Two ‘super-luminous’ supernovae — stellar explosions 10–100 times brighter than other supernova types — have been detected in the distant Universe, using the W.M. Keck Observatory on the top of Mauna Kea in Hawaii. The discovery, reported online in Nature this week, sets a record for the most distant supernova yet detected, and offers the rare possibility of observing the explosions of the first stars to form after the Big Bang.
Simulation of a galaxy hosting a super-luminous supernova and its chaotic environment in the early Universe. Credit: Adrian Malec and Marie Martig (Swinburne University)“The type of supernovae we’ve found are extremely rare,” said Jeff Cooke, astrophysicist at Swinburne University of Technology, whose team made the discovery. “In fact, only one has been discovered prior to our work. This particular type of supernova results from the death of a very massive star (about 100 – 250 times the mass of our Sun) and explodes in a completely different way compared to other supernovae. Discovering and studying these events provides us with observational examples to better understand them and the chemicals they eject into the Universe when they die.”
Super-luminous supernovae were discovered only a few years ago, and are rare in the nearby Universe. Their origins are not well understood, but a small subset of them is thought to occur when extremely massive stars undergo a nuclear explosion triggered by the conversion of photons into electron–positron pairs. Such events are expected to have occurred more frequently in the early Universe (at high redshift), when massive stars were more common. This, and the extreme brightness of these events, encouraged Cooke and colleagues to search for super-luminous supernovae at redshifts, z, greater than 2, when the Universe was less than one-quarter of its present age.
The W. M. Keck Observatory seeks a Senior Mechanical Engineer to work under the direction of the TSD Senior Engineer to provide mechanical engineering and project management support, to develop new observatory capabilities and to upgrade existing observatory systems. This position is responsible for design, analysis, specification, and construction of high technology mechanical and opto-mechanical systems for precision telescope operations.
the segment crane being lowered into place to remove a segment from a primary mirrorQualifications for this position are:
B. S. Mechanical Engineering or equivalent.
>8 years of Mechanical Engineering experience, some experience with opto-mechanical devices, 3 years of which are in project/subcontract management and reporting.
Track record of precision designs of small and large scale mechanical components.
Competence with 3D computer aided design, finite element analysis, design for assembly and maintainability, product life cycle management, and reliability engineering.
Engineering process and configuration management experience.
Experienced use of modern manufacturing techniques.
New research using the world’s largest telescope at the Keck Observatory in Hawaii has revealed two distinct populations of star clusters surrounding galaxies that have radically different chemical compositions.
M22 or NGC6656 in Sagittarius, a classic globular clusterAn international team, led by Swinburne astronomers Christopher Usher and Professor Duncan Forbes, has measured the chemical composition of more than 900 star clusters in a dozen galaxies.
“This is ten times the number of star clusters previously examined, allowing us to confirm the existence of two chemically-distinct star clusters,” Mr Usher said.
Dr. Ben Zuckerman
University of California at Los Angeles Violent Events in Rocky Planetary Systems: Implications for the fate of technological civilizations
Looking into the optics of the Keck 2 telescopeThursday, October 25, 2012
7:00 PM
Gates Performing Arts Center Auditorium
Hawaii Preparatory Academy
65-1692 Kohala Mtn. Rd., Waimea
This evening, Dr. Ben Zuckerman of UCLA, will take us on a journey describing Earth’s formation 4.6 billion years ago to its possible demise 4-5 billion years from now. Along the way, we will consider a few tumultuous eras suffered by Earth’s biosphere, including the present. Such eras, from origins to final resting places, can be explored by understanding astronomical studies of other planetary systems. These systems also provide clues for the long-term fate of our technological civilization and the likelihood, or lack thereof, of civilizations beyond our own.
Seating is limited to first come, first served.
Doors Open at 6:30 PM
Free and Open to the Public
A joint effort of citizen scientists and professional astronomers at W.M. Keck Observatory in Hawaii has led to the first reported case of a Tatooine-like planet orbiting twin suns that in turn is orbited by a second distant pair of stars.
Aided by volunteers using the Planethunters.org website, a Yale-led international team of astronomers using Keck’s 10-meter telescope identified and confirmed discovery of the phenomenon, called a circumbinary planet in a four-star system.
Only six planets are known to orbit two stars, according to researchers, and none of these are orbited by distant stellar companions.
“Circumbinary planets are the extremes of planet formation,” said Meg Schwamb of Yale, lead author of a paper about the system presented Oct. 15 at the annual meeting of the Division for Planetary Sciences of the American Astronomical Society in Reno, Nevada. “The discovery of these systems is forcing us to go back to the drawing board to understand how such planets can assemble and evolve in these dynamically challenging environments.”
An artist’s illustration of PH1, a planet discovered by volunteers from the Planet Hunters citizen science project. PH1, shown in the foreground, is a circumbinary planet and orbits two suns. Credit: Haven Giguere/Yale
Dubbed PH1, the planet was first identified by citizen scientists participating in Planet Hunters, a Yale-led program that enlists the public to review astronomical data from NASA’s Kepler spacecraft for signs of planets. It is the project’s first confirmed planet.
The volunteers, Kian Jek of San Francisco and Robert Gagliano of Cottonwood, Arizona, spotted faint dips in light caused by the planet as it passed in front of its parent stars, a common method of finding extrasolar planets. Schwamb, a Yale postdoctoral researcher, led the team of professional astronomers that confirmed the discovery and characterized the planet, following observations from the Keck telescopes on Mauna Kea, Hawaii. PH1 is a gas giant with a radius about 6.2 times that of Earth, making it a bit bigger than Neptune.
“Planet Hunters is a symbiotic project, pairing the discovery power of the people with follow-up by a team of astronomers,” said Debra Fischer, a professor of astronomy at Yale and planet expert who helped launch Planet Hunters in 2010. “This unique system might have been entirely missed if not for the sharp eyes of the public.”
PH1 orbits outside the 20-day orbit of a pair of eclipsing stars that are 1.5 and 0.41 times the mass of the Sun. It revolves around its host stars roughly every 138 days. Beyond the planet’s orbit at about 1000 AU (roughly 1000 times the distance between Earth and the Sun) is a second pair of stars orbiting the planetary system.
A comprehensive study of hundreds of galaxies observed by the Keck telescopes in Hawaii and NASA’s Hubble Space Telescope has revealed an unexpected pattern of change that extends back 8 billion years, or more than half the age of the universe.
“Astronomers thought disk galaxies in the nearby universe had settled into their present form by about 8 billion years ago, with little additional development since,” said Susan Kassin, an astronomer at NASA’s Goddard Space Flight Center in Greenbelt, Md., and the study’s lead researcher. “The trend we’ve observed instead shows the opposite, that galaxies were steadily changing over this time period.”
Today, star-forming galaxies take the form of orderly disk-shaped systems, such as the Andromeda Galaxy or the Milky Way, where rotation dominates over other internal motions. The most distant blue galaxies in the study tend to be very different, exhibiting disorganized motions in multiple directions. There is a steady shift toward greater organization to the present time as the disorganized motions dissipate and rotation speeds increase. These galaxies are gradually settling into well-behaved disks.
This plot shows the fractions of settled disk galaxies in four time spans, each about 3 billion years long. Credit: Credit: NASA’s Goddard Space Flight Center
Blue galaxies—their color indicates stars are forming within them—show less disorganized motions and ever-faster rotation speeds the closer they are observed to the present. This trend holds true for galaxies of all masses, but the most massive systems always show the highest level of organization.
Researchers say the distant blue galaxies they studied are gradually transforming into rotating disk galaxies like our own Milky Way.
“Previous studies removed galaxies that did not look like the well-ordered rotating disks now common in the universe today,” said co-author Benjamin Weiner, an astronomer at the University of Arizona in Tucson. “By neglecting them, these studies examined only those rare galaxies in the distant universe that are well-behaved and concluded that galaxies didn’t change.”
Watching active volcanic eruptions should be done from a safe distance, and a group of California researchers has figured out how to do it from, ironically, Mauna Kea – one of Earth’s tallest volcanoes – using the W. M. Keck Observatory. Employing an ingenious combination of telescopic surveys and archival data, they have gathered nearly 40 distinct snapshots of effusive (slow) volcanic eruptions and high temperature outbursts on Jupiter’s tiny moon, Io, showing details as small as 100 km (60 miles) on the moon’s surface.
While space-based telescopes were once required for viewing surface details on Io – similar in size to our Moon, but more than 1,600 times distant – adaptive optics (AO), pioneered at Keck, allows teams like that led by Franck Marchis, a researcher at the Carl Sagan Center of the SETI Institute, to collect fascinating data on the wild show from Earth. Marchis presented results from ground-based telescopic monitoring of Io’s volcanic activity over the past decade this week, at the 2012 Division of Planetary Sciences Meeting of the American Astronomical Society.
Erupting volcanoes on Io cannot be seen well from beneath the Earth’s atmosphere using classical astronomical techniques. Io is a relatively small satellite with a 3,600 km diameter, more than 630 million kilometers away. In 1979, Voyager 1 visited the Jovian system, revealing Io’s dynamic volcanic activity from the first close-up pictures of its surface, capturing bizarre volcanic terrains, active plumes and hot spots. The Galileo spacecraft remained in orbit in the Jovian system from 1995 to 2003 and observed more than 160 active volcanoes and a broad range of eruption styles. Several outstanding questions remained in the post-Galileo era, and the origin and long-term evolution of Io’s volcanic activity is still not fully understood.
Quiescent activity of Io observed in 2010 and 2011 showing several quasi-permanent eruptions at 3.8 microns [bottom] and the absence of bright, hotter outbursts at 2.1 microns [top]. Credit: Franck Marchis, SETI Institute
In the meantime, astronomers designed instruments to break the “seeing barrier” and improve the image quality of ground-based telescopes. The blurring (“seeing”) introduced by the constant motion of the Earth’s atmosphere can be measured and corrected in real time using adaptive optics (AO), providing an image with a resolution close to the theoretical “diffraction limit” of the telescope. The W. M. Keck Observatory has used adaptive optics since 1999.
“Since our first observation of Io in 2001 using the Keck II 10-meter telescope and its AO system from Mauna Kea in Hawaii, our group became very excited about the technology. We also began using AO at the Very Large Telescope in Chile, and at the Gemini North telescope in Hawaii. The technology has improved over the years, and the image quality and usefulness of these AO systems have made them part of the essential instrument suite for large telescopes,” said Marchis.
Astronomers using the W. M. Keck Observatory, the Hubble Space Telescope, and other telescopes on Mauna Kea have studied a giant filament of dark matter in 3D for the first time. Extending 60 million light-years from one of the most massive galaxy clusters known, the filament is part of the cosmic web that constitutes the large-scale structure of the Universe, and is a leftover of the very first moments after the Big Bang. If the high mass measured for the filament is representative of the rest of the Universe, then these structures may contain more than half of all the mass in the Universe.
The theory of the Big Bang predicts that variations in the density of matter in the very first moments of the Universe led the bulk of the matter in the cosmos to condense into a web of tangled filaments. This view is supported by computer simulations of cosmic evolution, which suggest that the Universe is structured like a web, with long filaments that connect to each other at the locations of massive galaxy clusters. However, these filaments, although vast, are made mainly of dark matter, which is incredibly difficult to observe.
Reconstruction of a dark matter filament superimposed on the galaxy cluster. Credit: Image by ESA. Additional elements by K. Teramura, Univ. Hawaii Institute for Astronomy
The first convincing identification of a section of one of these filaments was made earlier this year. Now a team of astronomers has gone further by probing a filament’s structure in three dimensions. Seeing a filament in 3D eliminates many of the pitfalls that come from studying the flat image of such a structure.
“Filaments of the cosmic web are hugely extended and very diffuse, which makes them extremely difficult to detect, let alone study in 3D,” says Mathilde Jauzac (LAM, France and University of KwaZulu-Natal, South Africa), lead author of the study.
The team combined high resolution images of the region around the massive galaxy cluster MACS J0717.5+3745 (or MACS J0717 for short), taken using Hubble, NAOJ’s Subaru Telescope and the Canada-France-Hawaii Telescope, with spectroscopic data on the galaxies within it from the W. M. Keck Observatory and the Gemini Observatory. Analyzing these observations together gives a complete view of the shape of the filament as it extends out from the galaxy cluster almost along our line of sight.
The planet Uranus, known since Voyager’s 1986 flyby as a bland, featureless blue-green orb, is beginning to show its face.
By using a new technique with the telescopes of the Keck Observatory, astronomers have created the most richly detailed, highest-resolution images ever taken of the giant ice planet in the near infrared, revealing an incredible array of atmospheric detail and more complex weather.
The planet, in fact, looks like many of the solar system’s other large planets — the gas giants Jupiter and Saturn, and the ice giant Neptune — said Imke de Pater, professor and chair of astronomy at the University of California, Berkeley, and one of the team members. The planet has bands of circulating clouds, massive swirling hurricanes and an unusual swarm of convective features at its north pole.
“This ‘popcorn’ appearance of Uranus’s pole reminds me very much of a Cassini image of Saturn’s south pole,” said de Pater.
The two faces of Uranus as seen through the adaptive optics on the near-infrared camera of the Keck II telescope in Hawaii. Credit: Lawrence Sromovsky, Pat Fry, Heidi Hammel, Imke de Pater.
Saturn’s south pole is characterized by a polar vortex or hurricane, surrounded by numerous small cloud features that are indicative of strong convection and analogous to the heavily precipitating clouds encircling the eye of terrestrial hurricanes. De Pater’s group suggested that a similar phenomenon would be present on Neptune, based upon Keck observations of that planet.
“Perhaps we will also see a vortex at Uranus’ pole when the pole comes in full view,” she said.
The study was led by Larry Sromovsky, a planetary scientist at the University of Wisconsin, Madison. In addition to de Pater, other team members are Pat Fry of the University of Wisconsin and Heidi Hammel of the Association of Universities for Research in Astronomy. The team will report the details of their observations Oct. 17 at a meeting of the American Astronomical Society’s Division of Planetary Sciences in Reno, Nev.
Dr. Ben Zuckerman
University of California at Los Angeles Violent Events in Rocky Planetary Systems: Implications for the fate of technological civilizations
Looking into the optics of the Keck 2 telescopeThursday, October 25, 2012
7:00 PM
Gates Performing Arts Center Auditorium
Hawaii Preparatory Academy
65-1692 Kohala Mtn. Rd., Waimea
This evening, Dr. Ben Zuckerman of UCLA, will take us on a journey describing Earth’s formation 4.6 billion years ago to its possible demise 4-5 billion years from now. Along the way, we will consider a few tumultuous eras suffered by Earth’s biosphere, including the present. Such eras, from origins to final resting places, can be explored by understanding astronomical studies of other planetary systems. These systems also provide clues for the long-term fate of our technological civilization and the likelihood, or lack thereof, of civilizations beyond our own.
Seating is limited to first come, first served.
Doors Open at 6:30 PM
Free and Open to the Public
