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  • richardmitnick 2:26 pm on October 11, 2018 Permalink | Reply
    Tags: , , , , Caltech Palomar Observatory, , , iPTF=intermediate Palomar Transient Factory, Massive star’s unusual death heralds the birth of compact neutron star binary,   

    From Carnegie Institution for Science: “Massive star’s unusual death heralds the birth of compact neutron star binary” 

    Carnegie Institution for Science
    From Carnegie Institution for Science

    October 11, 2018

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    Carnegie’s Anthony Piro was part of a Caltech-led team of astronomers who observed the peculiar death of a massive star that exploded in a surprisingly faint and rapidly fading supernova, possibly creating a compact neutron star binary system. Piro’s theoretical work provided crucial context for the discovery. Their findings are published by Science.

    Observations made by the Caltech team—including lead author Kishalay De and project principal investigator Mansi Kasliwal (herself a former-Carnegie postdoc)—suggest that the dying star had an unseen companion, which gravitationally siphoned away most of the star’s mass before it exploded as a supernova. The explosion is believed to have resulted in a neutron star binary, suggesting that, for the first time, scientists have witnessed the birth of a binary system like the one first observed to collide by Piro and a team of Carnegie and UC Santa Cruz astronomers in August 2017.

    A supernova occurs when a massive star—at least eight times the mass of the Sun—exhausts its nuclear fuel, causing the core to collapse and then rebound outward in a powerful explosion. After the star’s outer layers have been blasted away, all that remains is a dense neutron star—an exotic star about the size of a city but containing more mass than the Sun.

    Usually, a lot of material—many times the mass of the Sun—is observed to be blasted away in a supernova. However, the event that Kasliwal and her colleagues observed, dubbed iPTF 14gqr, ejected matter only one fifth of the Sun’s mass.

    “We saw this massive star’s core collapse, but we saw remarkably little mass ejected,” Kasliwal says. “We call this an ultra-stripped envelope supernova and it has long been predicted that they exist. This is the first time we have convincingly seen core collapse of a massive star that is so devoid of matter.”

    Piro’s theoretical modeling guided the interpretation of these observations. This allowed the observers to infer the presence of dense material surrounding the explosion.

    “Discoveries like this demonstrate why it has been so important to build a theoretical astrophysics group at Carnegie,” Piro said. “By combining observations and theory together, we can learn so much more about these amazing events.”

    The fact that the star exploded at all implies that it must have previously had a lot of material, or its core would never have grown large enough to collapse. But where was the missing mass hiding? The researchers inferred that the mass must have been stolen by a compact companion star, such as a white dwarf, neutron star, or black hole.

    The neutron star that was left behind from the supernova must have then been born into orbit with this compact companion. Because this new neutron star and its companion are so close together, they will eventually merge in a collision. In fact, the merger of two neutron stars was first observed in August 2017 by Piro and a team of Carnegie and UC Santa Cruz astronomers, and such events are thought to produce the heavy elements in our universe, such as gold, platinum, and uranium.

    The event was first seen at Palomar Observatory as part of the intermediate Palomar Transient Factory (iPTF), a nightly survey of the sky to look for transient, or short-lived, cosmic events like supernovae.

    Caltech Palomar Observatory, located in San Diego County, California, US, at 1,712 m (5,617 ft)

    Caltech Palomar Intermediate Palomar Transient Factory telescope at the Samuel Oschin Telescope at Palomar Observatory,located in San Diego County, California, United States

    Because the iPTF survey keeps such a close eye on the sky, iPTF 14gqr was observed in the very first hours after it had exploded. As the earth rotated and the Palomar telescope moved out of range, astronomers around the world collaborated to monitor iPTF 14gqr, continuously observing its evolution with a number of telescopes that today form the Global Relay of Observatories Watching Transients Happen (GROWTH) network of observatories.

    GROWTH map

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    The three panels represent moments before, when and after the faint supernova iPTF14gqr, visible in the middle panel, appeared in the outskirts of a spiral galaxy located 920 million light years away from us. The massive star that died in the supernova left behind a neutron star in a very tight binary system. These dense stellar remnants will ultimately spiral into each other and merge in a spectacular explosion, giving off gravitational and electromagnetic waves. Image credit: SDSS/Caltech/Keck

    SDSS Telescope at Apache Point Observatory, near Sunspot NM, USA, Altitude 2,788 meters (9,147 ft)


    Keck Observatory, Maunakea, Hawaii, USA.4,207 m (13,802 ft), above sea level, showing also NASA’s IRTF and NAOJ Subaru

    See the full article here .


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    Carnegie Institution of Washington Bldg

    Andrew Carnegie established a unique organization dedicated to scientific discovery “to encourage, in the broadest and most liberal manner, investigation, research, and discovery and the application of knowledge to the improvement of mankind…” The philosophy was and is to devote the institution’s resources to “exceptional” individuals so that they can explore the most intriguing scientific questions in an atmosphere of complete freedom. Carnegie and his trustees realized that flexibility and freedom were essential to the institution’s success and that tradition is the foundation of the institution today as it supports research in the Earth, space, and life sciences.

    6.5 meter Magellan Telescopes located at Carnegie’s Las Campanas Observatory, Chile.
    6.5 meter Magellan Telescopes located at Carnegie’s Las Campanas Observatory, Chile

     
  • richardmitnick 9:00 am on June 5, 2017 Permalink | Reply
    Tags: , , , Caltech Palomar Observatory, , G292.0+1.8, ,   

    From Chandra via Manu Garcia: “G292.0+1.8: Stellar Forensics with Striking Image from Chandra” 

    NASA Chandra Telescope

    NASA Chandra

    Via Manu Garcia

    Manu Garcia, a friend from IAC.

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    Credit: X-ray: NASA/CXC/Penn State/S.Park et al.; Optical: Pal.Obs. DSS

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    Calteh Palomar Observatory in San Diego County, California, United States

    The aftermath of the death of a massive star is shown in beautiful detail in this new composite image of G292.0+1.8. In color is the Chandra X-ray Observatory image – easily the deepest X-ray image ever obtained of this supernova remnant – and in white is optical data from the Digitized Sky Survey. Although considered a “textbook” case of a supernova remnant, the intricate structure shown here reveals a few surprises.

    Near the center of G292.0+1.8 is the so-called pulsar wind nebula, most easily seen in high energy X-rays. This is the magnetized bubble of high-energy particles that surrounds the “pulsar”, a rapidly rotating neutron star that remained behind after the original, massive star exploded. The narrow, jet-like feature running from north to south in the image is likely parallel to the spin axis of the pulsar.

    The pulsar is located slightly below and to the left of the center of G292.0+1.8. Assuming that the pulsar was born at the center of the remnant, it is thought that recoil from the lopsided explosion may have kicked the pulsar in this direction. However, the kick direction and the pulsar spin direction do not appear to be aligned, in contrast to apparent spin-kick alignments seen in some other supernova remnants.

    Another key feature of this remnant is the long white line running from left to right across the center called the equatorial belt. This structure is thought to be created when the star – before it died – expelled material from around its equator via winds. The orientation of the equatorial belt suggests the parent star maintained the same spin axis both before and after it exploded.

    One puzzling aspect of the image is the lack of evidence for thin filaments of high energy X-ray emission, thought to be an important site for cosmic ray acceleration in supernova remnants. These filaments are seen in other supernova remnants such as Cassiopeia A, Tycho and Kepler. One explanation may be that efficient acceleration occurs primarily in very early stages of supernova remnant evolution, and G292.0+1.8, with an estimated age of several thousand years, is too old to show these effects. Casseiopeia A, Tycho and Kepler, with ages of several hundred years, are much younger.

    See the full article here .

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    NASA’s Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for NASA’s Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra’s science and flight operations from Cambridge, Mass.

     
  • richardmitnick 11:18 am on December 15, 2016 Permalink | Reply
    Tags: , Caltech Palomar Observatory, , Supernovas & Supernova Remnants, W49B: Smoking Gun Found for Gamma-Ray Burst in Milky Way   

    From Chandra- “W49B: Smoking Gun Found for Gamma-Ray Burst in Milky Way” 

    NASA Chandra Banner
    NASA Chandra Telescope

    NASA Chandra

    June 02, 2004 {From earlier than this blog.]

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    Credit X-ray: NASA/CXC/SSC/J. Keohane et al.; Infrared: Caltech/SSC/J.Rho and T. Jarrett
    Category Supernovas & Supernova Remnants
    Constellation Aquila
    Observation Dates July 08, 2000
    Distance Estimate 26,000 light years

    A composite Chandra X-ray (blue) and Palomar infrared (red and green) image of the supernova remnant W49B reveals a barrel-shaped nebula consisting of bright infrared rings around a glowing bar of intense X-radiation along the axis.

    Caltech Palomar 200 inch Hale Telescope, at Mt Wilson, CA, USA
    Caltech Palomar 200 inch Hale Telescope interior
    Caltech Palomar 200 inch Hale Telescope, at Mt Wilson, CA, USA

    The X-rays in the bar are produced by 15 million degree Celsius gas that is rich in iron and nickel ions. At the ends of the barrel, the X-ray emission flares out to make a hot cap. The X-ray cap is surrounded by a flattened cloud of hydrogen molecules detected in the infrared. These features indicate that jets of hot gas produced in the supernova have encountered a large, dense cloud of gas and dust.

    The following sequence of events has been suggested to account for the X-ray and infrared data: A massive star formed from a dense cloud of dust and gas, shone brightly for a few million years while spinning off rings of gas and pushing them away to form a nearly empty cavity around the star. The star then exhausted its nuclear fuel and its core collapsed to form a black hole. Much of the gas around the black hole was pulled into it, but some, including material rich in iron and nickel was flung away in oppositely directed jets of gas traveling near the speed of light. When the jet hit the dense cloud surrounding the star, it flared out and drove a shock wave into the cloud.

    An observer aligned with one these jets would have seen a gamma-ray burst, a blinding flash in which the concentrated power equals that of ten quadrillion Suns for a minute or so. The view perpendicular to the jets would be a less astonishing, although nonetheless spectacular supernova explosion. For W49B, the jet is tilted out of the plane of the sky by about 20 degrees, but the remains of the jet are visible as a hot X-ray emitting bar of gas.

    W49B is about 35 thousand light years away, whereas the nearest known gamma-ray burst to Earth is several million light years away – most are billions of light years distant. If confirmed, the discovery of a relatively nearby remnant of a gamma-ray burst would give scientists an excellent opportunity to study the aftermath of one of nature’s most violent explosions.

    See the full article here .

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    NASA’s Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for NASA’s Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra’s science and flight operations from Cambridge, Mass.

     
  • richardmitnick 7:41 pm on May 19, 2015 Permalink | Reply
    Tags: , , Caltech Palomar Observatory,   

    From NPR: “‘Playing Around With Telescopes’ To Explore Secrets Of The Universe” 

    NPR

    National Public Radio (NPR)

    May 16, 2015
    Joe Palca

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    The 200-inch Hale Telescope, a masterpiece of engineering at Caltech’s Palomar Observatory, was the world’s largest telescope until 1993. Scott Kardel/Palomar Observatory/Courtesy of Palomar Observatory/California Institute of Technology

    Shrinivas Kulkarni, an astronomy and planetary science professor at the California Institute of Technology, is a serious astronomer. But not too serious.

    “We astronomers are supposed to say, ‘We wonder about the stars and we really want to think about it,’ ” says Kulkarni — in other words, think deep thoughts. But he says that’s not really the way it is.

    “Many scientists, I think, secretly are what I call ‘boys with toys,’ ” he says. “I really like playing around with telescopes. It’s just not fashionable to admit it.”

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    Shrinivas Kulkarni is one of the world’s foremost astronomers, but he also raises rabbits, is fascinated by the history of economic collapse — and dreams of being a bartender. Bob Paz/Courtesy of California Institute of Technology

    Make no mistake, Kulkarni says by “playing” with toys like optical telescopes, radio telescopes and space telescopes, astronomers have made measurements that reveal the age of the universe, the fact that it’s expanding and that there are lots of other solar system besides ours out there.

    Many of those fundamental discoveries — including measuring the rate at which the universe is expanding and determining the composition of stars — were made using telescopes at the Palomar Observatory, which Kulkarni now directs. He invited me to visit so I could get a sense of the wonder astronomers feel when working at the observatory.

    On a Wednesday morning earlier this year, I picked Kulkarni up from his home near Caltech’s Pasadena campus. The drive from Pasadena to Palomar in the mountains north of San Diego takes about 2 1/2 hours.

    Kulkarni was born in India in 1956. He has been an astronomer his entire professional life. But look at the whole person and you’ll see a man of contrasts. He loves Brazilian music. He raises bunny rabbits. And he says one of his deepest passions is the exact opposite of astronomy: It’s the history of great economic collapses.

    “Something like astronomy is terribly important because it’s about the universe,” he says. “We are learning something totally fundamental — how where we live comes about. But it’s not something immediate. It really doesn’t matter if the Big Bang happened 13.7 billion years ago or 13.75 billion years ago. On the other hand, economics, it sure is actually unimportant in the long run, but it surely matters today.”

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    The dome at Caltech’s Palomar Observatory, shown in a long-exposure nighttime shot, houses the 200-inch Hale Telescope.
    Courtesy of Palomar Observatory/California Institute of Technology

    As we approach the observatory, the road starts climbing through a forest on the side of a mountain. A little farther ahead, a large dome appears, stark white against the blue sky.

    “Now you can see the 200-inch or sometimes called the ‘Big Eye,’ ” says Kulkarni.

    For nearly 50 years, the 200-inch Hale Telescope at Palomar was the largest in the world. It’s a masterpiece of engineering. Even though it’s aging, Kulkarni says it can still be used for good science. Besides, he loves it here.

    When the dome slides open, the view of the sky is breathtaking.

    To stand here with Kulkarni is to bring together the past and the future. For as much as Kulkarni delights in this place, as inspiring as it is to be here, he says actually visiting a telescope is soon to be a thing of the past.

    “The best way to do astronomy is to get the astronomers out of the dome,” he says. “And the human in the loop becomes monotonous. If a machine can do it, honestly, I think everyone is happy.”

    Machines are good for studying the sky because they have no preconceived notions about what they’ll find. Astronomers, Kulkarni says, just don’t have the imagination to know what to look for.

    “The sky is so much richer and so much more imaginative than the imagination that you should always approach it with a certain sense of openness,” he says.

    Kulkarni says you look at the information the machines collect and try to figure out what it’s telling you. That’s the way you make discoveries.

    Kulkarni is 58. I asked him if he thought he’d ever get tired of playing with his toys. He said not really — but he knows someday he’ll have to try something different.

    “My wife’s been on me about what I’ll do after I retire. She said, ‘You’re always running around and doing things.’ And I want to be a bartender.”

    A bartender?

    Well, a man can dream.

    See the full article here.

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  • richardmitnick 9:51 am on March 28, 2015 Permalink | Reply
    Tags: , , Caltech Palomar Observatory,   

    From JPL: “Planet ‘Reared’ by Four Parent Stars” 

    JPL

    March 4, 2015
    Whitney Clavin
    Jet Propulsion Laboratory, Pasadena, California
    818-354-4673
    whitney.clavin@jpl.nasa.gov

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    This artist’s conception shows the 30 Ari system, which includes four stars and a planet. The planet, a gas giant, orbits its primary star (yellow) in about a year’s time. The primary star, called 30 Ari B, has a companion — the small “red dwarf” star shown at upper left. This pair of stars is itself locked in a long-distance orbit with another pair of stars (upper right), known as 30 Ari A. Researchers using instruments at the Palomar Observatory near San Diego, Calif., recently discovered the red star at upper left, bringing the total number of known stars in the system from three to four. Image copyright: Karen Teramura, UH IfA

    — Astronomers have discovered the second known case of a planet residing in a quadruple star system.

    — The planet was known before, but was thought to have only three stars, not four.

    — The findings help researchers understand how multiple star systems can influence the development and fate of planets.

    Growing up as a planet with more than one parent star has its challenges. Though the planets in our solar system circle just one star — our sun — other more distant planets, called exoplanets, can be reared in families with two or more stars. Researchers wanting to know more about the complex influences of multiple stars on planets have come up with two new case studies: a planet found to have three parents, and another with four.

    The discoveries were made using instruments fitted to telescopes at the Palomar Observatory in San Diego: the Robo-AO adaptive optics system, developed by the Inter-University Center for Astronomy and Astrophysics in India and the California Institute of Technology in Pasadena, and the PALM-3000 adaptive optics system, developed by NASA’s Jet Propulsion Laboratory in Pasadena, California, and Caltech.

    Caltech Palomar Robo-AO on P60 telescope
    Robo-AO
    Caltech Palomar 1.5m 60in telescope
    Caltech Palomar 1.5 m 60in telescope interior
    Caltech Palomar P60 telescope which houses the Robo-AO system

    Caltech Palomar 200 inch Hale Telescope PALM 3000 AO System
    PALM 3000 AO System
    Caltech Palomar 200 inch Hale Telescope
    Caltech Palomar 200 inch Hale Telescope interior
    Caltech Palomar 200 inch Hale Telescope which houses the PALM-3000 adaptive optics system

    This is only the second time a planet has been identified in a quadruple star system. While the planet was known before, it was thought to have only three stars, not four. The first four-star planet, KIC 4862625, was discovered in 2013 by citizen scientists using public data from NASA’s Kepler mission.

    NASA Kepler Telescope
    NASA/Kepler

    The latest discovery suggests that planets in quadruple star systems might be less rare than once thought. In fact, recent research has shown that this type of star system, which usually consists of two pairs of twin stars slowly circling each other at great distances, is itself more common than previously believed.

    “About four percent of solar-type stars are in quadruple systems, which is up from previous estimates because observational techniques are steadily improving,” said co-author Andrei Tokovinin of the Cerro Tololo Inter-American Observatory in Chile.

    The newfound four-star planetary system, called 30 Ari, is located 136 light-years away in the constellation Aries. The system’s gaseous planet is enormous, with 10 times the mass of Jupiter, and it orbits its primary star every 335 days. The primary star has a relatively close partner star, which the planet does not orbit. This pair, in turn, is locked in a long-distance orbit with another pair of stars about 1,670 astronomical units away (an astronomical unit is the distance between Earth and the sun). Astronomers think it’s highly unlikely that this planet, or any moons that might circle it, could sustain life.

    Were it possible to see the skies from this world, the four parent stars would look like one small sun and two very bright stars that would be visible in daylight. One of those stars, if viewed with a large enough telescope, would be revealed to be a binary system, or two stars orbiting each other.

    In recent years, dozens of planets with two or three parent stars have been found, including those with “Tatooine” sunsets reminiscent of the Star Wars movies. Finding planets with multiple parents isn’t too much of a surprise, considering that binary stars are more common in our galaxy than single stars.

    “Star systems come in myriad forms. There can be single stars, binary stars, triple stars, even quintuple star systems,” said Lewis Roberts of JPL, lead author of the new findings appearing in the journal Astronomical Journal. “It’s amazing the way nature puts these things together.”

    Roberts and his colleagues want to understand the effects that multiple parent stars can have on their developing youthful planets. Evidence suggests that stellar companions can influence the fate of planets by changing the planets’ orbits and even triggering some to grow more massive. For example, the “hot Jupiters” — planets around the mass of Jupiter that whip closely around their stars in just days — might be gently nudged closer to their primary parent star by the gravitational hand of a stellar companion.

    In the new study, the researchers describe using the automated Robo-AO system on Palomar Observatory to scan the night skies, searching hundreds of stars each night for signs of stellar companions. They found two candidates hosting exoplanets: the four-star system 30 Ari, and a triple-star planetary system called HD 2638. The findings were confirmed using the higher-resolution PALM-3000 instrument, also at Palomar Observatory.

    The new planet with a trio of stars is a hot Jupiter that circles its primary star tightly, completing one lap every three days. Scientists already knew this primary star was locked in a gravitational tango with another star, about 0.7 light-years away, or 44,000 astronomical units. That’s relatively far apart for a pair of stellar companions. The latest discovery is of a third star in the system, which orbits the primary star from a distance of 28 astronomical units — close enough to have influenced the hot Jupiter’s development and final orbit.

    “This result strengthens the connection between multiple star systems and massive planets,” said Roberts.

    In the case of Ari 30, the discovery brought the number of known stars in the system from three to four. The fourth star lies at a distance of 23 astronomical units from the planet. While this stellar companion and its planet are closer to each other than those in the HD 2638 system, the newfound star does not appear to have impacted the orbit of the planet. The exact reason for this is uncertain, so the team is planning further observations to better understand the orbit of the star and its complicated family dynamics.

    See the full article here.

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    NASA JPL Campus

    Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. Although the facility has a Pasadena postal address, it is actually headquartered in the city of La Cañada Flintridge, on the northwest border of Pasadena. JPL is managed by the nearby California Institute of Technology (Caltech) for the National Aeronautics and Space Administration. The Laboratory’s primary function is the construction and operation of robotic planetary spacecraft, though it also conducts Earth-orbit and astronomy missions. It is also responsible for operating NASA’s Deep Space Network.

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  • richardmitnick 9:49 am on November 28, 2014 Permalink | Reply
    Tags: , , , Caltech Palomar Observatory, ,   

    From SPACE.com: “Mars and Two Nebulas Shine in Stunning Skywatcher Photos” 

    space-dot-com logo

    SPACE.com

    November 28, 2014
    Nina Sen

    These amazing images show the planet Mars passing below two nebulas.

    Astrophotographer Derek Demeter took the images from the Stardust Ranch in Okeechobee, Florida. Demeter is the director of the Emil Buehler Perpetual Trust Planetarium at Seminole State College of Florida.

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    These amazing images are of the planet Mars passing below two nebulas. Astrophotographer Derek Demeter took the images from the Stardust Ranch in Okeechobee,
    Credit: Derek Demeter/Seminole State College

    The photos capture Mars passing below two objects known as the Lagoon and Trifid nebulas. Both are located in the constellation Sagittarius and are found in the central region of our Milky Way galaxy.

    ln
    The VLT Survey Telescope (VST) at ESO’s Paranal Observatory in Chile has captured this richly detailed new image of the Lagoon Nebula. This giant cloud of gas and dust is creating intensely bright young stars, and is home to young stellar clusters. This image is a tiny part of just one of eleven public surveys of the sky now in progress using ESO telescopes. Together these are providing a vast legacy of publicly available data for the global astronomical community.

    ESO VLT Survey telescope
    ESO/VLT Survey Telescope (VST)

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    The Trifid nebula (M20, NGC NGC 6514) in pseudocolor.
    Image taken with the Palomar 1.5-m telescope. The field of view is 16’ ´ 16’. Red shows [S II] ll 6717+6731. Green shows Ha l 6563. Blue shows [O III] l 5007. The WFPC2 field of view is indicated. CREDIT: Jeff Hester (Arizona State University), Palomar telescope.

    Caltech Palomar 1.5m 60in telescope
    Palomar 1.5-m telescope

    Located about 5,000 light-years from Earth, the Lagoon Nebula is one of two star-forming regions visible to the unaided eye from the Northern Hemisphere. It is about 110 light-years across and is also known as Messier 8 or NGC 6523. The Trifid Nebula (Messier 20 or NGC 6514) is a combination of an emission nebula (the red area), a reflection nebula (the blue area) and a dark nebula. Also visible are the star-forming regions of NGC 6559, IC 1274 and IC 1275.

    See the full article here.

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