Behind the Scenes at the Keck Telescope

Who knew there were so many moving parts to operate a telescope? This is a great behind the scenes video of what really takes place up at the summit of Mauna Kea in Hawaii. About 125 people work full-time at the Keck Observatory to operate the two ten-meter telescopes. The intricate fine-tuning and elaborate attention to detail is amazing. “Keeping those telescopes on-sky every night is the summit crew of the Operations Department. This video is dedicated to the guys of the Keck daycrew who make it possible,” wrote Keck engineer Andrew Cooper, who compiled this unique and must-watch video. He details the techniques he used at his Vimeo page for this video.

Most Detailed Look Ever Into the Carina Nebula

A broad panorama of the Carina Nebula, a region of massive star formation in the southern skies. This new method of determining the age of stars will help astronomers better understand the process of star formation. Credit: ESO/T. Preibisch
A broad panorama of the Carina Nebula, a region of massive star formation in the southern skies. This new method of determining the age of stars will help astronomers better understand the process of star formation. Credit: ESO/T. Preibisch

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Like finding buried treasure, this new image of the Carina Nebula has uncovered details not seen before. This vibrant image, from ESO’s Very Large Telescope shows not just the brilliant massive stars, but uncovers hundreds of thousands of much fainter stars that were previously hidden from view. Hundreds of individual images have been combined to create this picture, which is the most detailed infrared mosaic of the nebula ever taken and one of the most dramatic images ever created by the VLT.

A color composite in visible light of the Carina Nebula. Credit: ESO/Digitized Sky Survey 2. Acknowledgment: Davide De Martin.

Although this nebula is spectacular when seen through telescopes, or in normal visible-light pictures, many of its secrets are hidden behind thick clouds of dust. Using HAWK-I infrared camera along with the VLT, many previously hidden features have emerged from the murk. One of the main goals of the astronomers, led by Thomas Preibisch from the University Observatory, Munich, Germany, was to search for stars in this region that were much fainter and less massive than the Sun. The image is also deep enough to allow the detection of young brown dwarfs.

The dazzling but unstable star Eta Carinae appears at the lower left of the new picture. This star is likely to explode as a supernova in the near future, by astronomical standards. It is surrounded by clouds of gas that are glowing under the onslaught of fierce ultraviolet radiation. Across the image there are also many compact blobs of dark material that remain opaque even in the infrared. These are the dusty cocoons in which new stars are forming.

The Carina Nebula lies about 7,500 light-years from Earth in the constellation of Carina.

This video zooms in on the new infrared view of the Carina Nebula:

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Source: ESO

Iconic Telescope Array Gets a New Name

VLA at twilight. Image by Dave Finley, courtesy of NRAO/AUI

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The pop culture-rich Very Large Array has been updated with state-of-the-art technology and to befit the VLA’s new capabilities, the National Radio Astronomy Observatory (NRAO) has given it a new name. Recall, back in October 2011, the NRAO asked for the public’s help in choosing a new name, and 17,023 people from 65 different countries responded by sending 23,331 suggestions.

The new name for the world’s most famous radio telescope is the “Karl G. Jansky Very Large Array” to honor the founder of radio astronomy. Radio astronomy enables the study of the Universe via radio waves naturally emitted by objects in space.

The VLA has been part of movie plots, is on album covers, in comic books and video games. It has now been transformed from its original 1970s-vintage technology with the latest equipment, and the NRAO says that the upgrades will greatly increase the VLA’s technical capabilities and scientific impact.

The new name was announced at the American Astronomical Society’s meeting in Austin, Texas. The new name will become official at a re-dedication ceremony at the VLA site in New Mexico on March 31, 2012.

Karl G. Jansky. Credit: NRAO/AUI/NSF

Karl Guthe Jansky (1905-1950) joined Bell Telephone Laboratories in 1928, and was assigned the task of studying radio waves that interfered with the recently-opened transatlantic radiotelephone service.

He designed and built advanced, specialized equipment, and made observations over the entire year of 1932 that allowed him to identify thunderstorms as major sources of radio interference, along with a much weaker, unidentified radio source. Careful study of this “strange hiss-type static” led to the conclusion that the radio waves originated from beyond our Solar System, and indeed came from the center of our Milky Way Galaxy.

His discovery was reported on the front page of the New York Times on May 5, 1933, and published in professional journals. Janksy thus opened an entirely new “window” on the Universe. Astronomers previously had been confined to observing those wavelengths of light that our eyes can see.

NRAO officials say the new name recognizes the VLA’s dramatic new capabilities and its promise for important scientific discoveries in the future.

“When Karl Jansky discovered radio waves coming from the center of the Milky Way Galaxy in 1932, he blazed a scientific trail that fundamentally changed our perception of the Universe. Now, the upgraded VLA will continue that tradition by equipping scientists to address outstanding questions confronting 21st-Century astronomy,” said NRAO Director Fred K.Y. Lo.

“It is particularly appropriate that the upgraded Very Large Array honor the memory and accomplishments of Karl Jansky,” Lo explained, adding that “the new Jansky VLA is by far the most sensitive such radio telescope in the world, as was the receiver and antenna combination that Jansky himself painstakingly developed 80 years ago.”

Lo said they deeply appreciate all the suggestions for a new name, as well as the strong public interest in the VLA and in astronomy. “There was a tremendous amount of thought and creativity that went into the numerous submissions,” he said. “In the end, we decided it was most appropriate to name the telescope after a genuine pioneer who took the first step on the road that led to this powerful scientific facility,” he said.

The Jansky VLA is more than ten times more sensitive to faint radio emission than the original VLA, and covers more than three times more radio frequency range. It will provide astronomers the capability to address key outstanding scientific questions, ranging from the formation of stars and planets in the Milky Way and nearby galaxies, to mapping magnetic fields in galaxies and clusters, and imaging the gas that forms the earliest galaxies.

Our Picks of Best Space and Astronomy Images from 2011

First Ever Portrait of the International Space Station and docked Shuttle Endeavour from Soyuz capsule. This image of the International Space Station and the docked Space Shuttle Endeavour, flying at an altitude of 220 miles was taken by Expedition 27 crew member Paolo Nespoli from the Soyuz TMA-20 following its undocking on May 23, 2011. It is the first-ever image of a space shuttle docked to the International Space Station. Endeavour at left. European ATV cargo carrier at right. Credit: NASA/Paolo Nespoli

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2011 was a picturesque year! The year brought us new discoveries, a new supernova, the end of an era in human spaceflight, and much more. Here’s a look back at some of the best images we’ve posted on Universe Today in 2011, listed in no particular order:

Above, is one of the first-ever images of a space shuttle docked to the International Space Station. The images were taken by ESA astronaut Paolo Nespoli on May 23, 2011 through a window inside the Soyuz TMA-20 vehicle as he and two crewmates were departing the ISS for their return trip to Earth. See the entire gallery of images of this event here.


Astrophoto: Supernova PTF11kly in M101 by Rick Johnson
Supernova PTF11kly in M101. Credit: Rick Johnson

A new supernova showed up in 2011 in the Pinwheel galaxy, and skywatchers around the world tried to capture it. Amateur astronomer Rick Johnson submitted this image for our new “Astrophoto” feature this year on Universe Today. Called the SN PTF11kly, the new Type Ia supernova was spotted by Caltech’s Palomar Transient Factory (PTF) survey in the M101, and is located 21 million light years away. You can see the supernova marked in the southern part of the galaxy.

Atlantis launches one last time on July 8, 2011. Credit: Alan Walters (awaltersphoto.com) for Universe Today.

2011 saw the end of an era: the space shuttle program is now history. Universe Today photographer Alan Walters captured this stunning view of the last shuttle launch ever. Read our articles about the final launch and landing of the space shuttle era.

A portion of the Lagoon nebula imaged by the Gemini South telescope with the Gemini Multi-Object Spectrograph. Credit: Julia I. Arias and Rodolfo H. Barbá Departamento de Física, Universidad de La Serena (Chile), and ICATE-CONICET (Argentina).

A gorgeous new look at the “Southern Cliff” in the Lagoon Nebula from the Gemini South Observatory.

Saturns moons and rings, in color. Credit: NASA / JPL / SSI. Edited by Jason Major. Click for larger version.

The Cassini spacecraft continues to crank out spectacular images, and this stunning image of a “flash mob” of moons strung along Saturn’s rings is just an example.

ATV2 (Johannes Kepler) as it departs the ISS against the backdrop of Earth. Credit: NASA/Ron Garan

Real image or from a movie? The ATV-2 Johannes Kepler looks like an X-Wing fighter from Star Wars as it departed from the International Space Station.

A new image from the HiRISE camera on the Mars Reconnaissance Orbiter shows an ethereal landscape near Mars north pole. Credit: NASA/HiRISE team

Incredible landscapes are specialties of the HiRISE camera on the Mars Reconnaissance Orbiter, and this observation shows dune gullies laced with beautiful swirls of tracks left by dust devils. Just like on Earth, dust devils move across the Martian surface and expose the underlying darker material, creating a striking view.

A new image from ESO of the reflection nebula Messier 78. Credit: ESO and Igor Chekalin

Here’s a “Hidden Treasure” from the European Southern Observatory, from the astrophotography competition where amateurs create images from unused ESO data. In this new image of Messier 78, brilliant starlight ricochets off dust particles in the nebula, illuminating it with scattered blue light and creating what is called a reflection nebula.

Series of transits taken on May 20, 22 and 23, 2011 from different areas of France, showing variations of orientation of the ISS with Endeavour docked. On May 23, the ISS passes besides a sunspot which is larger than the Earth. Credit: Thierry Legault

This series of images is just an example of the great work by award-winning French astrophotographer Thierry Legault. During shuttle Endeavour’s final mission, Legault traveled through Germany, France and Spain to find clear skies and good seeing to capture the shuttle’s voyage to the International Space Station. See more incredible images here.

The 'Rock Garden' at the rim of Endeavour Crater on Mars as seen by the Opportunity rover. Credit: NASA/JPL/Caltech, color by Stu Atkinson

The Opportunity rover is now exploring Endeavour Crater and this color view of shows a stunning landscape on Mars. This view of a Red Planet “rock garden” is the colorized handiwork of Stu Atkinson, a member of Unmanned Spaceflight and author of the Road to Endeavour blog. This is actually an ejecta field of rocks thrown about after the impact that created this huge crater, and has been an exciting region for the MER scientists to explore.

Dense filaments of gas in the IC5146 interstellar cloud. This image was taken by ESA’s Herschel space observatory at infrared wavelengths 70, 250 and 500 microns. Stars are forming along these filaments. Credits: ESA/Herschel/SPIRE/PACS/D. Arzoumanian (CEA Saclay) for the “Gould Belt survey” Key Programme Consortium.

Its true there is no sound in empty interstellar space, but the Herschel space observatory has observed the cosmic equivalent of sonic booms. Filaments like this have been sighted before by other infrared satellites, but they have never been seen clearly enough to have their widths measure.

A huge and spectacular prominence eruption on the Sun, June 7, 2011. Credit: NASA/Solar Dynamics Observatory

On June 7, 2011 an amazingly massive and spectacular event took place on the Sun: a huge prominence eruption, marked by a solar flare and release of energetic particles. It was an event that was heretofore unseen on the Sun, but the Solar Dynamics Observatory saw it all.

A view of a recent aurora from the ISS. Credit: NASA

With the Sun’s activities ramping up, we saw more aurorae. What better place to see them than from the International Space Station? This view taken by astroanut Mike Fossum shows a stunning aurora, with two Russian vehicles docked to the station in the foreground.

The star cluster NGC 2100 in the Large Magellanic Cloud. Credit: ESO

A brilliant cluster of stars in the Large Magellanic Cloud, open cluster NGC 2100 shines brightly, competing with the nearby Tarantula Nebula for bragging rights in this image from ESO’s New Technology Telescope (NTT).

Martian Vista from Opportunity nearing Endeavour Crater on Sol 2678 - August 2011 Large ejecta blocks from the nearby, small Odyssey crater are visible in the middle, foreground and are Opportunity’s next science target in this photo mosaic taken 2 martian days ago on Sol 2678 (Aug. 6). Opportunity is now less than 400 feet from the foothills of Endeavour Crater and will soon make first landfall at Spirit Point - off to the left. At Endeavour, Opportunity will investigate the oldest minerals deposits she has ever visited from billions of years ago and which may hold clues to environments that were potentially habitable for microbial life. This photo mosaic shows portions of the discontinuous crater rim – Cape Tribulation at right. Mosaic Credit: NASA/JPL/Cornell/Marco Di Lorenzo/Kenneth Kremer

Universe Today’s Ken Kremer helped bring this stunning image of the hills around Endeavour Crater to light, as the Opportunity Rover headed towards the crater in August.

Astrophoto: Moon Covers Venus by Kevin Jung
Moon Covers Venus. Credit: Kevin Jung

Another amateur astrophoto shows an occultation of Venus by the Moon, taken by Kevin Jung.

X-ray Image of Tycho's Supernova Remnant. (NASA/CXC/Rutgers/K.Eriksen et al.)

The Chandra X-Ray Observatory took a brand new, deep look inside the Tycho Supernova Remnant, providing a nearly three-dimensional view of the iconic space object.

Comet Lovejoy by Barry Armstead
Comet Lovejoy. Image Credit: Barry Armstead

And just the past several days southern skywatchers have been treated to the beautiful sights of Comet Lovejoy — which was also seen from the International Space Station. Go take a look!

These are just a sampling of the great images we’ve seen in 2011. Here’s to more great views in 2012!

New Submillimetre Camera Sheds Light on the Dark Regions of the Universe

A composite image of the Whirlpool Galaxy (also known as M51). The green image is from the Hubble Space Telescope and shows the optical wavelength. The submillimetre light detected by SCUBA-2 is shown in red (850 microns) and blue (450 microns). The Whirlpool Galaxy lies at an estimated distance of 31 million light years from Earth in the constellation Canes Venatici Credit: JAC / UBC / Nasa

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The stars and faint galaxies you see when you look up at the night sky are all emitting light within the visible light spectrum — the portion of the electromagnetic spectrum we can see with our unaided eyes or through optical telescopes. But our galaxy, and many others, contain huge amounts of cold dust that absorbs visible light. This accounts for the dark regions.

A new camera recently unveiled at the James Clerk Maxwell Telescope (JCMT) in Hawaii promises to figuratively shed light on this dark part of the universe. The SCUBA-2 submillimetre camera (SCUBA in this case is an acronym for Submillimetre Common-User Bolometer Array) can detect light at lower energy levels, allowing astronomers to gather data on these dark areas and ultimately learn more about our universe and its formation. 

Light is measurable; its intensity or brightness is measured by photons while colour is measured by the energy of the photons. Red photons have the least energy and violet photons have the most energy. This can also be thought of in terms of wavelengths. Light at longer wavelengths have less energy and light at shorter wavelengths have more energy. This continues beyond the visible light spectrum. As electromagnetic waves get shorter, we get ultraviolet light, x-rays, and gamma rays. As wavelengths get longer, we get infrared light, submillimetre light, and finally radio waves.

Panoramic view of the entire near-infrared sky reveals the distribution of galaxies beyond the Milky Way. Image credit: Thomas Jarrett, IPAC/Caltech.

On the longer end of the electromagnetic spectrum, infrared and radio telescopes have been around for decades helping astronomers understand more about the universe. But this is only part of the picture. The cold dust that absorbs the visible light to create the dark regions seen through optical telescopes is actually absorbing the light’s energy and reemitting it at longer wavelengths in the submillimetre region.

The first submillimetre camera, SCUBA, was designed and constructed at the Royal Observatory in Edinburgh in collaboration with the University of London. In 1997, it was up and running at the JCMT. Observations of submillimetre wavelengths are typically harder to gather — it takes a long time to image a small portion of the sky in this region. Nevertheless, submillimetre observations have already revealed a previously unknown population of distant, dusty galaxies as well as images of cold debris discs around nearby stars. This latter finding could be an indication of the presence of planetary systems.

A team of astronomers has recently developed the camera SCUBA-2 that can probe the submillimetre region with increased speed and much greater detail. But it’s a touchy instrument. Director of the JCMT Professor Gary Davis explains that for SCUBA-2 to detect extremely low energy radiation in the submillimetre region, “the instrument itself needs to be [extremely cold]. The detectors… have to be cooled to only 0.1 degree above absolute zero [–273.05°C], making the interior of SCUBA-2 colder than anything in the Universe that we know of!”

The infant Universe as imaged in the radio wavelength spectrum. Image Credit: NASA/WMAP Science Team.

The camera is a huge step in observational astronomy. Director of the United Kingdom Astronomy Teaching Centre Professor Ian Robson likened the technological leap between early sub-millimetre cameras and SCUBA-2 to the difference between wind-on film cameras and modern digital technology. “It is thanks to the ingenuity and abilities of our scientists and engineers that this immense leap in progress has been achieved,” he said.

Dr Antonio Chrysostomou, Associate Director of the JCMT, explains that SCUBA-2’s first task will be to carry out a series of surveys throughout the sky, mapping sites of star formation within our Galaxy, as well as planet formation around nearby stars. It will also survey our galactic neighbours and look into deep space to sample the youngest galaxies in the Universe. This latter task will be critical in helping astronomers understand how galaxies have evolved since the Big Bang.

The SCUBA-2 camera is housed on the 15 metre (about 50 foot) diameter JCMT situated close to the summit of Mauna Kea, Hawaii, at an altitude of 4092 metres (about 13,425 feet). It is typically used to study our Solar System, interstellar dust and gas, and distant galaxies.

Source: Revolutionary New Camera Reveals Dark Side of the Universe

 

The James Clerk Maxwell Telescope. Image credit: www.jach.hawaii.edu

 

 

The Holidays Are Coming! A Beginner’s Guide to Telescopes

The holidays are fast approaching, and you may be looking for gift ideas for your friends, loved ones and even yourself. Are you considering buying a telescope this year?

There are many different types of astronomical telescope available on the market and for the beginner, selecting one can be a bewildering experience. Before buying a telescope it is important to ask yourself: What objects do you want to see through your new telescope and how much can the person buying it afford to pay?

Not all telescopes are the same nor do they give the same results. Many amateur astronomers have two or more different telescopes for different types of observing, but there are some which offer a good compromise and most objects can be seen through them.

Once you have decided on the telescope’s main purpose and what you want to see through it, choosing one can become much easier. With the exception of the Moon, planets and close star clusters, interesting night sky objects are faint; in fact most will appear as just points of light. As a new observer you may be mainly interested in viewing the Moon and planets, and if this is the case, a telescope with a small objective (primary mirror or lens) may be sufficient.

Most observers quickly graduate to galaxies, nebulae, globular clusters, open clusters etc. To view these objects you will require a telescope with the largest aperture that is possible for your circumstances, which includes things like cost, weight, portability, etc.

Below are the 3 main types of telescope worth considering as a beginner:

Newtonian reflector telescopes are a popular choice for astronomical use because they have the lowest cost per inch of aperture. Observations of faint deep sky objects, such as Galaxies and Nebulae, can be achieved at a relatively reasonable cost by reflectors with mirror diameters of 150 to 200mm (6 to 8 inches).

Celestron Astromaster 130

Refractor telescopes are good for achieving high power and contrast when viewing the planets and the moon. They have a reputation of providing crisp, sharp-quality images. Since they are virtually maintenance free, they are easy to operate, but due to high costs for the large aperture scopes, most beginners will choose a Newtonian reflector as a first scope for all round astronomy. Short-tube refractors are now another low cost option for beginners. Their smaller size makes them an excellent choice for a portable telescope and the beautiful wide-field star vistas which they provide are great for learning your way around the night sky.
Bresser Refractor Telescope

Dobsonian Telescopes are one of the best choices for a general telescope and have many advantages including simplicity, economy and large light gathering ability. Dobsonians are actually large Newtonian telescopes on a simple manual Alt/ Az (Up, down, side to side) mount. Due to the mount and optical tube assembly being so simple, Dobsonian telescopes are the most economical on a cost per inch basis. This enables massive apertures being made affordable, bringing fainter objects within the grasp of the amateur and usually well within budget with mirror diameters from 150mm to 400mm (6 to 16 inches) or much larger.
Dobsonian Telescope
The Meade 16" LightBridge

Another consideration when choosing a telescope is the mount – the part the optical tube assembly sits on. Usually a tripod with a head containing manual or motorised controls, which point the telescope and track an object observed.

The three main types are:

Equatorial – Usually found paired with all telescopes apart from Dobsonians. Equatorial mounts enable the telescope to follow the rotation of the sky with on axis parallel to the Earth’s axis of rotation. They can also be used in a basic manual mode which can be manually moved by hand in the Altitude (up/down) and Azimuth (left/right) axis. Many higher end mounts have computers and GoTo systems incorporated which are almost essential for astrophotography.

Hand operated Manual Alt/ Az (Altitude/ Azimuth) – Usually found on very cheap or small telescopes, Dobsonian telescopes, binocular mounts and photographic tripods. Simple and easy to use, however they do not track objects across the sky.

GoTo or Computerised – Found on many mid to high range telescopes of all sizes and extremely popular with astrophotographers and imagers. Unfortunately many beginners are drawn to the sexy marketing of scopes that are computerised and this can be an expensive mistake. Personally I believe it to be better to use manually guided telescopes when starting out instead of jumping in straight away with computerised ones. It is much better to concentrate on good optics and a solid mount rather than waste lots of money on often complicated and unnecessary electronics. For more info on mounts and GoTo Systems see the Beginners Guide to GoTo

Hopefully this guide has given you more insight into the complicated world of telescopes, and enable you to make a better decision when buying your new telescope. Your new purchase should be one that you can enjoy and get the most out of for many years.

Looking For the City Lights of Alien Civilizations

Artist's conception of city lights on an alien planet. Credit: David A. Aguilar (CfA)

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When most people think about the search for alien life, the first thing that usually pops into mind is SETI (Search for Extraterrestrial Intelligence). Primarily a search for extraterrestrial radio signals, another more recent facet of SETI is now looking for laser pulses as a conceivable means of communication across interstellar distances. But now, a third option has been presented: looking for sources of artificial light on the surfaces of exoplanets, like the lights of cities on Earth.

According to Avi Loeb at the Harvard-Smithsonian Center for Astrophysics, “Looking for alien cities would be a long shot, but wouldn’t require extra resources. And if we succeed, it would change our perception of our place in the universe.”

Like the other SETI initiatives, it relies on an assumption that an alien civilization would use technologies that are similar to ours or at least recognizable. That assumption itself has been the subject of contentious debate over the years. If an alien society was thousands or millions of years more advanced than us, would any of its technology even be recognizable to us?

That aside, how easy (or not) would it be to spot the signs of artificial lighting on an alien planet light-years away from us? The suggestion is to look at the changes in light from an exoplanet as it orbits its star. Artificial light would increase in brightness on the dark side of a planet as it orbits the star (as the planet goes through its phases, like our Moon or other planets in our own solar system), becoming more visible than any light that is reflected from the day side.

That type of discovery will require the next generation of telescopes, but today’s telescopes could test the idea, being able to find something similar as far out as the Kuiper Belt in our solar system, where Pluto and thousands of other small icy bodies reside. As noted by Edwin Turner at Princeton University, “It’s very unlikely that there are alien cities on the edge of our solar system, but the principle of science is to find a method to check. Before Galileo, it was conventional wisdom that heavier objects fall faster than light objects, but he tested the belief and found they actually fall at the same rate.”

The paper has been submitted to the journal Astrobiology and is available here.

Latest Images of Comet Elenin: Not Much to See

Screenshot of a video of images from the GRAS telescopes in Mayhill Station, New Mexico on Oct. 21, 2011, showing what might be a diffuse blob of material, all that's left of Comet Elenin. Credit: Ernesto Guido, Giovanni Sostero and Nick Howes.

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A series of images of Comet Elenin taken on October 21, 2011 might show an “extremely faint and diffuse blob of light,” according to Ernesto Guido, Giovanni Sostero and Nick Howes, who used two remote telescopes in New Mexico to image again the field of view where Comet Elenin should be. Their first observing session with a 10” reflector showed no obvious moving object in the telescope’s field of view, while the second session a 0.1 meter refractor showed a hint of something moving in the background when images taken 2 hours apart were “blinked,” but interference from moonlight hasn’t been ruled out.

The trio of astronomers encourage other observers to confirm or refute this view with additional observations/images. “We suggest the use of wide-field, fast focal ratio scopes, possibly under very good sky conditions,” they said.

You can see more at the Remanzacco Observatory website, including a video of the “blinking.”

ALMA Opens Her Eyes — With Stunning Results

ALMA's first light: a view of the Antennae Galaxies. Credit: ESO

There’s a new telescope in town that just opened up for business. It’s the long awaited ALMA, the Atacama Large Millimeter/submillimeter Array. Although it is still under construction, the science teams have released the first “early science” image, showing a pair of interacting galaxies called the Antenna Galaxies. ALMA’s view reveals a part of the Universe that just can’t be seen by visible-light and infrared telescopes. “From the formation of the first galaxies, stars, and planets to the merging of the first complex molecules, the science of ALMA is a vast spectrum of investigation,” said Tania Burchell, the ALMA Public Information Officer at the National Radio Astronomy Observatory, on today’s 365 Days of Astronomy podcast.

A composite image combining images of the Antenna Galaxies from ALMA and the Hubble Space Telescope. Credit: ESO, Space Science Institute

Currently, about one third of ALMA’s eventual 66 radio antennas are built and operational. The antennas are positioned just 125 meters apart on the Chajnantor plateau in northern Chile. This extremely dry and high desert sits over 5,000 meters (16,500) feet above sea level. This puts ALMA higher than any other telescope array on Earth. At this elevation, the temperatures hover around freezing all year round, and the air pressure is half that at sea level. Cold temperatures combined with little air is perfect for telescopes like ALMA.

“Even in this very early phase ALMA already outperforms all other submillimetre arrays,” said Tim de Zeeuw, Director General of ESO, the European partner in ALMA. “Reaching this milestone is a tribute to the impressive efforts of the many scientists and engineers in the ALMA partner regions around the world who made it possible.”

Historically, collecting, focusing, and imaging millimeter and submillimeter waves has been very tricky, Burchell said.

“These waves are so large that mirrors cannot focus them, and their frequencies are too high for off-the-shelf receiver technologies to process,” said said. “The warmth of a telescope’s own electronics is enough to ruin the weak cosmic mm signals that, by the time they reach us, sputter in at about a billionth of a billionth the power of a cell phone call. And as an added torment, humidity itself broadcasts at these frequencies, turning most skies into a glare of millemeter/submillimeter light.”

But ALMA is radically different from visible-light and infrared telescopes. It is an array of linked antennas acting as a single giant telescope, and it detects much longer wavelengths than those of visible light. Its images therefore look quite unlike more familiar pictures of the cosmos.

Compare images of the Antenna Galaxies, from ALMA and the Very Large Telescope:

A comparison of the views of the Antenna Galaxies, from ALMA and the VLT. Credit: ESO.

ALMA’s view reveals the clouds of dense cold gas from which new stars form. This is the best submillimeter-wavelength image ever made of the Antennae Galaxies.

Massive concentrations of gas are found not only in the hearts of the two galaxies but also in the chaotic region where they are colliding. Here, the total amount of gas is billions of times the mass of our Sun — a rich reservoir of material for future generations of stars. Observations like these open a new window on the submillimetre Universe and will be vital in helping us understand how galaxy collisions can trigger the birth of new stars. This is just one example of how ALMA reveals parts of the Universe that cannot be seen with visible-light and infrared telescopes.

Learn more about AlMA in this video:

ALMA Opens Its Eyes

Sources: ESO, 365 Days of Astronomy, NRAO