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Full buck moon with a lunar eclipse visible this weekend – BC News – Castanet.net

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British Columbians were treated to a glorious full Strawberry Moon this June, but they’ll have the opportunity to view a magnificent full Buck Moon this July in addition to a lunar eclipse. 

Named after the time of year when young bucks begin to grow new antlers from their foreheads, the July full moon marks a time of renewal. The full Buck Moon will be at its fullest on July 4.

As the full moon increases in fullness, British Columbians will also be able to view a “penumbral lunar eclipse.” Timeanddate.com explains is set to begin July 4 at 8:07 p.m. but that it won’t be directly visible at that time.

At 9:22 p.m., “it will be rising but the the combination of a very low moon and the total eclipse phase will make the moon so dim that it will be extremely difficult to view until moon gets higher in the sky or the total phase ends.” 

The moon will be closest to the centre of shadow at 9:29 p.m. (-0.644 Magnitude). It will end at 10:52 p.m.

During this penumbral lunar eclipse, the Earth’s main shadow does not cover the Moon. 

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WTF, When Will Scientists Learn to Use Fewer Acronyms? – Lab Manager Magazine

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Have you heard of DNA? It stands for Do Not Abbreviate, apparently. Jokes aside, it’s the most widely used acronym in scientific literature in the past 70 years, appearing more than 2.4 million times.

The short form of deoxyribonucleic acid is widely understood, but there are millions more acronyms (like WTF: water-soluble thiourea-formaldehyde) that are making science less useful and more complex for society, according to a new paper released by Australian researchers.

Queensland University of Technology (QUT) professor Adrian Barnett and Dr. Zoe Doubleday from the University of South Australia (UniSA) have analyzed 24 million scientific article titles and 18 million abstracts between 1950 and 2019, looking for trends in acronym use.

Despite repeated calls for scientists to reduce their use of acronyms and jargon in journal papers, the advice has been largely ignored, their findings show in a paper published in eLife.

Many of the 1.1 million unique acronyms identified in the past 70 years are causing confusion, ambiguity, and misunderstanding, making science less accessible, the researchers say.

“For example, the acronym UA has 18 different meanings in medicine, and six of the 20 most widely used acronyms have multiple common meanings in health and medical literature,” according to Doubleday. “When I look at the top 20 scientific acronyms of all time, it shocks me that I recognize only about half. We have a real problem here.”

DNA is universally recognized, but the second most popular acronym CI (confidence interval) could easily be confused for chief investigator, cubic inch, or common interface. Likewise, US (United States/ultrasound/urinary system) and HR (heart rate/hazard ratio) often trip people up.

Barnett says the use of acronyms in titles has more than trebled since 1950 and increased 10-fold in scientific abstracts in the same period.

“Strikingly, out of the 1.1 million acronyms analyzed, we found that two percent (about 2,000) were used more than 10,000 times,” he says. “Even when the 100 most popular acronyms were removed, there was still a clear increase in acronym use over time.”

Entrenched writing styles in science are difficult to shift and excessive acronym use points to a broader communication problem in science, Doubleday says, but journals could help stem the trend by restricting the number of acronyms used in a paper.

“In the future it might be possible—software permitting—for journals to offer two versions of the same paper, one with acronyms and one without, so that the reader can select the version they prefer.”

This press release was originally published on the UniSA website

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Ask Ethan: Why Are The Moon And Sun The Same Size In Earth’s Sky? – Forbes

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In our Solar System, there’s one overwhelming source of mass that all the planets orbit around: our Sun. Each planet has its own unique system of natural satellites that exist in stable orbits around it: moons. Some moons, like Saturn’s Phoebe or Neptune’s Triton, are captured objects that were once comets, asteroids, or Kuiper belt objects. Others, like Jupiter’s Ganymede or Uranus’s Titania, formed from an accretion disk at the same time the planets of the Solar System formed. But from the surface of Earth, we have just one Moon — likely formed from an ancient, giant impact — and it just so happens to be practically identical in angular size to the Sun. Is that just a wild coincidence, or is there some reason behind this fact? That’s what Brian Meadows wants to know, asking:

“From a scientific point of view, what are the chances that the Moon and the Sun would appear the same size in the sky?”

It’s a great question, and one that still has great uncertainties surrounding it. Here’s what we know so far.

As far as moons of the Solar System go, there are four known ways that they naturally form.

  1. From the initial material that formed the objects of the Solar System; this is where most of the large moons around our gas giant planets come from.
  2. From collisions between a planet and another large body in space that kick up debris, where that material then coalesces into one or more moons around the planet.
  3. From other objects traversing the Solar System that become gravitationally captured by a parent planet.
  4. Or from material in a ring system around a planet that accretes to form a moon all on its own.
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When we examine the moons found in our Solar System, we find strong evidence of all four types.

But three of those types of moons — the ones that form from the initial Solar System material, the ones that get gravitationally captured, and the ones that form from accreted ring systems — are only found around the gas giant worlds in our Solar System. The moons that we find around smaller, terrestrial worlds, including Earth, Mars, and even objects like Pluto, Eris, and Haumea, are all consistent with their moons arising from one source and one source alone: ancient impacts between a large, massive, fast-moving body and the major world itself.

We didn’t always think this was the case, but an enormous suite of evidence now exists to support it. The Apollo missions returned samples of the lunar surface to Earth, where analysis confirmed that the material composing the Moon’s and the Earth’s crust have a common origin. Measurements of the composition and orbital parameters of Mars’s moons not only point to their creation from an impact, but indicate that a third, larger, inner moon was created, and has since fallen back to Mars. And most recently, measurements by New Horizons support a picture that Charon, Pluto’s giant moon (and likely the other, outer moons) all originated from a giant impact as well.

So if you’re asking a question like, “what are the odds that an Earth-like planet would have a Moon that’s approximately the same angular size as the Sun as seen from that same planet,” here are the facts we have to consider.

  • The only way that we know of, so far, to get a moon around a rocky planet like Earth is to have some sort of giant impact in the planet’s past.
  • We’ve only ever detected moons around rocky worlds in our Solar System, never around rocky exoplanets, as the technology to do so isn’t there yet.
  • Of the rocky planets, Mercury and Venus have no moons, Earth has just the one of this “miracle” size, while Mars’s two surviving moons both appear much smaller than the Sun.

And yet, when we consider the parameters of Earth’s moon with respect to how we observe it compared to the Sun, we experience a remarkable set of circumstances that no other known system possesses.

Here on Earth, the Moon orbits our planet in almost exactly the same plane that the Earth rotates on its axis: another piece of evidence that points to our Earth and Moon having a common origin from a giant impact. When the Moon happens to pass directly between the Earth and the Sun, and all three bodies are perfectly aligned, we experience a phenomenon known as a solar eclipse. This is common to all worlds with moons that cross the planet-Sun plane, but Earth and our Moon are unique in a very exciting way.

On Earth, we can experience three different types of solar eclipse with a perfect alignment:

  1. Total solar eclipse — where the Moon appears to entirely block out the disk of the Sun.
  2. Annular solar eclipse — where the Moon fails to block out the Sun’s disk, creating an annulus (or ring) of visible Sun circumscribing the eclipsing Moon.
  3. Hybrid solar eclipse — where the Moon fails to block the entire Sun for a portion of the eclipse, but does successfully block the entire Sun for a different portion.

Earth only experiences all three types of solar eclipse because the Moon, in its elliptical orbit around the Earth, can appear either larger or smaller than the Sun does due to Earth’s elliptical orbit around the Sun. This is no doubt a rarity; neither of Mars’s moons is ever large enough to eclipse the Sun totally, as every eclipse from Mars is annular. Moreover, if Mars did have a third, larger, inner moon at one point, its eclipses would have always been total eclipses; annular or hybrid eclipses would have been impossible.

But there’s another point to consider: these three possibilities weren’t always what Earth experienced, and they won’t always be what Earth experiences, either. The story of our Solar System, as best as we can reconstruct it, tells a tale of an ever-changing relationship between the Earth, Moon, and the Sun. It began some 4.5 billion years ago, where our ancient protoplanetary disk, which gave rise to all the planets, began to fragment into clumps that grew, interacted, and both merged and ejected one another. There were two types of survivors: large, massive planets that held onto hydrogen and helium envelopes, and smaller, less-decisive victors, which become planets and dwarf planets.

These early planets, planetoids, and planetesimals interact and sometimes collide, and those collisions — when they occur — tend to kick up large amounts of debris that surround the major planet. This shroud of post-impact material around the planet is known as a synestia, and although it’s short-lived, it’s incredibly important. Most of that material winds up falling back to the parent planet, while the rest coalesces into one or more moons. In general, the innermost moon will be the largest and most massive, and then you’ll have smaller, less massive moons that can exist at greater distances.

These moons exert differential forces on the planet: they gravitationally attract the portion of the planet that’s closer to the moon with a greater force than the portion that’s farther away. This not only creates tides on the planet, but it also results in what we call tidal braking, which causes the main planet to slow its rotation and the moon(s) to spiral away from the planet. Of course, there’s a competing effect: the planet’s atmosphere can create a drag force on the moon, drawing it closer to the planet. Depending on how the moons initially form, either effect can win.

In the case of Mars, the drag force appears to have won, drawing the innermost moon in; over time, the next moon, Phobos, will eventually fall back onto Mars as well. In the case of Pluto, tidal braking is complete, and the Pluto-Charon system is now a binary planet, where Pluto and Charon are both tidally locked to one another, surrounded by four additional, outer, smaller moons.

But the Earth-Moon system is fascinating. The current thought is that, early on, the Moon was very close to Earth, and there may have been a number of smaller, outer moons beyond our own. Earth, back more than 4 billion years ago, may have been rotating incredibly rapidly, completing a 360° rotation in just 6-to-8 hours. A year, back in Earth’s early history, may have had as many as 1500 “days” in it.

But over time, the tidal friction of the Moon slowed that rotation tremendously, an act which transfers angular momentum from the spinning Earth to the orbit of the Moon. Over time, this causes the Moon to spiral away from the Earth.

For billions of years, until only a few hundred million years ago, all of the solar eclipses on Earth were total eclipses; the Moon was close enough that it always blocked out the Sun from our perspective. In 570 million years, Earth will experience its final total solar eclipse, and in another 80 million years, its final hybrid solar eclipse. After that, all of Earth’s solar eclipses will be annular.

This means that when we look from Earth at the Moon today, and compare its angular size to that of the Sun today, we see three different types of solar eclipses, but that this is a temporary situation. The evidence indicates that, early on, the Moon was much larger in angular size than the Sun was, and that there may have been additional moons farther out. Over time, our Moon has spiraled away, and if there were smaller, more distant moons, they’ve been ejected. In the far future, the Moon will spiral out even farther, and will become eternally smaller in our sky than the Sun will ever be, for the remainder of its lifetime.

When you ask the question, “what are the odds that an Earth-like planet will have a Moon that’s comparable in angular size to the Sun,” you’re really asking what the odds are of:

  • having an Earth-like planet, which is an Earth-sized planet at the right distance from its star for liquid water on its surface,
  • that experienced a giant impact in its early history, creating a synestia,
  • where the planet itself winds up rotating rapidly after that collision,
  • where a large, inner moon gets created but won’t fall back onto the planet,
  • and then spirals away as angular momentum gets transferred from the planet to the Moon.

It’s remarkable that science, despite only having information about moons around terrestrial planets in our Solar System alone, has uncovered the ingredients necessary to create the situation we have today. If you assume you get an Earth-like planet, our best estimates have enormous uncertainties, but may lead to a total probability in the range of around 1-10%. To really know the answer to this question, however, we’ll need more and better data, and for that, we’ll need to wait for the next generation of astronomical observatories.

The answers are out there, written on the face of the Universe itself. If we want to find them, all we have to do is look.


Send in your Ask Ethan questions to startswithabang at gmail dot com!

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The 2020 Perseid meteor shower is still going strong: How to watch the show – MSN Money

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It’s mid-August, which means the annual Perseid meteor shower is active, and will be until Aug. 24. The Perseids are one of the best, brightest batches of shooting stars, and it feels like we could really use them now to add a bit of wonder and distraction into these pretty dismal times we’re living through.  






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Some 2019 Perseids, as seen from Macedonia. Spaceweather.com/Stojan Stojanovski

This famous shower comes around this time every year as the Earth drifts through a debris cloud left behind by the giant comet 109P/Swift-Tuttle. Bits of dust, pebbles and other cosmic detritus slam into our atmosphere, burning up into brief, bright streaks and even the occasional full-blown fireball streaking across the night sky. 


<span class="image" data-attrib="Spaceweather.com/Stojan Stojanovski" data-caption="

Some 2019 Perseids, as seen from Macedonia.

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a sky view looking up at night: Some 2019 Perseids, as seen from Macedonia.


© Spaceweather.com/Stojan Stojanovski

Some 2019 Perseids, as seen from Macedonia.


Technically, the 2020 Perseids peaked on the evening of Tuesday, Aug. 11 and morning of Wednesday, Aug. 12, but that doesn’t mean the show is over. Far from it, actually. 

The popularity of the shower is a combination of the fact that it’s one of the strongest, with up to 100 visible meteors per hour on average, and it’s coinciding with warm summer nights in the northern hemisphere. The waning moon is likely to wash out many otherwise visible meteors, but that still leaves plenty that should be easy to see if you do a little planning. 

In general, a good strategy is to head out to look for the Perseids as late in the evening as possible, but still before moonrise at your location. (You can look up sunset and moonrise for your location with a site like TimeandDate.com.)

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You can also try to block out the moon by situating yourself next to a building, tree or something else that keeps some of that moonlight out of your retinas. 

The moon will begin to totally disappear after mid-month, and although the Perseids will be past their prime, they will still be active and visible. This shower at half-peak with totally dark skies could be about the same as full peak with a bright moon, so don’t think you must go out on the peak night to catch it. 

Once you’ve decided on the perfect time and a place with minimal light interference and a wide view of the sky, just lie back, let your eyes adjust and relax. Pillows, blankets, lounge chairs and refreshments make for the ideal experience. It can take about 20 minutes for your eyes to adjust to the dark, so be sure to be patient. If you follow all my advice, you’re all but guaranteed to see a meteor. 

It doesn’t really matter where in the sky you look, so long as you have a broad view. That said, the Perseids will appear to radiate out from the constellation of Perseus, the Hero. If you want to practice to be an advanced meteor spotter, locate Perseus and try focusing there while you watch. Then try just looking up without focusing anywhere. See if you notice a difference. We’re still dealing with the unpredictability of nature, so results will vary. 

Arguably the best part of the Perseids each year are the gorgeous photos we get from talented astrophotographers spending long nights outside.

As always, if you capture any beauties yourself, please share them with me on Twitter or Instagram @EricCMack

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