Cosmic Hat-Trick: Rare Triple Quasar Discovered!
Andrew Cooper/W. M. Keck Observatory
March 13, 2013, marks 20 years since the W. M. Keck Observatory began taking observations of the cosmos. Located in arguably one of the most extreme and beautiful places on the planet -- atop Mauna Kea, Hawai'i, 13,803 ft (4,207 m) above sea level -- the twin Keck domes have observed everything from asteroids, planets, exoplanets to dying stars, distant galaxies and nebulae. Seen in this photograph, the Keck I and Keck II telescopes dazzle the skies with their adaptive optics lasers -- a system that helps cancel out the turbulence of the Earth's atmosphere, bringing science some of the clearest views attainable by a ground-based observatory.
To celebrate the last two decades of incredible science, Discovery News has assembled some of the most impressive imagery to come from Keck.
William Merline, SWRI / W.M. Keck Observatory
Starting very close to home, the Keck II captured this infrared image of asteroid 2005 YU55 as it flew past Earth on Nov. 8, 2011.
Larry Sromovsky (University of Wisconsin)
Deeper into the solar system, the Keck NIRC2 near-infrared camera captured this beautiful observation of the oddball Uranus on July 11-12, 2004. The planet's north pole is at 4 o'clock.
W.M Keck Observatory/NASA/JPL-G.Orton
This is a mosaic false-color image of thermal heat emission from Saturn and its rings on Feb. 4, 2004, captured by the Keck I telescope at 17.65 micron wavelengths.
Antonin Bouchez (W. M. Keck Observatory)
A nice image of Saturn with Keck I telescope with the near infrared camera (NIRC) on Nov. 6, 1998. This is a composite of images taken in Z and J bands (1.05 and 1.3 microns), with the color scaling adjusted so it looks like Saturn is supposed to look to the naked eye.
Antonin Bouchez, W.M. Keck Observatory
This is Saturn's giant moon Titan -- a composite of three infrared bands captured by the Near Infrared Camera-2 on the 10-meter Keck II telescope. It was taken by astronomer Antonin Bouchez on June 7, 2011.
W. M. Keck Observatory/SRI/New Mexico State University
Another multicolored look at Titan -- a near-infrared color composite image taken with the Keck II adaptive optics system. Titan's surface appears red, while haze layers at progressively higher altitudes in the atmosphere appear green and blue.
Mike Brown, Caltech / W.M. Keck Observatory
This image of Neptune and its largest Tritan was captured by Caltech astronomer Mike Brown in September 2011. It shows the wind-whipped clouds, thought to exceed 1,200 miles per hour along the equator.
A color composite image of Jupiter in the near infrared and its moon Io. The callout at right shows a closeup of the two red spots through a filter which looks deep in the cloud layer to see thermal radiation.
Christian Marois, NRC and Bruce Macintosh, LLNL/W. M. Keck Observatory
HR 8799: Three exoplanets orbiting a young star 140 light years away are captured using Keck Observatory's near-infrared adaptive optics. This was the first direct observation by a ground-based observatory of worlds orbiting another star (2008).
Bob Goodrich, Mike Bolte, and the ESI team
Now to the extremes -- an image of Stephan's Quintet, a small compact group of galaxies.
W.M. Keck Observatory
The Egg Nebula: This Protoplanetary nebula is reflecting light from a dying star that is shedding its outer layers in the final stages of its life.
W. M. Keck Observatory
This is WR 104, a dying star. Known as a Wolf Rayet star, this massive stellar object will end its life in the most dramatic way -- possibly as a gamma-ray burst. The spiral is caused by gases blasting from the star as it orbits with another massive star.
W. M. Keck Observatory/UCLA
Narrow-field image of the center of the Milky Way. The arrow marks the location of radio source Sge A*, a supermassive black hole at the center of our galaxy.
Dr. Mark Morris (UCLA) Keck II, Mirlen instrument
A high resolution mid-infrared picture taken of the center of our Milky Way reveals details about dust swirling into the black hole that dominates the region.
Mansi Kasliwal, Caltech and Iair Arcavi, Weizmann Institute of Science/W. M. Keck Observatory
A false-color image of a spiral galaxy in the constellation Camelopardalis.
A scintillating square-shaped nebula nestled in the vast sea of stars. Combining infrared data from the Hale Telescope at Palomar Observatory and the Keck II telescope, researchers characterized the remarkably symmetrical “Red Square” nebula.
ESA, NASA, J.-P. Kneib (Caltech/Observatoire Midi-Pyrenees) and R. Ellis (Caltech)/W. M. Keck Observatory
Galaxy cluster Abell 2218 is acting as a powerful lens, magnifying all galaxies lying behind the cluster's core. The lensed galaxies are all stretched along the shear direction, and some of them are multiply imaged.
UC Berkeley/NASA/W. M. Keck Observatory
The central starburst region of the dwarf galaxy IC 10. In this composite color image, near infrared images obtained with the Keck II telescope have been combined with visible-light images taken with NASA’s Hubble Space Telescope.
If you’re ever discussing the most dramatic things in the known universe, then quasars should feature quite highly in the conversation. Some of the most distant objects we can see with our most powerful telescopes, these faraway cosmic jewels can shine with the power of a trillion suns. Seeing three of them in the same place is really quite a spectacle!
In fact, it’s an extremely rare spectacle. Quasars are rare objects to begin with. Finding two together is unlikely, let along three!
All the same, that’s exactly what a group of astronomers, led by Emanuele Farina at the University of Insubria in Como Italy, have uncovered — nine billion light years away, known by the ID number of QQQ J1519+0627. A triple quasar system like this is actually so rare that this is only the second one ever to be discovered! Wow!
Quasars are actually the ultraluminous cores of massive galaxies, whose greedy supermassive black holes are gorging themselves on infalling gas and dust. As black holes accrete matter this way, they surround themselves with a huge disk of material.
The colossal gravitational forces at play around a black hole cause tidal heating in disks like this, crushing and squeezing the material in the disk till it reaches extremely high temperatures. Any hapless stars or planets that may venture too near are mercilessly torn asunder. Even the supermassive black hole in our own galaxy is surrounded by corpse-like supernova remnants; stars that strayed too close to the monster.
This superheated disk of crunched up starstuff shines brightly across the entire electromagnetic spectrum, from radio waves through to gamma rays. So intense are the forces which these supermassive black hole accretion disks endure, that they can convert matter into energy more efficiently than the reactions occurring inside stars.
Being 9 billion light-years away, we’re seeing these quasars as they were a long, long time ago. Long before the sun had formed. Probably long before the giant interstellar cloud in which the sun condensed from had formed. The universe was a much younger place back when the light we’re now seeing left those quasars. Younger and smaller, so encounters between multiple objects may have had a greater chance of occurring. Multiple quasars like these are believed to be bound together by gravity, created by galaxies colliding with each other.
In this case, two of the quasars are quite close together, suggesting that they may be interacting. The more distant one, while also gravitationally bound, is less likely to have been involved in the formation of the system.
The only other known triple quasar was discovered as recently as 2007, going by the name of QQQ J1432−0106. At a rather more distant 10.5 billion light years away, it’s been studied well enough to know that these quasars are around 100,000–150,000 light years away from each other. To us, that might sound like they’re rather far apart, but it’s fairly typical for interacting galaxies.
One curious finding with the newest triplet, however, is the lack of ultra-luminous infrared galaxies (ULIRGs) nearby. This is contrary to what might be expected, as quasars and ULIRGs are commonly found in the same neighborhoods. The team that discovered these quasars suggest that this may mean that they’re part of a larger structure which is still forming as we see it.
Michele Fumagalli from Carnegie, one of the astronomers involved in this work, explained in a press release that, “Honing our observational and modeling skills and finding this rare stellar phenomenon will help us understand how cosmic structures assemble in our universe and the basic processes by which massive galaxies form.” Farina also noted that, ”Further study will help us figure out exactly how these quasars came to be and how rare their formation is.”
Image: An image of the three quasars from Calar Alto observatory, combined from Omega 2000 H and z band shots, and SDSS r-band data. The three components (appearing in blue) of the triple quasar QQQ J1519+0627 are identified. Credit: Emanuele Paolo Farina/Calar Alto