The site for humanity’s first-ever attempt to land a spacecraft on a comet has been chosen.
Philae, the tiny lander being carried by the Rosetta probe, will attempt on Nov. 12 to anchor itself to an area on the smaller of comet 67P/Churyumov-Gerasimenko. The location is known as Site J.
“Now that we know where we are definitely aiming for, we are an important step closer to carrying out this exciting – but high-risk – operation,” Fred Jansen, ESA’s Rosetta mission manager, said in a statement released Oct. 15.
Rosetta itself is now about 10 kilometers away from the comet. It will launch Philae, if all goes according to plan, when it is about 22.5 kilometers from the comet’s center.
Philae’s journey to the comet will take about seven hours. Communication confirming a successful landing on the comet can be expected to arrive at Earth during the early- to mid-morning hours in North America.
Rosetta’s mission team will confirm that the probe is on the correct trajectory and that Philae is ready to receive computer commands before the final authorization to send the tiny lander to comet 67P/Churyumov-Gerasimenko is transmitted.
Philae will not be idle during its movement from Rosetta to the comet. It will study the comet’s dust, gas, and plasma while moving slowly through the short distance in space.
Mission planners are not sure how much time Philae will have, once anchored on the comet, to study its nucleus and other features. The lander has a solar-powered battery, which will provide more or less energy depending on the degree to which the solar power receiver is covered by dust from the comet.
ESA said in a press release that Philae is not expected to be able to conduct scientific observations of the comet past March 2015.
Residents of the western states and New England may face a relatively mild winter this year, according to a new prediction by the National Oceanic & Atmospheric Administration.
The agency’s U.S. Winter Outlook, released today, indicates that the coastal and inter-mountain west will likely experience average winter temperatures that are above normal.
“The temperature outlook for November-December-January (NDJ) 2014-15 indicates elevated probabilities of above-normal mean temperatures for Alaska, the far west, along the northern tier of the continental U.S. eastward to include parts of the northeast and mid-Atlantic,” the document said. “Below-normal mean temperatures are most likely over areas from eastern New Mexico to the western Gulf coast states.”
Warmer does not mean drier, though. NOAA said that higher-than-average precipitation can be expected in southern California, the desert southwest, the southern Great Plains, across the deep south, and up the Atlantic coast to southern New England.
That may be good news for water-starved California, though the drought there is not likely to end.
“While we’re predicting at least a two-in-three chance that winter precipitation will be near or above normal throughout the state, with such widespread, extreme deficits, recovery will be slow,” Mike Halpert, acting director of NOAA’s Climate Prediction Center, said.
An El Nino event could well happen this winter, but if it does, it is expected to be a weak one. NOAA estimated on Oct. 9 that there is a 67 percent chance of an El Nino event in the coming months.
NASA has chosen three possible small objects in the region of space beyond Neptune that could serve as destinations for the New Horizons probe after it visits the dwarf planet Pluto.
The agency used the Hubble Space Telescope to select three Kuiper Belt objects, each only a tiny fraction the size of Pluto and ranging in size from 25-55 kilometers. All three KBOs are about one billion miles beyond Pluto.
New Horizons will visit the Pluto system next summer. After doing so, the spacecraft will continue to travel deeper into the farthest reaches of the solar system, where objects have remained frozen since the formation of the planets and dwarf planets billions of years ago.
New Horizons was launched on Jan. 19, 2006. By the time it reaches the three potential KBOs found by the Hubble Space Telescope, it will have traveled about four billion miles from the sun.