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Milky Way

Due to the Milky Way's gravity, it attracts other local galaxies to it. Therefore, nearby galaxies will eventually collide with the Milky Way, making one larger galaxy and destroying some stars in the process. The process is known as galactic cannibalism and will not happen to the Milky Way for another 3 billion years.Space.com: Galactic cannibalism

updated 2010-07-17 15:45:27

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Interferometry

When two light waves interfere, they combine depending on what phase they are in. If one wave's peak is aligned with the other's trough, they cancel each other out (destructive interference). However, if both peaks and troughs are aligned, then a new wave will be formed with a greater amplitude (constructive interference).http://www.space.com/scienceastronomy/astronomy/interferometry_101.html The amplitude will increase by the sum of the original two amplitudes plus double the square root of the multiplication of both amplitudes. http://docs.google.com/viewer?a=v&q=cache:EhQiK86DrC8J:www.optics.arizona.edu/jcwyant/Short_Courses/SIRA/2-BasicInterferometryAndOpticalTesting.pdf+interferometry+basics&hl=en&gl=us&pid=bl&srcid=ADGEESjNBlHvUv9yPOAOxWelulIAgZ-Cb_NBJeiiV1kkryiymR3s8mamlY-v3JMJFTtlWRa6SswZNhBqTcnqSIRF4pFAtWm_MeK9N3oIG3wZM7vq_So0uIJBchhlVf0SLg4jmJfVGbr8&sig=AHIEtbQYMxhxUEIpYwZURTx15yMSFMLY9w

In an interferometer, the path of both waves is constructed in such a way to maximize the amplitude. http://outreach.atnf.csiro.au/education/senior/astrophysics/interferometry.html#interfoptical http://www.europhysicsnews.org/index.php?option=com_article&access=standard&Itemid=129&url=/articles/epn/pdf/2001/06/epn01613.pdf The wave, after interference, is displayed as a series of dark and bright lines. http://docs.google.com/viewer?a=v&q=cache:EhQiK86DrC8J:www.optics.arizona.edu/jcwyant/Short_Courses/SIRA/2-BasicInterferometryAndOpticalTesting.pdf+interferometry+basics&hl=en&gl=us&pid=bl&srcid=ADGEESjNBlHvUv9yPOAOxWelulIAgZ-Cb_NBJeiiV1kkryiymR3s8mamlY-v3JMJFTtlWRa6SswZNhBqTcnqSIRF4pFAtWm_MeK9N3oIG3wZM7vq_So0uIJBchhlVf0SLg4jmJfVGbr8&sig=AHIEtbQYMxhxUEIpYwZURTx15yMSFMLY9w Most people are familiar with this as the "slit" experiment. http://www.space.com/scienceastronomy/astronomy/interferometry_101.html The slits will be brighter than the original beam. Many different aberrations can occur in the resulting pattern, which can be due ...

updated 2010-10-16 00:36:29

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Sudan Asteroid

On October 5, 2008, an asteroid on a collision course with earth was identified by astronomers at Catalina Sky Survey observatory in Tucson, Arizona.National Geographic: Boulder-Size Asteroid ... (October 6, 2008) The event should mark the first time that astronomers have been able to successfully predict an asteroid impact.MSNBC: Small asteroid to burn up over Africa(October 6, 2008) Expected to explode harmlessly in the atmosphere over Sudan, the asteroid will reach earth's atmosphere about 10:46 p.m. EDT, 2:46 a.m. October 7th, GMT.Sky & Telescope: Major Bolide Forecast Tonight... (October 6, 2008)

updated 2010-07-17 23:01:25

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NASA Shrimp

Last November, NASA had a pleasant surprise, while they were drilling a hole in the Antarctic Ice, performing an experiment on inhospitable living conditions. After drilling a hole of 600 feet in the Antarctic ice shelf, NASA had lowered a cable into the hole, with a camera attached. At a depth of 600 feet, when they broke through the Ice Shelf, a small shrimp hovered through the view of the camera. The footage of the shrimp, with the Latin name Lyssianasid amphipod, was released to YouTube on March 16, 2010.

In the 2:14 minute long video, the viewer is treated with an backwards view, facing the surface (which is only a black hole, because of the distance). One can see the rope, which the camera is hanging on, and the contours of the hole, with a regular chopped surface, from the drill. After some ten seconds, an orange creature swims into view, from the right-top corner. The creature swims around, and can be easily identified as a shrimp when it examines the rope. The shrimp leasurely swims around, before swimming out of view again. At that point, the camera is lowered through the hole again, showing the exit point under the ice shelf, where the shrimp is seen once again, before descending further down.

According to reports, the shrimp wasn't the only discovery made, as also a tentacle, presumably belonging to a jellyfish was found and retrieved. The discovery of the shrimp and tentacle has sparked discussion of ...

updated 2010-07-17 16:34:18

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Asteroids Pass By Earth

Scientists at NASA say asteroids and other small objects frequently pass by the Earth on a regular basis. Lindley Johnson, who heads up NASA's "Near Earth" Program, told Discovery News that "Objects this small pass by Earth pretty frequently," adding that even if the asteroids were to hit Earth, they'd likely break apart in our atmosphere and "They wouldn't do any damage."http://news.discovery.com/space/asteroids-earth-moon-distance.html

Of the objects that do pass near the Earth, about one-fifth of them are big enough in size to cause concern. According to Discovery News, "about 20 percent of the known near-Earth objects are considered potentially hazardous" because they are large and because their orbits take them "within 4.6 million miles of the planet."http://news.discovery.com/space/asteroids-earth-moon-distance.html

updated 2010-09-09 01:06:54

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Archaeoastronomy

A study of the Pyramids of Giza reveals that the ancient Egyptians were familiar with mathematical astronomy. The researchers believe the two main pyramids, Cheops and Chephren, were a planned project related to the movement of planetary objects. The Great Pyramid of Giza, Cheops, was aligned with various objects in the ancient sky -- Orion's Belt, Sirius and the circumpolar stars.

Some researchers speculate that Serpent Mound functioned as a calendar for the Adena people.http://www.highlandssanctuary.org/Serpent_Mound_Visitors_Guide.htm The earthwork has alignments to the Equinox sunrise, Winter Solstice sunrise, Summer Solstice sunset and Summer Solstice sunrise.http://www.ohiohistory.org/ http://texasnativeskies.org/sites/site.php?s=4

In 1963, Gerald Hawkins, an astronomer at Boston University and the Harvard-Smithsonian Observatory, suggested that Stonehenge was an astronomical calculator.http://www.nytimes.com/2003/07/26/us/gerald-hawkins-75-astronomer-who-theorized-on-stonehenge.html The stones are not only "aligned with solar and lunar astronomical events", but can also predict eclipses.http://witcombe.sbc.edu/stonehenge/archaeoastronomy.html http://www.archaeoastronomy.com/stonehenge.html

updated 2010-12-20 16:08:10

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Chandra X-ray Observatory

• 1976: The Advanced X-ray Astrophysics Facility (AXAF) project is proposed to NASA

• 1992: Initial spacecraft design is downscaled to reduce increasing costs

• 1998: Project is renamed Chandra X-ray Observatory in honor of Subrahmanyan Chandrasekhar

• July 23, 1999: Chandra X-ray Observatory is deployed in space by shuttle Columbia flight STS-93

• 2007: The spacecraft celebrates its eight year of operation

updated 2012-05-12 20:06:54

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UFO

• BBC: UFO quizzes -- Test your TV, film, Sci-fi UFO type knowledge, or take a more challenging UFO expert test.

• MSNBC: Test your knowledge of UFO lore -- How familiar are you with history of alien sightings?

• Can you answer these questions? -- If you think the above quizzes were just too easy, try this one!

updated 2010-07-18 01:21:07

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Spitzer Space Telescope

• 1983: NASA solicits proposals to build a large Shuttle-based Infrared Telescope Facility (SIRTF).

• 1984: Results from precursor IRAS mission lead NASA to pursue a long duration, free-flying observatory.

• 1991: Under severe budget restrictions, SIRTF goes through three redesign cycles.

• 1993: A Delta rocket is selected as the launch vehicle for Spitzer instead of the Space Shuttle.

• August 25, 2003: SIRTF is launched into space atop a Delta 7920H.

• December 18, 2003: NASA renames SIRTF in honor of American astrophysicist Lyman Spitzer.

• April 26, 2006: Spitzer Space Telescope surpasses the 2.5 years of minimum expected lifetime.

• April 2009: Total depletion of liquid-helium coolant tank, end of cryogenic phase of the mission.

• May 2009: Development of a "warm", post-cryo program for the observation of extrasolar planets, search for brown dwarfs and wide area surveys of galaxies.

• December 2014: Expected telecommunications performance degradation and end of operations.

updated 2012-05-12 19:53:54

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