(Source: Space.com)
A recent photo of the colossal Centaurus A galaxy pierces through thick clouds of cosmic dust to reveal a clear view of its bright galactic center.
The image was taken by the European Southern Observatory (ESO)’s Atacama Large Millimeter/submillimeter Array, or ALMA, the world’s most complex collection of ground-based radio telescopes located in the Chilean Andes. To lift the veils of dust that obscure Centaurus A’s central band, astronomers observed the galaxy in longer wavelengths of radiation than optical light.
The photo, which was released on May 31, combines observations from ALMA at around one millimeter, and other views in near-infrared light from the SOFI instrument, which is attached to the ESO NewTechnology Telescope at the La Silla Observatory in Chile.
The result is a clear look at the galaxy’s brilliant center, where a supermassive black hole with a mass 100 million times heavier than the sun resides.
Centaurus A is a sprawling elliptical galaxy that emits strong radio waves, and is the nearest and most prominent radio galaxy in the sky. The galaxy is located approximately 12 million light-years away from Earth in the southern constellation of Centaurus (The Centaur).
Centaurus A has been an intriguing target for astronomers, who have observed the massive galaxy using different telescopes at a variety of wavelengths. In visible light, Centaurus A’s characteristic dark central band obscures many features at its heart. This prominent lane of gas and dust is also a hotbed of young stars.
The galaxy’s dusty central band and its strong radio emissions indicate that Centaurus A is likely the product of a collision between a massive elliptical galaxy and a smaller spiral galaxy. The dusty band is likely the remains of the smaller galaxy that is being ripped apart by the gravitational pull of the more massive elliptical galaxy, ESO scientists said in a statement.
In the new photo, measurements from ALMA appear as shades of green, yellow and orange. These views map the position and motion of Centaurus A’s clouds of gas, and they are among the sharpest and most sensitive observations of these features ever made, ESO officials said.
ALMA was used to detect signals emitted by molecules of carbon monoxide gas at wavelengths around 1.3 millimeters. The motion of the gas in the galaxy causes slight changes to this wavelength, which can be seen in the slight changes of color in the image.
Gas moving toward us appears green, while the orange colors show gas moving away. Since gas to the left of the center is moving toward us, and gas to the right of the center is moving away, these clouds appear to be orbiting around the galaxy.
M106- A spiral galaxy located 21 million light years away in the constellation Ursa Major. It is approximately 30,000 light years in diameter. A particularly striking feature shows that M106 has jets of glowing hydrogen gas, seen in pink. M106 is also an active spiral galaxy, meaning that it most likely contains a supermassive black hole in the center.
Spiral galaxy, M81. Located 11.8 million light years from Earth in the constellation of Ursa Major.
M83- Black hole outburst observed by Chandra
Scientists using the Chandra X-Ray Observatory have seen a remarkable outburst of X-rays from an old Black hole inside the M83 Spiral Galaxy.The photo on the top is an optical image of spiral galaxy M83 from the Very Large Telescope in Chile, and the pinky cutout to the right is a composite of the optical and X-ray Photos. The data shows a massive increase in X-Ray output in a particular area. These outbursts are called ULXs (Ultraluminous X-Ray Sources) and this is one of the first times that a change of this magnitude has been observed in a binary system (companion star orbiting a neutron star, or black hole) The brightness of the ULX inside M83 increased by 3000%. This is evidence (along with a similar outburst inside M31) for lower-mass black holes which are more volatile than previously thought. The optical data shows a bright blue source (pictured bottom) which astronomers believe to be a disk of energetic material around the black hole which was picked up by its companion star.
Andromeda Galaxy- Our Milky Way galaxy will no longer take the shape of a barred, spiral galaxy when the enormous Andromeda Galaxy merges with us. Andromeda currently lies approximately 2.6 million light years away and is heading towards our galaxy at around 80 miles per second. I wouldn’t worry just yet as this collision will take place in 3.5 billion years; that’s how far away Andromeda is. It’s size is estimated to be around 200,000 light years in diameter and is measured to contain nearly one trillion stars. By comparison, our own galaxy probably has close to 400 billion stars. This picture beautifully shows the center of the Andromeda surrounded by hot blue stars, which are usually very massive and have short lives. Just like our own galaxy, it is believed that at the center of Andromeda lies a supermassive black hole. Imagine a region of space only 5 light years in diameter (Roughly the distance to the nearest star, Alpha Centauri), that contains the mass of 10 million stars. This enormous amount of mass can not be explained by what is seen visually through stars, gas and dust. Measuring stars near the core of active galaxies has proven that those stars nearest the core are orbiting “something” at speeds near 3,000 miles per second. For contrast, our sun orbits the center of the Milky Way at 135 miles per second. The numbers sort of speak for themselves and further proves the existence of supermassive black holes in the center of galaxies such as our Milky Way and the Andromeda galaxies.
Also known as NGC 628, the Messier 74 galaxy is between 24.5 and 36 million light-years away, and has a diameter of about 100,000 light-years. It is suspected to have a black hole at its center, with a mass equal to 10,000 Suns.
This extraordinary feature of nature in the vastness of space shows three galaxies merged together. This combination of galaxies is dubbed, The Bird Galaxy Cluster, but has been noted for its “Tinkerbell-like” appearance. At 650 million light years away, the three galaxies comprise of a barred, spiral galaxy and two irregular galaxies. One of the irregular galaxies is massive and is creating stars at a rapid rate. It is also believed that two galaxies that represent the body of the bird merged together and the “head” part of the bird merged perhaps 200 million years later. This region is where the most stars are being created, an estimated 200 per day!
M51: The Whirlpool Galaxy
Follow the handle of the Big Dipper away from the dipper’s bowl until you get to the handle’s last bright star. Then, just slide your telescope a little south and west and you might find this stunning pair of interacting galaxies, the 51st entry in Charles Messier famous catalog. Perhaps the original spiral nebula, the large galaxy with well defined spiral structure is also cataloged as NGC 5194. Its spiral arms and dust lanes clearly sweep in front of its companion galaxy (top), NGC 5195. The pair are about 31 million light-years distant and officially lie within the angular boundaries of the small constellation Canes Venatici. Though M51 looks faint and fuzzy to the human eye, deep images like this one can reveal the faint tidal debris around the smaller galaxy.
M64 Black Eye Galaxy by Johnny Paglioli on Flickr.
