Wednesday, July 19, 2017

Saturn Close-up | NASA Cassini Mission



Assembled using near-infrared, red, and green filtered images taken of Saturn by Cassini on July 16, 2017.

The Cassini mission is a cooperative project of NASA, ESA (the European Space Agency) and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colorado.

For more information about the Cassini-Huygens mission visit: http://saturn.jpl.nasa.gov and http://www.nasa.gov/cassini
The Cassini imaging team homepage is at http://ciclops.org

Credit: NASA/JPL-Caltech//Space Science Institute/Kevin M. Gill
Image Date: July 16, 2017
Release Date: July 17, 2017


#NASA #Astronomy #Science #Space #Saturn #Planet #Rings #Atmosphere #SolarSystem #Exploration #Cassini #Spacecraft #JPL #Pasadena #California #UnitedStates #ESA #ASI #STEM #Education

Monday, July 17, 2017

NASA Langley, Neil Armstrong and The Space Race


Image: Neil Armstrong in flight suit with lunar module simulator in 1969.
When the United States set a goal of landing a man on the moon, NASA Langley Research Center tackled the many challenges of spaceflight, trained astronauts, managed Project Mercury, and assumed major roles in both the Gemini and Apollo programs. Langley led the Lunar Orbiter initiative, which not only mapped the moon, but chose the spot for the first human landing. Langley aerospace engineer John Houbolt championed the lunar-orbit rendezvous concept, enabling the Apollo 11 moon landing and the safe return of its crew to Earth.

Neil Armstrong, the first human to set foot on the lunar surface, trained at Langley's Lunar Landing Research Facility on equipment that cancelled all but one-sixth of Earth's gravitational force to match that of the moon's. This photograph shows Armstrong at the Lunar Landing Research Facility on Feb. 12, 1969. Twenty-four astronauts practiced touchdowns at the facility, where overhead cables supported five-sixths of the weight of a full-size model lander, and thrust was provided by a working rocket engine.

Part of the landing facility was the Reduced Gravity Simulator, which was attached to an overhead, lightweight trolley track. There, suspended on one side by a network of slings and cables, an astronaut's ability to walk, run, and perform the various tasks required during lunar excursions was evaluated.

Armstrong offered what was perhaps the greatest tribute to the importance of his Langley training in Apollo 11's success. When asked what it was like to land on the moon, he replied: "Like Langley."

Image Credit: NASA/Langley Research Center
Image Date: Feb. 12, 1969
Release Date: July 17, 2017

#NASA #Space #Apollo #Moon #Lunar #Landing #Langley #Research #Astronaut #NeilArmstrong #Apollo11 #History #Centennial #Pioneers #Hampton #Virginia #UnitedStates #STEM #Education

Roll-Out Solar Array (ROSA) | International Space Station


U.S. Astronaut Jack Fischer: "One recent experiment (ROSA) looked at a new solar array that unfurled like a party horn on New Year’s and it worked!"

ROSA is an experiment to test a new type of solar array that rolls open in space like a party favor and is more compact than current rigid panel designs.

Learn more about this new U.S. technology at:
Deployable Space Systems, Inc. (DSS)
http://www.dss-space.com

Credit: NASA/JSC
Release Date: July 15, 2017


#NASA #ISS #Earth #Planet #Science #Space #Solar #SolarArray #ROSA #DSS #Testing #Experiment #Renewable #Energy #Engineering #EarthObservation #Astronaut #JackFischer #Expedition52 #Human #Spaceflight #Technology #CSA #Canadarm2 #Dextre #Photography #JSC #UnitedStates #OverviewEffect #OrbitalPerspective #STEM #Education

Friday, July 14, 2017

Jupiter's Great Red Spot (Enhanced Color) | NASA Juno Mission


July 13, 2017: This enhanced-color image of Jupiter's Great Red Spot was created by citizen scientists Gerald Eichstadt and Seán Doran using data from the JunoCam imager on NASA's Juno spacecraft.

This image is approximately illumination adjusted and strongly enhanced to draw viewers' eyes to the iconic storm and the turbulence around it.

The image was taken on July 10, 2017 as the Juno spacecraft performed its 7th close flyby of Jupiter.

More information about Juno is online at http://www.nasa.gov/juno and http://missionjuno.swri.edu.

Credit: NASA/JPL-Caltech/SwRI/MSSS/Gerald Eichstadt/Seán Doran
Release Date: July 13, 2017


#NASA #Astronomy #Space #Science #Jupiter #Planet #Atmosphere #GreatRedSpot #GRS #Juno #Spacecraft #SwRI #JPL #Pasadena #California #UnitedStates #STEM #Education #CitizenScience

Thursday, July 13, 2017

Dragon Scales of Mars | NASA's Mars Reconnaissance Orbiter


This intriguing surface texture is the result of rock interacting with water. The rock was then eroded and later exposed to the surface. The pinkish, almost dragon-like scaled texture represents Martian bedrock that has specifically altered into a clay-bearing rock.

The nature of the water responsible for the alteration, and how it interacted with the rock to form the clay remains poorly understood. Not surprisingly, the study of such altered rocks on Mars is an area of active investigation by the Mars science community. Understanding such interactions, and how they happened, help scientists to understand the past climate on Mars, and if the red planet ever harbored life.

Recent studies indicate that the early Martian climate may not have been as warm, wet, and Earth-like, as previously suggested. This is not a problem for finding life on Mars as one might think. Ongoing studies of dry and cold environments on Earth shows that life finds ways to adapt to such extremes. Such work provides hope for finding evidence for life on other planets, like Mars, someday.

Image Credit: NASA/JPL-Caltech/University of Arizona
Caption Credit: Livio L. Tornabene, Jon Kissi, Zach Morse and Gavin Tolometti Release Date: July 11, 2017

#NASA #Astronomy #Science #Space #Mars #Geology #Geoscience #Clay #Water #Bedrock #MRO #HiRISE #Spacecraft #JPL #Pasadena #California #UnitedStates #SolarSystem #STEM #Education

Jupiter's Great Red Spot | NASA Juno Mission


July 12, 2017: This color image of Jupiter's Great Red Spot was created by citizen scientist Gerald Eichstadt using data from the JunoCam imager on NASA's Juno spacecraft.

The image was taken on July 10, 2017 as the Juno spacecraft performed its 7th close flyby of Jupiter.

More information about Juno is online at http://www.nasa.gov/juno and http://missionjuno.swri.edu.

Credit: NASA/JPL-Caltech/SwRI/MSSS/Gerald Eichstadt
Release Date: July 12, 2017

#NASA #Astronomy #Space #Science #Jupiter #Planet #Atmosphere #GreatRedSpot #GRS #Juno #Spacecraft #SwRI #JPL #Pasadena #California #UnitedStates #STEM #Education #CitizenScience

Wednesday, July 12, 2017

NASA's Juno Spacecraft Spots Jupiter's Great Red Spot


This enhanced-color image of Jupiter's Great Red Spot was created by citizen scientist Gerald Eichstädt using data from the JunoCam imager on NASA's Juno spacecraft. | July 12, 2017: Images of Jupiter's Great Red Spot reveal a tangle of dark, veinous clouds weaving their way through a massive crimson oval. The JunoCam imager aboard NASA's Juno mission snapped pics of the most iconic feature of the solar system's largest planetary inhabitant during its Monday (July 10) flyby. The images of the Great Red Spot were downlinked from the spacecraft's memory on Tuesday and placed on the mission's JunoCam website Wednesday morning.

"For hundreds of years scientists have been observing, wondering and theorizing about Jupiter's Great Red Spot," said Scott Bolton, Juno principal investigator from the Southwest Research Institute in San Antonio. "Now we have the best pictures ever of this iconic storm. It will take us some time to analyze all the data from not only JunoCam, but Juno's eight science instruments, to shed some new light on the past, present and future of the Great Red Spot."

As planned by the Juno team, citizen scientists took the raw images of the flyby from the JunoCam site and processed them, providing a higher level of detail than available in their raw form. The citizen-scientist images, as well as the raw images they used for image processing, can be found at:

https://www.missionjuno.swri.edu/junocam/processing

"I have been following the Juno mission since it launched," said Jason Major, a JunoCam citizen scientist and a graphic designer from Warwick, Rhode Island. "It is always exciting to see these new raw images of Jupiter as they arrive. But it is even more thrilling to take the raw images and turn them into something that people can appreciate. That is what I live for."

Measuring in at 10,159 miles (16,350 kilometers) in width (as of April 3, 2017) Jupiter's Great Red Spot is 1.3 times as wide as Earth. The storm has been monitored since 1830 and has possibly existed for more than 350 years. In modern times, the Great Red Spot has appeared to be shrinking.

All of Juno's science instruments and the spacecraft's JunoCam were operating during the flyby, collecting data that are now being returned to Earth. Juno's next close flyby of Jupiter will occur on Sept. 1.

Juno reached perijove (the point at which an orbit comes closest to Jupiter's center) on July 10 at 6:55 p.m. PDT (9:55 p.m. EDT). At the time of perijove, Juno was about 2,200 miles (3,500 kilometers) above the planet's cloud tops. Eleven minutes and 33 seconds later, Juno had covered another 24,713 miles (39,771 kilometers), and was passing directly above the coiling, crimson cloud tops of the Great Red Spot. The spacecraft passed about 5,600 miles (9,000 kilometers) above the clouds of this iconic feature.

Juno launched on Aug. 5, 2011, from Cape Canaveral, Florida. During its mission of exploration, Juno soars low over the planet's cloud tops -- as close as about 2,100 miles (3,400 kilometers). During these flybys, Juno is probing beneath the obscuring cloud cover of Jupiter and studying its auroras to learn more about the planet's origins, structure, atmosphere and magnetosphere.

Early science results from NASA's Juno mission portray the largest planet in our solar system as a turbulent world, with an intriguingly complex interior structure, energetic polar aurora, and huge polar cyclones.

"These highly-anticipated images of Jupiter's Great Red Spot are the 'perfect storm' of art and science. With data from Voyager, Galileo, New Horizons, Hubble and now Juno, we have a better understanding of the composition and evolution of this iconic feature," said Jim Green, NASA's director of planetary science. "We are pleased to share the beauty and excitement of space science with everyone."

JPL manages the Juno mission for the principal investigator, Scott Bolton, of Southwest Research Institute in San Antonio. The Juno mission is part of the New Frontiers Program managed by NASA's Marshall Space Flight Center in Huntsville, Alabama, for the Science Mission Directorate. Lockheed Martin Space Systems, Denver, built the spacecraft. JPL is a division of Caltech in Pasadena.

More information on the Juno mission is available at:
https://www.nasa.gov/juno
http://missionjuno.org

More information on the Great Red Spot can be found at:
https://www.nasa.gov/feature/goddard/jupiter-s-great-red-spot-a-swirling-mystery
https://www.nasa.gov/feature/jupiter-s-great-red-spot-likely-a-massive-heat-source

More information on Jupiter can be found at:
https://www.nasa.gov/jupiter

Credit: NASA/JPL-Caltech/SwRI/MSSS/Gerald Eichstadt
Release Date: July 12, 2017


#NASA #Astronomy #Space #Science #Jupiter #Planet #Atmosphere #GreatRedSpot #GRS #Juno #Spacecraft #SwRI #JPL #Pasadena #California #UnitedStates #STEM #Education #CitizenScience

Jupiter's Great Red Spot | NASA Juno Mission


The Great Red Spot (GRS) in Jupiter's southern hemisphere has delighted and mystified since its discovery in the 17th Century. With its swirl of reddish hues, it is 2-3 times as wide as Earth and is seen by many as a “perpetual hurricane,” with winds peaking at about 400 miles an hour.

NASA's Jet Propulsion Laboratory manages the Juno mission for the principal investigator, Scott Bolton, of Southwest Research Institute in San Antonio. Juno is part of NASA's New Frontiers Program, which is managed at NASA's Marshall Space Flight Center in Huntsville, Alabama, for NASA's Science Mission Directorate. Lockheed Martin Space Systems, Denver, built the spacecraft. Caltech in Pasadena, California, manages JPL for NASA.

More information about Juno is online at http://www.nasa.gov/juno and http://missionjuno.swri.edu

Credit: NASA/JPL-Caltech/MSSS/SwRI
Processing: Gerald Eichstädt/Seán Doran
Release Date: July 12, 2017


#NASA #Astronomy #Space #Science #Jupiter #Planet #Atmosphere #GreatRedSpot #GRS #Juno #Spacecraft #SwRI #JPL #Pasadena #California #UnitedStates #STEM #Education

NASA's Chandra Peers into a Nurturing Cloud


Image: The giant molecular cloud known as W51 is one of the closest to Earth at a distance of about 17,000 light years.
July 12, 2017: In the context of space, the term ‘cloud’ can mean something rather different from the fluffy white collections of water in the sky or a way to store data or process information. Giant molecular clouds are vast cosmic objects, composed primarily of hydrogen molecules and helium atoms, where new stars and planets are born. These clouds can contain more mass than a million suns, and stretch across hundreds of light years.

The giant molecular cloud known as W51 is one of the closest to Earth at a distance of about 17,000 light years. Because of its relative proximity, W51 provides astronomers with an excellent opportunity to study how stars are forming in our Milky Way galaxy.

A new composite image of W51 shows the high-energy output from this stellar nursery, where X-rays from Chandra are colored blue. In about 20 hours of Chandra exposure time, over 600 young stars were detected as point-like X-ray sources, and diffuse X-ray emission from interstellar gas with a temperature of a million degrees or more was also observed. Infrared light observed with NASA’s Spitzer Space Telescope appears orange and yellow-green and shows cool gas and stars surrounded by disks of cool material.

W51 contains multiple clusters of young stars. The Chandra data show that the X-ray sources in the field are found in small clumps, with a clear concentration of more than 100 sources in the central cluster, called G49.5−0.4 (pan over the image to find this source.)

Although the W51 giant molecular cloud fills the entire field-of-view of this image, there are large areas where Chandra does not detect any diffuse, low energy X-rays from hot interstellar gas. Presumably dense regions of cooler material have displaced this hot gas or blocked X-rays from it.

One of the massive stars in W51 is a bright X-ray source that is surrounded by a concentration of much fainter X-ray sources, as shown in a close-up view of the Chandra image. This suggests that massive stars can form nearly in isolation, with just a few lower mass stars rather than the full set of hundreds that are expected in typical star clusters.

Another young, massive cluster located near the center of W51 hosts a star system that produces an extraordinarily large fraction of the highest energy X-rays detected by Chandra from W51. Theories for X-ray emission from massive single stars can't explain this mystery, so it likely requires the close interaction of two very young, massive stars. Such intense, energetic radiation must change the chemistry of the molecules surrounding the star system, presenting a hostile environment for planet formation.

A paper describing these results, led by Leisa Townsley (Penn State), appeared in the July 14th 2014 issue of The Astrophysical Journal Supplement Series and is available online: https://arxiv.org/abs/1403.2576

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

For more Chandra images, multimedia and related materials, visit:
http://www.nasa.gov/chandra

Credits:
X-ray: NASA/CXC/PSU/L. Townsley et al
Infrared: NASA/JPL-Caltech
Release Date: July 12, 2017

#NASA #Astronomy #Science #Space #MolecularCloud #W5 #Stars #Cosmos #Universe #Xray #Chandra #Observatory #Spitzer #JPL #MSFC #Marshall #UnitedStates #STEM #Education

Tuesday, July 11, 2017

Expedition 52 Red Square Visit


Expedition 52 flight engineers Paolo Nespoli of ESA, left, Sergey Ryazanskiy of Roscosmos, center, and Randy Bresnik of NASA visit Red Square to lay roses at the site where Russian space icons are interred as part of traditional pre-launch ceremonies, Monday, July 10, 2017 in Moscow. They will head to the Baikonur Cosmodrome in Kazakhstan July 16 for final pre-launch training. On July 28, 2017, Sergey Ryazanskiy, Randy Bresnik and Paolo Nespoli will launch to the International Space Station in a Russian Soyuz spacecraft. They will join the other three members of the Expedition 52 crew already on the station.

Credit: NASA/Bill Ingalls
Image Date: July 10, 2017


#NASA #ISS #Earth #Science #Cosmonaut #Soyuz #Commander #SergeyRyazanskiy #Astronaut #Astronauts #PaoloNespoli #RandyBresnik #ASI #ESA #Europe #Russia #Россия #Moscow #Mосква #RedSquare #Human #Spaceflight #Expedition52 #UnitedStates #JSC #STEM #Education

Monday, July 10, 2017

NASA’s James Webb Space Telescope ‘Hangs Out’ in Houston


July 10, 2017: Houston might have a high of 95 degrees Fahrenheit this week, but NASA’s James Webb Space Telescope will soon be hanging out in a vibration-isolating "hammock," with the best air conditioning available, courtesy of NASA’s Johnson Space Center in Houston.

In preparation for the Webb telescope’s upcoming cryogenic testing, engineers at Johnson have suspended it from the ceiling of the center’s historic Chamber A. This "hammock" (really, six support rods attached to the platform on which the telescope is sitting) is not for relaxation; it’s meant to isolate the telescope from the vibrations Chamber A could produce once the door closes and testing begins, as well as from disturbances that might occur outside the chamber.

James Webb Space Telescope primary mirror in Chamber A at NASA Johnson
NASA’s James Webb Space Telescope hangs from the ceiling of Chamber A at NASA’s Johnson Space Center in Houston.

“Remember that the system is designed to work in space, where the disturbances are highly controlled and only come from the spacecraft,” said Gary Matthews, an integration and testing engineer at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, who is testing the Webb telescope while it is at Johnson. “On Earth, we have to deal with all the ground-based disturbances, such as the pumps and motors, and even traffic driving by.”

You may have a hard time seeing the Webb telescope floating in the photo, because it is suspended only a few inches from the rails on the bottom of the chamber, which were used to roll the telescope into place.

What’s a hammock without a little bit of sway? With the telescope suspended, engineers conducted a "push test," where they gave it a very slight nudge and observed how it reacted to ensure the suspension system was functioning the best it could, said Matthews. Don’t worry, the 14,000 pound telescope wasn’t swinging from one side of the chamber to the other; the nudge only amounted to a few millimeters of movement.

Webb will remain suspended in the chamber for the entire cryogenic testing phase, which will last about three months. In space, the telescope must be kept extremely cold, in order to be able to detect the infrared light from very faint, distant objects. To protect the telescope from external sources of light and heat (like the sun, Earth and moon), as well as from heat emitted by the observatory, a five-layer, tennis court-sized sunshield acts like a parasol that provides shade. The sunshield separates the observatory into a warm, sun-facing side (reaching temperatures close to 185 degrees Fahrenheit) and a cold side (400 degrees below zero). The sunshield blocks sunlight from interfering with the sensitive telescope instruments.

The James Webb Space Telescope is the scientific successor to NASA's Hubble Space Telescope. It will be the most powerful space telescope ever built. Webb is an international project led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency.

For more information about Chamber A, visit: https://www.nasa.gov/feature/goddard/2017/nasas-apollo-era-test-chamber-now-james-webb-space-telescope-ready

For more information about the Webb telescope visit: www.jwst.nasa.gov or www.nasa.gov/webb

Credit: NASA/Chris Gunn
Release Date: July 10, 2017


#NASA #Astronomy #Science #Space #Telescope #JWST #JamesWebb #Exoplanets #Planets #Astrophysics #Cosmos #Universe #ESA #CSA #Goddard #GSFC #VacuumChamber #Cryogenic #Testing #JSC #Johnson #Houston #Texas #UnitedStates #STScI #STEM #Education

Thursday, July 06, 2017

Northern Canada: Lakes and Rivers Have Ice, Too | NASA



July 5, 2017: Icy lakes and rivers make a significant footprint on the Arctic landscape. Though widely dispersed, lakes cover as much as 40 to 50 percent of the land in many parts of the Arctic, and seasonal lake and river ice covers roughly 2 percent of all of Earth’s land surfaces. Since lakes and rivers have the highest evaporation rate of any surface in high latitudes, understanding and monitoring seasonal ice cover is critical to accurately forecasting the weather and understanding regional climate processes.

Lake and river ice also affects the people who live in the Arctic. Seasonal ice roads serve as a key transportation route for many communities. Ice jams can produce sudden and dangerous hazards to hydroelectric power facilities, infrastructure, and human settlements. Changing ice conditions make shipping and boating a challenge. And ice is involved in a range of hydrological processes that can affect the quality of drinking water.

Nonetheless, lake and river ice generally gets the least attention from ice scientists. According to one analysis, scientists publish roughly 50 scientific articles related to lake or river ice each year. In comparison, well over 600 articles get written about glaciers, 500 about snow, 350 about sea ice, and 250 about permafrost.

Satellites could help fill this gap. In fact, since the number of ground-based ice monitoring stations has declined since the 1980s, satellites offer one of the most promising means of monitoring lake and river ice over large areas, noted the authors of a book chapter about the state of lake and river ice research.

On May 29, 2017, the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite captured this image of ice covering the Amundsen Gulf, Great Bear Lake, and numerous small lakes in the northern reaches of Canada’s Northwest Territories and Nunavut. Sea ice generally forms in the Gulf of Amundsen in December or January and breaks up in June or July. Lake and river ice in this area follow roughly the same pattern, though shallow lakes freeze up earlier in the fall and melt earlier in the spring than larger, deeper lakes.

Image Credit: NASA Earth Observatory images by Joshua Stevens, using MODIS data from LANCE/EOSDIS Rapid Response
Story Credit: Adam Voiland
Instrument(s): Terra - MODIS
Image Date: May 29, 2017
Release Date: July 5, 2017


#NASA #Earth #Science #Space #Satellite #NorthwestTerritories #Nunavut #Arctic #Lakes #Rivers #Climate #ClimateChange #Aqua #MODIS #EarthObservation #RemoteSensing #STEM #Education

Apollo AS-203 Rocket Launch: July 5, 1966 | This Week in NASA History


This week in 1966, the AS-203 rocket launched from NASA’s Kennedy Space Center. This week in 1966, the AS-203 rocket launched from NASA’s Kennedy Space Center. The Apollo AS-203 mission was an uncrewed test of the vehicle’s second stage, the S-IVB stage, and the instrument unit of the Saturn V to obtain flight information under orbital conditions. The configuration of the Saturn IB was designed to match the Saturn V as closely as possible. NASA's Marshall Space Flight Center designed, developed and managed the production of the Saturn I and the Saturn V rocket that took astronauts to the moon.

Today Marshall is developing NASA's Space Launch System, the most powerful rocket ever built, that will be capable of sending astronauts deeper into space than ever before, including to Mars.

The NASA History Program is responsible for generating, disseminating, and preserving NASA’s remarkable history and providing a comprehensive understanding of the institutional, cultural, social, political, economic, technological, and scientific aspects of NASA’s activities in aeronautics and space.

Image Credit: NASA
Image Date: July 5, 1966
Release Date: July 5, 2017


#NASA #Space #Science #Apollo #Rocket #ApolloAS203 #SaturnIB #Moon #Lunar #SLS #SpaceLaunchSystem #Orion #Spacecraft #Mars #JourneyToMars #Human #Spaceflight #Kennedy #KSC #CapeCanaveral #Florida #UnitedStates #Exploration #SolarSystem #History #STEM #Education

Spiral Galaxy Messier 77: Wide-field image | European Southern Observatory


This image from the Digitized Sky Survey shows spiral galaxy Messier 77 and its surroundings. Messier 77 appears at the center and the edge-on galaxy NGC 1055 to its upper-right.

Credit: NASA/ESA, Digitized Sky Survey 2
Release Date: July 5, 2017


#ESO #Astronomy #Space #Science #Galaxy #Messier77 #NGC1068 #Barred #Spiral #TypeII #Seyfert #NGC1055 #Cetus #Cosmos #Universe #Telescope #VLT #Chile #Paranal #Observatory #Atacama #SouthAmerica #Europe #STEM #Education

Wednesday, July 05, 2017

Dazzling Spiral Galaxy with an Active Heart | European Southern Observatory


July 5, 2017: ESO’s Very Large Telescope (VLT) has captured a magnificent face-on view of the barred spiral galaxy Messier 77. The image does justice to the galaxy’s beauty, showcasing its glittering arms criss-crossed with dust lanes—but it fails to betray Messier 77’s turbulent nature.

This picturesque spiral galaxy appears to be tranquil, but there is more to it than meets the eye. Messier 77 (also known as NGC 1068) is one of the closest active galaxies, which are some of the most energetic and spectacular objects in the Universe. Their nuclei are often bright enough to outshine the whole of the rest of the galaxy. Active galaxies are among the brightest objects in the Universe and emit light at most, if not all, wavelengths, from gamma rays and X-rays all the way to microwaves and radiowaves. Messier 77 is further classified as a Type II Seyfert galaxy, characterised by being particularly bright at infrared wavelengths.

This impressive luminosity is caused by intense radiation blasting out from a central engine—the accretion disc surrounding a supermassive black hole. Material that falls towards the black hole is compressed and heated up to incredible temperatures, causing it to radiate a tremendous amount of energy. This accretion disc is thought to be enshrouded by thick doughnut-shaped structure of gas and dust, called a “torus”. Observations of Messier 77 back in 2003 were the first to resolve such a structure using the powerful VLT Interferometer.

This image of Messier 77 was taken in four different wavelength bands represented by blue, red, violet and pink (hydrogen-alpha) colors. Each wavelength brings out a different quality: for example, the pinkish hydrogen-alpha highlights the hotter and younger stars forming in the spiral arms, while in red are the fine, thread-like filamentary structures in the gas surrounding Messier 77 [1]. A foreground Milky Way star is also seen beside the galaxy center, displaying tell-tale diffraction spikes. Additionally, many more distant galaxies are visible; sitting at the outskirts of the spiral arms, they appear tiny and delicate compared to the colossal active galaxy .

Located 47 million light-years away in the constellation of Cetus (The Sea Monster), Messier 77 is one of the most remote galaxies of the Messier catalogue. Initially, Messier believed that the highly luminous object he saw through his telescope was a cluster of stars, but as technology progressed its true status as a galaxy was realized. At approximately 100,000 light-years across, Messier 77 is also one of largest galaxies in the Messier catalogue—so massive that its gravity causes other nearby galaxies to twist and become warped [2].

This image was obtained using the FOcal Reducer and low dispersion Spectrograph 2 (FORS2) instrument mounted on Unit Telescope 1 (Antu) of the VLT, located at ESO’s Paranal Observatory in Chile. It hails from ESO’s Cosmic Gems program, an outreach initiative that produces images of interesting, intriguing or visually attractive objects using ESO telescopes for the purposes of education and outreach.

Notes
[1] Similar red filaments are also found in NGC 1275. They are cool, despite being surrounded by a very hot gas at around 50 million degrees Celsius. The filaments are suspended in a magnetic field which maintains their structure and demonstrates how energy from the central black hole is transferred to the surrounding gas.

[2] NGC 1055 is located about 60 million light-years away. It is an edge-on galaxy, in contrast to Messier 77. This Astronomy Picture of the Day portrays both of them together, in a field of view about the size of the Moon (APOD).

Credit: European Southern Observatory (ESO)
Release Date: July 5, 2017


#ESO #Astronomy #Space #Science #Galaxy #Messier77 #NGC1068 #Barred #Spiral #TypeII #Seyfert #Cetus #Cosmos #Universe #Telescope #VLT #Chile #Paranal #Observatory #Atacama #SouthAmerica #Europe #STEM #Education

Titan's Colorful South Polar Vortex at Saturn | NASA Cassini


This true color image captured by NASA'S Cassini spacecraft before a distant flyby of Saturn's moon Titan on June 27, 2012, shows a south polar vortex, or a swirling mass of gas around the pole in the atmosphere of the moon.

The south pole of Titan (3,200 miles, or 5,150 kilometers, across) is near the center of the view.

Since Cassini arrived in the Saturn system in 2004, Titan has had a visible "hood" high above the north pole (see Haze Layers on Titan). It was northern winter at Cassini's arrival, and much of the high northern latitudes were in darkness. But the hood, an area of denser, high altitude haze compared to the rest of the moon's atmosphere, was high enough to be still illuminated by sunlight. The seasons have been changing since Saturn's August 2009 equinox signaled the beginning of spring in the northern hemisphere and fall in the southern hemisphere for the planet and its many moons. Now the high southern latitudes are moving into darkness. The formation of the vortex at Titan's south pole may be related to the coming southern winter and the start of what will be a south polar hood.

These new, more detailed images are only possible because of Cassini's newly inclined orbits, which are the next phase of Cassini Solstice Mission. Previously, Cassini was orbiting in the equatorial plane of the planet, and the imaging team's images of the polar vortex between late March and mid-May were taken from over Titan's equator. At that time, images showed a brightening or yellowing of the detached haze layer on the limb, or edge of the visible disk of the moon, over the south polar region.

Scientists think these new images show open cell convection. In open cells, air sinks in the center of the cell and rises at the edge, forming clouds at cell edges. However, because the scientists can't see the layer underneath the layer visible in these new images, they don't know what mechanisms may be at work.

Cosmic ray hits on the camera detectors appear as bright dots in the black and white version of the image.

Images taken using red, green and blue spectral filters were combined to create this natural color view. The images were obtained with the Cassini spacecraft narrow-angle camera late on June 26, 2012 at a distance of approximately 301,000 miles (484,000 kilometers) from Titan. Image scale is 2 miles (3 kilometers) per pixel.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colorado.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov .

Credit: NASA/JPL-Caltech/Space Science Institute/Kevin M. Gill
Release Date: July 10, 2012


#NASA #ESA #Astronomy #Science #Space #Saturn #Planet #Titan #Moon #Atmosphere #Polar #Vortex #SouthPole #SolarSystem #Exploration #Cassini #Spacecraft #JPL #Pasadena #California #UnitedStates #ASI #STEM #Education