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Featured B "Space and Stuff"

  1. Nov 23, 2016 #101

    Imager

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  2. Nov 23, 2016 #102
    Possibly it's not actually blue, but the image has been digitally enhanced to give maximum contrast.
     
  3. Nov 23, 2016 #103

    Imager

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    I found some other images and the impact appears as dark gray to black with the surface of Mars in light gray. I’m guessing they were black and white shots.

    Would that gold back ground in the image posted indicate color enhancements?
     
  4. Nov 23, 2016 #104
    If the aim of digitally processing was to get maximum contrast, it's quite likely that the background tones are altered as well.
    However it does look close to the sort of tones in pictures of the landscape taken by the Curiosity rover.
    Though I'm pretty sure that a lot of those are enhanced too.
     
  5. Nov 23, 2016 #105
  6. Nov 24, 2016 #106

    Imager

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    Below is from the PDF, not that I understand most of it, but it does appear to be blue enhanced. None of my Google searches tied PSP_005000_1000_RGB.NOMAP.JP2 to the image I posted, but then no one ever said I knew what I was doing...

    PSP_005000_1000_RGB.NOMAP.JP2 3-color image consisting of RED, BG, and synthetic blue images. The BG image has been warped to line up with the RED.NOMAP image. The BG (blue-green) bandpass primarily accepts green light. The synthetic blue image digital numbers (DNs) consist of the BG image DN multiplied by 2 minus 30% of the RED image DN for each pixel. This is not unique data, but provides a more appealing way to display the color variations present in just two bandpasses, RED and BG.
     
  7. Nov 24, 2016 #107

    nsaspook

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    http://www.esa.int/Our_Activities/S...aparelli_landing_investigation_makes_progress

    This looks like a sensor bounds check problem combined with a signed/unsigned math under/overflow error.
     
  8. Nov 24, 2016 #108

    mfb

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    Ah, the good old one-sided comparison. "if altitude < 1 km, release parachute". "The altitude is minus 1000 km? Okay, release parachute."

    Always catch cases where something goes completely wrong, predict out which input is more likely to be wrong, then ignore that.
     
  9. Nov 24, 2016 #109
    Why is the event horizon of a black hole so cold? I thought when matter is compressed, it causes it to heat up do to friction.
     
  10. Nov 25, 2016 #110

    mfb

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    The event horizon is not an object, and it is not made out of matter. It is a region in spacetime. Questions like this would fit better to our relativity forum.
     
  11. Nov 28, 2016 #111

    1oldman2

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    This is interesting, it seems large deposits of water may be fairly common on several bodies in our solar system.
    http://www.nature.com/nature/journal/vaop/ncurrent/full/nature20120.html

    http://www.nature.com/nature/journal/vaop/ncurrent/full/nature20148.html

    https://spaceflightnow.com/2016/11/...-be-counted-among-solar-systems-ocean-worlds/

    Scientists believe they can explain how an ocean of water is lurking beneath an ice sheet inside Pluto’s prominent heart-shaped region, an iconic frozen landscape discovered during the New Horizons spacecraft’s flyby last year.

    A slushy buried sea under the icy plains of Sputnik Planitia would help counterbalance the gravitational weight of the dwarf planet’s largest moon Charon, which stays fixed above the opposite side of Pluto, researchers reported last week in the journal Nature.
     
    Last edited by a moderator: May 8, 2017
  12. Nov 29, 2016 #112

    1oldman2

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    ExoMars has been testing the imaging system and the results are awesome.
    http://www.bbc.com/news/science-environment-38147682
    "We saw Hebes Chasma at 2.8 metres per pixel," said Nicolas Thomas, the camera's principal investigator from the University of Bern, Switzerland.

    "That's a bit like flying over Bern at 15,000km/h and simultaneously getting sharp pictures of cars in Zurich."


    November 30th marks the beginning of the end for Cassini, begins setting up for the ultimate "crash and burn". The 183rd main engine burn should be the last with all following maneuvers performed with thrusters. Nearly 20 years, this has to be one of the most successful missions to date.
    http://www.jpl.nasa.gov/news/news.php?feature=6681

    Between Nov. 30 and April 22, Cassini will circle high over and under the poles of Saturn, diving every seven days -- a total of 20 times -- through the unexplored region at the outer edge of the main rings.

    During these orbits, Cassini will pass as close as about 56,000 miles (90,000 kilometers) above Saturn's cloud tops. But even with all their exciting science, these orbits are merely a prelude to the planet-grazing passes that lie ahead. In April 2017, the spacecraft will begin its Grand Finale phase.

    During its grand finale, Cassini will pass as close as 1,012 miles (1,628 kilometers) above the clouds as it dives repeatedly through the narrow gap between Saturn and its rings, before making its mission-ending plunge into the planet's atmosphere on Sept. 15. But before the spacecraft can leap over the rings to begin its finale, some preparatory work remains.


    And now a note from the "dark side" of space. (I'll bet no one saw this coming :sorry:)
    http://www.cnn.com/2016/11/28/politics/space-war-us-military-preparations/index.html

    China and Russia are taking aim at America in space with a dizzying array of weapons seemingly borrowed from science fiction. Russia has deployed what could be multiple kamikaze satellites such as "Kosmos 2499" -- designed to sidle up to American satellites and then, if ordered, disable or destroy them. China has launched the "Shiyan" -- equipped with a grappling arm that could snatch US satellites right out of orbit.

    "We have very good surveillance and intelligence capabilities, so we can see the threats that are being built," said Hyten. "So we're developing capabilities to defend ourselves. It's really that simple."
     
  13. Nov 29, 2016 #113

    mfb

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    Ah, the peaceful US using space for civilian and defense purposes only, while Russia and China think about nothing but harming the US. Yeah, sure.
    One should tell the author about undersea cables, which also handle the vast majority of intercontinental data transfer because their bandwidth is so much better than satellite communication.
    Nothing but speculations. Russia launched a satellite that moved away from its upper rocket stage, then later approached it again. So what? Every docking maneuver at space stations looks similar - and Russia has a lot of experience with those.
    According to Russia it is a test of a new propulsion system.
    You cannot "snatch US satellites right out of orbit". Shiyan-7 made slow approaches to two different satellites. It is reported to have an arm.
    A robotic an arm is a key component for larger space stations, like the one China wants to build.
    A robotic arm is an ridiculously stupid way to attack satellites. Destroying them with high-speed impacts is much easier and much more effective than grappling anything. Yes it create space debris, but not that much, and with grappling arms you are limited to 1-2 satellites per grappling satellite which is a stupid ratio.
    Of course you say "no" if saying "yes" means your funding gets reduced.
     
  14. Nov 30, 2016 #114

    1oldman2

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    There was a certain amount of irony in my comment "The darkside of space" considering the source CNN was quoting.

    http://www.space.com/25275-x37b-space-plane.html
    The U.S. Air Force's unmanned X-37B space plane has flown three clandestine missions to date, carrying secret payloads on long-duration flights in Earth orbit.

    NASA transferred the project to the U.S. military in 2004 - specifically, the Defense Advanced Research Projects Agency (DARPA). At that point, X-37 became a classified project.

    The X-37B program is now run by the Air Force's Rapid Capabilities Office, with mission control for orbital flights based at the 3rd Space Experimentation Squadron at Schriever Air Force Base in Colorado. The space planes are built by Boeing's Phantom Works division.

    http://www.space.com/9940-secretive-space-plane-meet-37b.html#ooid=lnMnR4cDqNSqpOCj1kbS3mTdnAuJ_zGF


    https://www.rt.com/politics/space-militarization-us-russia-699/
    The United States is moving toward the militarization of space and this will change the face of war in the near future, an academician with the Russian Academy of Engineering Sciences has warned.

    Only the United States and Israel abstained from voting on the document, rendering it effectively toothless.

    Washington’s refusal to cede control of space likely stems from its increasing reliance on space-based systems: An estimated 90 percent of the US Military reportedly uses or depends on space-based systems.

    The Russian academic referred the shock over China’s successful targeted destruction of an old orbiting weather satellite in 2007.


    https://www.scientificamerican.com/article/war-in-space-may-be-closer-than-ever/
    The world’s most worrisome military flashpoint is arguably not in the Strait of Taiwan, the Korean Peninsula, Iran, Israel, Kashmir or Ukraine. In fact, it cannot be located on any map of Earth, even though it is very easy to find. To see it, just look up into a clear sky, to the no-man’s-land of Earth orbit, where a conflict is unfolding that is an arms race in all but name.

    https://www.stratfor.com/video/militarization-space
    http://www.globalsecurity.org/space/library/report/1989/DCA.htm

    This is a big problem here whenever the government is involved.
     
  15. Nov 30, 2016 #115

    mfb

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    What are the other 10% and why don't they use GPS?
    Statements like that are misleading. They suggest some super-advanced system where everything depends on specialized satellites, while in reality it just means every mobile electronic device has GPS.
    Oh well, I stopped hoping for somewhat reasonable rt.com content long ago.
     
  16. Nov 30, 2016 #116

    1oldman2

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    RT isn't one of my regular sources for linking, I used that one in the interest of symmetry, you know to balance out the American news sources spin. :wink:

    I'm glad I read https://www.physicsforums.com/insights/vacuum-fluctuation-myth/ before I read
    http://www.space.com/34852-neutron-star-shows-quantum-property-evidence.html


    A strange quantum phenomenon predicted more than 80 years ago finally may have been observed in nature.

    In classical physics, a vacuum is entirely empty, but in quantum physics, there are "virtual particles" that are constantly appearing and vanishing in the vacuum of space. Heisenberg and Euler used a theory called quantum electrodynamics (QED) to show how the quantum properties of a vacuum would influence light waves.


    This I found rather cool also. :smile:
    http://www.space.com/34850-private-moon-race-apollo-17-site.html
    A Berlin-based group of rocket scientists and engineers are aiming to land a pair of privately funded Audi-branded robotic rovers on the moon and drive them to inspect NASA's Apollo 17 lunar roving vehicle, marking 45 years since humans last drove on another world.
    ptscientists-moon-rover-apollo17b.jpg
     
  17. Nov 30, 2016 #117

    davenn

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    you mite want to reread what you wrote there and offer an edited version :wink:
    it isn't valid in it's current form


    edit ... not your fault, noting of course it's the bad reporting that is incorrect

    They are combing robotic rovers and manned rovers into the one sentence without clarifying the situation


    Dave
     
    Last edited: Nov 30, 2016
  18. Nov 30, 2016 #118

    1oldman2

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    :sorry: Gets me every time. Thanks dave. :smile:
    I've decided not to edit as an example of what can be found in professional literature these days, it is a cool concept... Audi will have some good PR for there ad dept. :cool:
     
    Last edited: Nov 30, 2016
  19. Nov 30, 2016 #119

    davenn

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    yeah it seems, at times, there is little proof reading done :frown:
     
  20. Nov 30, 2016 #120

    Filip Larsen

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    It is not obvious to me what type of issue with the news story you and davenn are referring to. Is it just bad english (for some reason) or is there something more seriously wrong with it?
     
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