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On the night Neptune forms a straight line with the Sun and Earth in the Solar System, Asteroid 2002 CU11, with an approximate size of AT&T Stadium (500 m ­ 1.3 km), will flyby Earth on its closest approach. The asteroid, which we nicknamed “Dodgeball” because of its frequent returns to Earth’s vicinity, was originally listed on the Sentry Risk Table with a Torino Scale rating of 1 ­ at which time the asteroid was calculated to have a 1 in 9,300 chance of impacting Earth in 2049. However, follow­up observations and refinements of the asteroid’s orbit have removed such impact fears. The asteroid has an unusual, highly inclined orbit, about 48 degrees above the plane of the Solar System.

Slooh will celebrate mankind’s scientific prowess, and good fortune, with live views of this dodgy neighborhood asteroid as it zips past our world, featuring as well live views of Neptune and its giant moon Triton performing a “Moonwalk” style backward dance.

Neptune coverage will begin on Friday, August 29th starting at 5 PM PDT / 8 PM EDT / 00:00 UTC (8/30) ­ International Times: goo.gl/bLWshU with live views from the Institute of Astrophysics, Canary Islands (IAC). The four hour image stream will be accompanied by a multitude of audio segments on Neptune from different Slooh personalities, including Slooh Astronomer Bob Berman.

Slooh will transition coverage to Asteroid 2002 CU11 starting at 9 PM PDT / 12 AM EDT (8/30) / 04:00 UTC (8/30) ­ International Times: goo.gl/qCXhsT with live views again from the Institute of Astrophysics, Canary Islands (IAC). Slooh will track Asteroid 2002 CU11 live on its closest approach to Earth. The live image stream will be hosted by Geoff Fox, accompanied by expert commentary from Slooh Astronomer, Bob Berman, Slooh engineer, Paul Cox, and special guest, Lindley N. Johnson, NEO Programs Executive, Planetary Science Division, NASA HQ. Viewers can ask questions during the show by using hashtag #CU11Neptune.

On August 29th the farthest planet, Neptune, will line up directly opposite the Sun as seen from Earth. This alignment, called opposition, provides the ideal occasion to explore the many

oddities of this distant planet, discovered in 1846. Neptune is the eighth planet from our Sun, the fourth largest planet by diameter, and is 17 times the mass of the Earth. Neptune has 14 known moons with the final one discovered just last year. Its largest moon Triton is 1,680 miles (2,700 km) across. In comparison, the diameter of our Moon is 2159 miles (3,474 km).

Discovered in February 2002 by the Lincoln Near­Earth Asteroid Research (LINEAR), Asteroid CU11 orbits the Sun in 492 days, and will pass within 13.5 lunar distances (about 3.2 million miles distance) this time around. In August of 2080, Asteroid 2002 CU11 will flyby Earth at less than two lunar distances. Based on 2002 CU11’s size and speed, it’s estimated that if it should ever impact it would release the energy of 53,000 megatons of TNT. From observations made during the show, Slooh will pass along valuable orbital data to help the Minor Planet Center to further improve the asteroid’s orbital information.

To see Neptune during opposition, astronomy hobbyists should point their telescope towards the constellation of Aquarius, just to the left of the 4th magnitude star Sigma Aquarii, and look for a blue 8th magnitude “star.” It will be highest up between 10 PM and 2 AM, local time.

“Neptune shares with Earth a distinct blue color,” says Slooh astronomer Bob Berman. “In our case the color comes from a combo­plate: Our oceans absorb red light and reflect away the blue, plus our atmosphere scatters blue light. But Neptune’s color is due to methane ­­ what we on Earth call natural gas. It absorbs the sun’s red light, but bounces the blue back to our eyes. The result is arguably the most deeply colored planet in the solar system. And the only one that always requires a telescope, since Neptune alone is never visible to the naked eye.”