Thursday, June 21, 2018

Hubble proves Einstein correct on galactic scales

Most precise general relativity test outside Milky Way
June 21, 2018: An international team of astronomers using the NASA/ESA Hubble Space Telescope and the European Southern Observatory’s Very Large Telescope has made the most precise test of general relativity yet outside our Milky Way. The nearby galaxy ESO 325-G004 acts as a strong gravitational lens, distorting light from a distant galaxy behind it to create an Einstein ring around its centre. By comparing the mass of ESO 325-G004 with the curvature of space around it, the astronomers found that gravity on these astronomical length-scales behaves as predicted by general relativity. This rules out some alternative theories of gravity.

Image of Einstein ring:
An image of the nearby galaxy ESO 325-G004, created using data collected by the NASA/ESA Hubble Space Telescope and the MUSE instrument on the ESO’ Very Large Telescope. MUSE measured the velocity of stars in ESO 325-G004 to produce the velocity dispersion map that is overlaid on top of the Hubble Space Telescope image. Knowledge of the velocities of the stars allowed the astronomers to infer the mass of ESO 325-G004. The inset shows the Einstein ring resulting from the distortion of light from a more distant source by intervening lens ESO 325-004, which becomes visible after subtraction of the foreground lens light.

Using the NASA/ESA Hubble Space Telescope and European Southern Observatory’s Very Large Telescope (VLT), a team led by Thomas Collett (University of Portsmouth, UK), was able to perform the most precise test of general relativity outside the Milky Way to date.

The theory of general relativity predicts that objects deform spacetime, causing any light that passes by to be deflected and resulting in a phenomenon known as gravitational lensing. This effect is only noticeable for very massive objects. A few hundred strong gravitational lenses are known, but most are too distant to precisely measure their mass. However, the elliptical galaxy ESO 325-G004 is amongst the closest lenses at just 450 million light-years from Earth.

Using the MUSE instrument on the VLT the team calculated the mass of ESO 325-G004 by measuring the movement of stars within it. Using Hubble the scientists were able to observe an Einstein ring resulting from light from a distant galaxy being distorted by the intervening ESO 325-G004. Studying the ring allowed the astronomers to measure how light, and therefore spacetime, is being distorted by the huge mass of ESO 325-G004.

Collett comments: “We know the mass of the foreground galaxy from MUSE and we measured the amount of gravitational lensing we see from Hubble. We then compared these two ways to measure the strength of gravity—and the result was just what general relativity predicts, with an uncertainty of only nine percent. This is the most precise test of general relativity outside the Milky Way to date. And this using just one galaxy!”

General relativity has been tested with exquisite accuracy on Solar System scales, and the motions of stars around the black hole at the centre of the Milky Way are under detailed study, but previously there had been no precise tests on larger astronomical scales. Testing the long range properties of gravity is vital to validate our current cosmological model.

These findings may have important implications for models of gravity alternative to general relativity. These alternative theories predict that the effects of gravity on the curvature of spacetime are “scale dependent”. This means that gravity should behave differently across astronomical length-scales from the way it behaves on the smaller scales of the Solar System. Collett and his team found that this is unlikely to be true unless these differences only occur on length scales larger than 6000 light-years.

“The Universe is an amazing place providing such lenses which we can use as our laboratories,” adds team member Bob Nichol (University of Portsmouth). “It is so satisfying to use the best telescopes in the world to challenge Einstein, only to find out how right he was.”

The Hubble Space Telescope is a project of international cooperation between ESA and NASA.

This research was presented in a paper entitled “A precise extragalactic test of General Relativity” by Collett et al., to appear in the journal Science.

The international team is comprised of: Thomas E. Collett (Institute of Cosmology and Gravitation, University of Portsmouth, UK), Lindsay J. Oldham (Institute of Astronomy, University of Cambridge, UK, and Harvard College, Harvard-Smithsonian Center for Astrophysics, USA), Russell Smith (Centre for Extragalactic Astronomy, University of Durham, UK), Matthew W. Auger (Institute of Astronomy, University of Cambridge, UK), Kyle B. Westfall (ICG, Portsmouth, UK, and University of California, Santa Cruz, USA), David Bacon (ICG, Portsmouth, UK), Robert C. Nichol (ICG, Portsmouth, UK), Karen L. Masters (ICG, Portsmouth, UK), Kazuya Koyama (ICG, Portsmouth, UK) and Remco van den Bosch (Max Planck Institute for Astronomy, Garching, Germany).

Credit: ESO, ESA/Hubble, NASA
Release Date: June 21, 2018


#NASA #Hubble #ESO #Astronomy #Space #Science #Einstein #Relativity #GeneralRelativity #EinsteinRing #Lens #Galaxy #ESO325G004 #Cosmos #Universe #Telescope #VLT #ESA #GSFC #Goddard #STScI #STEM #Education #Infographic

Wednesday, June 20, 2018

Outpost | International Space Station




ESA Astronaut Alexander Gerst: "7 Billion people live on the planet beneath us. 6 single souls live in space. Unbelievable!"
-
"Außenposten. Auf dem Planeten unter uns leben 7 Milliarden Menschen. Im Weltraum leben 6 Menschen. Unglaublich!"

Follow Alexander and the Horizons mission:
http://bit.ly/AlexanderGerstESA and on bit.ly/HorizonsBlogESA

Credit: Alexander Gerst/European Space Agency (ESA)
Release Date: June 20, 2018


#NASA #Space #ISS #Science #Earth #Humanity #Astronaut #AlexanderGerst #Horizons #Europe #Germany #Deutschland #Expedition56 #Human #Spaceflight #Spacecraft #Photography #STEM #Education #International #OrbitalPerspective #OverviewEffect

Tuesday, June 19, 2018

Humanity's Cradle | NASA

NASA astronaut Drew Feustel is pictured tethered to the International Space Station just outside of the Quest airlock during a spacewalk he conducted with fellow NASA astronaut Ricky Arnold (out of frame) on June 14, 2018. During the six-hour, 49-minute spacewalk the duo installed high-definition cameras to provide enhanced views of commercial crew spacecraft, including the SpaceX Crew Dragon and the Boeing Starliner, as they approach and dock with the orbital laboratory.

Credit: NASA/JSC
Image Date: June 14, 2018


#NASA #Space #ISS #Science #Earth #Astronaut #Astronauts #Spacewalk #EVA #DrewFeustel #RickyArnold #SpaceX #CrewDragon #Boeing #Starliner #UnitedStates #Expedition56 #Human #Spaceflight #Spacecraft #JSC #Houston #Texas #STEM #Education

Earth View | Soyuz Spacecraft

ESA Astronaut Alexander Gerst: "The first photo I took out the window of our Soyuz after launch. I have no idea where it is. But I was surprised to see the Earth move much faster in the lower Soyuz orbit, compared to ISS."

Follow Alexander and the Horizons mission:
http://bit.ly/AlexanderGerstESA and on bit.ly/HorizonsBlogESA

Credit: Alexander Gerst/European Space Agency (ESA)
Release Date: June 18, 2018


#NASA #Space #ISS #Science #Earth #Soyuz #SoyuzMS09 #Союз #Astronaut #AlexanderGerst #Horizons #Europe #Germany #Deutschland #Expedition56 #Human #Spaceflight #Spacecraft #Photography #STEM #Education #International #OrbitalPerspective #OverviewEffect

Monday, June 18, 2018

Horizon | International Space Station

Alexander: "Horizon. Today, first day off after some of the busiest 10 days in my life. I thought long about which should be my first photo from space. When I saw this sunrise, I immediately knew this would be it. What a fascinating planet!"

Follow Alexander and the Horizons mission:
http://bit.ly/AlexanderGerstESA and on bit.ly/HorizonsBlogESA

"Horizont. Heute erster freier Tag nach zehn Tagen durcharbeiten. Habe lange überlegt, welches mein erstes Foto aus dem All sein sollte. Als ich diesen Sonnenaufgang gesehen habe, wusste ich die Antwort. Was für ein faszinierender Planet!"

Credit: European Space Agency (ESA)/NASA
Release Date: June 18, 2018


#NASA #Space #ISS #Science #Earth #Sunrise #Astronaut #AlexanderGerst #Horizons #Europe #Germany #Deutschland #Expedition56 #Human #Spaceflight #Spacecraft #Photography #STEM #Education #International #OrbitalPerspective #OverviewEffect

Crew Dragon Dreams | SpaceX Tribute Poster

Goal: Launching NASA Astronauts from U.S. Soil
Dragon 2.0. This is the next hurdle for SpaceX.
Learn more: www.spacex.com/crew-dragon
Commercial Crew: "The manned version of the Dragon spacecraft that has been successfully carrying cargo to the ISS for some time now. I believe there will be a high altitude abort test where a Falcon rocket will carry the Dragon to right before staging and perform an abort. I don't think this has been done before. During the Apollo program a special small rocket called "Little Joe" that used solid rocket motors took the Apollo spacecraft to enough height and speed where the test took place. More recently they just take off right from the ground (as with the Orion) and this test has already been performed on the Dragon."

"The motors used for abort on Dragon are built into the walls of the spacecraft rather than mounted on top and this is just one more step in the evolution of modern spacecraft."

"In looking at some of the pics above I notice they show a manned Dragon being launched by a Falcon Heavy. I'm not sure that is ever going to happen. In a way the Falcon 2.0 is already obsolete. The work on the BFR (or BFS) is now the main task taking place at SpaceX and it seems to be going well so far. If it works as expected then it will be a far safer and more reliable way of getting into space. The Falcon 2.0 will only be used until the big rocket is operational and that may be as soon as 2021 or 2022. To me this all seems to be happening at an incredible pace. It is very exciting and I have great confidence in the crew at SpaceX to get this job done."

Credit: Bill Davis
Release Date: June 17, 2018


#NASA #SpaceX #Space #ISS #Moon #Mars #Dragon #CrewDragon #Astronauts #Spacecraft #Falcon #Rocket #BFR #BFS #SolarSystem #Exploration #ElonMusk #JourneyToMars #Commercial #LaunchAmerica #KSC #UnitedStates #STEM #Education #Poster #Future #Colonization #Planet

Sunday, June 17, 2018

Martian Dust Storm | Hubble

What's happened to Mars? In 2001, Mars underwent a tremendous planet-wide dust storm—one of the largest ever recorded from Earth. To show the extent, these two Hubble Space Telescope storm watch images from late June and early September (2001) offer dramatically contrasting views of the martian surface. At left, the onset of smaller "seed" storms can be seen near the Hellas basin (lower right edge of Mars) and the northern polar cap. A similar surface view at right, taken over two months later, shows the fully developed extent of the obscuring global storm. Although this storm eventually waned, in recent days a new large dust storm has been taking hold of the red planet.

Image Credit: J. Bell (ASU), M. Wolff (Space Science Inst.), Hubble Heritage Team (STScI/AURA), NASA
Release Date: June 17, 2018


#NASA #Hubble #Space #Astronomy #Mars #RedPlanet #Planet #DustStorm #Telescope #ESA #Goddard #STScI #STEM #Education #APoD

Saturday, June 16, 2018

Inside NASA's Kennedy Space Center! | Week of June 15, 2018


This week in space news, a SpaceX Dragon cargo spacecraft will resupply the International Space Station with a launch from Cape Canaveral Air Force Station in Florida later this month. NASA's Ice, Cloud, and land Elevation Satellite-2, or ICESat-2, arrived at Vandenberg Air Force Base in California on Tuesday.

Credit: Kennedy Space Center (KSC)
Duration: 1 minute, 43 seconds
Release Date: June 15, 2018


#NASA #Space #Earth #ISS #SpaceX #Dragon #Cargo #Spacecraft #Earth #ICESat2 #ClimateChange #GlobalWarming #Environment #Kennedy #KSC #Florida #Spaceport #UnitedStates #STEM #Education #HD #Video
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    NASA Administrator Chats with Astronauts | This Week @NASA – June 15, 2018

    Administrator Bridenstine chats with a couple of our astronauts, a massive dust storm on Mars, and astronauts at work outside the space station. . .a few of the stories to tell you about – This Week at NASA!

    Credit: National Aeronautics and Space Administration
    Duration: 3 minutes, 39 seconds
    Release Date: June 15, 2018

    #NASA #Space #Earth #Moon #Mars #Planet #DustStorm #ISS #Astronauts #EVA #Spacewalk #JoeAcaba #MarkVandeHei #Bridenstine #Administrator #UnitedStates #Expedition56 #Human #Spaceflight #JourneyToMars #Spacecraft #Aerospace #Aircraft #STEM #Education #HD #Video

    NASA's Space to Ground | Week of June 15, 2018

    NASA's Space to Ground is your weekly update on what's happening aboard the International Space Station. Expedition 56 Commander Drew Feustel and Flight Engineer Ricky Arnold of NASA completed the sixth spacewalk at the International Space Station this year at 2:55 p.m. EDT, lasting 6 hours, 49 minutes on Thursday, June 14, 2018. The two astronauts installed new high-definition cameras that will provide enhanced views during the final phase of approach and docking of the SpaceX Crew Dragon and Boeing Starliner commercial crew spacecraft that will soon begin launching from American soil.

    They also swapped a camera assembly on the starboard truss of the station, closed an aperture door on an external environmental imaging experiment outside the Japanese Kibo module, and completed two additional tasks to relocate a grapple bar to aid future spacewalkers and secured some gear associated with a spare cooling unit housed on the station’s truss.

    This was the 211th spacewalk in support of assembly and maintenance of the unique orbiting laboratory where humans have been living and working continuously for nearly 18 years. Spacewalkers have now spent a total of 54 days, 23 hours and 29 minutes working outside the station.

    During the ninth spacewalk of Feustel’s career, he moved into third place for total cumulative time spent spacewalking with a total of 61 hours and 48 minutes. It was Arnold’s fifth spacewalk with a total time of 32 hours and 4 minutes.

    Credit: NASA's Johnson Space Center
    Duration: 2 minutes, 41 seconds
    Release Date: June 15, 2018


    #NASA #Space #ISS #Science #Earth #Astronauts #Spacewalk #EVA #DrewFeustel #RickyArnold #SpaceX #CrewDragon #Boeing #Starliner #ESA #DLR #AlexanderGerst #Europe #Germany #Deutschland #SerenaAuñónChancellor #UnitedStates #Expedition56 #Human #Spaceflight #Spacecraft #JSC #Houston #Texas #STEM #Education #HD #Video

    Friday, June 15, 2018

    A New Mars Impact Crater | NASA MRO

    June 15, 2018: This HiRISE image from NASA's Mars Reconnaissance Orbiter (MRO) captures a new, dated (within about a decade) impact crater that triggered a slope streak. When the meteoroid hit the surface and exploded to make the crater, it also destabilized the slope and initiated this avalanche.

    The crater itself is only 5 meters across, but the streak it started is 1 kilometer long! Slope streaks are created when dry dust avalanches leave behind dark swaths on dusty Martian hills. The faded scar of an old avalanche is also visible to the side of the new dark streak.

    The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colorado. NASA's Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the Mars Reconnaissance Orbiter Project for NASA's Science Mission Directorate, Washington.

    Credit: NASA/JPL-Caltech/University of Arizona
    Release Date: June 15, 2018


    #NASA #Mars #Space #Astronomy #Science #Geology #Meteor #ImpactCrater #Crater #Meteoroid #Landscape #Terrain #Geoscience #RedPlanet #MRO #Reconnaissance #Orbiter #Spacecraft #HiRISE #Camera #JPL #STEM #Education

    Mars: Dune Ripples in Hellas Planitia | NASA

    On the Migration of Ripples in Hellas Planitia — This is part of a large dune field inside the western rim of Hellas Planitia. The field is located at an elevation that is deeper than most dune fields at this latitude. How does that impact ripple migration?

    Mars Reconnaissance Orbiter (MRO) image
    (258 km above the surface, less than 1 km top to bottom and north is to the right.)

    The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colo. NASA's Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the Mars Reconnaissance Orbiter Project for NASA's Science Mission Directorate, Washington.

    Credit: NASA/JPL/University of Arizona
    Release Date: June 13, 2018


    #NASA #Mars #Space #Astronomy #Science #Geology #HellasPlanitia #Dunes #Landscape #Terrain #Geoscience #RedPlanet #MRO #Reconnaissance #Orbiter #Spacecraft #HiRISE #Camera #JPL #STEM #Education

    Thursday, June 14, 2018

    Large Unmanned NASA Aircraft Flies Solo

    Ikhana Flies in Public Airspace Without Chase Plane for First Time
    NASA’s remotely-piloted Ikhana aircraft performs flight tests in preparation to fly in the National Airspace System without a safety chase aircraft. On June 12, 2018, NASA successfully flew the historic flight.

    The flight will help to move the United States one step closer to normalizing unmanned aircraft operations in the airspace used by commercial and private pilots. The Ikhana aircraft is based at NASA’s Armstrong Flight Research Center in Edwards, California.

    Credit: NASA/Armstrong Flight Research Center
    Duration: 2 minutes, 4 seconds
    Release Date: June 14, 2018


    #NASA #Earth #Planet #Atmosphere #Ikhana #Aircraft #Unmanned #UAS #UAV #Drone #Aviation #Aerospace #Armstrong #Edwards #AirForce #AFB #California #UnitedStates #Technology #Engineering #STEM #Education #HD #Video

    Wednesday, June 13, 2018

    Martian Dust Storm | NASA Curiosity Rover


    June 13, 2018: These two views from NASA’s Curiosity rover, acquired specifically to measure the amount of dust inside Gale Crater, show that dust has increased over three days from a major Martian dust storm. The left-hand image shows a view of the east-northeast rim of Gale Crater on June 7, 2018 (Sol 2074); the right-hand image shows a view of the same feature on June 10, 2018 (Sol 2077). The images were taken by the rover’s Mastcam.

    Credit: NASA/JPL-Caltech/MSSS
    Release Date: June 13, 2017


    #NASA #Mars #Astronomy #Science #Space #Curiosity #Rover #GaleCrater #Planet #Atmosphere #Dust #DustStorm #Weather #Mastcam #Exploration #RedPlanet #JPL #Pasadena #California #USA #UnitedStates #STEM #Education #Infographic

    Massive Martian Dust Storm | NASA/JPL

    Opportunity Rover Hunkers Down in Dust Storm

    A massive Martian dust storm is seriously affecting operations of the agency’s Opportunity rover, which has been operating on the Martian surface for over 14 years. Scientists are now learning from various Mars missions currently operating to study this unprecedented event.

    Animation: This series of images shows simulated views of a darkening Martian sky blotting out the Sun from NASA’s Opportunity rover’s point of view, with the right side simulating Opportunity’s current view in the global dust storm (June 2018).

    The storm is one of the most intense ever observed on the Red Planet. As of June 10, it covered more than 15.8 million square miles (41 million square kilometers)—about the area of North America and Russia combined. It has blocked out so much sunlight, it has effectively turned day into night for Opportunity, which is located near the center of the storm, inside Mars' Perseverance Valley.

    Opportunity Rover Launched: July 7, 2003

    For more information about Opportunity, visit:
    http://www.nasa.gov/rovers
    http://marsrovers.jpl.nasa.gov

    Credit: NASA/JPL-Caltech/TAMU/Arizona State University
    Release Date: June 13, 2017

    #NASA #Mars #Astronomy #Science #Space #Opportunity #Rover #PerseveranceValley #Planet #Atmosphere #DustStorm #Weather #Exploration #RedPlanet #Sunlight #SolarPower #JPL #Pasadena #California #USA #UnitedStates #STEM #Education #Simulation