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The Latest Flyby of Jupiter Has Offered Some of The Most Marvellous Views Yet – ScienceAlert

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Jupiter.

Most massive planet in the solar system – twice that of all the other planets combined. This giant world formed from the same cloud of dust and gas that became our Sun and the rest of the planets.

But Jupiter was the first-born of our planetary family. As the first planet, Jupiter’s massive gravitational field likely shaped the rest of the entire solar system.

Jupiter could’ve played a role in where all the planets aligned in their orbits around the Sun…or didn’t, as the asteroid belt is a vast region which could’ve been occupied by another planet were it not for Jupiter’s gravity.

Gas giants like Jupiter can also hurl entire planets out of their solar systems, or themselves spiral into their stars.

Saturn’s formation several million years later probably spared Jupiter this fate.

Jupiter may also act as a “comet catcher.” Comets and asteroids which could otherwise fall toward the inner solar system and strike the rocky worlds like Earth are captured by Jupiter’s gravitational field instead and ultimately plunge into Jupiter’s clouds.

But at other times in Earth’s history, Jupiter may have had the opposite effect, hurling asteroids in our direction – typically a bad thing but may have also resulted in water-rich rocks coming to Earth that led to the blue planet we know of today.

Jupiter is a window into our own solar system’s past – a past literally enshrouded beneath Jupiter’s clouds which is why Juno, the probe currently orbiting Jupiter, is so named. Juno, Jupiter’s wife in mythology, was able to peer through a cloak of clouds Jupiter used to hide himself and his wrongful deeds.

In this case, however, we are looking through Jupiter’s clouds into our own history. Juno entered orbit of Jupiter 5 July 2016 after travelling for nearly five years to reach the gas giant.

Falling into Jupiter’s gravity well, Juno arrived at a speed of 210,000 km/h, one of the fastest speed records set by any human-made object.

Juno is in a highly eccentric 53 day orbit. During Perijove, or the closest orbital approach, Juno skims Jupiter at an altitude of 4,200 km and then sweeps outward to 8.1 million km. Juno’s orbit is designed to navigate through weaker areas of Jupiter’s incredibly powerful magnetic field.

Second in power only to the Sun itself, Jupiter’s magnetic field accelerates high energy particles from the Sun creating powerful bands of radiation that encircle the planet – electronics-frying radiation.

In addition to its nimble navigation, Juno’s electronics are hardened against radiation with its “radiation vault” – a 1 cm thick titanium shell that houses its sensitive scientific equipment.

One piece of equipment which dazzles all of us back on Earth is JunoCam – an RGB colour camera taking visual images of Jupiter’s clouds as the probe buzzes the planet in just two hours each orbit spending as little time as possible in Jupiter’s radiation.

Most recently, Juno completed Perijove 29 and some of the photos were posted by “Software Engineer, planetary and climate data wrangler, and science data visualization artist” Kevin Gill.

Kevin has an absolutely astonishing Flickr page where he posts images he’s processed from Juno as well as other missions like Saturn’s Cassini and the HiRISE camera orbiting Mars on the Mars Reconnaissance Orbiter.

Okay. And finally, why you came here: Behold Juno’s Perijove 29 processed by Kevin Gill (You can click each image to see their full size).

50354102817 4f6d166d42Jupiter from Juno PJ29 – c. (NASA/JPL/Kevin Gill)

50353627451 a9fa985b6eJupiter from Juno PJ29 – c. (NASA/JPL/Kevin Gill)

50353886952 bf2d3931bcJupiter from Juno PJ29 – c. (NASA/JPL/Kevin Gill)

50354101847 08071ae129Jupiter from Juno PJ29 – c. (NASA/JPL/Kevin Gill)

50354243256 a7e10b77c1Jupiter from Juno PJ29 – c. (NASA/JPL/Kevin Gill)

50357320841 d7b91c2e95Jupiter from Juno PJ29 – c. (NASA/JPL/Kevin Gill)

50360879938 78cd2d56deJupiter from Juno PJ29 – c. (NASA/JPL/Kevin Gill)

You can also follow Kevin’s work on Twitter (@kevinmgill) and Instagram (@apoapsys).

JunoCam isn’t really part of Juno’s primary scientific mission. But the camera does provide a key function – allowing Juno to bring us along for the journey.

Which I think is truly spectacular. Sometimes astrophotography is thought more of as art than science.

But as an astrophotographer myself, I believe these images inspire future scientists, general awareness of ongoing scientific missions, and hopefully public support for the funding of science. Speaking of which, what has our science discovered about our giantest of giant worlds?

One of the greatest mysteries of Jupiter is what lies at its heart. Juno helped settle an ongoing debate in the planetary science community about how Jupiter formed.

There were two possibilities: The first is that Jupiter began as a rocky world – a core about 10 times the mass of Earth. The gravity of this core drew in surrounding hydrogen and helium until the Jupiter we know of was formed – that original rocky world buried beneath the churning maelstrom.

The second possibility is that eddies in the rotating protoplanetary disk of our early solar system collapsed on themselves and Jupiter formed from them directly with no rocky core. Both theories describe different conditions at the start of our solar system. Juno revealed something stranger, not a solid core, but a “fuzzy” or “diluted” core.

It appears that Jupiter did form from a rocky body, but rather than that core being situated at the centre of the planet, its is spread throughout the interior of Jupiter. 

The core’s dilution is likely the result of a massive planet-sized impact with Jupiter that shattered the initial core and spread it through half of Jupiter’s diameter.

Imagine being present for an event like that – Jupiter swallowing a would-be planet in our solar system we’ve never known. History of our place in space revealed.

We’ve also learned that Jupiter’s winds dive deep below the outer clouds, that the Great Red Spot is hundreds of kilometers deep, and we’ve seen giant cyclones at Jupiter’s North and South Poles that could swallow a country.  

Cyclones Size comparison JPL Caltech NASAJupiter South Polar Cyclones in Infrared with Size Comparison to US and Texas. (JPL/NASA/Caltech)

Jupiter is presently the brightest object in the night sky after sunset. If you have clear skies and can see it, look South!

Remember, that bright point is a giant world hundreds the times the size of Earth, millions of kilometers away, and yet potentially one of the key factors in your existence. By Jove, that’s amazing.

This article was originally published by Universe Today. Read the original article.

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NASA mission will touch down on asteroid Bennu today – CTV News

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After orbiting the near-Earth asteroid Bennu for nearly two years, NASA’s OSIRIS-REx spacecraft is ready to reach out its robotic arm and collect a sample from the asteroid’s surface on Tuesday. That sample will be returned to Earth in 2023.

A van-size spacecraft has to briefly touch down its arm in a landing site called Nightingale. The site is the width of a few parking spaces. The arm will collect a sample between 2 ounces and 2 kilograms before backing away to safety.

The site itself is nestled within a crater the size of a tennis court and ringed in building-size boulders.

Located more than 320 million kilometres from Earth, Bennu is a boulder-studded asteroid shaped like a spinning top and as tall as the Empire State Building. It’s a “rubble pile” asteroid, which is a grouping of rocks held together by gravity rather than a single object.

The mission — which stands for Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer — launched in September 2016.

Since arriving at Bennu, the spacecraft and its cameras have been collecting and sending back data and images to help the team learn more about the asteroid’s composition and map the best potential landing sites to collect samples.

The main event of the mission, called the Touch-and-Go sample collection event, or TAG, is scheduled for October 20 beginning at 5 p.m. ET.

Bennu has an orbit that brings it close to Earth, which is why it’s considered to be a near-Earth asteroid. One of its future approaches could bring it perilously close to Earth sometime in the next century; it has a one in 2,700 chance of impacting our planet.

The samples from Bennu could help scientists understand not only more about asteroids that could impact Earth but also about how planets formed and life began.

“It’s a historic first mission for NASA, returning an asteroid sample, and it’s hard,” said Thomas Zurbuchen, associate administrator of NASA’s Science Mission Directorate, during a Monday press conference.

“Bennu is almost a Rosetta Stone out there, and it tells the history of our Earth and solar system during the last billions of years. Bennu has presented a lot of challenges, but the ingenuity of the team has enabled us to get where we are.”

WHAT TO EXPECT

Rather than the so-called “seven minutes of terror” of trying to land the Perseverance rover on Mars next year, the OSIRIS-REx team is anticipating “4.5 hours of mild anxiousness,” according to Beth Buck, the mission’s operations program manager at Lockheed Martin Space in Littleton, Colorado.

During this time, the spacecraft will descend from its orbit around the asteroid and eventually come close enough to touch it.

The asteroid and spacecraft are currently about 207 million miles from Earth, which will cause a communication delay of about 18.5 minutes.

The team at NASA will livestream an animation depicting what is occurring based on the commands that have already been sent to OSIRIS-REx hours ahead for the sample collection sequence.

The spacecraft will perform the entire sequence of approaching the asteroid and collecting the sample autonomously since live commands from Earth won’t be possible.

TOUCHING DOWN ON AN ASTEROID

The event will take about 4.5 hours to unfold and the spacecraft will execute three maneuvers to collect the sample.

The spacecraft will first fire thrusters to leave its safe orbit around the asteroid, which is about 762 metres away from the surface, and travel for four hours before reaching just 125 metres away. Then, the spacecraft will adjust for position and speed to continue descending.

Next, OSIRIS-REx will slow its descent to target a path so it matches the asteroid’s rotation during contact. Its solar panels will fold into a Y-wing configuration above the spacecraft to protect them.

At last, OSIRIS-REx will touch down for less than 16 seconds. The spacecraft will fire a pressurized nitrogen bottle into the asteroid, using the gas as a way to lift material off Bennu’s surface.

The spacecraft’s collector head will capture the stirred up material. This head, located on the 3-metre-long robotic sampling arm, is the only part of the spacecraft that will touch Bennu. The team compares it to an air filter in an older model car, perfect for collecting fine material.

Small discs, which can collect dust like sticky pads, are also located on the head in case part of the sampling maneuver doesn’t go according to plan.

AfFTER THE EVENT

A camera on the spacecraft will take footage of the collection event.

The OSIRIS-REx spacecraft will have to detect hazards and delay its own mission if any obstacles get in the way of the sample collection. Based on its simulations, the team estimates there is less than a 6% chance the spacecraft will abort the mission.

By Tuesday night, the team should be able to confirm if the touchdown occurred successfully. Imagery will be returned by the spacecraft on Wednesday, which will provide more details of the sample collection and how the spacecraft is faring.

The team estimates that they will have a mass measurement of the sample on Saturday. By October 30, NASA will confirm if the spacecraft collected enough of a sample or if it needs to make another sample collection attempt in January at another landing site called Osprey.

But if everything runs smoothly, the spacecraft and its prized sample will begin the long journey back to Earth next year and land the sample on Earth in 2023.

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OSIRIS-REx mission to collect asteroid sample to return to Earth thanks to Canadian technology – CBC.ca

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On Tuesday, NASA’s OSIRIS-REx mission will make history as it attempts its first collection of material from an asteroid to be returned to Earth in 2023.

The spacecraft — which arrived at the asteroid Bennu in 2018 — will conduct a touch-and-go manoeuvre, also referred to as TAG. This crucial part of the mission was made possible in part by Canadian technology, specifically the Canadian Space Agency’s OSIRIS-REx Laser Altimeter (OLA), which mapped the surface of Bennu in 3D. The asteroid lies roughly 332 million kilometres from Earth.

That mapping turned out to be extremely important. Scientists and engineers had anticipated the asteroid to be mostly smooth and dusty. But that wasn’t the case.

“When we arrived we realized very, very quickly that there wasn’t a single area on the entire asteroid that was 50 metres across that had no obstacles,” said Tim Haltigin, senior mission scientist of Planetary Exploration at the Canadian Space Agency. 

“And so we really had to rethink our planning of how we were going to select a sample site and where we could safely deliver the spacecraft. And I think that’s one of the reasons why the OLA instrument became even more crucial in terms of understanding the roughness, the topography, the slopes of the surfaces … to really be able to pick a site where we knew that we could get the spacecraft down safely to collect a sample.” 

Mike Daly, OLA’S lead instrument scientist, said that he’s very pleased with the amount of detail and precision it was able to provide. 

“When I was thinking about what this instrument had to do and what it was — how it would perform — we had a much smoother Bennu, a much more boring Bennu in mind,” said Daly, who is also a professor at York University’s Lassonde School of Engineering in Toronto. “So when you see the detail that came out of this instrument, it’s just unbelievable. It blew us all away, honestly.

“So, we’re pretty proud of it.”

WATCH | A rendered rotation movie of Bennu taken by the Canadian OLA instrument:

The Canadian Space Agency’s OSIRIS-REx Laser Altimeter was crucial in mapping the asteroid Bennu ahead of its “touch-and-go” mission to collect samples that will be returned to Earth in 2023. Credit: Mike Daly, et. al 0:51

Daly has been working on the instrument for 12 years, while Haltigin has been working on it for seven years. Both men said that it’s become a part of their lives.

“It’s a little bit bittersweet,” Daly said.

The great part about the sample-return mission is that, because Canada is a partner, it gets some of the material. It’s something that Haltigin is extremely excited about.

“It’s going to be owned by Canada, and so we’re going to be able to make these samples available for generations and generations of Canadian scientists,” he said. “So, we’re basically enabling the next 50 to 100 years of discoveries based on these samples.”

‘Kissing the surface’

Rather than landing on the asteroid’s surface, a set of manoeuvres will be conducted in order to collect material.

“Due to the low gravity, we can’t actually land on the surface of Bennu. So we’ll only be kissing the surface with a short touch and go, measured in just seconds,” Beth Buck, OSIRIS-REx mission operations program manager for Lockheed Martin Space, said in a teleconference on Monday.

Compressed nitrogen gas will be pumped out onto the surface, which will stir up particles that will then be collected by a sampler.

The collection will take place at 6:12 p.m. ET and will be broadcast live on NASA TV. It can also be watched on CBC.ca beginning at 5 p.m. 

A Canadian laser made a 3D map of Bennu, helping find the best sample site for NASA’s OSIRIS-REx mission. (Canadian Space Agency)

It will take roughly 18.2 minutes for a signal to be received from the spacecraft. However, while NASA expects to get confirmation that the manoeuvre took place on Tuesday, it won’t know for certain until Wednesday if material was successfully collected.

The OSIRIS-REx spacecraft has gone through a couple of rehearsals of the manoeuvre, one in April and another in August, so NASA hopes it will be successful. However, it does have two more opportunities to collect material should this be unsuccessful.

It’s not the first time material has been collected from an asteroid. The Japanese Space Agency, JAXA, is currently awaiting the return of the Hayabusa2 spacecraft with a sample from the asteroid Ryugu, scheduled to return in December. 

Think of asteroids as time capsules

OSIRIS-REx launched in 2016 and arrived at Bennu in December 2018. Since then, it has been in orbit around the asteroid.

Bennu is about 492 metres in diameter and orbits the sun once every 1.2 years. It wasn’t discovered until 1999 and wasn’t given an official name — chosen by a Grade 3 student from North Carolina — until 2012 (the name refers to an Egyptian mythological bird).

The asteroid is believed to be roughly 4.5 billion years old, as old as the solar system itself. And that’s key: astronomers hope that Bennu can shed some light on how the solar system formed and how ultimately life may have arisen on Earth.

“Collecting a sample from an asteroid is the equivalent of going back in time by over four billion years to understand what the early solar system was made of,” said Haltigin.”So, you can think of asteroids almost as time capsules that have preserved the materials from the very formation of the solar system.” 

There is also a very small chance that Bennu will collide with Earth. But there’s no need to panic: there’s only a one in 2,700 chance that will happen between the years 2175 and 2199, according to NASA.

For now, scientists and engineers will be on the edge of their seats, awaiting confirmation that the mission was successful. And the asteroid is bound to have some surprises.

“What excites me the most, I’ll be perfectly honest, is we’re going to find out something that nobody expected, and I don’t know exactly what that is,” Haltigin said. “But I do know that we are going to be shocked and surprised and amazed once we figure it out.”

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What’s Happening with Betelgeuse? Astronomers Propose a Specialized Telescope to Watch the Star Every Night – Universe Today

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Starting in late 2019, Betelgeuse began drawing a lot of attention after it mysteriously started dimming, only to brighten again a few months later. For a variable star like Betelgeuse, periodic dimming and brightening are normal, but the extent of its fluctuation led to all sorts of theories as to what might be causing it. Similar to Tabby’s Star in 2015, astronomers offered up the usual suspects (minus the alien megastructure theory!)

Whereas some thought that the dimming was a prelude to the star becoming a Type II supernova, others suggested that dust clouds, enormous sunspots, or ejected clouds of gas were the culprit. In any case, the “Great Dimming of Betelgeuse” has motivated an international team of astronomers to propose that a “Betelgeuse Scope” be created that cant monitor the star constantly.

The paper that outlines their proposal was recently presented at the International Society for Optics and Photonics (SPIE) Optical Engineering + Applications 2020, a virtual conference that took place from Aug. 24th to Sept. 4th. The paper, “Betelgeuse scope: single-mode-fibers-assisted optical interferometer design for dedicated stellar activity monitoring,” is also available online as part of the Proceedings of SPIE, Vol. 11490.

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To recap, Betelgeuse is a red giant star that is about 12 times as massive as our Sun and about 900 times as large. It is located about 700 light-years from Earth in the Orion constellation and is easily spotted by looking for “the Hunter’s” left shoulder. Ordinarily, Betelgeuse is the second-brightest star in Orion (after Rigel) and the tenth-brightest star in the night sky.

Starting in November of 2019, the star began to dim rather suddenly, reaching a historical minimum of just 37% of its average brightness by Feb. 10th, 2020. At this point, Betelgeuse began to brighten until the end of May, at which point the dimming started all over again. For the sake of their article, the team explored different theories as to what caused the dimming.

This included the “Dark Spots hypothesis,” which was based on submillimeter observations taken by the James Clerk Maxwell Telescope and Atacama Pathfinder Experiment. Then there’s the “Dust formation and blocking hypothesis,” which is based on observations conducted with the VLT/SPHERE and the Hubble Space Telescope that suggest that there was a mass ejection from a large convective cell in the photosphere.

According to the authors, all of these possibilities can be investigated by observing the change of Betelgeuse’s angular diameter accurately. In order to do this, telescopes that are capable of conducting high-angular resolution observations (such as optical interferometry) would be needed. In this process, visible light is gathered by two or more telescopes and then combined to obtain higher-resolution images.

Graphic showing how Betelgeuse could be dimming. Credit: NASA, ESA, and E. Wheatley (STScI)

As they state in their study, today’s optical telescope facilities are not optimized for the kind of time-evolution monitoring that would be needed. In short, conducting this type of campaign would mean committing observation time from multiple facilities, which is a very expensive prospect. For this reason, the team recommends that a telescope be commissioned for the task.

As Dr. Narsireddy Anugu, a Prize Fellow in Astronomical Instrumentation and Technology at the University of Arizona’s Steward Observatory and the lead author on the study, explained to Universe Today via email:

“High-angular observations are required to image any existing dark spots on the Betelgeuse’s surface and ‘rogue’ convection cells. Collaborators [are also needed], and we have been taken some data with the Very Large Telescope Interferometer at Paranal, Chile (led by M. Montarges) and the CHARA array at the Mount Wilson Observatory. We are currently working on image reconstruction of interferometry data to reveal any dark spots and convection cells on the Betelgeuse surface.”

As they describe it, this “Betelgeuse Scope” will leverage advancements made in the field of optical interferometry and the telecommunication industry. It will consist of an array of 12 x 4 inch Cassegrain-reflector optical telescopes, which will be mounted to the surface of a large radio dish, which will allow for snapshot imaging of convection cells and time-evolution monitoring. As Dr. Anugu described it:

“We have proposed a unique six telescope interferometer concept installing on a radio antenna. This concept aims at a low budget by cutting the costs of pointing and tracking of each individual telescope using the already existing pointing and tracking of the radio antenna. Another benefit of installing the telescope array on a common mount is that we don’t need longer delay lines as in the classical non-common mount based long-baseline interferometers. Where an active compensation of changing the geometrical delay is required between the wavefronts reaching any two telescopes.”

Artist’s impression of a red supergiant star, of which interferometry has allowed detailed observations to be made. Credit: ESO/M. Kornmesser

Polarization-maintaining single-mode optical fibers will then carry the coherent beams from the individual optical telescopes to a central beam-combining facility. To compensate for atmospheric turbulence, vibrations, and pointing errors caused by windy conditions, the team recommends a fast steering mirror, a standard tip-tilt correction system, a fast frame rate detector, and a metrology laser system to measure vibrations.

In addition to being able to monitor Betelgeuse and resolve the mystery of its dimming, the Betelgeuse Scope will also allow for significant advancements in the field of astronomy. Said Dr. Anugu:

“Our proposed telescope monitors the Betelgeuse every-night with high-angular resolutions, makes a movie of motion of dynamic convection activity on the surface. This way, we will probe future mysterious dimming events such as 2019-2020 and origins of the dust formation around the Betelgeuse.”

At present, Anugu and his team are building a prototype of their proposed telescope, which will be mounted on the University of Arizona’s 6-meter (~20 foot) radio dish. So far, they have procured one set of light-collecting and fiber injection optics (12 are needed overall) and are integrating them into their lab at the Steward Observatory. They anticipate that the prototype will be finished and ready to be installed by the end of the year.

“Our proposed concept is straight forward, but we are building a pathfinder to test them,” said Dr. Anugu. “Once successful, we reuse the same optics and actuators for the actual 12-m radio antenna, and 12 telescope interferometer array as this concept is scalable and modular.”

Further Reading: arXiv

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