• The low down
• Algol is a triple-star system, with a third star, Algol C, located a bit further out from the main pair, with a larger orbit.
• The brightening/dimming period of 2.867 days was first described by John Goodricke in 1783, although he did not know it was from one of the binary stars passing in front of the other
• Significance
• Egyptians were very nearly obsessive about studying the stars, apparently believing that doing so could help predict future events.
• A document known as the Cairo Calendar, shows that not only did the Egyptians know about Algol, but that their observations can be used to further explain the erratic behavior of the binary seen today
• Pulling the pattern from the calendar required a feat of statistical endurance. Eventually, the researchers uncovered two oscillations: a 29.6-day cycle, and a 2.85-day cycle
• The longer cycle is probably lunar. But at first, scientists weren’t sure what could have produced the shorter frequency.
• They found their match in the General Catalogue of Variable Stars
• * Of Note*
• The Cairo Calendar describes the binary period as 2.85 days; ever so slightly less than the 2.867 days now observed
• However, the team doesn’t believe this difference is due to error, they think it’s because the period has changed over time
• The three star system, could have slowed down a bit over the past three millennia because of magnetic interactions, stellar winds, or mass exchange
• Calculating the behavior of a three-body system with only 300 years of data, is problematic
• This new data Cairo Calendar could provide valuable data of the periodicity of the system from 3000 years ago, helping astronomers further refine current models
• Multimedia
• IMAGE : Eclipsing star .gif animation | astro.physics.uiowa.edu
• IMAGE : Star Chat location of Algol | nightskyinfo.com
• Further Reading / In the News
• Ancient Egyptians Tracked Eclipsing Binary Star Algol | Discovery News
• Did the ancient egyptians record the period of the eclipsing binary Algol – the Raging one? | Cornel Univsersity Library
• [Cairo Calendar shows Egyptians discovered binary Algol first | Phys.org](+ [Cairo Calendar shows Egyptians discovered binary Algol first | Phys.org)
• Ancient scribes may have banked on blinking binary | ScienceNews.org

*— NEWS BYTE — *

Black hole munching on stars

_{Image Credit: NASA, S. Gezari, A. Rest, and R. Chornock}

• The low down
• In June 2010, the researchers spotted a bright flare from the previously dormant black hole at the center of a galaxy approximately 2.7 billion light-years away.
• Over the next few months, the flare continued increasing in brightness a month after it was detected, then slowly faded over the next 12 months
• Significance
• Analyzing the spectrum of the ejected gas — that is, the specific colors making up its light the gas revealed it was mostly helium.
• The fact there was mostly helium and very little hydrogen in the gas suggests "the slaughtered star had to have been the helium-rich core of a stripped star
• This likely happened when the star went through the red giant phase, where it expanded to 100 times its original radius
• When it puffed up like that, it became vulnerable to the gravitational tidal forces of the black hole, and it would have been very easy to strip off the tenuous hydrogen envelope
• The star then had to approach much closer, 100 times closer in, before it was completely disrupted by the black hole
• * Of Note*
• Scientists now suggest that the light show was evidence of the black hole PS1–10jh shredding a star that wandered too close
• The black hole, weighing about 3 million solar masses, had probably already snacked on the star’s outer layers during a previous close encounter
• It also flung some of the stellar material into space
• Some of the partially ejected materials, eventually dumped back into the black hole, producing the observed, months-long flare.
• By measuring the rise of the flare’s brightness, the scientists calculated the rate at which the star’s gas was getting sucked into the black hole
• Those calculations helped reveal at what point and time the black hole had begun disrupting the star, revealing how powerful its gravitational field was and thus its mass, now estimated to be 3 million suns
• Multimedia
• YouTube VIDEO :Black Hole Devours Star – 139 Days of Stellar Devastation | VideoFromSpace
• IMAGE : Computer-simulated image shows gas from a tidally shredded star falling into a black hole [CREDIT: NASA, S. Gezari (The Johns Hopkins University, Baltimore, Md.), A. Rest (Space Telescope Science Institute, Baltimore, Md.), and R. Chornock (Harvard-Smithsonian Center for Astrophysics, Cambridge, Ma.)]
• Further Reading / In the News
• A star is torn | ScienceNews.org
• Monster Black Hole Caught Swallowing Unlucky Star | Space.com

See smog, think cows

_{Credit: NASA | Credit : USDA.gov}

• The low down
• People typically blame Southern California’s smog on automobiles, a new study suggests that cows may be just as responsible, if not more so
• A large fraction of the region’s smog, especially the particles smaller than 2.5 micrometers in diameter, is ammonium nitrate
• Ammonia is generated by cars with certain types of catalytic converters and by bacteria that consume cattle waste
• When the ammonia reacts with nitrogen oxides that are produced in large quantities in automobile emissions
• Significance
• Data gathered during low-altitude flights in and around the Los Angeles basin in May 2010 suggest that the region’s 9.9 million autos generate about 62 metric tons of ammonia each day
• White ammonia emissions from dairy farms in the eastern portion of the basin—home to about 298,000 cattle—range between 33 and 176 metric tons per day
• * Of Note*
• In addition ammonia emissions from the dairy farms are concentrated, boosting atmospheric levels of the gas to more than 100 times background levels
• So efforts to curb the farms’ emissions (perhaps by feeding the animals different diets) might reduce smog more than those targeting cars.
• Also theorized to contribute are vapors from paint, fumes from outdoor barbecues, and even the fresh scent emitted by trees
• Multimedia
• California Smog | NASA.gov
• Cow | USDA.gov [Photo by N. Wade Snyder]
• Further Reading / In the News
• Smog: It’s Not All Cars’ Fault | Science Magazine
• ScienceShot: There’s Cow in Your Smog | news.sciencemag.org

*— TWO-BYTE NEWS — *

Venus Transit Upcoming on June 5th / 6th

• * Last time on SciByte*
• Meteorites & Lasers | SciByte 38 – Venus Transit [March 20, 2012]
• Curiosity Rover | SciByte 22 – Science Calender [November 22, 2011]
• The low down
• On June 5 (June 6 in Australia and Asia), it will pass between the Earth and Sun… an event which only happens about twice and century and won’t happen again until the year 2117!
• The transit this year will last about 6.5 hours and will be visible from more than half of the Earth’s surface
• The Sun will set while the transit is still in progress from most of North America, the Caribbean, and northwest South America
• It will also already be in progress at sunrise for observers in central Asia, the Middle East, Europe, and eastern Africa
• No portion of the transit will be visible from Portugal or southern Spain, western Africa, and the southeastern 2/3 of South America
• Between each occurrence is happens at uneven occurrences at 121.5, then 8 then 105.5, then 8 years again. So only four times every 243 years and only in early Dec or early June
• The next pair of Venus transits occur over a century from now on 2117 Dec 11 and 2125 Dec 08
• * Of Note*
• You can start preparations now to view the transit of Venus
• Many retailers, like amazon, are are carrying special eclipse/transit viewing glasses and lenses
• Make sure all glasses are sealed and that no sunlight can enter
• Binoculars and telescopes require special lenses, if you have those you might want to practice before the event
• Start thinking about what time it will occur in your area
• Even the Hubble space telescope is getting in on the transit action by looking away from the Sun, more information on that in the SciByte near the transit.
• Multimedia
• YouTube VIDEO : NE Live – Transit of Venus Promo for Sun-Earth Day 2012 | SunEarthDay
• Further Reading / In the News
• Sun Earth Day
• 2012 Venus Transit – The Countdown Is On! | UniverseToday.com

*— VIEWER FEEDBACK — *

• SOFTWARE : MetalFreak
• “Stellarium is a free open source planetarium for your computer. It shows a realistic sky in 3D, just like what you see with the naked eye, binoculars or a telescope. It is being used in planetarium projectors. Just set your coordinates and go."
• Screenshots
• On stellarium.org you can download in Linux, Mac, or Windows
• [on cnet](https://download.cnet.com/Stellarium/3000–2054_4–10072276.html
• on Softpedia

SPACECRAFT UPDATE

SpaceX Dragon flight delay

• * Last time on SciByte*
• Mining Asteroids & Shuttle Discovery | SciByte 44 – SpaceX Falcon 9 Rocket [May 1, 2012]](https://original.jupiterbroadcasting.net/19186/mining-asteroids-shuttle-discovery-scibyte–44/)
• Solar Storms & Private Space Flight | SciByte 30 – SpaceX Space Station resupply mission resceduled [January 24, 2012]](https://original.jupiterbroadcasting.net/16276/solar-storms-private-space-flight-scibyte–30/)
• The low down
• On May 2nd it was announced that the launch will likely shift to a later date, possibly May 10
• A SpaceX spokesperson said that “SpaceX is continuing to work through the software assurance process with NASA. We will issue a statement as soon as a new launch target is set.”
• The flight was previously delayed from an April 30 launch date to allow more time for tests of Dragon’s flight software. The new delay is also meant to allow for further checkouts.
• Social Media
• SpaceX @SpaceX
• Further Reading / In the News
• SpaceX
• SpaceX Says Delay Likely for 1st Private Launch to Space Station | Space.com

SCIENCE CALENDER

Looking back

• May 9, 1893 : 119 years ago : First motion picture
  : The first motion picture exhibition was given by Thomas Alva Edison in Brooklyn, New York to an audience of 400 people at the Dept of Physics, Brooklyn Institute, Brooklyn, N.Y. using Edision’s Kinetograph. An optical lantern projector showed moving images of a blacksmith and his two helpers passing a bottle and forging a piece of iron. Each filmstrip had 700 images, each image being shown for 1/92 sec. The event was reported in the Scientific American of 20 May 1893.
• May 9, 1962 : 50 years ago : Moon reached by laser light : A laser beam was bounced off the moon from earth by MIT scientists. The area of the light beam on the surface was estimated at a diameter of 4 miles.

Looking up this week

• You may have seen …
• Supermoon pics from around the world, and Seattle

• Keep an eye out for …

• Wednesday May 9, 2012 : The Moon rises around midnight (5:40 GMT) tonight and stands due south at first light tomorrow. Scientists bounced a laser beam off the illuminated portion 50 years ago tonight.

• Friday, May 11 : Venus has been dropping lower in the west-northwest every evening.

• Saturday, May 12 : Last-quarter Moon rises in the middle of the night ( 5:47 EDT, 10:47 GMT)

• For deep sky objects this week check out universetoday.com

• Further Reading and Resources

• More on whats in the sky this week

• 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