This Week at NASA | Transit of Mercury; Kepler Sees 1,284 New Planets; more
The planet Mercury’s transit of the sun on May 9 provided an opportunity for sky-watchers throughout the U.S. to witness a rare celestial event that happens only about 13 times a century. Mercury’s transit, as it passed between Earth and the sun, made it appear as a small dark dot against the face of the sun. NASA’s coverage of the event included a televised roundtable of NASA science experts discussing the exceptional opportunity presented to learn more about the atmospheric makeup of our solar system’s smallest planet. Mercury’s next transit of the sun occurs in 2019. But, those of us in the U.S. have a big celestial event to look forward to even before that – a total solar eclipse, on August 21 of 2017. Also, Kepler Confirms More Than 1,200 New Planets, Dragon Leaves ISS with Science, Canadian Wildfires Seen from Space, Two Martian Years for Curiosity, and Vehicle Assembly Building Platforms.
The planet Mercury’s transit of the sun on May 9 provided an opportunity for sky-watchers throughout the U.S. to witness a rare celestial event that happens only about 13 times a century. Mercury’s transit, as it passed between Earth and the sun, made it appear as a small dark dot against the face of the sun. NASA’s coverage of the event included a televised roundtable of NASA science experts discussing the exceptional opportunity presented to learn more about the atmospheric makeup of our solar system’s smallest planet.
Jim Green, NASA Director of Planetary Science:
Mercury’s next transit of the sun occurs in 2019. But, those of us in the U.S. have a big celestial event to look forward to even before that – a total solar eclipse, on August 21 of 2017.
NASA’s Kepler mission has verified 1,284 new planets outside our solar system – the single largest finding of planets to date. The new confirmed planets come from a collection of potential planets identified by the Kepler space telescope’s July 2015 planet catalog. Scientists say nine of the newly-validated planets could be rocky, like Earth, and orbit in their sun’s habitable zone, which is the distance from a star where orbiting planets can have surface temperatures that allow liquid water to pool. Of the almost 5,000 total planet candidates found to date, more than 3,200 now have been verified, and 2,325 of those were discovered by Kepler.
A month after delivering almost 7,000 pounds of science and cargo, including the Bigelow Expandable Activity Module (BEAM), to the International Space Station, the SpaceX Dragon cargo spacecraft returned to Earth on May 11. Dragon brought back about 3,600 pounds of cargo, experiments and biomedical samples from the recently completed year-long mission of former NASA astronaut Scott Kelly and Mikhail Kornienko of Roscosmos.
Several satellites operated, or jointly operated by NASA continue to capture images from space of the massive Fort McMurray wildfire burning in Canada’s Alberta province. Images from May 8 taken by Earth observing spacecraft, including the Terra, Suomi NPP and Aqua satellites, showed smoke from the catastrophic event wafting east – all the way to the Atlantic Ocean.
For all of us on Earth it has been almost four years since the August 5, 2012 Pacific Time landing on Mars of NASA’s Curiosity rover. But, based on “local time” at Mars on May 11, Curiosity completed only its second Martian year on the Red Planet. Since Mars is farther from the sun, it takes about 687 Earth days to circle our solar system’s star and complete a Martian year. In its time on Mars, the rover has recorded environmental patterns through two full cycles of Martian seasons. The data compiled by Curiosity can help scientists distinguish seasonal patterns on Mars from otherwise sporadic environmental events.
NASA’s Ground Systems Development and Operations Program continues its work to retrofit NASA’s Kennedy Space Center’s Vehicle Assembly Building (VAB) with new platforms for processing of the Space Launch System rocket and Orion spacecraft, prior to their first test flight in 2018. Several platforms have been installed in the facility, powered on and tested. Once the work is completed, there will be 10 levels of platforms in the cavernous VAB to provide workers with access to the rocket and spacecraft.
And that’s what’s up this week @NASA.
NASA’s Kepler Mission Announces Largest Collection of Planets Ever Discovered
NASA’s Kepler mission has verified 1,284 new planets – the single largest finding of planets to date.
“This announcement more than doubles the number of confirmed planets from Kepler,” said Ellen Stofan, chief scientist at NASA Headquarters in Washington. “This gives us hope that somewhere out there, around a star much like ours, we can eventually discover another Earth.”
Analysis was performed on the Kepler space telescope’s July 2015 planet candidate catalog, which identified 4,302 potential planets. For 1,284 of the candidates, the probability of being a planet is greater than 99 percent – the minimum required to earn the status of “planet.” An additional 1,327 candidates are more likely than not to be actual planets, but they do not meet the 99 percent threshold and will require additional study. The remaining 707 are more likely to be some other astrophysical phenomena. This analysis also validated 984 candidates previously verified by other techniques.
“Before the Kepler space telescope launched, we did not know whether exoplanets were rare or common in the galaxy. Thanks to Kepler and the research community, we now know there could be more planets than stars,” said Paul Hertz, Astrophysics Division director at NASA Headquarters. “This knowledge informs the future missions that are needed to take us ever-closer to finding out whether we are alone in the universe.”
Kepler captures the discrete signals of distant planets – decreases in brightness that occur when planets pass in front of, or transit, their stars – much like the May 9 Mercury transit of our sun. Since the discovery of the first planets outside our solar system more than two decades ago, researchers have resorted to a laborious, one-by-one process of verifying suspected planets.
This latest announcement, however, is based on a statistical analysis method that can be applied to many planet candidates simultaneously. Timothy Morton, associate research scholar at Princeton University in New Jersey and lead author of the scientific paper published in The Astrophysical Journal, employed a technique to assign each Kepler candidate a planet-hood probability percentage – the first such automated computation on this scale, as previous statistical techniques focused only on sub-groups within the greater list of planet candidates identified by Kepler.
“Planet candidates can be thought of like bread crumbs,” said Morton. “If you drop a few large crumbs on the floor, you can pick them up one by one. But, if you spill a whole bag of tiny crumbs, you’re going to need a broom. This statistical analysis is our broom.”
In the newly-validated batch of planets, nearly 550 could be rocky planets like Earth, based on their size. Nine of these orbit in their sun’s habitable zone, which is the distance from a star where orbiting planets can have surface temperatures that allow liquid water to pool. With the addition of these nine, 21 exoplanets now are known to be members of this exclusive group.
“They say not to count our chickens before they’re hatched, but that’s exactly what these results allow us to do based on probabilities that each egg (candidate) will hatch into a chick (bona fide planet),” said Natalie Batalha, co-author of the paper and the Kepler mission scientist at NASA’s Ames Research Center in Moffett Field, California. “This work will help Kepler reach its full potential by yielding a deeper understanding of the number of stars that harbor potentially habitable, Earth-size planets — a number that’s needed to design future missions to search for habitable environments and living worlds.”
Of the nearly 5,000 total planet candidates found to date, more than 3,200 now have been verified, and 2,325 of these were discovered by Kepler. Launched in March 2009, Kepler is the first NASA mission to find potentially habitable Earth-size planets. For four years, Kepler monitored 150,000 stars in a single patch of sky, measuring the tiny, telltale dip in the brightness of a star that can be produced by a transiting planet. In 2018, NASA’sTransiting Exoplanet Survey Satellite will use the same method to monitor 200,000 bright nearby stars and search for planets, focusing on Earth and Super-Earth-sized.
Ames manages the Kepler missions for NASA’s Science Mission Directorate in Washington. The agency’s Jet Propulsion Laboratory in Pasadena, California, managed Kepler mission development. Ball Aerospace & Technologies Corporation operates the flight system, with support from the Laboratory for Atmospheric and Space Physics at the University of Colorado in Boulder.
For more information about the Kepler mission, visit: http://www.nasa.gov/kepler(c)2016 NASA | SCVTV