Mauna Kea Observatories Put New Spin on Galaxy Formation

W. M. Keck Observatory press release…

A team of Australian researchers used two Maunakea-based observatories – Gemini North and W. M. Keck Observatory – to discover why some galaxies are clumpy rather than spiral in shape and it appears that low spin is to blame. The finding challenges an earlier theory that high levels of gas cause clumpy galaxies, and sheds light on the conditions that brought about the birth of most of the stars in the Universe. The finding was published today in The Astrophysical Journal.

Galaxy Velocity
The massively star-forming galaxies analyzed in this study have clumpy, turbulent gas shown here in false colors. Credit: W. M. Keck Observatory/Gemini Observatory/Hubble
“This result was obtained by a unique and unusual combination of TWO large telescopes,”said Swinburne University astronomer Professor Karl Glazebrook, co-author and leader of the survey team “We used Keck adaptive optics to probe the fine details of galaxy rotation and Gemini to look at the large scale distribution. This made possible a result that was not before known about the spin of early primitive galaxies. It is one of the most exciting results of my career.”

A combination of integral field spectroscopy data from Keck Observatory and Gemini Observatory was the key to obtaining measurements for a galaxy’s spin. Keck Observatory’s OSIRIS instrument collected data high spatial resolution in the galaxy centers, and the Gemini Multi-Object Spectrograph (GMOS) collected data for high surface brightness sensitivity out to large radii.

Lead author Dr. Danail Obreschkow, from The University of Western Australia (UWA) node of the International Centre for Radio Astronomy Research (ICRAR), said that ten billion years ago the Universe was full of clumpy galaxies, but these developed into more regular objects as they evolved; the majority of stars in the sky today, including our five billion-year-old Sun, were probably born inside these clumpy galaxies.

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New Clues to Ceres’ Bright Spots and Origins

NASA/JPL press release…

Ceres reveals some of its well-kept secrets in two new studies in the journal Nature, thanks to data from NASA’s Dawn spacecraft. They include highly anticipated insights about mysterious bright features found all over the dwarf planet’s surface.

Ceres Spots
This false color image from NASA’s Dawn spacecraft of Ceres’ Occator Crater shows differences in surface composition.
Credit: NASA/JPL
In one study, scientists identify this bright material as a kind of salt. The second study suggests the detection of ammonia-rich clays, raising questions about how Ceres formed.

About the Bright Spots

Ceres has more than 130 bright areas, and most of them are associated with impact craters. Study authors, led by Andreas Nathues at Max Planck Institute for Solar System Research, Göttingen, Germany, write that the bright material is consistent with a type of magnesium sulfate called hexahydrite. A different type of magnesium sulfate is familiar on Earth as Epsom salt.

Nathues and colleagues, using images from Dawn’s framing camera, suggest that these salt-rich areas were left behind when water-ice sublimated in the past. Impacts from asteroids would have unearthed the mixture of ice and salt, they say.

“The global nature of Ceres’ bright spots suggests that this world has a subsurface layer that contains briny water-ice,” Nathues said.

A New Look at Occator

The surface of Ceres, whose average diameter is 584 miles (940 kilometers), is generally dark — similar in brightness to fresh asphalt — study authors wrote. The bright patches that pepper the surface represent a large range of brightness, with the brightest areas reflecting about 50 percent of sunlight shining on the area. But there has not been unambiguous detection of water ice on Ceres; higher-resolution data are needed to settle this question.

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New Laser Marks Ground Zero for Adaptive Optics Science

W. M. Keck Observatory press release…

Hawaii’s W. M. Keck Observatory has successfully deployed a $4 million laser system that provides a marked increase in the resolution and clarity of what are already the most scientifically productive telescopes on Earth. The new laser was projected on the sky for the first time on the evening of December 1, 2015 and will allow scientists from around the world to observe the heavens above Maunakea in unprecedented detail.

Keck 2 Lasing
The Keck 2 AO laser works the northern sky
“The Next Generation Laser System is the third generation of lasers at Keck Observatory, which has been pioneering Laser Guide Star Adaptive Optics on big telescopes since 2001,” said Jason Chin, the project manager for the new laser at Keck Observatory.

The first Laser Guide Star Adaptive Optics system on a large telescope was commissioned on the Keck II telescope in 2004 and, among many other firsts, helped reveal the black hole at the center of the Milky Way – one the most significant astronomical discoveries. The second laser system was installed in 2011 on the Keck I telescope, propelling Keck Observatory’s lead as the premiere Adaptive Optics research facility in the world. To date more than 240 science results from these laser systems have been published in astronomical journals.

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NASA Honors Keck Observatory for Opening its Archive to the Public

W. M. Keck Observatory press release…

Keck 2 Lasing
The Keck 2 AO laser works the northern sky
The W. M. Keck Observatory in Hawaii has just been awarded the 2015 NASA Group Achievement Award for pioneering the Keck Observatory Archive (KOA) ten years ago, which has significantly increased the impact of Keck Observatory data. The award was received by Keck Observatory Chief Scientist, Dr. Anne Kinney at NASA headquarters on December 8, 2015.

“For the past 10 years, the NASA KOA team has boosted the science value of data acquired at Keck Observatory by providing the scientific community with open access to WMKO data,” said Mario Perez, Keck Observatory Program Executive at NASA Headquarters in Washington. “They helped set a standard that all new ground based observatories are adopting. For this, the NASA KOA team has earned the NASA Group Achievement Award.”

“We are very proud of this award as well as the KOA project itself,” said Hilton Lewis, Director of W. M. Keck Observatory. “This was the brainchild of Anne Kinney while she was at NASA and who I am happy to report recently joined Keck Observatory as our Chief Scientist. Thanks to her vision, data gathered by all instruments at Keck Observatory is available for everyone to use. The Keck Observatory telescopes are the most scientifically productive on Earth, responsible for gathering data used in about 300 peer-reviewed scientific papers per year – almost one per night. There are terabytes of valuable data collected over the last 20 years waiting to be mined.”

In 2004, NASA established a partnership with WMKO to acquire large volumes of data from a single instrument, the High Resolution Spectrograph (HIRES), for NASA science purposes. It is standard practice to make data from NASA’s space telescopes available to the world in a public archive, but in 2004 it was unheard of to do the same with data from a ground-based telescope. Kinney, then Director of the Astrophysics Division at NASA Headquarters, decided to start a visionary project of promoting public access to these data, and the project began by archiving NASA-acquired HIRES data.

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