A penumbral lunar eclipse will occur, but it is so minor there is little point in trying to observe it. As the NASA eclipse site notes… “With a penumbral eclipse magnitude  of 0.0158, just 0.5 arc-minutes of the Moon’s southern limb will pass into Earth’s pale penumbral shadow; such a shallow eclipse is only of academic interest since it will be all but impossible to detect.”
Two hungry young galaxies that collided 11 billion years ago are rapidly forming a massive galaxy about 10 times the size of the Milky Way, according to UC Irvine-led research conducted on the W. M. Keck Observatory and other research facilities around the world. The results will be published today in the journal Nature.Capturing the creation of this type of large, short-lived star body is extremely rare – the equivalent of discovering a missing link between winged dinosaurs and early birds, said the scientists, who relied primarily on data from Keck Observatory’s NIRC2 fitted with the laser guide star adaptive optics (LGSAO) system. The new mega-galaxy, dubbed HXMM01, is the brightest, most luminous and most gas-rich submillimeter-bright galaxy merger known.
HXMM01 is fading away as fast as it forms, a victim of its own cataclysmic birth. As the two parent galaxies smashed together, they gobbled up huge amounts of hydrogen, emptying that corner of the universe of the star-making gas.
“These galaxies entered a feeding frenzy that would quickly exhaust the food supply in the following hundreds of million years and lead to the new galaxy’s slow starvation for the rest of its life,” said lead author Hai Fu, a UC Irvine postdoctoral scholar.
The discovery solves a riddle in understanding how giant elliptical galaxies developed quickly in the early universe and why they stopped producing stars soon after. Other astronomers have theorized that giant black holes in the heart of the galaxies blew strong winds that expelled the gas. But cosmologist Asantha Cooray, the UC Irvine team’s leader, said that they and colleagues across the globe found definitive proof that cosmic mergers and the resulting highly efficient consumption of gas for stars are causing the quick burnout.
“Finding this type of galaxy is as important as the discovery of the Archaeopteryx was in understanding dinosaurs’ evolution into birds, because they were both caught at a critical transitional phase,” Fu said.
The new galaxy was initially spotted by UC Irvine postdoctoral scholar Julie Wardlow, also with Cooray’s group. She noticed “an amazing, bright blob” in images of the so-called cold cosmos – areas where gas and dust come together to form stars – recorded by the European Space Agency’s Herschel telescope with important contributions from NASA’s Jet Propulsion Laboratory in Pasadena. “Herschel captured carpets of galaxies, and this one really stood out.”
Follow-up views at a variety of wavelengths were obtained at more than a dozen ground-based observatories, particularly the W.M. Keck Observatory in Hawaii.
“The NIRC2/LGSAO image has revealed the existing stellar population of this pair of galaxies,” Fu said. “The radiation captured by Keck tells us how many stars have already been formed in the system at the observed epoch. These data told us the constituents of the galaxy pair: they are each made of half gas and half stars, which indicates they are nascent galaxies in formation.
The NIRSPEC spectra measured the velocity difference of the two galaxies at only 300 km/s, indicating that the two galaxies are soon to merge instead of just flying by each other. The spectra also show the high-velocity winds driven by the intense star formation in both galaxies, uncovering the violent environment in these galaxies.
UC Irvine graduate student Jae Calanog is co-author of the paper, as are scientists at 27 other institutions in the U.S., Canada, Spain, France, England and South Africa. Funding was provided by NASA.
The W. M. Keck Observatory operates the largest, most scientifically productive telescopes on Earth. The two 10-meter optical/infrared telescopes on the summit of Mauna Kea on the Island of Hawaii feature a suite of advanced instruments including imagers, multi-object spectrographs, high-resolution spectrographs, integral-field spectroscopy and a world-leading laser guide star adaptive optics system. The Observatory is a private 501(c) 3 non-profit organization and a scientific partnership of the California Institute of Technology, the University of California and NASA. Visit keckobservatory.org for more information.
Normally I do not snorkel around the reef, rather I prefer donning full kit including tank and regulator allowing a more immersive experience. Staying down allows me a freedom of movement, to explore well beyond the twenty five feet or so that I can reach without the gear. Scuba permits me to carry a camera with time to compose a subject and observe behavior.But on occasion I hit the water with minimal gear, simply mask and fins Sometimes I am accompanying a friend who is not a qualified diver. Perhaps there is no time or allowance for the large amount of gear scuba required and I simply want to swim. Snorkeling is nice this way, taking a long swim is hardly boring when so much is visible just below.
I skim along, the large fins providing effortless speed. The view is different than that of scuba, you are always looking down. I stay in the shallower water where the coral comes close to the surface. On occasion I dip down below the surface to get a closer look, weaving through the coral on long shallow dives. To go up I simply stop swimming to allow my buoyancy to lift me to the surface. A sharp breath clears the snorkel of water. With practice the actions are almost reflex, as natural as breathing on shore.
There are species that prefer the shallows, rarely seen when diving, often common in just a few feet of water. Snowflake morays, the colorful lagoon triggerfish, snorkeling allows spotting of a different reef community. I often make a point to sweep the areas just off the shore in three feet of water or less, just to see what can be found.
This evening, and the next few evenings, will find Mercury, Venus and Jupiter in a tight triangle just above the sunset. The trio will be separated by less than 3° and will be well above the setting Sun, 14° at sunset, thus will remain in the sky for almost an hour after the Sun slides below the horizon.
Tonight will see Mercury and Venus even closer, separated by only 1°48′, tomorrow that will shrink to 1°26′ and 1°22′ on the 24th. The trio will all be quite bright, with Mercury shining around -1 magnitude, Jupiter at -2, and Venus around -4 magnitude. Keep watching as this trio will continue to be quite close through the end of the month.
Tonight will see a bright Moon just a few degrees from Saturn in the constellation Virgo. The Moon will be nearing full, about 94% illuminated and 4° south of Saturn.
Tonight the Moon will rendezvous with the bright star Spica in the constellation Virgo. The Moon is approaching full, just under 90% illuminated. Evening will see the two quite close, about 2° apart. As the night progresses this separation will diminish as the Moon slides just south of the star. For viewers in Hawai’i the minimum separation will be about 40′ around 2:00 in the morning with the star just 25′ from the Moon’s pole.
I am old enough to remember when a phone book was actually useful. It was the way to locate businesses and the phone numbers of friends. That was a long time ago. At this point I can not remember when I last opened a phone book to accomplish anything useful, an internet search is faster and more informative. A search provides so much more than a phone number…. Business hours, a map to the location with directions if needed, reviews and more. Not to mention that the information is up to date, not printed once a year, a business can update their website as details change. Need to see tonight’s menu?
Phone books are an anachronism from another time, one that belongs in the past. As with any business there is a certain inertia, they will not die quickly. While it does appear that the white pages have properly died, someone needs to put a stake into the yellow pages.
For this household? It is straight into the recycle bin with the book. Unused, unlamented, existing only long enough to inspire a rant.
For the sixth year running I made the drive to Hilo to help in judging the Big Island Regional 2013 MATE Underwater ROV competition. Too much fun to miss!
As usual Keck provided much of the official staff. This is the fault of Keck software engineer Al Honey, the head official, who drafts the rest of us into being there! An engineer from Liquid Robotics and a couple folks from the observatories in Hilo rounded out the judging staff. Add teams from schools all over the island and mix with water to create an event.The missions continue to increase in complexity. This year the task was a simulated undersea research platform. Various instruments were in need of upgrade or servicing. Opening a hatch on the “undersea instrument platform”, disconnecting power, removing an instrument, installing a new instrument, removing bio-fouling, a long list of tasks, each worth a few points in the final tally. Never-mind the instruments were made of PVC and the bio-fouling was actually pipe cleaners, it still was not easy!
I know, I am late to this party. Not unusual, I do not often jump on the latest tech. I still use an iPhone 3GS, only three models back. It was, as usual, my wife who bequested this latest toy upon me. Without her I would be hopelessly out of date.
The GoPro HD Hero 2 camera is interesting to us as it comes with a standard waterproof housing good to scuba depths. The price was right, Deb picked it up as a Costco special.
Thus I attached it to the top of my usual rig to give it a try on a dive or two. As it turns out, it is a good thing I had my regular camera along, there are some issues with a stock GoPro underwater.
The first obvious issue is focus, as I had heard the camera will not focus properly underwater with the standard dome port. The solution to this is to get a flat port.
The more concerning issue is the burned out highlights visible in the video below. This is not unusual in a camera using a typical exposure algorithm designed for daylight above water. Underwater the red light is gone, absorbed by the water. This lack of red creates a tendency for the camera to overexpose the green or blue.
The usual solution is to set a slight under exposure in the scene using exposure compensation. However, the Hero 2 has no exposure compensation control. There are a couple possible solutions… Commonly available is a red filter for the flat port camera. Will this solve the burnouts? Another possibility lies in using a less saturated color profile as available in the new firmware.
While there were issues with the image, the sound seems pretty good for being in a case, much the same as what I hear when diving. The real test would be to dive with a few whales around to see how well it records whalesong. Alas, the humpbacks headed north a couple months ago. I miss the whalesong soundtrack on our dives. A pod of dolphins perhaps?
I plan to set up the GoPro as a stand alone camera and video rig for diving. Just the camera, an Ultralight handle and arm I have on-hand, plus a video light, which I also have on-hand. I just need to manufacture a tray for the setup, another hour in the machine shop. This should make a compact, lightweight dive or snorkeling camera rig.
I can think of a few other interesting uses for the camera, it has some nice timelapse facilities I need to test. Just the camera to use on the top of a boat. The camera does not do low light, just too small a sensor and lens. Still, there are quite a few things it should do well, a fun addition to the kit.