NASA will reveal new discoveries about the violent fate of our Milky Way galaxy on Thursday (May 31), the space agency has announced.
NASA will hold a press conference at 1 p.m. EDT (1700 GMT) Thursday at the agency's headquarters in Washington, D.C. Scientists will discuss new Hubble Space Telescope findings about the inevitable crash of the Milky Way and Andromeda galaxies, which will occur billions of years from now.
"Because of uncertainties in Andromeda's motion, it has not been possible to determine whether the Milky Way will have a head-on collision or glancing blow with the neighboring galaxy billions of years in the future," NASA officials said in a media alert Friday (May 25). "Hubble's precise observations will settle this question."
Why would Venus appear oval? Venus has been seen countless times from the surface of the Earth, and every time the Earth's atmosphere has dispersed its light to some degree. When the air has just the right amount of dust or water droplets, small but distant objects like Venus appear spread out into an angularly large aureole. Aureoles are not unusual to see and are frequently noted as circular coronas around the Sun or Moon. Recently, however, aureoles have been imaged that are not circular but distinctly oval. The oval Venusian aureole on the left was imaged by the astrophotographer who first noted the unusual phenomenon three years ago. Initially disputed, the unusual distortion has now been confirmed multiple times by several different astrophotographers. What causes the ellipticity is currently unknown.
Discovered on March 23rd 2012 by the Mount Lemmon survey in Arizona, Comet Lemmon is on an elliptical orbit with a period of almost 11,000 years. This is its first visit to the inner solar system in a very long time. The comet is brightening as it approaches the sun; light curves suggest that it will reach 2nd or 3rd magnitude, similar to the stars in the Big Dipper, in late March when it approaches the sun at about the same distance as Venus (0.7 AU).
At the moment, the comet is glowing like a 7th magnitude star, just below the limit of naked-eye visibility. To capture the faint details of the comet's filamentary tail, Olsen used a 10-inch telescope, a sensitive CCD camera, and an exposure time of 1 hour 17 minutes. Complete photo details are given here.
A NASA spacecraft studying the sun has recorded amazing video of a giant plume of super-hot plasma erupting from the star's surface, only to crash back down hours later.
The solar plasma eruption, which NASA scientists nicknamed a "Dragon Tail," rose up from the sun's surface today (Jan. 31) and was spotted by the agency's Solar Dynamics Observatory, a powerful spacecraft that constantly records the sun's weather in different wavelengths of light.
A video of the Dragon Tail solar eruption shows a tendril of solar plasma, which scientists call a "filament," extending across the northeastern face of the sun over the course of four hours. Near the end of the event, the filament begins to break apart.
Asteroid to Give Earth Record-Setting Close Shave on Feb 15
An asteroid half the size of a football field will give Earth the ultimate close shave this month, passing closer than many satellites when it whizzes by, but it won't hit the planet, NASA scientists say.
The asteroid 2012 DA14 will fly by Earth on Feb. 15 and zip within 17,200 miles (27, 680 kilometers) of the planet during the cosmic close encounter. The asteroid will approach much closer to Earth than the moon, and well inside the paths of navigation and communications satellites.
"This is a record-setting close approach," Don Yeomans, the head of NASA's asteroid-tracking program, said in a statement. "Since regular sky surveys began in the 1990s, we've never seen an object this big get so close to Earth."
Asteroid 2012 DA14 was discovered last year by an amateur team of stargazers at the La Sagra Sky Survey observatory in Spain. Yeomans stressed that, while the asteroid's approach bring it closer than the geosynchronous satellites orbiting 22,245 miles (35,800 km) above Earth, 2012 DA14 poses no threat of a deadly collision with the planet.
"2012 DA14 will definitely not hit Earth. The orbit of the asteroid is known well enough to rule out an impact," Yeomans, who heads the Near-Earth Object Program at NASA's Jet Propulsion Laboratory in Pasadena, Calif. He added that the odds it will slam into a satellite are "extremely remote." -Source
Partial Lunar Eclipse Next Week
The first lunar eclipse of the year will occur next week when the full moon passes behind Earth, casting a shadow over a large expanse of the lunar surface.
On June 4, a partial lunar eclipse will be visible to skywatchers in North America, South America, Australia, eastern regions of Asia and across the Pacific Ocean, weather permitting.
Lunar eclipses occur when the moon orbits behind Earth with respect to the sun, and the planet's shadow blocks light from the sun that would otherwise hit the moon. Since only a fraction of the moon will covered in shadow next week, astronomers call this type of eclipse a partial lunar eclipse.
For skywatchers in the eastern United States, the eclipse begins before dawn as the moon is setting in the west. The moon will move behind the planet at roughly 6 a.m. EDT (3 a.m. PDT; 1000 GMT). About 37 percent of the moon's surface will be darkened at maximum eclipse, which will take place at approximately 7:04 a.m. EDT (4:04 a.m. PDT; 1104 GMT), according to NASA astronomers. -Source
