Space News/UFO's Etc...(Discussion/Pics/Vids)

[ilan]

VLT Survey Telescope Observes Messier 18
News Staff, Science News | Aug, 10, 2016

ESO’s VLT Survey Telescope at Paranal Observatory, Chile, has captured a new image of the star cluster Messier 18, also known as NGC 6613 and M18.
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Messier 18 (upper left) and its surroundings. This image was captured by the OmegaCAM, a camera installed on the VLT Survey Telescope. Image credit: ESO.[/TD]
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Messier 18 is an open star cluster located in the constellation Sagittarius.

It spans about 18 light-years across and is at a distance of 4,230 light-years from Earth.

It was discovered in 1764 by the French astronomer Charles Messier during his search for comet-like objects.

There are over 1,000 known open clusters within our Milky Way Galaxy, with a wide range of properties, such as size and age, that provide astronomers with clues to how stars form, evolve and die.

The main appeal of these clusters is that all of their stars are born together out of the same material.

In Messier 18 the blue and white colors of the stellar population indicate that the cluster’s stars are very young, probably around 30 million years old.

Being siblings means that any differences between the stars will only be due to their masses, and not their distance from Earth or the composition of the material they formed from. This makes clusters very useful in refining theories of star formation and evolution.

Scientists now know that most stars do form in groups, forged from the same cloud of gas that collapsed in on itself due to the attractive force of gravity.

The cloud of leftover gas and dust that envelops the new stars is often blown away by their strong stellar winds, weakening the gravitational shackles that bind them.

Over time, loosely bound stellar siblings like those pictured here will often go their separate ways as interactions with other neighboring stars or massive gas clouds nudge, or pull, the stars apart.

Our Sun was most likely once part of a cluster very much like Messier 18 until its companions were gradually distributed across the Milky Way.

The dark lanes that snake through this image are murky filaments of cosmic dust, blocking out the light from distant stars.

The contrasting faint reddish clouds that seem to weave between the stars are composed of ionized hydrogen gas.

The gas glows because young, extremely hot stars like these are emitting intense UV light which strips the surrounding gas of its electrons and causes it to emit the faint glow seen in this image.

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Globular clusters are different. The stars in globular clusters are held together by gravity and do not wander away as do stars in open clusters. - Ilan

 

[Capt.Kangaroo]

Just a reminder....

Perseids: Meteor Shower Expected to Peak Friday, NASA Says

The Perseid shower, which originates from the Swift-Tuttle comet, will continue until Aug. 24, NASA told Space.com. It can be best seen from a northeastern direction from the northern hemisphere.

 

[ilan]

How a 1967 Solar Storm Nearly Led to Nuclear War
Mike Wall, Space.com Senior Writer | August 9, 2016 05:07pm ET
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The sun as seen on May 23, 1967. A powerful flare erupted from the bright area in the top-center of the solar disk.
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A powerful solar storm nearly heated the Cold War up catastrophically a half century ago, a new study suggests.

The U.S. Air Force began preparing for war on May 23, 1967, thinking that the Soviet Union had jammed a set of American surveillance radars. But military space-weather forecasters intervened in time, telling top officials that a powerful sun eruption was to blame, according to the study.

"Had it not been for the fact that we had invested very early on in solar and geomagnetic storm observations and forecasting, the impact [of the storm] likely would have been much greater," Delores Knipp, a space physicist at the University of Colorado Boulder and the study's lead author, said in a statement. "This was a lesson learned in how important it is to be prepared."

The storm began brewing on May 18, 1967, when researchers noticed a big group of sunspots with strong magnetic fields clumped on one part of the solar disk.

Sunspots — dark, relatively cool areas on the sun's surface — serve as launching pads for powerful bursts of high-energy radiation known as solar flares, as well as eruptions of solar plasma called coronal mass ejections (CMEs), which almost always accompany strong flares.

Intense flares that hit Earth can disrupt radio transmissions and satellite communications, among other effects. Earth-directed CMEs can be even more damaging; big ones can spawn "geomagnetic storms" that blow out transformers in power grids, for example.

On May 23, 1967, the sun fired off a flare so powerful that it was visible to the naked eye, and began emitting radio waves at a level that had never been seen before, study team members said.

That same day, all three of the Air Force's Ballistic Missile Early Warning System radar sites in the far Northern Hemisphere — which were located in Alaska, Greenland and the United Kingdom — appeared to be jammed.

Air Force officials initially assumed that the Soviet Union was responsible. Such radar jamming is considered an act of war, so commanders quickly began preparing nuclear-weapon-equipped aircraft for launch. (These newly scrambled aircraft would have been "additional forces," according to the study authors; the U.S. kept nuke-bearing "alert" planes aloft pretty much continuously throughout the 1960s.)

"This is a grave situation," Knipp said. "But here's where the story turns: Things were going horribly wrong, and then something goes commendably right."

Those additional forces never launched. So what happened? Solar forecasters at the North American Aerospace Defense Command (NORAD) — a joint U.S.-Canadian effort that looks out for incoming missiles and other possible threats — and elsewhere figured out that the flare, not the Soviets, had disrupted the radars. (The U.S. military had begun keeping tabs on solar activity, and its effects on Earth, in the 1950s; by 1967, NORAD was getting daily updates on the subject, study team members said.)

Knipp and her colleagues think this information made it in time to Air Force commanders and other high-ranking officials — including, perhaps, President Lyndon Johnson.

"Oftentimes, the way things work is, something catastrophic happens, and then we say, 'We should do something so it doesn't happen again,'" Morris Cohen, an electrical engineer and radio scientist at the Georgia Institute of Technology in Atlanta, said in the same statement. "But in this case, there was just enough preparation done just in time to avert a disastrous result," added Cohen, who was not involved in the new study.

A solar superstorm

The flare on May 23, 1967, was accompanied by a CME, which hit Earth about 40 hours later. (CMEs travel through space at millions of miles per hour — fast, but not nearly as fast as solar-flare radiation, which, of course, moves at the speed of light.)

The CME triggered a powerful geomagnetic storm, which disrupted American radio communications for nearly a week, study team members said. This storm also ramped up the northern lights, making them visible as far south as New Mexico.

"As a magnetospheric disturbance, the 25-26 May event ranks near the top in the record books," Knipp and her colleagues wrote in the new study, which has been accepted for publication in the journal Space Weather.

The top spot in the record books, incidentally, likely belongs to the famous Carrington Event of September 1859. That geomagnetic storm caused telegraph systems to fail all over North America and Europe, and the northern lights were visible as far south as the Caribbean.

A Carrington-like storm today would likely be devastating, given how much more dependent the world is on technological infrastructure such as power grids and satellite networks, experts have said.

 

[ilan]

Solar Flare Unleashes Violent Plasma 'Rain' (Video)
By Samantha Mathewson, Space.com | August 8, 2016 05:42pm ET
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Bright loops of superheated plasma danced over the surface of the sun during a violent solar "rain" witnessed by NASA's Interface Region Imaging Spectrograph (IRIS).

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The IRIS satellite caught a video of this spectacular solar activity on July 24, and NASA released the footage Friday (Aug. 5). The loops of plasma, or electrically charged gas, were generated by a medium-strength solar flare that unleashed a large amount of magnetic energy.

When this material erupts from the solar surface, it shoots into the sun's atmosphere before cascading down in the giant arcs seen in the video. NASA scientists call this flare-driven event post-flare loops or coronal rain.

Coronal rain is driven by similar processes that trigger weather patterns on Earth. Much like the water vapor that forms clouds in Earth's atmosphere, the superhot plasma loops in the sun's outer atmosphere — called the corona — cool, condense and fall back down to the sun's surface.

"The details of how this happens is a mystery that scientists continue to puzzle out," NASA officials said in a statement.

IRIS has been making close-up observations of the sun's surface since its launch in 2013. Keeping a close eye on solar flares helps researchers learn more about the movement of material and energy in the sun's lower atmosphere.

Watch the Video:

http://www.space.com/33667-sun-s-plasma-rain-captured-in-high-detail-by-nasa-probe-video.html

 

[ilan]

Was Venus once habitable?
Ashley Strickland, CNN | Updated 11:49 AM ET, Sat August 13, 2016

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Research suggests Venus may have had water oceans billions of years ago. A land-ocean pattern was used in a climate model to show how storm clouds could have shielded ancient Venus from strong sunlight and made the planet habitable.[/TD]
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(CNN) Imagine a mostly dead planet with a heavy, toxic atmosphere 90 times thicker than ours and surface temperatures that reach 864 degrees: hot enough to melt lead.

That would be Venus, often called Earth's twin because they're similar in size. You couldn't live there if you wanted to.

But 3 billion years ago, things might have been different, according to a new study.

Scientists at NASA's Goddard Institute for Space Studies in New York took computer modeling that has predicted future climate change on Earth and applied it to Venus with the hopes of revealing what the young planet was like.

What they discovered made Venus seem a little friendlier and more like our own planet. They believe it had a shallow ocean and hospitable surface temperatures slightly cooler than Earth's for possibly 2 billion years of its early history. Big puffy clouds would have created overcast days that shielded the surface from heat and radiation.

Less is known about the ocean, which was first suggested by NASA's Pioneer mission in the 1980s. But given its placement as the second planet from the sun, Venus wasn't conducive to sustaining an ocean.

Venus receives more sunlight than Earth, which would evaporate liquid water, sending hydrogen into space and trapping a buildup of carbon dioxide. That would lead to a nonstop greenhouse effect that would create its current toxic atmosphere. Venus' topography was also completely altered by volcanic eruptions that most likely filled in lowland regions and potential ocean basins over the past billion years.

Because of this, past research to model the planet would simply place a duplicate of Earth and its topography in Venus' orbit. But a team of researchers, including lead study author Michael Way of NASA, wanted to create the first 3-D model of the planet using its current topography. Even if it isn't entirely accurate for the time period they were modeling, "it's the least wrong choice you can make," Way said.

Using past research, Way and his team knew that habitable factors for planets include rotation speed and topography. Venus rotates rather slowly, in the opposite direction of Earth and most planets, which researchers thought was due in part to its thick atmosphere. But recent research suggested that the same rotation rate would be possible with a thin atmosphere, as well.

"I knew that it probably would help the world maintain a quite temperate climate, as we found when we ran the model," Way said.

Was there life on Venus?

With this model, early Venus sounds rather cozy, so could it have supported life?

"Water does not equal life," Way stressed. "What we believe is that water is conducive to life. Venus is a much tougher place for life to get started. It was only warm and wet very early in its history. It's been a mostly dead planet for the last 4 billion years. But the modeling we did was to say that Venus might be a better place to look for the beginnings of life."

This can also be connected to evidence that suggests Earth and Venus have similar compositions, Way said. If Venus had a stable, warm, wet climate for longer than had been speculated, it could be due to the fact that the planet has a carbon cycle and structure similar to our own subduction plate tectonics. Both planets have a wealth of carbon dioxide: Earth through its lithosphere and rocks and Venus in its atmosphere.

Venus also has twice as much nitrogen in its atmosphere as Earth, and it's the most abundant gas in our atmosphere.

More missions in the future may be able to prove how much water Venus had, how it lost its water and over what time span, maybe even revealing what was on the surface in addition to water, Way said.

Modeling Earth and other planets

The larger goal from this study is to expand the capabilities of the model to look closer at what early Venus, Mars and even Saturn's moon Titan were like, using NASA's Planetary Science Astrobiology program and the Nexus for Exoplanet System Science. We can also look into our own past at early Earth, raising a wealth of questions scientists want to answer.

"There is this big puzzle called the faint young sun paradox, where the sun was 30% less luminous 3 billion years ago," Way said. "We know from the geologic record that Earth was not a snowball state 3 billion years ago, yet the sun was much fainter."

Way said that if we took Earth's atmosphere today and moved it back in time, it would freeze. Clearly, there was something different about Earth then that we still don't understand. Gathering more data from the geologic record might enable researchers to answer that question, put the solution into their model and see whether it works.

These models could also be applied to the study of exoplanets and help future missions, like the James Webb Space Telescope and its successors, in identifying Earth-like planets for closer observation.

"When the time comes in the future, when we can get more data on exoplanets and their atmospheres, we can help better target which planets we want to look at through these models," Way said. "If we think these planets can have liquid water, that's where we want to go."

 

[ilan]

Cornell Astronomy's Facts of the Day
Department of Astronomy | Cornell Center for Astrophysics and Planetary Science

Sagan Planet Walk
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[TD="align: left"]#1 - Saturn's Rings

Saturn's rings are arguably the flattest structure known to man, being some 300,000 km end-to-end but with a vertical thickness of about 10 meters.

#2 - Density of Saturn

Saturn is the only planet in the solar system that would float on water.

#3 - Traveling Time

Traveling at the speed of light it would still take you over 4 years to reach the Sun’s nearest neighbour star.

#4 - Fuel for Thought

The Sun burns 600 million tons of Hydrogen every second.

#5 - Cosmic Popcorn Anyone?

The Cosmic Microwave Background that we detect today started traveling towards us over 13 billion years ago.

#6 - Billions and Billions.....

The Sun is just one of over 100 billion stars in our galaxy, the Milky Way, and the Milky Way is just one of over 100 billion galaxies in the universe.

#7 - Polaris' Retirement

Vega will become our new north star in 12000 years.

#8 - Cosmic Combat

Antares (think anti-Ares) is known as the rival of Mars because Mars passes by this bright red star, "challenging" the planet as it nears.

#9 - Another Horoscope

The constellation Ophiuchus passes through the ecliptic, making it the "13th sign" of the zodiac.

#10 - Not Your Everyday Black Hole

There is a black hole millions of times the mass of the Sun at the center of the Milky Way galaxy.

#11 - Hot Enough to Fry an Egg

Venus, not Mercury, has the hottest surface temperature for a planet due to the Greenhouse Effect.

#12 - Don't Get Dizzy

Some pulsars rotate several hundred times per second.

#13 - The Biggest Loser

You would only weigh about 1/6th of your current weight if you stood on the Moon.

#14 - Drifting Away

Earth is the only planet that has plate tectonics![/TD]
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[ilan]

Researchers validate ancient astronomical structures
Robyn Mills, Physics.org | August 17, 2016

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The great stone circle, Stenness on the Isle of Orkney, is situated in a “reverse” landscape. The project examined the alignments running from the centre of circle through the stones on the circle's perimeter and the stone holes where stones formally stood (as revealed by excavation). This told us that the stone furthest to the right is oriented upon the last glimmer of a southern Moon occurring only every 18.6 years; the second stone is aligned towards the winter solstice sunset and the stone furthest to our left is aligned to the Moon as it sets into its most northern position every 18.6 years. These are astronomical events that could be seen 5000 years ago. Credit: Douglas Scott
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University of Adelaide research has for the first time statistically proven that the earliest standing stone monuments of Britain, the great circles, were constructed specifically in line with the movements of the Sun and Moon, 5000 years ago.

The research, published in the Journal of Archaeological Science: Reports, details the use of innovative 2D and 3-D technology to construct quantitative tests of the patterns of alignment of the standing stones.

"Nobody before this has ever statistically determined that a single stone circle was constructed with astronomical phenomena in mind – it was all supposition," says project leader and University of Adelaide Visiting Research Fellow Dr Gail Higginbottom, who is also a Visiting Research Fellow at the Australian National University.

Examining the oldest great stone circles built in Scotland (Callanish, on the Isle of Lewis, and Stenness, Isle of Orkney ─ both predating Stonehenge's standing stones by about 500 years), the researchers found a great concentration of alignments towards the Sun and Moon at different times of their cycles. And 2000 years later in Scotland, much simpler monuments were still being built that had at least one of the same astronomical alignments found at the great circles.

The stones, however, are not just connected with the Sun and the Moon. The researchers discovered a complex relationship between the alignment of the stones, the surrounding landscape and horizon, and the movements of the Sun and the Moon across that landscape.

"This research is finally proof that the ancient Britons connected the Earth to the sky with their earliest standing stones, and that this practice continued in the same way for 2000 years," says Dr Higginbottom.

Examining sites in detail, it was found that about half the sites were surrounded by one landscape pattern and the other half by the complete reverse.

"These chosen surroundings would have influenced the way the Sun and Moon were seen, particularly in the timing of their rising and setting at special times, like when the Moon appears at its most northerly position on the horizon, which only happens every 18.6 years," Dr Higginbottom says.

"For example, at 50% of the sites, the northern horizon is relatively higher and closer than the southern and the summer solstice Sun rises out of the highest peak in the north. At the other 50% of sites, the southern horizon is higher and closer than the northern, with the winter solstice Sun rising out of these highest horizons.

"These people chose to erect these great stones very precisely within the landscape and in relation to the astronomy they knew. They invested a tremendous amount of effort and work to do so. It tells us about their strong connection with their environment, and how important it must have been to them, for their culture and for their culture's survival."

The research is part of the Western Scotland Megalithic Landscape Project carried out by Dr Higginbottom and Professor Roger Clay, astrophysicist at the University of Adelaide.

 

[Capt.Kangaroo]

Good info as usual.
Thanks ilan.

 

[ilan]

Watching a star explode after 'hibernating'
Ashley Strickland, CNN | Updated 1:52 PM ET, Wed August 17, 2016
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(CNN) Amidst the billions of stars in the Milky Way, astronomers have witnessed the evolution of one as it exploded in what's known as a classical nova after hibernating for years, according to a new study. It is the first time the transition of a white dwarf star with a low and unstable mass-transfer rate to a classical nova eruption has been observed, study author Przemek Mróz said.

"Classical novae attract attention during eruptions, when they are bright and easy to observe," Mróz said. "Because of their unpredictable nature, very little is known about pre-eruption behavior of novae. This is the first case that the evolution of a classical nova can be investigated so precisely with long-term pre- and post-eruption observations."

The classical nova occurred in a binary star system in the Milky Way's Centaurus constellation, 6,300 light-years from Earth.

In a close binary star system where two stars orbit each other, a white dwarf star is paired with a red dwarf star. A classical nova occurs when a white dwarf star gains matter from its secondary star over a period of time, causing a thermonuclear reaction on the surface that eventually erupts in a single visible outburst. This creates a 10,000-fold increase in brightness.

Snapshots of a nova life cycle. Below it is the Milky Way over Las Campanas Observatory.
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Mróz said astronomers observe five to 10 classical novae in the Milky Way each year, but most of them are faint, because they are hidden behind interstellar gas and dust. He cited recent examples like Nova Sagittarii 2015 and Nova Delphini 2013.

But based on long-term observations, this white dwarf star experienced periodic brightening over six years leading up to the explosion. This implies that during that time, a low mass-transfer rate was occurring between the two stars, causing that fluctuation.

Six days before the eruption, there was another fluctuation in brightness. And after the explosion, the mass-transfer rate increased. Now, the system remains bright but is slowly fading, which will continue for a few decades as the process begins again.

 

[ilan]

What do aliens look like? The clue is in evolution
Matthew Wills, The Conversation | August 19, 2016
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The five-eyed fossil Opabinia could have given rise to five-eyed animals today. Credit: Nobu Tamura/wikimedia, CC BY-SA
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Speculating about what aliens look like has kept children, film producers and scientists amused for decades. If they exist, will extra terrestrials turn out to look similar to us, or might they take a form beyond our wildest imaginings? The answer to this question really depends on how we think evolution works at the deepest level.

Hollywood has given us its fair share of humanoid aliens over the years. Initially this was through necessity, as special effects required someone to clamber into a rubber suit. Ironically, now that CGI makes anything possible, aliens sometimes look even more human in order to help the cinema goer make an emotional connection with them – such as in James Cameron's Avatar.

At present, the only life forms we can study are here on Earth. These had a single origin around 3.5 billion years ago, but this common ancestor gave rise to perhaps 20m living species of animals alone. These have bodies organised according to about 30 different body plans in major groups called phyla.

But when animals first diversified some 542m or more years ago in the Cambrian "explosion", there may have been an even greater diversity of fundamental body plans. Consider the five-eyed and trunked Opabina in the image above, or the stalked and almost flower-like Dinomischus alongside our own distant relative, the chordate Pikaia.

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Pikaia – an early chordate, the group to which humans belong. Credit: Nobu Tamura/wikimedia, CC BY-SA
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Rerunning the tape of life

In a famous thought experiment, biologist Stephen Jay Gould asked what might happen if we were to rewind the "tape of life" and rerun it. Gould argued for the importance of chance in evolution: change one small thing early on, and the consequences magnify through time. In the version of history we know, Pikaia (imaged below) or something very like it survived and ultimately gave rise to fishes, amphibians, reptiles, mammals and ultimately ourselves. But what if it had perished? Might some other group have given rise to intelligent beings, and might you now be reading this with five eyes rather than the customary two? If our own origins on Earth really turned on such fine hinges, why should aliens – evolving on different planets – even remotely resemble us?

The answer, according to evolutionary biologist Simon Conway Morris, lies in the phenomenon of evolutionary convergence: the process by which distantly related animals come to closely resemble each other. For example, the similar streamlined shape of dolphins, tuna fish and the extinct ichthyosaurs all evolved independently in response to the same selective pressures for moving efficiently through water at speed.

But what aspects of alien biology might we expect? Carbon-based biochemistry is likely given that carbon forms stable backbone chains, and makes stable but readily breakable bonds with other elements. Other elements, notably silicon and sulphur, make less stable bonds at Earth-like temperatures. Water or some other solvent also seems necessary. For evolution to occur there needs to be some mechanism for storing and replicating information with moderate fidelity, such as DNA, RNA or some analogue. Although the first cells appeared on Earth quite early, multicellular animals took nearly 3 billion more years to evolve. So it may well be that life on other planets could get stuck at the single-celled stage.

On an Earth-like planet it is also likely that radiation from the alien sun or suns would be used in biochemical pathways as a source of energy. For moderately large multicellular primary producers, harnessing light efficiently probably necessitates a light gathering system of leaves and branches. Similar shapes and habits have evolved convergently on Earth, so we might expect "plants" with broadly familiar forms on Earth-like planets.

With few exceptions, animals either eat the primary producers or each other, and there are only so many ways of doing this. Pursuing food often necessitates moving with the mouth first, so the animal has a head and tail end. Teeth and probably jaws evolve to hold and tackle food items. Moving against a hard surface requires specialised structures (such as cilia, a muscular foot or legs) at the interface, so that there is a back and front side. Typically, this also imparts bilateral (left/right) symmetry: indeed, most animals belong to a "super-group" called the Bilateria.

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The giant weta: one of the largest insects. Credit: New Zealand Department of Conservation, CC BY-SA
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Why not giant intelligent "insects"?

But what about the large brained and intelligent creatures that might be capable of crossing interstellar distances? Insects are by far the most species rich group on Earth: why shouldn't aliens look more like them? Unfortunately, having your skeleton on the outside makes growth difficult, and entails periodic shedding and regrowth. On Earth-like planets, all but relatively small terrestrial animals with external skeletons would collapse under their own weight during moulting, and some critical size may be necessary for suitably complex brains.

Relatively large brains, some degree of tool use and problem-solving abilities appear to be correlated on Earth, and have evolved multiple times: in apes, whales, dolphins, dogs, parrots, crows and octopuses. However, the apes have developed tool use to a vastly greater degree. This is at least partly the result of walking on two legs, which frees up the front limbs, and because of the dexterity of our fingers (which may also be a key to the origins of written language).

Ultimately, the jury is out on the extent to which intelligent aliens – if they exist – would resemble us. It may or may not be significant that humans have just two eyes and ears (just enough for stereo vision and hearing), and just two legs (reduced from the initially more stable four). Many other organs also come in pairs as a consequence of our evolutionarily deep-seated – and perhaps inevitable – bilateral symmetry. Still other elements of our body plan are probably nothing more than chance. The fact that we have hands and feet with five digits is a consequence of the fixation on five in our early tetrapod ancestors – close relatives experimented with seven or eight.

Indeed, most species have been subject to an accidental "locking down" during development – making body plans become stereotyped and inflexible with evolutionary time. Untangling the functional from the accidental is one of the big outstanding challenges in evolutionary biology – and may help us better understand how alien lifeforms could differ from us.

The main way we now search for intelligent life in space is by listening for radio or gamma transmissions. These efforts are increasingly being concentrated on star systems with Earth-like planets, as these are believed to be the most likely to harbour life. After all, it is easier to search for "life as we know it" than life as we don't.

 

[ilan]

Weird Object: Red Rectangle Nebula
By Bob Berman, Astonomy Magazine | Published: Friday, December 04, 2015

No. 4: X Marks the Spot of Future Life

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TO ERE IS HUMAN. The Red Rectangle’s red-orange color — called Extended Red Emission, or ERE — had not been seen in the universe until 1975. Astronomers do not completely understand the nebula’s geometric design.
NASA/ESA/Hans Van Winckel (Catholic University of Leuven, Belgium)/Martin Cohen (University of California, Berkeley)
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The Red Rectangle Nebula doesn't merely look modern-art cubist bizarre. Its very light is strange, its composition is food for philosophy, and it remains a hot venue of current research.

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Located in the constellation Monoceros the Unicorn, its central 9th-magnitude binary star was discovered in 1915 by the famous double-star hunter Robert Grant Aitken. Things changed in 1973 when a rocket-borne infrared sky survey discovered the ruddy nebula surrounding the binary, soon labeled HD 44179 after the star’s catalog designation. It took years, and better instrumentation, including studies performed by the Hubble Space Telescope, to fully reveal how odd and intriguing is this dusty gas cloud 2,300 light-years away.

 

[ilan]

The 10 Weirdest Objects in the Universe (Part 1 of 3)
By Sarah Scoles, Discover Magazine | Monday, June 01, 2015

In a place as big as the universe, there's bound to be some weird stuff.
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ESO/SOAR/NASA
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The El Gordo Galaxy Cluster

In a place as big as the universe, there’s bound to be some weird stuff. Here we present the biggest, coldest, hottest, oldest, deadliest, loneliest, darkest, brightest, and more superlatives that the cosmos has to offer, ranging from right next door to the edge of the known universe.

First up, El Gordo. Spanish for “the fat one,” El Gordo is the most massive grouping of galaxies in the distant universe. It contains 3,000,000,000,000,000 (3 million billion, but who’s counting?) times as much mass as the sun.

El Gordo is located 9.7 billion light-years from us, which means it had already grown this large when the universe was just half its current age.

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The Black Widow Pulsar

Pulsar J1311-3430 is a dangerous partner to have.

It weighs as much as two suns but is only as wide as Washington, DC — and it's getting bigger by feeding off its mate, a normal star. The two pirouette around each other every 93 minutes in a deadly, close dance.

The pulsar’s beam strips layers away from the star, which the pulsar then slurps up. That extra material gives the pulsar more energy, making it spin even faster, but leaving its partner depleted. So depleted that someday, nothing will be left and the pulsar will dance with only itself.

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3753 Cruithne

A year on this asteroid (364 days) is almost exactly the same as a year on Earth, meaning they both orbit the sun at about the same distance. Nobody knew about our orbit-twin until 1986, when Duncan Waldron discovered it.

But don’t worry about a collision: Cruithne won’t come closer than 7.5 million miles from Earth. If you want to run a cosmic 5K, though, you can do it across this rock’s surface, which is 3.1 miles in diameter.

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Rogue Planet

Estranged from its parent star and sibling worlds, this rogue planet wanders the universe alone and dawnless, just 100 light-years from where you sit surrounded by your warm social group.

CFBDSIR2149 was likely kicked out of its home solar system during turbulent formative years, when other planets’ orbits established themselves and flung it out into space to fend for itself.

Astronomers estimate that billions of such castaway planets exist.

 

[ilan]

The 10 Weirdest Objects in the Universe (Part 2 of 3)
By Sarah Scoles, Discover Magazine | Monday, June 01, 2015

In a place as big as the universe, there's bound to be some weird stuff.

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Smith's Cloud

If your eyes could see radio waves, Smith’s Cloud would show up 20 times as wide as the full moon in the night sky.

This cloud of hydrogen gas has as much mass as one million stars, but that hydrogen spreads over an area 9,800 light-years long by 3,300 light-years wide.

It looks like a torpedo, and that’s a helpful way to think about it too: It’s headed for our galaxy and will crash into the Milky Way 27 million years from now. That infusion of high-velocity hydrogen could set off fireworks of star formation.

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Galaxy X

Three hundred thousand light-years beyond the Milky Way orbits a satellite galaxy made almost entirely of dark matter and gas — with hardly any stars at all.

Astronomers had suspected its existence for years, but it’s hard to find “dark galaxies” in the darkness of space. In 2009, astronomers detected evidence of "Galaxy X" in the form of ghostly ripples in our own galaxy’s disk. Then, this year, they managed to find four 100-million-year-old stars hiding in this distant clump of dark matter.

This image shows dark matter satellite galaxies around our Milky Way galaxy.

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HD 189733b

This planet’s blue hue might call to mind peaceful oceans and pleasant summer days. But don’t be fooled. It’s a huge gas giant orbiting close to its star, which would makes it a hellish place to live, for a few reasons:

a) No oceans exist ever, b) the temperature rockets as high as 1,700 degrees Fahrenheit, and c) the apparent azure sky actually comes from a deadly weather pattern: rain made of molten glass.

 

[ilan]

The 10 Weirdest Objects in the Universe (Part 3 of 3)
By Sarah Scoles, Discover Magazine | Monday, June 01, 2015

In a place as big as the universe, there's bound to be some weird stuff.

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The Biggest Old Black Hole

When the universe was just 875 million years old (a mere babe), a black hole with the mass of 12 billion suns had already formed.

For reference, the one at the center of the Milky Way, shown here, is just 4 million times the sun’s mass.

Supermassive J0100+2802 sits at the center of an active galaxy, called a quasar, 12.8 billion light-years away. But how could something become so big at such a young age? Astronomers are still working that out.

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R136a1

This star is 256 times as massive as our sun and it shines 7.4 million times as brightly. In other words, it's a behemoth.

Scientists believe stars this colossal can only form when multiple smaller stars merge into each other, forming fiery chimera that live for only a few million years before they burn themselves out.

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The Boomerang Nebula

Pack a jacket before taking the 5,000 light-year trip to the Boomerang Nebula: This is the coldest thing in the universe.

Inside this cloud of gas and dust cast off from a dying sun-sized star, the mercury rises to just -458 degrees Fahrenheit. The cloud is expanding at around 367,000 miles per hour, or 10 times as fast as the fastest man-made object in the universe, the New Horizons spacecraft, is traveling.

That expansion chills the nebula's gas in the same way that ballooning tetrafluoroethane cools your refrigerator.

 

[ilan]

Found you! NASA re-establishes contact with missing spacecraft
By Sheena McKenzie, CNN | Updated 7:05 AM ET, Tue August 23, 2016

An artist rendition of the STEREO spacecraft.

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(CNN) Despite almost two years of silence, NASA never stopped searching for its long lost spacecraft STEREO-B.

This week that determination paid off.

Spacecraft STEREO-A and STEREO-B are studying the sun.
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Lost...

NASA announced Sunday that it had re-established contact with STEREO-B after communications were lost in October 2014.

Contact with the spacecraft -- which works in tandem with a second spacecraft STEREO-A to study the sun -- was lost during a test of one of its timers.

Scientists had been testing the timer when STEREO-B's line of sight and communication to Earth was blocked by the sun.

Meanwhile STEREO-A was unaffected by testing, and continued working normally over the past 22 months.


...and found

STEREO-B was recovered using NASA's Deep Space Network -- an array of giant radio antennas that tracks interplanetary missions.

The positions of STEREO-A, shown in red, and STEREO-B, shown in blue.

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Now contact has been reestablished, the STEREO team will continue monitoring the spacecraft to see what kind of state it's in.

What is the STEREO mission?

Launched in October 2006, the STEREO mission includes two spacecraft -- one ahead of Earth in its orbit, the other behind -- tasked with monitoring the flow of energy and matter from the sun to Earth.

The spacecrafts have already successfully revealed the structure of coronal mass ejections, which are eruptions of matter from the sun so powerful they can disrupt satellites.

 

[ilan]

A new planet in our neighborhood -- how likely is life?
By Don Lincoln | Updated 3:57 PM ET, Wed August 24, 2016

Many are touting this as the astronomy find of the century. - Ilan
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This artist's impression shows the planet Proxima b orbiting the red dwarf star Proxima Centauri, the closest star to our solar system.
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(CNN) Space. The final frontier.

These words inspired many young people to enter science (including me), but I'll bet that's especially true for the team who announced Wednesday that they had found evidence of an Earth-like planet orbiting Proxima Centauri, our closest star. This planet is tentatively called Proxima b.

Scientists working at the European Southern Observatory (ESO), using the La Silla telescope, claim to have discovered the closest exoplanet to Earth.

Exoplanet, of course, means planets orbiting stars other than the Sun. Over 3,000 exoplanets have been discovered by facilities like the ESO and the Kepler orbiting observatory. Most of them are huge planets orbiting very near their star -- Jupiter-like planets heated to temperatures guaranteed to sterilize them of life as we know it.

In recent years, instrumentation has improved to the point that not only can individual planets be found, but even complete solar systems, consisting of many planets. This has been a heady time for planet hunters.

The goal of those inspired by Star Trek's opening words has not been to find planets, but to find planets that are like Earth -- meaning at a temperature on which liquid water could be present and which could theoretically support some form of life. This is what astronomers call "the habitable zone." In addition, we'd like to find a planet that is nearby.

After all, space is huge and human spacecraft using current technology would take tens of thousands of years to get to even this, our closest celestial neighbor. To give a sense of scale, that's longer than human civilization has existed. There are plans under discussion that might reduce travel time to a more manageable duration, even less than a single human lifespan.

So what might this newly discovered planet look like? Well, even though its temperature is thought to be such that liquid water could exist, you shouldn't imagine a lush and verdant world, with lovely blue waters, sandy beaches, lush and green plants, with an excited alien fish occasionally breaching the waters. There are lots of reasons why these are unreasonable expectations.

Setting aside the possibility of life for a moment, Proxima Centauri is a red dwarf, which is the most common type of star in the galaxy. Red dwarfs are much smaller than our Sun. For instance, Proxima Centauri is only about 1.5 times larger than Jupiter. Red dwarfs are very dim. For instance, in the visible spectrum that we use to see, Proxima Centauri gives off 0.0056% as much as light as the Sun.

Most of the light given off by Proxima Centauri is in the infrared region, but even if you compare all of the light emitted by Proxima Centauri in all wavelengths to the amount emitted by the Sun, Proxima Centauri still emits only 0.17% as much light as our own life-giving stellar companion. The star also emits as much x-rays as our own Sun, but Proxima b is much closer to its stellar parent, so the surface receives far more x-rays than Earth.

In addition to being a very dim star, Proxima Centauri is known to be a "flare star," which means the star periodically gives off far more light than usual. During these flares, the x-ray emission can go up tenfold.

Because of the star's small size, a planet in the habitable zone will have to be in a very small orbit, taking under two weeks to complete a single orbit. Any planet that close to a star will be "tidally locked," which means that one face of the planet will constantly face the star. This is just like the Earth and Moon, where we see only one side of the Moon throughout the course of the Month. Proxima Centauri's planetary companion will likely have one side in perpetual daylight, while the other is in perpetual night.

So what about life? Are there any chances that an alien lizard might bask in Proxima Centauri's light or try to find shade under an alien tree? Well, given the instability of the light emitted by the parent star, the answer is likely no, although the real answer to that question is obviously something for observations to answer.

Given the very dim light output of the star, it is likely that any hypothetical plants would have to be black, as black is the most light-absorbent color. "Sunlight" would be precious and evolution would drive alien plants to find ways to collect every bit of energy that falls on them.

Realistically, the prospect of life is improbable. This planet is unlikely to be a haven for people trying to escape the ecological issues of Earth, so we should not view this discovery as a way to ignore our own ecosystem.

Still, the question of extraterrestrial life is a fascinating one, so astronomers are devising techniques to look at the planet's atmosphere. Certain chemicals, like oxygen or methane, cannot exist long in a planet's atmosphere without being constantly replenished by living organisms. Observing them would be strong evidence for life.

So, what's the bottom line? First, the discovery, if confirmed is extremely exciting. The existence of a nearby planet in the habitable zone will perhaps increase the interest in efforts like Project Starshot, which aims to send microprobes to Proxima Centauri with a transit time of about twenty years. It may well be that this discovery will excite an entirely new generation of the prospect "to boldly go where no one has gone before."

 

[ilan]

Today in science: Great Moon Hoax
By Daniela Breitman in Human World | August 25, 2016
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A series of 6 newspaper articles in 1835 about the discovery of life on the moon (including bat-men and unicorns), supposedly made by famous astronomer.

The inhabitants of the moon (Vespertilio homo or bat-men). Credit: Wikimedia Commons
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August 25, 1835. On this date, a New York newspaper, The Sun, published the first article in what’s come to be called The Great Moon Hoax. It was a series of six articles alleging the discovery of life on the moon (including bat-men and unicorns), supposedly made by famous astronomer Sir John Herschel while on a trip to the Cape of Good Hope in South Africa. Richard Adams Locke, a reporter for journal The Sun, is said to have written the article, although he never publicly admitted it.

According to the articles, a Dr. Andrew Grant, Herschel’s (fictitious) companion, was the author. The articles also referred to the Edinburgh Journal of Science, which had been out of commission for some years. Yet, for most readers, the author and the source made the articles seem credible.

The articles were reprinted in papers throughout Europe.

One of the articles said, for example:

It was one of the noble valleys at the foot of this mountain that we found the very superior species of the Vespertilio-homo (bat-men) … They were of infinitely greater personal beauty, and appeared in our eyes scarcely less lovely than the general representations of angels by the more imaginative schools of painters.
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The first article described, among other things, a super-powerful telescope built by Herschel.

The weight of this ponderous lens was 14,826 pounds [Ed. Note: 6,700 kilograms] or nearly seven tons after being polished; and its estimated magnifying power 42,000 times. It was therefore presumed to be capable of representing objects in our lunar satellite of little more than eighteen inches in diameter, providing its focal image of them could be rendered distinct by the transfusion of article light.
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The huge telescope supposedly allowed Herschel to make his fantastic discoveries.

Women and bat-men (under tree) and bipedal beavers (right). Image via Lock Haven University.
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From the very first article, vigilant readers might have guessed it was a hoax. Two scientists from Yale are said to have tried to find the Edinburgh Journal of Science in Yale’s library. An unsuccessful search led them to travel all the way to The Sun’s office in New York, where they were told that the original journal article was still at the printers.

The second article described many other fascinating lunar findings such as beautiful basaltic formations, cliffs, great oceans, and lunar forests. It also described many animals, one similar to a bison, and another that resembles a goat:

The next animal perceived would be classed on Earth as a monster. It was of a bluish lead color, about the size of a goat, with a head and beard like him, and a single horn, slightly inclined forward from the perpendicular. The female was destitute of horn and beard, but had a much longer tail. It was gregarious, and chiefly abounded on the acclivitous glades of the woods. In elegance of symmetry it rivalled the antelope, and like him it seemed an agile sprightly creature, running with great speed, and springing from the green turf with all the unaccountable antics of a young lamb or kitten. This beautiful creature afforded us the most exquisite amusement.
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It was in the last of the series of six that the existence of Vespertilio-homo or bat-men was divulged.

Sir John Herschel at first accepted the story with a sense of humour, saying:

It is too bad my real discoveries here won’t be that exciting.
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The author must have underestimated the gullibility of the people, since the news spread very quickly. Herschel began receiving lots of correspondence regarding his “discoveries” and eventually was not so jolly about it:

I have been pestered from all quarters with that ridiculous hoax about the moon – in English, French, Italian, and German!
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The Sun, which had begun publishing just two years earlier, had a reason for publishing the Great Moon Hoax. It dramatically increased the paper’s popularity.

Also, the author appeared to have been seeking to satirize a scientist and science fiction author of the day, Thomas Dick, who mixed fact with fiction in his novels.

The Great Moon Hoax showed how gullible people can be and may still serve as a reminder that not everything we read is true, even if it seems credible.

Vespertilio-homo. The bat-men of the moon. Credit: Wikimedia Commons, New York Public Library.
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Bottom line: On August 25, 1835, the first of the six Great Moon Hoax articles was published. It described sensational discoveries of the famous astronomer John Herschel, who supposedly observed life on the moon.

 

[ilan]

Black hole breakthrough found on earth (Video)
Source: CNN
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Haifa-based scientist Jeff Steinhauer has simulated a black hole in his laboratory, and it might be the breakthrough that helps celebrated physicist Stephen Hawking win the Nobel Prize. CNN's Ian lee reports.

See Video...

[URL]http://www.cnn.com/videos/tech/2016/08/26/black-hole-breakthrough-lee-pkg.cnn[/URL]

 

[ilan]

Astronomers find a galaxy that's mostly dark matter
Ryan F. Mandelbaum, Astronomy Magazine | Thursday, August 25, 2016

Dragonfly 44 glows only faintly with starlight — but there's a lot more going on behind the scenes.

An image of Dragonfly 99, a faint galaxy dominated by dark matter.
Pieter van Dokkum, Roberto Abraham, Gemini Observatory/AURA
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The hazy oval isn’t glare on your screen; it’s an entire galaxy. Dragonfly 44 weighs about the same as our Milky Way, except it’s 99.99% dark matter and has less than a hundredth the number of stars. Dark matter is stuff that can’t interact with the electromagnetic force (how we mostly experience the world) so we can’t see or touch it.

Scientists can observe its gravitational effects, though, which keep Dragonfly 44’s paltry collection of visible stars from flying apart. There’s around five times as much dark matter as regular matter in the universe, and even our own Milky Way is around 90% dark matter.

Astronomers found Dragonfly 44 with the W. M. Keck Observatory and the Gemini North telescope on Mauna Kea, Hawaii and are publishing their results in The Astrophysical Journal. The team measured Dragonfly 44’s mass by observing its stars’ velocities as they zoomed around the galaxy.

In a press release, scientist Pieter van Dokkum from Yale University pointed out that a galaxy like this one would allow astronomers to better study a huge mass of dark matter with far fewer stars to block the view, or lack thereof.

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I left the image caption as I found it, although I'm fairly certain it is supposed to be Dragonfly 44 instead of Dragonfly 99. - Ilan

 

[ilan]

Russian SETI researchers are pursuing a promising signal
John Wenz, Astronomy.com | Published: Monday, August 29, 2016

It may not be aliens, but something weird was picked up by Russian radio astronomers, who are now digging for answers.

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This 2013 photo shows the RATAN-600 observatory, where a recent microwave transmission has SETI researchers excited.
Wikimedia Commons / ратан 600
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It could be nothing. In the kinds of circles that search for transmissions from alien civilizations, it always is. But nonetheless, Russian researchers in the Search for Extraterrestrial Intelligence (SETI) have something intriguing they're pursuing.
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Let's heavily caveat this. SETI efforts worldwide have had plenty of promising signals. None of them have been confirmed to come from extraterrestrial civilizations. Several have turned out to be from terrestrial sources, and early on, two high profile "What ifs?" lead to the discovery of pulsars and quasars rather than alien megastructures or technologically advanced societies.

Still, there's enough substance to this message that researchers working from the RATAN-600 observatory in Russia are investigating what might have caused it. They've pinpointed a likely star, HD 164595, which is located in the Hercules constellation. It's known to have one planet, a Neptune-sized world in a 40 day orbit. Given that HD 164595 is a Sun-type star, that planet would be too hot for life, but there may be other undiscovered planets in the solar system.

The signal was first detected in May 2015 at the 2.7 cm band, which is around 11 Ghz in the super-high frequency band. That places whatever the signal was in the microwave band. As Lee Berger at Ars Technica points out, there's no known astrophysical source at these wavelengths. There's some chatter that if (BIG if) this is of non-natural origin, it could be slightly to moderately more advanced than our own. "... if it came from an isotropic beacon, it would be of a power possible only for a Kardashev Type II civilization," Paul Gilster at Centauri Dreams writes. "If it were a narrow beam signal focused on our Solar System, it would be of a power available to a Kardashev Type I civilization."

In the Kardashev scaled, Type I civilizations are those somewhat like our own, technology-wise, able to utilize radio signals to reach out and make contact. Type II are more technologically advanced civilizations, the type brought up when we talk about "alien megastructures" like some people have theorized may be around Tabby's Star.

There are other natural reasons that may have caused this. Gilster points to both potential "noise" contamination from other sources could have played a role, as well as a microlensing event which could have boosted the signal from something natural in the background. More telescope time is needed to figure it out and get to the bottom of it. Researchers could then see if it repeats (a much-needed element of SETI research, in order to gather as much data as possible), if there are other unexplored natural scenarios that could have created it, or any other scenario that might be possible.

After that, we can say for sure whether or not it's aliens. But for now let's go with just the words "promising," and hope for the best but prepare for it to be bupkis. Or at least bupkis in the "is it aliens?" department.