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Did you see in the news that Canadian astronomers have revealed some details about mysterious signals emanating from a distant galaxy. They don’t really know the exact nature and the origin of the radio waves. But don’t they pick up these signals all of time?

Actually, they don’t get these kinds of signals. This has only been reported once before.The 13 FRBs (fast radio bursts) had a very unusual repeating signal. They were all coming the same source about 1.5 billion light years away. Let’s repeat that – 1.5 billion light years away.

These cosmic puzzles were picked up by the CHIME observatory, located in British Columbia. It has four 100-metre-long, semi-cylindrical antennas, which scan the entire northern sky each day. The telescope only went into operation last year and almost immediately detected the radio bursts.

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At least a quarter of the stars in the Milky Way galaxy have a planet with surface conditions very similar to Earth and the chemistry of life as we know it could develop. With tens of billions of stars in the Milky Way, it is quite likely we are not alone.

Are the aliens trying to contact us? Contact? They may already be visiting.

The solidly unscientific The New Yorker asks “Have Aliens Found Us?” in an interview with a Harvard astronomer about a mysterious interstellar object.

This story starts back in October 2017 when astronomers at the University of Hawaii spotted something strange out there in our solar system. They named it ‘Oumuamua which is the Hawaiian word for a scout or messenger. They described it as “a red and extremely elongated asteroid.”

Big deal. I write about asteroids all the time. Ah, but this was the first interstellar object to be detected within our solar system.

The interview was with Avi Loeb, the chair of Harvard’s astronomy department, who was co-author on a paper about ‘Oumuamua’s “peculiar acceleration.” That is, it wasn’t moving like most asteroids.

Loeb suggested that the object “may be a fully operational probe sent intentionally to Earth’s vicinity by an alien civilization.” Whoa.

Headline #2: He later said that we might communicate with the civilization that sent the probe, and “If these beings are peaceful, we could learn a lot from them.”

I’m a bit suspicious of those scientists who detected ‘Oumuamua said that they saw it “too late” in its journey to photograph it.

There is no photo of the object, but based on how it spins and how its brightness changes, it is assumed to look like a cigar. Or a pancake.

It was the deviation from the expected orbit that interested Loeb and some others.  Where is it getting the extra push in acceleration? Maybe it is the light from the sun. That would happen with a solar sail. But that would mean it would have to be less than a millimeter thick in order for that to work. And that would be mean that someone had made it.  A scout from a technological civilization?

Loeb admits that if some other distant civilization sent out ‘Oumuamua, they might not exist any more. We have sent out lots of stuff from the Voyager spacecrafts to episodes of I Love Lucy and by the time those aliens outside our solar system discover our stuff and figure out how to play that Voyager record and why Lucy always wanted to be in Ricky’s shows, we may not exist.

I hope one of us makes contact before it’s all over.

Sources
cbsnews.com/news/fast-radio-burst…
newyorker.com/news/…oumuamua

Venus and Earth size comparison

Tonight and Friday night are when Venus will be at its brightest. When we see the planet’s daytime/illuminated side is when it is bright and right now is when we see the maximum amount of it.

Venus is the third-brightest celestial body in Earth’s sky (after the Sun and Moon) and is often mistaken for a star.  Tonight you would see it low in the sky with Jupiter, Saturn and Mars above it in a fairly straight line.

When Venus passes between the Earth and Sun (October 26), it will leave the evening sky and move into our morning sky. That passing is known to astronomers as an inferior conjunction of Venus, after which its day side is facing away from us.

Our Moon is always up there and one half is always illuminated by sunlight and the nighttime half is in its own shadow, even though we don’t always see that.

I post a lot about the Moon and I’m hardly alone in being fascinated by it. You may have an astronomical interest in it, or maybe a more Romantic interest. Either way, you probably only think of the view of the Moon from Earth and not the other way.

Right now we are in the last quarter phase when we see half the moon’s day side, and half its night side. I recently discovered that the shadow line dividing day from night is called the lunar terminator.

Here’s another way to view the moon, if only theoretically. If you were on the moon now while it is in its last quarter phase, as it is today, and you were looking back at Earth, you’d see the Earth at its first quarter phase.

Perhaps some day, a lunar-living blogger will post regularly about the phases of the Earth.

 

firts-quarter-earth

As seen from the moon, the terminator on the first quarter Earth depicts sunrise, as the first quarter Earth waxes toward its full phase.

 

GiottoAdoration_of_the_Magi

The comet as the Star of Bethlehem in Giotto’s The Adoration of the Magi, 1305

May 25, 240 B.C.E.: Chinese astronomers Shih Chi and Wen Hsien Thung Khao chronicle the earliest recorded sighting of Halley’s comet at its closest approach to the sun (perihelion).

It wasn’t Halley’s comet because there was no Edmond Halley until the 18th century. Maybe it should be the Cinese Comet. English astronomer Edmond Halley thought that comets observed in 1531, 1607, and 1682 seem very similar and predicted that they were the same comet returning at regular intervals. He predicted it would return in 1758 and it did on Christmas Day. Halley had died by then, but his named was given to it.

It was after his death that astronomers looking back at earlier records based on Halley’s computation decided that the early Chinese record was this same comet. They also decided that a record of the appearance in 164 B.C.E. and one in 87 B.C.E. recorded on Babylonian clay tablets, and a famous 1066 appearance a few months before the Norman Invasion of England.

Mark Twain was born when it appeared in 1835, and in 1909, Twain said: “I came in with Halley’s comet in 1835. It is coming again next year, and I expect to go out with it.” He died on April 21, 1910, one day after the comet reached perihelion.

 

planet9

Planet 9 by Tomruen; background taken from File:ESO – Milky Way.jpg – Own work, CC BY-SA 4.0

This year, a pair of astronomers announced they had found evidence that another, massive planet may exist in the outer solar system. This would be a planet roughly 10 times the mass of Earth. That makes it something like Neptune in size. Big.

It orbits our Sun on a tipped, elliptical path. It never gets closer to the Sun than 30 billion kilometers. That is out there.

When I first read about it, I thought “Maybe this is Planet X.”

Back in the early 1900s, astronomer Percival Lowell starting search for a planet beyond Neptune. For years, he studied the sky from his observatory in Arizona  looking for that planet. He never found it, but his calculations helped other astronomers find Pluto in 1930.

Planet X (also known as Niribu)  is a planet that some people have believed is in our solar system, even though scientists have said it’s not. You might say that believers in Planet X are also “out there” like this new planet. Believers claimed it was not only out there, but possibly inhabited. They claim it is on a huge 3,600-year orbit.

That orbit brought it into our inner solar system enough times to deliver literally Biblical catastrophes to little Earth.

In 2003, a cult following Niribu got some attention in the media until their critical May 15, 2003 date for the appearance of Planet X passed without an appearance.

The Mayan special date of December 21, 2012 (which I covered with some unserious seriousness on this blog) also passed by quietly and Nibiru was slated to crash into Earth that day which was the winter solstice. (Though I still say that the Mayan calendar was misinterpreted and was never meant to indicate the “end of the world.”)

One of the astronomers who discovered this new planet was Mike Brown who was also one of the party-poopers who helped get Pluto demoted to less than planet status. (PlutoKiller‘s team discovered Eris, a large object roughly the same size as Pluto and that discovery eventually led to the International Astronomical Union’s demotion.

Of course, this new planet is not going to be demoted, because it is very big. It would become the new ninth planet. It is a tricky call on this one because to say the planet was “discovered” when no one has seen it (even in a big telescope) is a bit of a reach.  Like other things in science, including most things that Albert Einstein was famous for, we have some evidence that something exists or is possible, but we don’t actually have it. Think about all that searching for the Higgs boson particle which was “confirmed” in 2013.

People haven’t given up on Planet X or Niribu. There are still “predictions” of disaster connected to it. And NASA has checked in to say that although their WISE survey found thousands of new stars, but no Planet X – but maybe a “Planet 9.” (Not to be confused with the wonderfully, terrible film Plan 9 From Outer Space)

 

A paper by a team of astronomers has folks talking about aliens – even though the paper never really discusses aliens. I find it intriguing, but, for me, the real thought experiment is something I will conclude with here.

These astronomers found an odd star that behaves in a way that is difficult to explain. The star is boringly called KIC 8462852. (Astronomers need to work on their naming conventions. “Death Star” would have been much better.) NASA’s Kepler mission has found this and many other stars. The brightness of this star dips, as do many stars. There is a slight dimming when a star has planets that orbit it and pass directly in front of the star as seen from Earth or the telescope. That is called a transit. The brightness dips about one percent or less. It is a way that exoplanets have been found. The dip will be periodic, repeating every few days, weeks, or months, depending on the size of the planet’s orbit.

KIC 8462852 is bigger, hotter and brighter than our Sun, but too faint to see with the naked eye. The dips in the light from it are not periodic but arbitrary and sometimes drop by 15 or 22 percent.

That’s not from a planet. Even a big Jupiter-sized one would only knock out that 1 percent of the starlight. But whatever it is, it’s big – maybe half the size of the star. I remember from elementary science class that you could fit more than a thousand Earths inside the Sun. Very big something out there.

The scientists probably suspected the furor and buzz this would get in the press and included obvious causes that can be eliminated. It’s not a flaw in the telescope, or debris from a planetary collision or a series of comets orbiting the star.

aliensWhat explanations remain?

Physicist Freeman Dyson popularized the Dyson Sphere (not a fancy rolling ball vacuum cleaner) which speculated that we (or some aliens) might build thousands of gigantic solar panels and put them in orbit around their Sun to power the planet. This could expand until you had a gigantic sphere that completely enclosed the star.

It sounds like something from sci-fi (and it was in an episode of Star Trek: The Next Generation). This sphere would be dark in visible light but emit a lot of infrared light.

Have we observed an advanced alien civilization building a huge solar collectors?

An article published in The Atlantic by Wright and Boyajian is what has Internet-popularized this topic.

This is the dream of those who use radio telescopes to look for signals from out there and SETI (Search for Extraterrestrial Intelligence) and all the alien watchers and those who hope to make contact. (Yeah, watch the movie or read the book by that name.)

Here’s my big takeaway. The light we are seeing is 1500 light years away. If they were building 1500 years ago, I suspect that they are done by now. And if they are watching us, they are seeing us in about 505 A.D. We certainly look like a bunch of dopes who could easily be conquered, on a nice planet with water and resources. Do we really want to find them or have them find us?

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