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Jolly Roger

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Event	                                              UTC Time	                        Time in New York*
First location to see the partial transit begin	      May 9 at 11:10:25	                May 9 at 7:10:25 AM
Geocentric** partial transit begins (exterior contact)May 9 at 11:12:18	                May 9 at 7:12:18 AM
First location to see the full transit begin	      May 9 at 11:13:37	                May 9 at 7:13:37 AM
Geocentric** full transit begins (interior contact)   May 9 at 11:15:30	                May 9 at 7:15:30 AM
Mercury is closest to the Sun's center	              May 9 at 14:57:25	                May 9 at 10:57:25 AM
Geocentric** full transit ends (interior contact)     May 9 at 18:39:12	                May 9 at 2:39:12 PM
Last location to see full transit end	              May 9 at 18:41:05	                May 9 at 2:41:05 PM
Geocentric** transit ends (exterior contact)	      May 9 at 18:42:24	                May 9 at 2:42:24 PM
Last location to see partial transit end	      May 9 at 18:44:17	                May 9 at 2:44:17 PM

path-760.png

 

 

Jos od 13 novembra 1986, kada je poslednji put bilo moguce pratiti prelaz Merkura preko diska Sunca, cekam na ovu priliku. 1993, 1999, 2003 i 2006, kada su se prolazi dogadjali, Sunce je bilo ispod horizonta. A ni 1986. nisam mogao da posmatram prolaz, prvi teleskop sam kupio juna 1990. Dakle, dugo cekanje je privedeno kraju, pa ja pod misku mogu da stavim da sam pored oba Venerina prolaza (2004. iz Juzne Afrike i 2012. pored Hadsona), konacno arhivirao i prolaz Merkura. Ostaje mi i sam Merkur da posmatram, on je jedina planeta Suncevog sistema kojeg jos uvek nisam direktno posmatrao (nisam ni Pluton, ali on em ne moze direktno, em je mucenik demotovan), zahvaljujuci i geometriji Suncevog sistema, ali i mestima zivljenja (MZ Brdjani govore sami za sebe, a NYC opet za sebe). Valjda necu proci ko Kopernik...

 

edit: samo da dodam da su uslovi posmatranja uzasni. atmosferske turbulencije otezavaju posmatranje, a ni "velicina" merkurove senke ne pripomaze pri posmatranju, jednostavno se ne razlikuje od neke najobicnije sunceve pege. srecom, danas je vidljiva samo jedna grupa suncevih pega severno od merkrove senke, dok je sama senka usamljena ispod suncevog ekvatora.

Edited by Њујоркер
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May 10, 2016

RELEASE 16-051

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’s Transiting 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.

 


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  • 1 month later...

Juno noćas (tj. oko 8 ujutru po našem vremenu), posle skoro pet godina puta, uleće u klinč sa Jupiterovom gravitacijom. Ako su majstori sve dobro izračunali, 35-to minutni engine burn treba da uspori sondu i da je ubaci u orbitu oko Jupitera. Ako su se negde zajebali, ili nešto ne odšljaka kako treba, ode milijarda i kusur dolara ili dalje kroz Sunčev sistem, ili u Jupiter.

 

Sve sekvence su preprogramirane, a obzirom da je Jupiter 48 svetlosnih minuta daleko, mogu samo da sede na ivici stolica i da čekaju potrvrdu signala da je sve prošlo kako treba.

 

Ukoliko sve prođe kako valja (fingers crossed), izgruvaće 37 orbitalnih obilazaka, svaki traje 14 dana.

 

Juno_trajectory_through_radiation_belts.

 

Good luck Juno!

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  • 2 weeks later...

U.S. and Russian Scientists Are Making Plans to Go Back to the Moon Together
Is there a moon base in U.S. and Russia's future?

 

1468955755-1468866738-02-mpp-rkk-phase1.

 

American and Russian engineers are getting closer to a new plan for cooperating in space, one that would go beyond low Earth orbit and preserve the multinational alliance forged at the dawn of the International Space Station program in 1993. Organizations on both sides are quietly toying with the idea of going back to the moon together. That is, if politics don't get in the way.

With the ISS scheduled to make a controlled plunge into the ocean in 2024, the partners have been preparing to go their own ways. NASA, while funding companies like SpaceX to go to orbit, is developing the Orion spacecraft and the super-heavy rocket called Space Launch System (SLS) for manned missions into deep space and potentially as far as Mars. The European Space Agency (ESA) jumped on NASA's bandwagon few years ago, agreeing to contribute the service and propulsion module for the Orion. But the second-largest ISS contributor, Russia, has so far remained uncommitted to any joint venture beyond the station.

 

1468955513-syn-toc-1468866907-assets-inf

 

A recent economic crisis in Russia has put a dumper on the nation's space activities. But a bigger problem for cooperation in space may be the souring relationship between Moscow and Washington back on Earth. While NASA and the Russian space agency Roskosmos try to navigate the political minefield, industry engineers on both sides formed their own alliances to look into the matter from the technical prospective. American aerospace companies such as Boeing and Lockheed Martin, as well as Russia's key manned space contractors RKK Energia and GKNPTs Khrunichev, pitched in on a new plan to work together. Several mission strategies have recently surfaced that focus on a multinational habitat in the vicinity of the Moon, known as cislunar space. It could serve as a platform for the exploration of our natural satellite and a springboard for missions to asteroids and even to Mars. The two sides seem to understand why they need each other, and how the pieces fit together. For their part, the Russians have mastered the development and operation of space modules that can house crews and provide propulsion for years at a time. Turns out, that's exactly what the U.S. could use. Such a habitat would expand the livable volume for the Orion crews beyond the cramped one-room compartment of the ship's command module, extending the possibilities for missions. In consultations with their American colleagues, Russians offered a selection of off-the-shelf or soon-to-be-available hardware for constructing the joint deep-space habitat. For example, a small docking compartment built by RKK Energia for the ISS could be easily replicated and converted into a 10-ton add-on for the hypothetical near-lunar habitat, with its own life-support system, sleeping quarters and cargo space. Each piece of an ever-growing base could be launched over a period of several years as cargo that piggybacks on SLS rocket launches. Russian engineers drafted a mini-train of such modules, which would be lined up one by one behind an unmanned space locomotive, providing propulsion and 150 kilowatts of electric power. Alternatively, Russia could supply an all-in-one module for the new base that would have power, propulsion, and large living quarters for the crew. It is based on the most advanced Russian module, which is being developed as a potential cornerstone of the future Russian space station in the Earth's orbit. The drawback? A nearly 24-ton spacecraft will require a dedicated SLS rocket to boost it toward the Moon, leaving no room for the Orion or its crew on that launch.

 

Russia would get plenty out of the deal, too. Without American cooperation, has no chance of getting a rocket comparable to SLS until 2030, even under the best circumstances. Just to get to the moon, Russia devised a cumbersome scheme involving four launches of the yet-to-be-built Angara-5V rockets. If SLS works as planned, then the Americans could provide Roskosmos an easy ride to the vicinity of the Moon a decade earlier.

Why build a new base near the moon? Joint US-Russian teams could use remote control to drive robotic geology rovers on the surface of the Moon. The habitat could be used to study an asteroid brought into the vicinity of the Moon. Potentially, a piloted lander could be added to the mix, opening door to the human lunar landing. According to one proposal, astronauts and cosmonauts together could attempt a nearly 400-day mission on the surface of the Moon in the late 2020s to simulate a Martian expedition.

Yet these are only big ideas for now. The newest proposals for American and Russian cooperation were just presented at an ISS research and development conference in San Diego last week (July 12-14). Exactly where the base would go an who would take what responsibility is still up for grabs. In the aftermath of the event, William Gerstenmaier, NASA's Associate Administrator for Human Exploration and Operations, told Popular Mechanics that the agency welcomes the industry efforts, but warned that they had not been commissioned or endorsed at NASA.

"Until we look at them, I can't pass judgment whether they are viable or not," Gerstenmaier said. But, "it is encouraging that the industry is doing it on its own… and it is consistent with what we are thinking about, including going to cis-lunar space. … So when we, the government, decide something to do, the industry has (already) done its homework." Gerstenmaier also emphasized the potential provided by near-lunar missions for venturing much further into space, rather than exploring the Moon itself: "Don't think of it as a space station around the Moon. Think of it as the beginning of the Mars transit system."

When beefed up to a right level of power, life-support and propulsion, the international vehicle could leave the lunar vicinity and head to asteroids or Mars. "These modules are fairly versatile: you put power, you put right thermal system on them and you can use them in a wide variety of applications," Gerstenmaier explained. (According to the current US policy, NASA sees no need to return to the surface of the Moon, however the agency is open to cooperation if its partners, such as Roskosmos or ESA, take a lead in the lunar landing.)

 

1468955516-syn-toc-1468866971-03-sls.jpg

 

NASA will have to make a decision on the possible architecture and design of the future deep-space habitat within a year or two, in order to build all the necessary hardware by the time the Orion spacecraft comes out of flight testing in the first half of the 2020s.

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