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How to watch Mars shine bright during opposition Tuesday night – CNET

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Mars will bright and beautiful in the October 2020 night sky.


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Forget Halloween. October 2020 is all about the glory of Mars, as the glimmering red planet puts on a show in the night sky. We passed Mars’ close approach to Earth on Oct. 6 and now we’re looking forward to Tuesday, Oct. 13, when it will be in opposition. 

Spotting Mars

Mars has a reputation as the “red” planet, but its color in the night sky is a little more on the Halloween side of the spectrum. It appears as a bright orange-red dot to the naked eye, like a little spot of glittering rust.

Mars’ distinctive color is one clue you’ve found it in the dark. Look to the eastern sky to catch it rising at night. This is a great time for viewing the planet, partly because spotting it is so simple. It should be visible for most of the night. As NASA says, “Simply go outside and look up and, depending on your local weather and lighting conditions, you should be able to see Mars.”

Check out our list of stargazing apps if you want some extra help with locating the planet.

Opposition: Oct. 13

When Mars and the sun line up with Earth in the middle, the red planet is said to be in opposition. This is a perfect time to track Mars’ movement across the sky. It will rise in the east as the sun goes down, move across the sky and then set in the west as the sun comes up. 

NASA describes opposition as “effectively a ‘full’ Mars.” Tuesday, Oct. 13 is the time to enjoy opposition. You’ll have to wait over two years for it to happen again. 

The Virtual Telescope Project, which brings us live feeds of celestial events, will stream a Mars opposition viewing starting at 1 p.m. PT. on Oct. 13. It’s a perfect way to enjoy the action without weather worries. For people in the US, it will give you a preview of what to look for after sundown. 

The project expects this to be “the best observing conditions since July 2018.” 

“The racetrack model of planetary orbits explains why. Earth and Mars are like runners on a track. Earth is on the inside, Mars is on the outside,” NASA said in its What’s Up blog for October. “Every 26 months, speedy Earth catches up to slower Mars and laps it. Opposition occurs just as Earth takes the lead.”

Mars isn’t the only show-off in the sky for October. You can also look forward to a rare Halloween blue moon when our lunar neighbor is full on Oct. 31. It’s not spooky; it’s boo-tiful.

Rewind to the close approach on Oct. 6

Tuesday, Oct. 6 marked the close approach of Mars to Earth, but this entire month is still a good time to grab a telescope and get a little better look. Give a wave to NASA’s Perseverance rover while you’re at it. The vehicle is on track to reach the planet in February 2021. 

NASA shared an artist’s view of the Tuesday, Oct. 6 close approach compared with the last time it snuggled up in July 2018. The apparent sizes look very similar. This year, Mars had a minimum distance of 38.6 million miles (62 million kilometers), which is about 3 million miles farther away than in 2018. 

This artist’s view shows the apparent sizes of Mars during close approaches in 2018 and 2020. 


NASA

Close approach may be over, but the planet is still plenty bright in the night, so get out and take a gander, or tune into the Virtual Telescope Project’s live feed from the comfort of your computer. 

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These Tiny, Little-Winged Dinosaurs Were Probably Worse at Flying Than Chickens – ScienceAlert

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The discovery of two small dinosaurs with bat-like wings a few years ago was a palaeontologist’s dream. Just how flight evolved in birds is something we’re still trying to nail down, and looking at this early evolution of bat-like wings in dinosaurs could give us a clue.  

But a team of researchers has now pointed out that just because you have wings, it doesn’t necessarily mean you’re actually any good at flying.

Yi qi and Ambopteryx longibrachium are two species of theropod dinosaurs that lived around 160 million years ago, both of which had unusually elongated fingers, and a skin membrane stretching between them, similar to a bat’s wing.

This is an entirely different kind of wing to the one theropod dinosaurs evolved to fly with – the dinosaurs that eventually became birds. And, unlike them, after only a few million years, Yi and Ambopteryx became extinct, which is the first hint that these unusual wings could not match those birds-to-be. 

However, weird wings on extinct critters mean it’s likely multiple types of wings (and therefore flight) evolved over the years, and that Yi and Ambopteryx’s attempts were not the winning strategy.

But before you can write off Yi and Ambopteryx as complete evolutionary flight failures, you have to know how good (or bad, as the case may be) the two species were at flight.

In 2015, when Yi was found, that team of researchers suggested that the size of its wings and other flight characteristics could mean it was a gliding creature – however it’s unlike any other glider we know of, and its centre of mass might have made even gliding difficult. We just weren’t sure.

A new study, by researchers in the US and China, has now looked into the flight potential of Yi and Ambopteryx in a lot more detail, and come to the conclusion that they really weren’t good at getting their little feet off the trees they lived in.

“Using laser-stimulated fluorescence imaging, we re-evaluate their anatomy and perform aerodynamic calculations covering flight potential, other wing-based behaviours, and gliding capabilities,” the team writes.

“We find that Yi and Ambopteryx were likely arboreal, highly unlikely to have any form of powered flight, and had significant deficiencies in flapping-based locomotion and limited gliding abilities.”

The team’s analysis of the fossils (Yi pictured below) was able to pick up tiny details in soft-tissue that you can’t see with normal light.

Fossil of Yi qi. Look how fluffy it is! (kmkmks/Flickr/CC BY SA 2.0)

Then the team modelled how the dinosaurs might have flown, adjusting for things such as weight, wingspan, and muscle placement (all stuff we can’t tell just from the fossils).

The results were… underwhelming.

“They really can’t do powered flight,” says first author, biologist Thomas Dececchi from Mount Marty University.

“You have to give them extremely generous assumptions in how they can flap their wings. You basically have to model them as the biggest bat, make them the lightest weight, make them flap as fast as a really fast bird, and give them muscles higher than they were likely to have had to cross that threshold. They could glide, but even their gliding wasn’t great.”

gr1Soft-tissue map of Yi qi. (Dececchi et al., iScience, 2020)

So, according to Dececchi and his team’s model, we’re looking at flying capabilities considerably worse than a chicken, perhaps worse than the flightless New Zealand parrot, the kakapo, which is also mostly limited to gliding from trees, but can at least flap to control descent.

But although it’s a bit sad for the Yi and Ambopteryx, it’s good news for us – the findings give even more evidence that dinosaurs evolved flight (or at least tried to) multiple times.

As the team points out, considering all the types of bats, gliders, flying squirrels, and other gliding or flying mammals, maybe it shouldn’t be a surprise.

“We propose that this clade was an independent colonisation of the aerial realm for non-avialan theropods. If true, this would represent at least two, but more likely three or more attempts at flight (both powered and gliding) by small pennaraptoran theropods during the Mesozoic,” the team writes in their paper.

“Given the large number of independent occurrences of gliding flight within crown mammals, this should perhaps be unsurprising, but it does create a more complex picture of the aerial ecosystem.”

Seems like some things don’t change much, even in a hundred million years.

The research has been published in iScience.

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NASA Spacecraft Osiris-Rex Extracts Samples From Asteroid Bennu, a First for US – The Daily Beast

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NASA Spacecraft Osiris-Rex Extracts Samples From Asteroid Bennu, a First for U.S.

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'Weird bat-winged' dinosaurs glided through treetops in attempt at flight: study – CTV News

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TORONTO —
A new study investigating the flight capabilities of two tiny dinosaurs with thin, bat-like wings is shedding light on the evolution of avian flight itself — an evolution that, it turns out, had a lot of dead ends and false starts along the way.

Published in the journal iScience earlier this week, the study looked at Yi and Ambopteryx, two dinosaurs who lived around 160 million years ago in the Late Jurassic era of China. Both were believed to have the potential for flight due to the thin membranes stretched between their arms and their bodies.

However, when researchers applied mathematical modelling to these prehistoric creatures, they found that they were nowhere near capable of propelling themselves through the air like birds, and instead would’ve used their small wings only to glide.

“We know some dinosaurs could fly before they evolved into birds,” Hans Larsson, a professor at McGill University and Director of McGill’s Redpath Museum, said in a press release. “What this shows us is that at least one lineage of dinosaurs experimented with a completely different mode of aerial locomotion.”

A ‘WEIRD BAT-WINGED’ PAIR

Researchers scanned fossils of Yi and Ambopteryx with lasers to pick out where the soft tissue would fall on their wings, details that couldn’t be seen under regular light.

Then they reconstructed the dinosaurs’ morphology with computer modelling to see whether they could power themselves to flight, whether by leaping from trees or from the ground. They also changed important variables like wingspan and body weight to assess different scenarios on how they might have flown.

In order to flap their wings with enough force to support their own body, the dinosaurs would’ve needed strong pectoral muscles, which were absent. Ambopteryx could only take off in flight at the lowest estimated body size and highest estimated power level, and Yi could not obtain any lift-off except at body weights researchers said were likely too small to be accurate. In almost all scenarios, the dinosaurs could not get off the ground under their own power.

Even with a running start to help them, the minimum take off speed for Yi would be between 1.1 and three times the maximum possible speed Yi would have been capable of. For Ambopteryx, the minimum take-off speed was even more out of reach, needing to be at least 2.3 to four times their top sprinting speed.

The two dinosaurs were capable of gliding if they leaped from trees — but not well. The research found that compared to other dinosaurs capable of gliding or flying, these two “show poorly developed gliding abilities.”

Both Yi and Ambopteryx would have to launch from higher points in trees at higher speeds than other creatures that glide, and they would be less precise when they landed.

They are thought to have spent most of their lives in trees, eating insects, seeds and plants.

AVIALANS AND THE EVOLUTION OF FLIGHT

Many modern creatures can glide, but only pterosaurs, bats and birds developed the structures necessary to fly by flapping their wings.

It’s well known that modern day birds are descendants of dinosaurs, but this new research adds a complication to the predominant theory of how avian flight came about.

The majority of dinosaurs with flying capabilities — called avialans — have had very similar characteristics and body types, and different families of dinosaurs who have evolved towards flight have started as ground-dwelling creatures and gone through similar body changes — such as a reduction in body size, getting an increased shoulder mobility and developing feathers on their four limbs — before gaining the ability to fly.

This has told a reasonably streamlined tale about the evolution of flight from dinosaurs to birds for the most part, the study explained.

But Yi and Ambopteryx are outliers, showing that dinosaur flight went through some bumps on the road.

Both are therapods, a categorization of carnivorous dinosaurs with hollow bones that includes the T-rex and birds, but they’re also part of a little-understood group called Scansoriopterygidae, which are climbing and gliding dinosaurs.

It’s been posited before that scansoriopterygids could represent an interim stage before avialans, an early model of bird flight that then evolved to support more powered flying. But researchers say this was far more likely an independent attempt at flight, a “failed experimental lineage of early arboreal gliders” unconnected to the evolution of avialan flight.

“Given the large number of independent occurrences of gliding flight within crown mammals, this should perhaps be unsurprising, but it does create a more complex picture of the aerial ecosystem,” the study stated.

“We used to think of birds evolving as a linear trend from their ground-dwelling dinosaur ancestry,” Larsson said in the release.

“We can [now] revise this textbook scenario to one that had an explosive diversity of experimentation, with dinosaurs evolving powered flight several times independently from birds, many having fully feathered wings but with bodies too heavy or wings too small to have gotten off the ground, and now, a weird bat-winged group of dinosaurs that were not only the first arboreal dinosaurs, but ones that glided.”

He added that he feels like researchers are “still just scratching the surface,” of dinosaur biodiversity.

Yi, Ambopteryx and others scansoriopterygids had a short-lived existence, unable to compete with the mammalian gliders and avialan fliers that were evolving around them.

Both dinosaurs went extinct after only a few million years, according to the press release.

“Once birds got into the air, these two species were so poorly capable of being in the air that they just got squeezed out,” lead author Thomas Dececchi, an assistant professor of biology at Mount Marty University, said in the release. “Maybe you can survive a few million years underperforming, but you have predators from the top, competition from the bottom, and even some small mammals adding into that, squeezing them out until they disappeared.”

Gliding isn’t an efficient way to get around, as you have to climb to a great height first to travel any sort of distance, he explained.

“It’s not efficient, but it can be used as an escape hatch. It’s not a great thing to do, but sometimes it’s a choice between losing a bit of energy and being eaten. Once they were put under pressure, they just lost their space.

“They couldn’t win on the ground,” he said. “They couldn’t win in the air. They were done.”

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