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Mars Base

SpaceX's capsule arrives at ISS - 0 views

phys.org/...013-03-spacex-capsule-iss.html

scibyte84 dragon

shared by Mars Base on 03 Mar 13 - No Cached
  • 5:31 am EST (1031 GMT)
  • The capsule named Dragon was captured
  • The craft,
  • ...3 more annotations...
  • will now be inspected via cameras, brought to the Earth-facing port of the ISS's Harmony module and bolted into place by commands from mission control
  • SpaceX says it has 50 launches planned—both NASA missions and commercial flights—totaling about $4 billion in contracts
  • NASA also has a $1.9 billion resupply contract for the station with Orbital Sciences Corporation, which will launch the first test flight of its Antares rocket from a base in Virginia in the coming weeks
Mars Base

We Didn't Domesticate Dogs. They Domesticated Us. - 0 views

news.nationalgeographic.com/...tion-science-wolf-wolves-human

scibyte85 dog

shared by Mars Base on 03 Mar 13 - No Cached
  • hunting hypothesis, that humans used wolves to hunt, doesn't hold up either
  • Humans were already successful hunters without wolves, more successful than every other large carnivore.
  • The most common assumption is that some hunter-gatherer with a soft spot for cuteness found some wolf puppies and adopted them.
  • ...15 more annotations...
  • But when we look back at our relationship with wolves throughout history, this doesn't really make sense
  • the wolf was domesticated at a time when modern humans were not very tolerant of carnivorous competitors.
  • Most likely, it was wolves that approached us, not the other way around, probably while they were scavenging around garbage dumps on the edge of human settlements.
  • only the ones that were bold and friendly would have been tolerated.
  • Domestication gave them splotchy coats, floppy ears, wagging tails.
  • In only several generations, these friendly wolves would have become very distinctive from their more aggressive relatives.
  • Changes also happened to their psychology. These protodogs evolved the ability to read human gestures.
  • the ability of dogs to read human gestures is remarkable
  • chimpanzees and bonobos-can't read our gestures as readily as dogs can.
  • Dogs are remarkably similar to human infants in the way they pay attention to us.
  • People who had dogs during a hunt would likely have had an advantage over those who didn't.
  • Even today, tribes in Nicaragua depend on dogs to detect prey
  • Moose hunters in alpine regions bring home 56 percent more prey when they are accompanied by dogs
  • In the Congo, hunters believe they would starve without their dogs
  • Dogs would also have served as a warning system, barking at hostile strangers from neighboring tribes
Mars Base

SpaceX Dragon Recovers from Frightening Propulsion System Failure - Sunday Docking Set - 0 views

www.universetoday.com/...tem-failure-sunday-docking-set

scibyte84 dragon

shared by Mars Base on 03 Mar 13 - No Cached
  • By late Saturday afternoon sufficient recovery work had been accomplished to warrant NASA, ISS and SpaceX managers to give the go-ahead for the Dragon to rendezvous with the station early Sunday morning, March 3.
  • despite the one-day docking delay, the Dragon unberthing and parachute assisted return to Earth will still be the same day as originally planned on March 25.
  • There are numerous docking opportunities available in the coming days if SpaceX and NASA determined that more time was needed to gain confidence that Dragon could safely carry out an attempt.
  • ...1 more annotation...
  • the Dragon could stay on orbit for several additional months if needed
Mars Base

Mars Rover Curiosity Has First Big Malfunction - 0 views

news.nationalgeographic.com/...unction-science-space-nasa-jpl

scibyte84 Curiosity

shared by Mars Base on 02 Mar 13 - No Cached
  • hoped Curiosity would resume science work in about a week.
  • similar problems were caused by high-energy solar and cosmic ray strikes
  • On other space missions
  • ...6 more annotations...
  • Curiosity has protections against such high-energy disruptions, but the problem was compounded by what appears to have been the location of the strike—in the directory, or "table of contents," of the computer's memory
  • appears to have caused the computer to get stuck in an endless loop.
  • previous rovers experienced many so-called "anomalies" during the early part of their treks
  • Even if the rover is fully operational again in a week, the amount of science it can perform is limited.
  • the sun comes between Mars and the Earth in early April, partially blocking the path for radio commands for an entire month
  • The Curiosity team had planned to send back science data from Mars during that period—called "solar conjunction"—but had decided not to send up any commands.
Mars Base

SpaceX rocket launched, but problem with thrusters (Update 3) - 0 views

phys.org/...cket-flight-space-station.html

scibyte84 dragon

shared by Mars Base on 02 Mar 13 - No Cached
  • The problem cropped up immediately following Dragon's separation from the rocket upper stage, nine minutes into the flight.
Mars Base

SpaceX company fixes Dragon capsule problem - 0 views

phys.org/...ny-dragon-capsule-problem.html

scibyte84 dragon

shared by Mars Base on 02 Mar 13 - No Cached
  • The problem may have been caused by a stuck valve or a line blockage
  • An hour later, the Dragon was raised with the thrusters to a safe altitude.
  • It was the first serious trouble to strike a Dragon in orbit.
  • ...9 more annotations...
  • None of the four previous unmanned flights had any thruster issues
  • appeared to be a glitch versus a major concern.
  • Engineers for both SpaceX and NASA plan an exhaustive study before allowing the rendezvous to take place.
  • fresh fruit as well for the six station astronauts
  • Falcon 9 rocket performed "really perfectly" and that the thruster problem was isolated to the Dragon
  • On the previous flight in October, one of nine first-stage engines on the Falcon rocket shut down too soon
  • The capsule is designed to return to Earth with just two good sets of thrusters and, in "a super worst case situation," conceivably just one although it would be "a bit of a wobbly trip."
  • The newest Dragon is scheduled to spend more than three weeks at the space station before being cut loose by the crew
  • SpaceX plans to launch its next Dragon to the station in late fall.
Mars Base

Reseachers develop holographic technique for bionic vision - 0 views

medicalxpress.com/...c-technique-bionic-vision.html

scibyte84 BionicEye

shared by Mars Base on 27 Feb 13 - No Cached
  • Researchers
  • are testing the power of holography to artificially stimulate cells in the eye, with hopes of developing a new strategy for bionic vision restoration
  • optogenetics
  • ...16 more annotations...
  • uses gene therapy to deliver light-sensitive proteins to damaged retinal nerve cells
  • The basic idea of optogenetics is to take a light-sensitive protein from another organism, typically from algae or bacteria, and insert it into a target cell, and that photosensitizes the cell
  • Intense pulses of light can activate nerve cells newly sensitized by this gene therapy approach
  • researchers around the world are still searching for the best way to deliver the light patterns so that the retina "sees" or responds in a nearly normal way
  • The plan is to someday develop a prosthetic headset or eyepiece that a person could wear to translate visual scenes into patterns of light that stimulate the genetically altered cells.
  • The key, they say, is to use a light stimulus that is intense, precise, and can trigger activity across a variety of cells all at once.
  • The researchers turned to holography after exploring other options, including laser deflectors and digital displays
  • Digital light displays can stimulate many nerve cells at once, "but they have low light intensity and very low light efficiency
  • The genetically repaired cells are less sensitive to light than normal healthy retinal cells, so they preferably need a bright light source like a laser to be activated
  • Lasers give intensity, but they can't give the parallel projection
  • needed to see a complete picture
  • researchers have tested the potential of holographic stimulation in retinal cells in the lab
  • done some preliminary work with the technology in living mice with damaged retinal cells
  • The experiments show that holography can provide reliable and simultaneous stimulation of multiple cells at millisecond speeds.
  • implementing a holographic prosthesis in humans is far in the future
  • holography itself "also provides a very interesting path toward three-dimensional stimulation
Mars Base

Big Meteorite Discovered in Antarctica | Meteorites & Antarctica | Space.com - 0 views

www.space.com/eteorite-found-antarctica.html

scibyte84 meteorite

shared by Mars Base on 01 Mar 13 - No Cached
  • 40-pound (18 kilogram)
  • Initial tests show it is an ordinary chondrite, the most common type of meteorite found on Earth
  • This is the biggest meteorite found in East Antarctica for 25 years
  • ...9 more annotations...
  • More than 38,000 meteorites have been found in Antarctica, but only 30 bigger than 40 pounds (18 kg).
  • The Russian meteor that burst into fragments above the Chelyabinsk region on Feb. 15 is also an ordinary chondrite
  • charred black crust stands out
  • in the
  • snow, and the cold, dry climate helps preserve any organic chemicals inside the rocks
  • The expedition collected 425 meteorites in 40 days, with a total weight of 165 pounds (75 kg).
  • they may have found one Mars meteorite and one piece of the asteroid Vesta among the many discoveries.
  • A team from Belgium and Japan discovered the
  • meteorite as the members drove across the East Antarctic plateau on snowmobiles
Mars Base

Mars Science Laboratory: Computer Swap on Curiosity Rover - 0 views

mars.jpl.nasa.gov/...index.cfm

scibyte84 Curiosity

shared by Mars Base on 01 Mar 13 - No Cached
  • 02.28.2013
  • The ground team for NASA's Mars rover Curiosity has switched the rover to a redundant onboard computer in response to a memory issue on the computer that had been active
  • intentional swap at about 2:30 a.m. PST today (Thursday, Feb. 28) put the rover
  • ...16 more annotations...
  • "safe mode."
  • , into
  • safe mode to operational status over the next few days and is troubleshooting the condition that affected operations
  • The condition is related to a glitch in flash memory linked to the other, now-inactive, computer.
  • switched computers to get to a standard state from which to begin restoring routine operations
  • Like many spacecraft
  • Curiosity carries a pair of redundant main computers in order to have a backup available if one fails
  • Each of the computers, A-side and B-side, also has other redundant subsystems linked to just that computer
  • Curiosity is now operating on its B-side, as it did during part of the flight from Earth to Mars. It operated on its A-side from before the August 2012 landing through Wednesday.
  • While
  • resuming operations on the B-side, we are also working to determine the best way to restore the A-side as a viable backup
  • The spacecraft remained in communications at all scheduled communication windows on Wednesday, but it did not send recorded data, only current status information.
  • status information revealed that the computer had not switched to the usual daily "sleep" mode when planned
  • Diagnostic work in a testing simulation at JPL indicates the situation involved corrupted memory at an A-side memory location used for addressing memory files
  • Scientific investigations by the rover were suspended Wednesday
  • Resumption of science investigations is anticipated within several days
Mars Base

Big Meteorite Chunk Found in Russia's Ural Mountains - 0 views

www.universetoday.com/...ound-in-russias-ural-mountains

scibyte84 RussianMeteor

shared by Mars Base on 27 Feb 13 - No Cached
  • More than 100 fragments have been found so far that appear to be from the space rock
  • now scientists
  • have discovered the biggest chunk so far, a meteorite fragment weighing more than one kilogram (2.2 lbs).
  • ...4 more annotations...
  • Fragments of the meteorite have been found along a 50 kilometer (30 mile) trail under the meteorite’s flight path
  • Small meteorites have also been found in an eight-meter (25 feet) wide crater in the region’s Lake Chebarkul
  • believes there are more to be found, including a possible biggest chunk that he says may lie at the bottom of Lake Chebarkul. It could be up to 60cm in diameter
  • This video from NASA explains more
Mars Base

Comet PanSTARRS: How to See it in March 2013 - 0 views

www.universetoday.com/...rs-how-to-see-it-in-march-2013

scibyte83 scibyte84

shared by Mars Base on 23 Feb 13 - No Cached
  • we could have the first naked eye comet of 2013 for northern hemisphere observers in early March
  • if it performs
  • The projected brightness curve
  • ...21 more annotations...
  • Panoramic Survey Telescope and Rapid Response System (PanSTARRS) based on the summit of Haleakala on the island of Maui
  • comet brightened ahead of expectations and was first picked up by an amateur astronomer on March 28th of last year
  • Comet PanSTARRS is already an impressive sight for southern hemisphere observers
  • Comet PanSTARRS will then begin curving northward during the last week of February
  • the comet has a hyperbolic orbit inclined 84.2° degrees relative to the ecliptic
  • On an 110,000+ year orbit, this is more than likely Comet PanSTARRS first journey through the inner solar system
  • Comet PanSTARRS will reach an altitude of greater than 5° at dusk for northern hemisphere observers based around 30° north latitude looking low to the southwest starting on March 5th.
  • The comet will then begin gaining altitude
  • Keep in mind, Daylight Saving Time begins
  • looking for the comet around 7:00 pm local on the first week of March, it’ll be at 8:00 pm on the second week
  • After gaining
  • elevation from our northern hemisphere vantage point
  • will then begin running roughly parallel to the western horizon on each successive evening for mid-northern latitude observers
  • This first half of March is also when Comet PanSTARRS will have the potential to appear at its brightest
  • best case scenario, we’ll have a comet with a -1st magnitude coma and a tail pointing straight up from the horizon like an exclamation point.
  • worst case situation, we’ll have a +3rd magnitude fuzzy comet only visible through binoculars
  • if you observe the comet on no other night, be sure to check it out on the evening of March 12-13th
  • will be joined by a slim crescent Moon just over a day old.
  • Comet PanSTARRS will then continue its trek northward
  • for the remainder of March
  • By May 1st, Comet PanSTARRS will have dipped back down below naked eye visibility
Mars Base

Nearby Ancient Star is Almost as Old as the Universe - 0 views

www.universetoday.com/...-almost-as-old-as-the-universe

scibyte84

shared by Mars Base on 24 Feb 13 - No Cached
  • A metal-poor star located merely 190 light-years from the Sun is 14.46+-0.80 billion years old, which implies that the star is nearly as old as the Universe
  • results emerged from a new study
  • Such metal-poor stars are (super) important to astronomers because they set an independent lower limit for the age of the Universe
  • ...21 more annotations...
  • can be used to corroborate age estimates inferred by other means
  • In the past, analyses of globular clusters and the Hubble constant
  • yielded vastly different ages for the Universe, and were offset by billions of years
  • based on the microwave background and Hubble constant, but it must have formed soon after the big bang
  • Within the errors, the age of HD 140283 does not conflict with the age of the Universe, 13.77 ± 0.06 billion years
  • Metal-poor stars can be used to constrain the age of the Universe because metal-content is typically a proxy for age
  • Heavier metals are generally formed in supernova explosions, which pollute the surrounding interstellar medium.
  • Stars subsequently born from that medium are more enriched with metals than their predecessors
  • each successive generation becoming increasingly enriched
  • HD 140283 exhibits less than 1% the iron content of the Sun, which provides an indication of its sizable age.
  • had been used previously to constrain the age of the Universe, but uncertainties tied to its estimated distance (at that time) made the age determination somewhat imprecise
  • obtain a new and improved distance for HD 140283 using the Hubble Space Telescope (HST), namely via the trigonometric parallax approach
  • distance uncertainty for HD 140283 was significantly reduced by comparison to existing estimates, thus resulting in a more precise age estimate for the star
  • The reliability of the age determined is likewise contingent on accurately determining the sample’s metal content
  • analyses of globular clusters and the Hubble constant yielded vastly different ages for the Universe
  • discrepant ages stemmed partly from uncertainties in the cosmic distance scale
  • determination of the Hubble constant relied on establishing (accurate) distances to galaxies
  • One of the key objectives envisioned for HST was to reduce uncertainties associated with the Hubble constant to <10%, thus providing an improved estimate for the age of the Universe
  • the mean implying an age near ~14 billion years
  • Determining a reliable age for stars in globular clusters is likewise contingent on the availability of a reliable distance
  • the study reaffirms that there are old stars roaming the solar neighborhood which can be used to constrain the age of the Universe
Mars Base

Lawmakers Vote to Rename NASA Dryden After Neil Armstrong | Space.com - 0 views

www.space.com/rmstrong-nasa-center-name.html

scibyte84

shared by Mars Base on 27 Feb 13 - No Cached
  • The U.S. House of Representatives has voted to rename a NASA flight research center after the late Neil Armstrong, the first man to walk on the moon
  • was approved unanimously in the House, calls for NASA's Dryden Flight Research Center in southern California to be renamed the Neil A. Armstrong Flight Research Center.
  • also renames the surrounding Western Aeronautical Test Range after Hugh L. Dryden to continue honoring the aeronautical engineer.
  • ...8 more annotations...
  • Dryden was the visionary behind NASA's X-15 rocket plane and the Apollo program. Neil Armstrong was the one who flew the spacecraft Dryden envisioned
  • This is at least the third time since 2007 that the House of Representatives has tried to rename the NASA center after Armstrong
  • the bill now passed in the House, it will be referred on to the Senate for consideration
  • Dryden recommended to President John F. Kennedy that the goal of putting a man on the moon within 10 years was achievable and something the American people could rally behind
  • Neil Armstrong, flying with his Apollo 11 crewmates Buzz Aldrin and Michael Collins, accomplished Kennedy's goal of landing on the moon
  • Armstrong died Aug. 25 at age 82 following complications resulting from cardiovascular procedures
  • Dryden was not able to see his dream become reality, as he died in 1965
  • honor both men's legacies by naming the Flight Research Center after Neil Armstrong and the surrounding Test Range after Hugh Dryden
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