We take a look at hint of dark matter, reading your dreams, blackhole snacks, spacecraft updates, Curiosity news, and as always take a peek back into history and up in the sky this week.
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Show Notes:
Hints of Dark Matter
- After two years a cosmic ray detector (Alpha Magnetic Spectrometer, AMS) on the International Space Station has found the first tantalizing evidence of the cosmic footprints that may have been left by dark matter
- Dark Matter
- A type of matter hypothesized to account for 26.8% of the total mass in the universe
- Its existence and properties are inferred from its gravitational effects on visible matter, radiation, and the large-scale structure of the universe
- First theorized in 1932, the existence of dark matter for 80 years but has never actually observed it directly
- Accelerators smashing particles together at high speed deep underground with special detectors have had no luck finding them, you can also look in space for the results of rare dark matter collisions
- Unraveling the mystery of dark matter could help scientists better understand the composition of our universe and, more particularly, what holds galaxies together
- Alpha Magnetic Spectrometer | AMS
- The Alpha Magnetic Spectrometer, AMS, is a 7-ton detector with a 3-foot magnet ring at its core was sent into space in 2011, transmitting its data to CERN, where it is being analyzed
- Since its installation on 19 May 2011 it has measured over 30 billion cosmic rays at energies up to trillions of electron volts
- Its permanent magnet and array of precision particle detectors collect and identify charged cosmic rays passing through AMS from the far reaches of space
- Over its long duration mission on the ISS, AMS will record signals from 16 billion cosmic rays every year and transmit them to Earth for analysis by the AMS Collaboration.
- Data
- Currently, the total number of positrons identified by AMS, in excess of 400,000, is the largest number of energetic antimatter particles directly measured and analyzed from space
- In the initial 18 month period of space operations, from 19 May 2011 to 10 December 2012, AMS analyzed 25 billion primary cosmic ray events
- Of these, 6.8 million, were unambiguously identified as electrons and their antimatter counterpart, positrons.
- If particles of dark matter crash and annihilate each other, they should leave a footprint of positrons-the anti-matter version of electrons-at high energy levels
- The results show evidence that could be dark matter or could be energy could also originate from pulsars
- By measuring the ratio between positrons and electrons and by studying the behavior of any excess across the energy spectrum, a better understanding of the origin of dark matter and other physics phenomena can be obtained
- The curve of the plot of those positrons will be a clue as to what these results are, if the curve is one shape, it points to dark matter, while if it\’s another, it points to pulsars
- While the results aren\’t enough to declare the case closed they expect a more definitive answer in a matter of months
- Multimedia
- YouTube | Installing the AMS | Space Station Live: First Findings from the AMS | ReelNASA
- YouTube | Anouncement | Space Station Instrument Finds Excess Antimatter | NASAtelevision
- YouTube | Animated Look inside the AMS | Sifting Through the Cosmic Sands for Dark Matter | VideoFromSpace
- Further Reading / In the News
- Scientists report hint of dark matter in first results from $2 billion cosmic ray detector (Update 4) | Phys.org
- Cosmic ray detector confirms hints of dark matter | Matter & Energy | Science News
- Dark Matter Possibly Found by $2 Billion Space Station Experiment | AMS | Space.com
- Potential Dark Matter Discovery a Win for Space Station Science | Space.com
— NEWS BYTE —
Peering Into Your Dreams
- A recent study shows that it may be possible to use brain activity patterns to understand something about what a person is dreaming about
- The Study
- Researchers recorded brain activity in three adult male volunteers during the early stages of sleep
- Researchers chose to awaken the subjects in light sleep rather than in deeper \”rapid eye movement\” (REM) sleep solely to make the research easier to do
- It takes at least an hour to reach first REM stage, it would be difficult to get sleep and dream data from multiple participants
- Right after being awakened from the early stages of sleep, the researchers asked for detailed reports on what they had seen while sleeping
- After gathering at least 200 such reports from the three men, the researchers used a lexical database to group the dreamed objects in coarse categories, such as street, furniture and girl
- They used functional MRI to monitor brain activity of the participants and polysomnography to record the physical changes that occur during sleep
- Then researchers compared evidence of brain activity when participants were awake and looking at real images to the brain activity they saw when participants were dreaming
- Computer algorithms sorted through the patterns of brain activity, linking particular patterns with objects
- On average, the computer could pick which of two objects had appeared in a dream 70 percent of the time
- What the Results Could Mean
- The study bolsters the notion that the vivid imagery of dreams, no matter how fantastic, is as real as waking life, from the brain’s perspective
- Visual experiences you have when dreaming are detectable by the same type of brain activity that occurs when looking at actual images when you\’re awake
- However it might be hard to remember a dream minutes after waking up, because particular neurotransmitters or brain regions involved in memory are not active during sleep
- There is also evidence suggesting that the pattern of spontaneous brain activity is relevant to health issues
- Caution Belief
- The current approach requires the data of image viewing and sleep within the same person, but methods are being developed for aligning brain patterns across people
- One expert said the results are intriguing, he was cautious that previous disappointments relating brain activity to complex visual experience and would like to see this replicated
- Multimedia
- YouTube | This is your brain on dreams | Digtal Carlisle
- Further Reading / In the News
- Dream contents deciphered by computer | Body & Brain | Science News
- Could scientists peek into your dreams? | MedicalXPress
— TWO-BYTE NEWS —
Blackhole Snacks on a Planet
- Astronomers using the Integral space observatory were able to watch as the planet was eaten by a blackhole that had been inactive for decades
- The Galaxy
- Astronomers were using Integral to study a different galaxy when they noticed a bright X-ray flare coming from another location in the same wide field-of-view
- The origin was confirmed as NGC 4845, 47 million light-years away, a galaxy never before detected at high energies
- The blackhole in the center of NGC 4845 is estimated to have a mass of around 300,000 times that of our own Sun
- The \’Eaten\’ Object
- The halo of material suggest that the object was approximately 14–30 Jupiter masses, and so the astronomers say the object was either a super-Jupiter or a brown dwarf
- It is believed that it was a ‘wandering’ planet, which would fit the description of recent studies
- Astronomers estimate that only the external layers, ~10% total mass, were eaten by the blackhole, and that a denser core has been left orbiting the blackhole
- The Emissions
- The emission was traced from its maximum in January 2011, when the galaxy brightened by a factor of a thousand, and then as it subsided over the course of the year
- Emissions brightened and decayed with a delay of 2–3 months between the object being disrupted and the heating of the debris in the vicinity of the blackhole.
- By analyzing the characteristics of the flare astronomers were able to determine the source of the emission
- This data came from a halo of material around the galaxy’s central blackhole as it tore apart and fed on the object
- Of Note
- This is the first time where we have seen the disruption of a substellar object by a blackhole
- This \’event\’ might be similar to what is expected to happen with the supermassive blackhole at the center of our own Milky Way Galaxy
- Estimates are that events like these may be detectable every few years in galaxies around us
- Multimedia
- YouTube | blackhole Snacks On A Super-Jupiter | Animation | VideoFromSpace
- Further Reading / In the News
- Astronomers Watch as a blackhole Eats a Rogue Planet | UniverseToday.com
— VIEWER FEEDBACK —
Eyeing Europa
- **Paul Hill @P_H_9_3 | Check This Out! **
- Jupiter Europa Mission Funding
- A resolution was recently passed by the House and Senate outlining the extent of government funding (75,000,000) for pre-formulation and/or formulation activities for a mission that meets the science goals outlined for the Jupiter Europa mission
- Data recently uncovered the presence of magnesium sulfate salt, Epsom salt, on Europa’s surface which is suggestive of a cycling of Europa’s salty ocean with the surface.
- Although this is good news, it’s also a reminder that potentially habitable moons don’t only orbit Jupiter, Enceladus the Saturnian moon is known to possess salty liquid water beneath its surface, plus an internal heat source, that generates Enceladus’ famous geysers
- Europa In Other News
- According to research Jupiter’s ice-encrusted moon Europa has hydrogen peroxide across much of the surface of its leading hemisphere, which could potentially provide energy for life if it has found its way into the moon’s subsurface ocean.
- The availability of oxidants like peroxide on Earth was a critical part of the rise of complex, multicellular life
- The highest concentration of peroxide found was on the side of Europa that always leads in its orbit around Jupiter,roughly 20 times more diluted than \’off the shelf\’ hydrogen peroxide, then drops off to nearly zero on the hemisphere of Europa that faces backward in its orbit.
- The concentration of Hydrogen peroxide was first detected on Europa by NASA’s Galileo mission, which explored the Jupiter system from 1995 to 2003
- Galileo observations were of a limited region. The new Keck data show that peroxide is widespread across much of the surface of Europa, and the highest concentrations are reached in regions where Europa’s ice is nearly pure water with very little sulfur contamination
- Scientists think hydrogen peroxide is an important factor for the habitability of the global liquid water ocean under Europa’s icy crust because hydrogen peroxide decays to oxygen when mixed into liquid water
- With high enough levels of compounds like peroxide could help to satisfy the chemical energy requirement needed for life within the ocean, if the peroxide is mixed into the ocean
- Further Reading / In the News
- Will the Europa Clipper Cruise to Jupiter\’s Moon? | Discovery News
- Hydrogen Peroxide Could Feed Life on Europa | UniverseToday.com
— SPACECRAFT UPDATE—
Reviewing SpaceX’s Dragon Spacecraft Glitch
- Last Time on SciByte
- SciByte 84 (March 5, 2013)| HIV & SpaceX Troubles – SpaceX – Dragon Space Station Resupply Mission Glitch
- March 1, 2013 Launch Glitch
- Barely 11 minutes after the March 1 blastoff of the Dragon atop the SpaceX Falcon 9 rocket from Cape Canaveral, Florida contact had been lost
- Right after spacecraft separation in low Earth orbit, a sudden and unexpected failure of the Dragon’s critical thrust pods had prevented three out of four from initializing and firing
- What Happened
- The oxidizer pressure was low in three tanks, which is required to orient the craft for two way communication and to propel the Dragon to the orbiting lab complex
- The problem was that three of the check valves had a small design change to the check valves by the supplier that would have needed a magnifying glass to see the difference, because of the tiny change they got stuck
- SpaceX had run the new check valves through a series of low pressurization systems tests and they worked well and didn’t get stuck, but SpaceX did not run the functional tests at higher pressures
- Solution
- The team was able to write some new software in real time to build pressure upstream of the check valves and then released that pressure
- SpaceX had difficulty communicating with the spacecraft because it was in free drift in orbit
- They worked closely with the Air Force to get higher intensity, more powerful dishes to communicate with the spacecraft and upload the software
- The solution got the valves unstuck and then they worked well
- In the meantime SpaceX will revert to the old check valves and run tests to make sure this failure doesn’t happen again
- Multimedia
- YouTube SpaceX Dragon Carrying NASA Cargo Arrives at International Space Station | NASATelevision
- Further Reading / In the News
— CURIOSITY UPDATE —
- Parachute
- An animation of seven images from the HiRISE camera on the Mars Reconnaissance Orbiter show a “flapping” of the parachute that allowed the Curiosity rover to descend safely through Mars atmosphere images
- The images were acquired by HiRISE between August 12, 2012 and January 13, 2013
- The different images show distinct changes in the parachute, which is attached to the backshell that encompassed the rover during launch, flight and descent
- This type of motion may kick off dust and keep parachutes on the surface bright, to help explain why the parachute from Viking 1 (landed in 1976) remains detectable
- Argon Readings
- Curiosity\’s Sample Analysis at Mars (SAM) instrument analyzed an atmosphere sample that found that the Martian atmosphere has about four times as much of a lighter stable isotope (argon-36) compared to a heavier one (argon-38)
- This data is what we would expect to see with the theory that Mars lost much of its original atmosphere by a process of gas escaping from the top of the atmosphere
- The results provided the the clearest and most precise measurements ever made of isotopes of argon in the Martian atmosphere, isotopes are variants of the same element with different atomic weights
- The ratio is much lower than the solar system\’s original ratio, as estimated from argon-isotope measurements of the sun and Jupiter which points to a process at Mars that favored preferential loss of the lighter isotope over the heavier one
- The data also removes previous uncertainty about the ratio in the Martian atmosphere from 1976 measurements from NASA\’s Viking project and from small volumes of argon extracted from Martian meteorites
- Daily Atmospheric Measurements
- Curiosity measures several variables with the Rover Environmental Monitoring Station (REMS), daily air temperature
- While temperature measurements have climbed steadily since the measurements began eight months ago and is not strongly tied to the rover\’s location, the humidity has differed significantly at different places along the rover\’s route
- In addition the REMS sensors detected many whirlwind patterns during the first hundred Martian days of the mission, though not as many as detected in the same length of time by earlier missions although no trails of dust devils have not been seen inside Gale Crater
- Upcoming
- For the rest of April, Curiosity will carry out daily activities for which commands were sent in March, using DAN, REMS and the Radiation Assessment Detector (RAD).
- Curiosity will be drilling into another rock where the rover is now, but that target has not yet been selected. The science team will discuss this over the conjunction period
- Multimedia
- Image Galleries at JPL and Curiosity Mulimedia
- Social Media
- Curiosity Rover @MarsCuriosity
- Further Reading / In the News
- Watch Curiosity’s Parachute Flap in the Martian Breeze | UniverseToday.com
- Remaining Martian Atmosphere Still Dynamic | mars.jpl.nasa.gov
SCIENCE CALENDAR
Looking back
- April 13, 2000 : 13 years ago : Oldest mouse Born : The mouse Yoda was born, and became the world\’s oldest mouse on his fourth birthday in 2004 (which at 1,462-days-old compares to about 136 in human-years). A dwarf mouse, Yoda lives with a larger female cage mate (Princess Leia) to provide him with protective body warmth. The life span of the average laboratory mouse is slightly over two years. Yoda lives in the laboratory of Dr Richard A. Miller, a professor of pathology in the Geriatrics Center of the University of Michigan Medical School, an expert on the genetics and cell biology of aging. For his studies, he has developed strains of mice, derived from wild mice captured in Idaho, that live longer, stay smaller and age more slowly than ordinary mice
- World\’s Oldest Mouse Reaches Milestone Birthday, Teaches Scientists About Human Aging (Apr 13, 2004) | ScienceDaily
Looking up this week
- Keep an eye out for …
- Wed, Apr 10 | 10 pm and later | The \”Summer Star\” Vega rises in the NE
- Wed, Apr 10 | New Moon
- Sat, Apr 13 | ~ 1 hour after sunset | The crescent Moon is in the West with Jupiter to it\’s upper left.
- Sat, Apr 13 | ~ 1 hour after sunset | The Crescent Moon is also between the Pleiades star cluster to its right and slightly below and the red giant star Aldebaran to it\’s upper left.
- Saturn | Rises in the E-SE at the end of twilight,
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Jupiter | After Sunset it is seen high in the W sky, dropping closer to the horizon as the evening goes on, climbing to it\’s highest point in the S around 2am DST
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Further Reading and Resources
- Sky&Telescope
- SpaceWeather.com
- StarDate.org
- For the Southern hemisphere: SpaceInfo.com.au
- Constellations of the Southern Hemisphere : astronomyonline.org
- Royal Astronomical Society of New Zealand : rasnz.org.nz
- AstronomyNow
- HeavensAbove