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Meet Rosie – Boeing’s First Anthropometric Starliner Commander
Rosie-in-Spacecraft-1024x576.jpg
Onboard Boeing’s CST-100 Starliner is an anthropometric test device, called Rosie, who will provide a wealth of information about what astronauts will experience during flight aboard the spacecraft. Boeing named the test device after Rosie the Riveter, an icon who inspired women to join aerospace. Rosie’s 15 sensors will collect valuable data during the mission that will help make future crewed missions safe on Starliner.
Boeing-OFT-Rosie-and-Snoopy-300x169.jpg
Everyone’s favorite –Snoopy – is making his return to space aboard the Starliner spacecraft.
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Jupiter Probably Has 600 Small, Irregular Moons
Изображение
The better our technologies get, the better we get at finding objects in space. That’s certainly true of Jupiter and its moons. Prior to Galileo, nobody knew the other planets had moons. Then in 1609/10, as he made improvements to his telescope, he aimed it at the gas giant and eventually found four moons: Io, Europa, Ganymede, and Callisto. Now those four natural satellites also bear his name: the Galilean moons.

Over the centuries since then, and especially in our digital age, astronomical tools and methods kept improving. In particular, wide-field CCD (Charge Coupled Devices) have led to an explosion of astronomical discoveries. In recent years, the confirmed number of Jovian moons has risen to 79. Now, a new study says that there may be 600 small irregular moons orbiting Jupiter.

The title of the new study is “The population of km-scale retrograde jovian irregular moons.” The lead author is Edward Ashton from the Department of Physics and Astronomy at the University of British Columbia. The authors will present their findings at the virtual Europlanet Science Congress 2020.

To be clear, the team of astronomers did not actually see 600 moons. Instead, they pored over archival 2010 data from the Canada-France-Hawaii Telescope. They searched a small area of the sky in that data—about one square degree—and found four dozen small, irregular moons. Based on that, they extrapolated the number of small moons that should be orbiting Jupiter, arriving at the 600 number.

There are two categories of moons: regular and irregular. While regular moons form by accretion of material in a disk, the same way planets do, irregulars are captured objects. In this study, the team of researchers found an abundance of small irregular moons, objects captured by Jupiter’s powerful gravity.
Изображение
This annotated color view of Jupiter and its four largest moons — Io, Europa, Ganymede and Callisto — was taken by the JunoCam camera on NASA’s Juno spacecraft on June 21, 2016, at a distance of 6.8 million miles (10.9 million kilometers) from Jupiter. Image credit: NASA/JPL-Caltech/MSSS
In 2017, researchers published a study announcing the discovery of 12 more irregular moons orbiting Jupiter. Prior to this new research, the number of known Jovian irregulars was 71. And scientists have speculated for years that Jupiter has an undiscovered population of smaller moons. Some astronomers have said that the large giants all have the same number of satellites, despite differences in their masses. It’s just that they’re hard to see.

The Canada-France-Hawai‘i Telescope on Mauna Kea played a central role in this work. That telescope has a powerful digital camera called the MegaCam. It’s a 340 megapixel wide-field imager that sees in the optical and the near-infrared. In this study, the astronomers focused on 60 exposures of 140 seconds each of a region near Jupiter.

Their method involved what the team calls a “shift-and-stack parameter space for the data set.” That method can reveal smaller, fainter moons hidden in the data. Basically, there are 126 ways to combine these images, by digitally shifting and stacking them, to mimic all the possible speeds and directions that these new, potential Jovian moons might travel across the sky.

The team of astronomers found 52 objects in their images which they identified as irregular moons. The objects had magnitudes down to 25.7, and that corresponds to objects with diameters of approximately 800 meters (875 yards.) Of those 52, seven of the brightest were already-known irregular moons. While those seven are prograde moons, the other 45 are very likely retrograde moons, meaning they orbit opposite of Jupiter’s direction of rotation.

From that data, the team extrapolated to arrive at their total of 600 irregular Jovian moons.
Изображение
Jupiter’s inner moons are prograde, while the outter moons tend to be retrograde. The oddball moon Valetudo, discovered in 2017, is a prograde moon that crosses the orbit of the outer group of retrograde moons. Image Credit: Roberto Molar-Candanosa / Carnegie Institution for Science.
These are not confirmed discoveries, yet. Confirmation requires observation with large, ground-based telescopes. Considering the small sizes, and the time it takes to for each moon to complete an orbit, that’s a huge task. There may not be enough scientific value in confirming all these tiny objects to justify all of that sought-after observing time.

In an interview with Sky and Telescope, lead author Edward Ashton said there are no plans for follow-up observations to confirm these findings. “It would be nice to confirm them,” Ashton said, “but there is no way to track them without starting from scratch.”

Unlike Jupiter’s larger moons, like Io, Europa and Ganymede, these irregular moons did not form by accreting material in a disk. Instead, they likely formed as stand-alone Solar System objects in heliocentric orbits. Through some uncertain mechanism, they were eventually captured into their orbits around Jupiter. Their capture may have been due to “gas drag, pull down due to sudden mass growth and threebody interactions,” the authors write in their paper.

This study also raises an interesting question: What, exactly, is a moon?
Изображение
We grow up looking at the Earth’s moon, so we tend to think we know what a “moon” is. But there’s no strict definition of the size range for moons. Image Credit: NASA / GSFC / Arizona State University
At what point is an object small enough to no longer be considered a moon? There are bound to be all kinds of boulders, rocks, and dust orbiting planets. Some small satellites are referred to as moonlets, but there’s no agreed upon definition of that, either. Is something that’s only 100 meters (328 ft.) in diameter really a moon? A moonlet? Is there a cutoff?

The International Astronomical Union doesn’t name objects smaller than one km (0.62 mi) in diameter, so none of these objects will get recognizable names. And their confirmation will have to wait for some future day. It’s possible that the Vera Rubin Observatory, which will have the power to detect dim, transient objects in the Solar System, can confirm the existence of these moons, and more.

These results are an interesting new chapter in our understanding of Jupiter. We’ve gone from Galileo’s 1610 observation of four moons orbiting the planet, to this new study, involving powerful telescopes with advanced digital cameras, and complex computer-based methods of examining the data.

Now, we know that Jupiter’s moons include the largest natural satellite in the Solar System (Ganymede), a volcanic moon (Io), and moons with oceans under a layer of ice (Europa.) We’re even sending a spacecraft, NASA’s Europa Clipper, just to study one of Jupiter’s moons more closely, seeking signs of life.
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Ten Things to Know About Bennu
NASA’s first mission to return a sample from an ancient asteroid arrived at its target, the asteroid Bennu, on Dec. 3, 2018. This mission, the Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer, or OSIRIS-REx, is a seven-year long voyage set to conclude upon the delivery to Earth of at least 2.1 ounces (60 grams) and possibly up to almost four and a half pounds (two kilograms) of sample. It promises to be the largest amount of extraterrestrial material brought back from space since the Apollo era. The 20-year anniversary of the asteroid’s discovery was in September 2019 — and scientists have been collecting data ever since. Here’s what we already know (and some of what we hope to find out) about this pristine remnant from the early days of our solar system.


1. IT’S VERY, VERY DARK...
Bennu is classified as a B-type asteroid, which means it contains a lot of carbon in and along with its various minerals. Bennu’s carbon content creates a surface on the asteroid that reflects about four percent of the light that hits it — and that’s not a lot. For contrast, the solar system’s brightest planet, Venus, reflects around 65 percent of incoming sunlight, and Earth reflects about 30 percent. Bennu is a carbonaceous asteroid that hasn’t undergone drastic, composition-altering change, meaning that on and below its deeper-than-pitch-black surface are chemicals and rocks from the birth of the solar system.
Изображение

2. ...AND VERY, VERY OLD.
Bennu has been (mostly) undisturbed for billions of years. Not only is it conveniently close and carbonaceous, it is also so primitive that scientists calculated it formed in the first 10 million years of our solar system’s history — over 4.5 billion years ago. Thanks to the Yarkovsky effect -- the slight push created when the asteroid absorbs sunlight and re-emits that energy as heat -- and gravitational tugs from other celestial bodies, it has drifted closer and closer to Earth from its likely birthplace: the Main Asteroid Belt between Mars and Jupiter.

3. BENNU IS A “RUBBLE-PILE” ASTEROID — BUT DON’T LET THE NAME TRICK YOU.
Is Bennu space trash or scientific treasure? While “rubble pile” sounds like an insult, it’s actually a real astronomy classification. Rubble-pile asteroids like Bennu are celestial bodies made from lots of pieces of rocky debris that gravity compressed together. This kind of detritus is produced when an impact shatters a much larger body (for Bennu, it was a parent asteroid around 60 miles [about 100 km] wide). Bennu, for contrast, is about as tall as the Empire State Building. It likely took just a few weeks for these shards of space wreckage to coalesce into the rubble-pile that is Bennu. Bennu is full of holes inside, with 20 to 40 percent of its volume being empty space. The asteroid is actually in danger of flying apart, if it starts to rotate much faster or interacts too closely with a planetary body.

4. ASTEROIDS MAY HARBOR HINTS ABOUT THE ORIGIN OF ALL LIFE ON EARTH...
Bennu is a primordial artifact preserved in the vacuum of space, orbiting among planets and moons and asteroids and comets. Because it is so old, Bennu could be made of material containing molecules that were present when life first formed on Earth. All Earth life forms are based on chains of carbon atoms bonded with oxygen, hydrogen, nitrogen and other elements. However, organic material like the kind scientists hope to find in a sample from Bennu doesn’t necessarily always come from biology. It would, though, further scientists’ search to uncover the role asteroids rich in organics played in catalyzing life on Earth.

5. ...BUT ALSO PLATINUM AND GOLD!
Extraterrestrial jewelry sounds great, and Bennu is likely to be rich in platinum and gold compared to the average crust on Earth. Although most aren’t made almost entirely of solid metal (but asteroid 16 Psyche may be!), many asteroids do contain elements that could be used industrially in lieu of Earth’s finite resources. Closely studying this asteroid will give answers to questions about whether asteroid mining during deep-space exploration and travel is feasible. Although rare metals attract the most attention, water is likely to be the most important resource in Bennu. Water (two hydrogen atoms bound to an oxygen atom) can be used for drinking or separated into its components to get breathable air and rocket fuel. Given the high cost of transporting material into space, if astronauts can extract water from an asteroid for life support and fuel, the cosmic beyond is closer than ever to being human-accessible.

6. SUNLIGHT CAN CHANGE THE ASTEROID’S ENTIRE TRAJECTORY.
Gravity isn’t the only factor involved with Bennu’s destiny. The side of Bennu facing the Sun gets warmed by sunlight, but a day on Bennu lasts just 4 hours and 17.8 minutes, so the part of the surface that faces the Sun shifts constantly. As Bennu continues to rotate, it expels this heat, which gives the asteroid a tiny push towards the Sun by about 0.18 miles (approximately 0.29 kilometers) per year, changing its orbit.

7. THERE IS A SMALL CHANCE THAT BENNU WILL IMPACT EARTH LATE IN THE NEXT CENTURY.
The NASA-funded Lincoln Near-Earth Asteroid Research team discovered Bennu in 1999. NASA’s Planetary Defense Coordination Office continues to track near-Earth objects (NEOs), especially those like Bennu that will come within about 4.6 million miles (7.5 million kilometers) of Earth’s orbit and are classified as potentially hazardous objects. Between the years 2175 and 2199, the chance that Bennu will impact Earth is only 1-in-2,700, but scientists still don’t want to turn their backs on the asteroid. Bennu swoops through the solar system on a path that scientists have confidently predicted, but they will refine their predictions with the measurement of the Yarkovsky Effect by OSIRIS-REx and with future observations by astronomers.

8. SAMPLING BENNU WILL BE HARDER THAN WE THOUGHT.
Early Earth-based observations of the asteroid suggested it had a smooth surface with a regolith (the top layer of loose, unconsolidated material) composed of particles less than an inch (a couple of centimeters) large — at most. As the OSIRIS-REx spacecraft was able to take pictures with higher resolution, it became evident that sampling Bennu would be far more hazardous than what was previously believed: new imagery of Bennu’s surface show that it’s mostly covered in massive boulders, not small rocks. OSIRIS-REx was designed to be navigated within an area on Bennu of nearly 2,000 square yards (meters), roughly the size of a parking lot with 100 spaces. Now, it must maneuver to a safe spot on Bennu’s rocky surface within a constraint of less than 100 square yards, an area of about five parking spaces.

Изображение
Captured on Aug. 11, 2020 during the second rehearsal of the OSIRIS-REx mission’s sample collection event, this series of images shows the SamCam imager’s field of view as the NASA spacecraft approaches asteroid Bennu’s surface. The rehearsal brought the spacecraft through the first three maneuvers of the sampling sequence to a point approximately 131 feet (40 meters) above the surface, after which the spacecraft performed a back-away burn.
Credits: NASA/Goddard/University of Arizona
Full story
9. BENNU WAS NAMED AFTER AN ANCIENT EGYPTIAN DEITY.
Bennu was named in 2013 by a nine-year-old boy from North Carolina who won the Name that Asteroid! competition, a collaboration between the mission, the Planetary Society, and the LINEAR asteroid survey that discovered Bennu. Michael Puzio won the contest by suggesting that the spacecraft’s Touch-and-Go Sample Mechanism (TAGSAM) arm and solar panels resemble the neck and wings in illustrations of Bennu, whom ancient Egyptians usually depicted as a gray heron. Bennu is the ancient Egyptian deity linked with the Sun, creation and rebirth — Puzio also noted that Bennu is the living symbol of Osiris. The myth of Bennu suits the asteroid itself, given that it is a primitive object that dates back to the creation of the Solar System. Themes of origins and rebirth are part of this asteroid’s story. Birds and bird-like creatures are also symbolic of rebirth, creation and origins in various ancient myths.

10. BENNU IS STILL SURPRISING US!
The spacecraft’s navigation camera observed that Bennu was spewing out streams of particles a couple of times each week. Bennu apparently is not only a rare active asteroid (only a handful of them have been as of yet identified), but possibly with Ceres explored by NASA’s Dawn mission, among the first of its kind that humanity has observed from a spacecraft. More recently, the mission team discovered that sunlight can crack rocks on Bennu, and that it has pieces of another asteroid scattered across its surface. More pieces will be added to Bennu’s cosmic puzzle as the mission progresses, and each brings the solar system’s evolutionary history into sharper and sharper focus.
Изображение
This view of asteroid Bennu ejecting particles from its surface on January 19, 2019 was created by combining two images taken on board NASA’s OSIRIS-REx spacecraft. Other image processing techniques were also applied, such as cropping and adjusting the brightness and contrast of each image.
Credits: NASA/Goddard/University of Arizona/Lockheed Martin
Full story
Goddard provides overall mission management, systems engineering, and the safety and mission assurance for OSIRIS-REx. Dante Lauretta of the University of Arizona, Tucson, is the principal investigator, and the University of Arizona also leads the science team and the mission’s science observation planning and data processing. Lockheed Martin Space in Denver built the spacecraft and is providing flight operations. Goddard and KinetX Aerospace are responsible for navigating the OSIRIS-REx spacecraft. OSIRIS-REx is the third mission in NASA’s New Frontiers Program, which is managed by NASA’s Marshall Space Flight Center in Huntsville, Alabama, for the agency’s Science Mission Directorate in Washington.

For more information about NASA's OSIRIS-REx mission, visit:

www.nasa.gov/osiris-rex
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Dragon Crew-1 capsule, with 4 astronauts aboard, on way to ISS
Drama-free countdown marks a major success for NASA and SpaceX
CAPE CANAVERAL, Fla. — SpaceX launched four astronauts to the International Space Station on Sunday in a spectacular evening liftoff that came days after the company’s Dragon capsule became the first privately owned and operated spacecraft to be certified by NASA for human spaceflight.

SpaceX earned that designation and the right to undertake what NASA hopes will be regular missions to the space station and back after it completed a test flight of two astronauts earlier this year. That May launch was the first of NASA astronauts from U.S. soil since the space shuttle was retired in 2011, forcing the United States to rely on Russia for flights to orbit for nearly a decade.

With Sunday’s launch, NASA took another step toward a new era in human spaceflight in which private companies partner with the government to build and design spacecraft and rockets. And it marked a coming-of-age moment for SpaceX, the California company founded by Elon Musk that was once viewed as a maverick start-up but is now one of the space industry’s stalwarts and one of NASA’s most significant partners.

SpaceX’s Falcon 9 rocket ignited its nine engines and lifted off at 7:27 p.m. Eastern time from launchpad 39A, the historic swath of space real estate that hoisted the crew of Apollo 11 — Neil Armstrong, Buzz Aldrin and Michael Collins — to the moon in 1969, as well as many space shuttle missions.

The launch was punctuated less than 10 minutes later, when the rocket booster returned to Earth and landed on a ship at sea so that it could be reused on another mission.

On board the SpaceX spacecraft were three NASA astronauts, Mike Hopkins, Shannon Walker and Victor Glover, as well as a Japanese astronaut, Soichi Noguchi. Though the space shuttle was capable of flying as many as eight people, Sunday’s flight was the first time four astronauts have ever flown in a capsule.

The crew will stay on board the space station for about six months, joining American Kate Rubins and Russian cosmonauts Sergey Ryzhikov and Sergey Kud-Sverchkov. The mission comes as NASA and its international partners this month are celebrating 20 years of continuous human presence on the space station, an orbiting laboratory about 250 miles above Earth.

If all goes according to plan, the four astronauts aboard the capsule should reach the space station at about 11 p.m. Monday.
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