Artist's impression of dwarf planet 90377 Sedna that was discovered in 2003. Sedna orbits the sun in the outer solar system, a region that is thought to contain many more as yet to be discovered trans-Neptunian objects. The discovery of 2012 VP 2113 now adds to the tally of mysterious outer-solar system class of planetary bodies.
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.
After a decade of searching, astronomers have found a second dwarf-like planet far beyond Pluto and its Kuiper Belt cousins, a presumed no-man’s land that may turn out to be anything but.
How Sedna, which was discovered in 2003, and its newly found neighbor, designated 2012 VP 2113 by the Minor Planet Center, came to settle in orbits so far from the sun is a mystery.
Sedna comes no closer than about 76 times as far from the sun as Earth, or 76 astronomical units. The most distant leg of its 11,400-year orbit is about 1,000 astronomical units.
Newly found VP 2113’s closest approach to the sun is about 80 astronomical units and its greatest distance is 452 astronomical units. The small world is roughly 280 miles (450 kilometers) wide, less than half the estimated diameter of Sedna.
Neither body can be explained by the present structure of the solar system, with its four rocky planets, four outer gas giant planets, disk of small icy Kuiper belt objects beyond Neptune and the comet-rich spherical Oort Cloud located some 10,000 times farther from the sun than Earth.
“Something else earlier on in the history of the solar system had to put them on these orbits,” astronomer Megan Schwamb, with Academia Sinica in Taipei, Taiwan, wrote in an email to Discovery News.
One theory is that a sister star to the sun, jointly incubated in a long-disbanded stellar nursery, gravitationally nudged some of the bodies in the Oort Cloud inward, creating a new and stable orbital subdivision.
Option two is that another planet at least as big as Earth got booted out of the solar system, taking with it a clutch of Kuiper Belt objects into far more distant orbits.
That renegade planet could have left the solar system – or may still be in orbit today.
Astronomers suspect several Earth-mass sized planets formed in the giant planets region.
“What happened to those objects – if they collided with the giant planets and eventually became a part of the giant planets, or if they got ejected – is not known,” astronomer Scott Sheppard, with the Carnegie Institution of Washington DC, told Discovery News.
Some computer models show it was another giant planet that got expelled from the solar system, pulling bodies as it went.
“The bigger the object, the more planets it could pull out to this region,” Sheppard said.
The search for other Sedna-like objects continues. Sheppard and colleague Chad Trujillo with the Gemini Observatory in Hawaii, are working this week to try to confirm six more potential objects discovered last year.
Several observations over a period of at least a year are needed to detect the slight motion of the small, dim targets against background stars.
“It’s like looking out your car window while you’re driving on the highway. Things that are very close move very quickly with respect to the background things and things that are more distant, like mountains, move slowly. The technique is to basically to look for objects that move with respect to the background stars, but move very slowly. The slower they move, the farther away they are,” Trujillo said.
Ultimately, scientists suspect the population of Sednas could outnumber their Kuiper Belt cousins, making them the second largest collection of bodies after the planets that are in stable orbits around the sun.
The research appears in this week’s Nature.