Does the Radcliffe wave discovery offer new evidence of a 26-million-year cycle of extinction on Earth?

Posted: January 9, 2020 by oldbrew in Astronomy, Celestial Mechanics, Cycles, History, research

Visualization of the Radcliffe Wave. The wave is marked by red dots. The Sun is represented by a yellow dot to show our proximity to this huge structure. Courtesy of Alyssa Goodman/Harvard University

Scientists have previously reported evidence for a 26-million-year cycle of extinction on Earth, but the idea has remained controversial and unexplained. Now the discovery of the Radcliffe Wave may offer an explanation, but has anyone so far said so?

The team also found the wave interacts with the Sun. It crossed our path about 13 million years ago and will again in another 13 million years. What happened during this encounter is also unknown.

“There was no obvious mass extinction event 13 million years ago, so although we were crossing a sort of minefield back then, it did not leave an obvious mark,” Alves said. “Still, with the advent of more sensitive mass spectrometers, it is likely we will find some sort of mark left on the planet.”

13+13 = 26 (million). Can such a mark be found?
– – –
From the article, ‘Something Appears to Have Collided with the Milky Way and Created a Huge Wave in the Galactic Plane’:

An enormous wave has been discovered in the Milky Way that may have formed as a result of a collision with a massive mystery object—potentially a clump of dark matter—scientists have said.

The “Radcliffe wave” was discovered using data from the European Space Agency’s Gaia satellite. It had previously gone unnoticed because of its extreme size and our proximity to it. From Earth, the wave covers half the sky, making it difficult to see the whole structure. Details of the discovery are published in Nature.

Our galaxy is known as a spiral galaxy. It is largely a flat, rotating disk with arms that circle it. It is about 100,000 light years across, but only around 1,000 light years thick.

Researchers led by João Alves, from the Department of Astrophysics at the University of Vienna and the Radcliffe Institute for Advanced Study at Harvard University, were initially trying to map a structure known as the Gould’s Belt. This is a large band of star-forming regions that the team was hoping to learn more about with Gaia—a mission to create a 3D map of the Milky Way.

In doing so, the team discovered that Gould’s belt is “just a projection effect” of a far larger structure, Alves told Newsweek. “As you can imagine, I was very surprised,” he said.

The Radcliffe wave, they found, was one enormous, long filament. It stretches 9,000 light years in length and 400 in width. It was also found to go 500 light years above and below the mid plane of the galactic disk in a wave-like shape.

The wave, which is made up of interconnected stellar nurseries, is very close to the Milky Way. At its closest point, the Sun is just 500 light years from the wave. “The reason why we didn’t realize the presence of this giant is that we didn’t have the exquisite distance measurements we have today with Gaia and, I think because we are so close to the structure it’s hard to see it.”

What could have produced the wave is not known. However, its amplitude appears to be decreasing over time.

Continued here.

  1. oldbrew says:

    may have formed as a result of a collision with a massive mystery object—potentially a clump of dark matter—scientists have said
    – – –
    a clump of dark matter – is that the best they can come up with?

  2. ivan says:

    oldbrew, they can’t clutch at straws so it has to the usual explanation of dark matter that no one has found.

    Cosmologists must be looking at climatologists and are following their example regarding funding.

  3. JB says:

    Everything unexplained is dark stuff. These idiotic press releases must have a quota behind them.
    A Birkeland current spirals, and viewed from certain angles looks like a wave.Then there’s the mechanical wave effect from a longitudinally moving object; speakers, objects entering a fluid.
    One thing for sure, these characters have no idea whatsoever what happened 13M years ago.

  4. Graeme No.3 says:

    It cannot be long before someone blames Climate Change.
    Since it involves an undetected extinction and a possible one in a long time in the future perhaps they could call it the Thumberg wave?

  5. wyzelli says:

    How can it’s amplitude “appear to be decreasing over time” when it’s only just been discovered?

  6. Tom Abbott says:

    From the article: “The wave, which is made up of interconnected stellar nurseries, is very close to the Milky Way. At its closest point, the Sun is just 500 light years from the wave.”

    “Very close”? From the description it appears to be embedded in the Milky Way. It’s only 500 lightyears from the Sun, which is located in the Milky Way and then they say the wave arcs above and below the Milky Way’s disc by 500 lightyears each way.

    Perhaps it’s just not very precise writing on the part of the author.

    A 3-D look at the Milky Way galaxy would be *very* interesting.

  7. oldbrew says:

    This 3D Map of the Milky Way Is the Best View Yet of Our Galaxy’s Warped, Twisted Shape
    By Charles Q. Choi August 01, 2019

    It’s not flat like we thought.
    = = =
    For context:
    The Milky Way is a huge disk, roughly 100,000 to 120,000 light years across. Its thickness is 1,000 light years throughout most of the disk, but there is a spheroidal bulge at the center of the galaxy that is 12,000 light years in diameter.

  8. oldbrew says:

    Many of Earth’s mass extinctions over the eons have been caused by comet strikes, a new study suggests.

    Over the past 260 million years, cratering rates on Earth have peaked every 26 million years or so, in tune with a previously noted cycle of mass-extinction events, researchers found. Furthermore, five of the six largest impact craters known from the last quarter-billion years — including the 112-mile-wide (180 kilometers) crater associated with the demise of the dinosaurs 65 million years ago — were gouged out at roughly the same time that a mass extinction occurred.

    “The correlation between the formation of these impacts and extinction events over the past 260 million years is striking and suggests a cause-and-effect relationship,” study lead author Michael Rampino, a geologist at New York University, said in a statement. “This cosmic cycle of death and destruction has without a doubt affected the history of life on our planet.”
    [bold added]

  9. Patrick Healy says:

    Come on guys, this m u s t stop.
    Yesterday when I topped my drive it ran over 200 yards along the ground.
    It is known in England as a Paula, or up here in scotland as a Liz.
    Named after two great women athletes, whilst not having film star looks, share as shell could run far.