clues as to what we’ll find while exploring the heavens.

Categories