New data confirms lack of dark matter in one galaxy
The uncertainty of science: Astronomers have strengthened their evidence that one particular nearby galaxy is completely devoid of dark matter, a situation that challenges the existing theories about dark matter which suggest it comprises the bulk of all matter in the universe.
The astronomers had made their first claim that this galaxy, NGC 1052-DF2, lacked dark matter back in 2018, a claim that was strongly disputed by others.
The claim however would only hold up if the galaxy’s distance from Earth was as far away as they then estimated, 65 million light years (not the 42 million light years estimated by others). If it were closer, as other scientists insisted, then NCC 1052-DF2 likely did have dark matter, and the theorists could sleep at night knowing that their theory about dark matter was right.
To test their claim, the astronomers used the Hubble Space Telescope to get a better, more tightly constrained estimate of the distance, and discovered the galaxy was even farther away then previously believed.
Team member Zili Shen, from Yale University, says that the new Hubble observations help them confirm that DF2 is not only farther from Earth than some astronomers suggest, but also slightly more distant than the team’s original estimates.
The new distance estimate is that DF2 is 72 million light-years as opposed to 42 million light-years, as reported by other independent teams. This places the galaxy farther than the original Hubble 2018 estimate of 65 light-years distance.
So, does this discovery invalidate the theories about dark matter? Yes and no. The theories now have to account for the existence of galaxies with no dark matter. Previously it was assumed that dark matter was to be found as blobs at the locations of all galaxies. Apparently it is not.
However, the lack of dark matter at this one galaxy does not prove that dark matter is not real. As noted by the lead astronomer in this research,
“In our 2018 paper, we suggested that if you have a galaxy without dark matter, and other similar galaxies seem to have it, that means that dark matter is actually real and it exists,” van Dokkum said. “It’s not a mirage.
Ah, the uncertainty of science. Isn’t it wonderful?
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon. from any other book seller, or direct from my ebook publisher, ebookit.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
The uncertainty of science: Astronomers have strengthened their evidence that one particular nearby galaxy is completely devoid of dark matter, a situation that challenges the existing theories about dark matter which suggest it comprises the bulk of all matter in the universe.
The astronomers had made their first claim that this galaxy, NGC 1052-DF2, lacked dark matter back in 2018, a claim that was strongly disputed by others.
The claim however would only hold up if the galaxy’s distance from Earth was as far away as they then estimated, 65 million light years (not the 42 million light years estimated by others). If it were closer, as other scientists insisted, then NCC 1052-DF2 likely did have dark matter, and the theorists could sleep at night knowing that their theory about dark matter was right.
To test their claim, the astronomers used the Hubble Space Telescope to get a better, more tightly constrained estimate of the distance, and discovered the galaxy was even farther away then previously believed.
Team member Zili Shen, from Yale University, says that the new Hubble observations help them confirm that DF2 is not only farther from Earth than some astronomers suggest, but also slightly more distant than the team’s original estimates.
The new distance estimate is that DF2 is 72 million light-years as opposed to 42 million light-years, as reported by other independent teams. This places the galaxy farther than the original Hubble 2018 estimate of 65 light-years distance.
So, does this discovery invalidate the theories about dark matter? Yes and no. The theories now have to account for the existence of galaxies with no dark matter. Previously it was assumed that dark matter was to be found as blobs at the locations of all galaxies. Apparently it is not.
However, the lack of dark matter at this one galaxy does not prove that dark matter is not real. As noted by the lead astronomer in this research,
“In our 2018 paper, we suggested that if you have a galaxy without dark matter, and other similar galaxies seem to have it, that means that dark matter is actually real and it exists,” van Dokkum said. “It’s not a mirage.
Ah, the uncertainty of science. Isn’t it wonderful?
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon. from any other book seller, or direct from my ebook publisher, ebookit. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
I always thought dark matter was a fudge. Sort of like the classic New Yorker cartoon: https://pmpaspeakingofprecision.files.wordpress.com/2015/03/then-a-miracle-occurs-logic-1050×700.jpg
You have results you can’t explain so you create a fudge to resolve it.
brightdark. Yup.
THE SCIENCE! is settles we can’t have people doing science. I love reminding my students about how it wasn’t until 1950’s that plate tectonics was widely expected despite the theory being out there for decades before and the data really not changing that much in the next 50 years. The reason it took almost 50 years to get into the universities you needed the old guard invested in the the old theory to almost all leave before our current understanding to take over.
If that is what its going to take to change understanding I expect it will be the 2070’s before dark matter really starts to lose its base of support.
Dark Matter: The Situation has Changed
Sabine Hossenfelder (May 2021)
https://youtu.be/4_qJptwikRc
11:49
From the article: “Nevertheless, van Dokkum thinks finding a galaxy lacking dark matter tells astronomers something about the invisible substance. “In our 2018 paper, we suggested that if you have a galaxy without dark matter, and other similar galaxies seem to have it, that means that dark matter is actually real and it exists,” van Dokkum said. “It’s not a mirage.”
I’m probably being cute but I think it’s hard to prove something exists by it’s absence. Especially when it’s supposed to be “invisible” to start with.
Miracle occurs here, I like it.
It’s like when I tell people; mythical greenhouse absorbing and radiating heat back to the heat source violates the “second law of thermodynamics”, and is therefore impossible. They tell me I underestimate the power of belief and faith. “It is real because it transcends the science…” To which I ask them to demonstrate their faith, to break the law of gravity by lifting themselves up by their shoelaces or bootstraps.
The science is settled! Just ask Mr. science Dr. Fauci, but only him because if you ask anybody else you will get a completely different answer. Matter of fact, he himself will give you a different answer every time you ask him about the settled science. Like dark matter, the understanding changes from person to person. I like Wayne’s gravitational solution, demonstrated in his video the best. Solutions based on observation.
Background microwave radiation can be explained and generated by many different natural phenomenon. As for dark matter that does not interact with our universe, except where it wants to, is not a valid explanation. It’s a leap of faith in an unseen invisible world where the dragons, unicorns, fairies and leprechauns live.
Although, there are some unanswered gravity issues that might be the key to solving the dark matter problem… Or just confuse it.
The observation of tides that occur on this planet, particularly during the new moon. With all the gravity sources of the sun, moon and earth in alignment, what causes the bulge rising against gravity on the far side of the planet? Antigravity?
I know the books explains it as “inertia”, which is another way of saying “miracle goes here”.
logic and mathematical expectations would conclude the “combination” of all three gravity sources to cause an “extremely low tide”, with the water level on the sides of the planet at right angles to the gravity source being neutral/sea level. No!
The ocean drops below sea level/low Tide, at right angles to the gravity affect (just as magnetism happens at right angles to the flow of electricity in a wire)
If gravity increases, expressing itself as a lower than neutral water line, it should be able to be measured rising and falling every six hours as the earth rotates. A check of barometric pressure, with no storms, may be sufficient to show the discrepancy with the gravity induced tides.
If the gravity anomaly is applied to the galaxy’s as a whole, it may answer questions… Or not.
The best part is, if anti gravity can occur in nature, humans can find out why and replicate it…
Hey !
Where did it go ?
It was here awhile ago … was it not ?
…here dark dark ….
…. come out come out from ….. hmmm ?
crum. no dark dark … for now ….
Sturgill Simpson –
“Turtles All The Way Down” (2014)
https://youtu.be/6gBV-Nzq7Pg
3:05
@ Max, some of the comment rests on extremely shaky ground… I’m not sure that the tides on earth are not pretty much understood. And I’m afraid I almost never click on any YouTube link. Give me a reference to an academic paper and I will have a look… The biggest platform in human existence for crackpots and bull crap… Not so much. ( I don’t mind a nice music video tho…)
From their inception, dark matter and dark energy were created as “place holders” until they could be explained by a grand unified model. … That never happened, instead, scientists idea of a grand unified model started to bend towards the idea that they were correct, and their theory should incorporate a gravity mass that is undetectable, and an energy source that is unexplainable.. I personally, as an armchair physicist, think that this “dark” stuff is dark because we have something wrong. It’s not even there… And never has been. We need another Einstein to jump this gap in our understanding.
It will probably be IE… And I for one welcome our robot overlords if they can solve the riddle!
max wrote;”The observation of tides that occur on this planet, particularly during the new moon. With all the gravity sources of the sun, moon and earth in alignment, what causes the bulge rising against gravity on the far side of the planet? Antigravity?”
Lee Stevenson is correct: the tides on Earth are well understood.
The Moon and the Sun pull on the near side of the Earth more than on the center of the Earth. This means that the near side “rises” up relative to the center, causing a tide on the near side. They pull on the center of the Earth more than on the far side of the Earth. This means that the far side “falls away” relative to the center, again causing a tide on the far side. No magic needed, no antigravity needed.
Brian Stelter (this….is CNN)
“I, for one, welcome our new insect overlords”
https://youtu.be/8lcUHQYhPTE
0:48
Whether Einstein or the Standard Model get tweaked, the fact that we can only find 1 part in 20 of the Universe ought to at least be a bit humbling.
“Gravity and inertia act in opposition on the Earth’s oceans, creating tidal bulges on opposite sites of the planet. On the “near” side of the Earth (the side facing the moon), the gravitational force of the moon pulls the ocean’s waters toward it, creating one bulge. On the far side of the Earth, inertia dominates, creating a second bulge.”
https://oceanservice.noaa.gov/education/tutorial_tides/tides03_gravity.html
“Over the rest of the globe gravity and inertia are in relative balance. Because water is fluid, the two bulges stay aligned with the moon as the Earth rotates”
The sun has slightly less affect, about 46%. When the moon is at 1/4 or 3/4, The sun and moon cancel each other out creating very little tide. (neap tides)
“The moon is a major influence on the Earth’s tides, but the sun also generates considerable tidal forces. Solar tides are about “half as large” (other articles express it as 1/3 as compared to the moons 2/3 influence) as lunar tides and are expressed as a variation of lunar tidal patterns, not as a separate set of tides. When the sun, moon, and Earth are in alignment (at the time of the new or full moon), the solar tide has an additive effect on the lunar tide, creating extra-high high tides, and very low, low tides”
So inertia causes the bulge on the far side of the earth during new moon… inertia as explained in one article is the water wanting to go in a straight line while the earth curves around the sun and the moon. At full Moon wouldn’t that inertia be combined with the pull of the moon to create a much larger tide? During full moon and new moon the tides are at their strongest but are about equal on both sides of the earth, the difference between the two is 3%… That’s it. Because the nightside part of our planet is further away from the Sun than the noon side, The gravitational effect is slightly less… That accounts for the 3% difference.
Edward said;
” They pull on the center of the Earth more than on the far side of the Earth. This means that the far side “falls away” relative to the center, again causing a tide on the far side. No magic needed, no antigravity needed”
When you say “falls away”, I say “falls up” A contradiction. Falling up against earths gravity.
My argument is that it should be, because gravity has only one direction, “very LOW tide” that should be occurring (minus the 3%) on the Darkside of the planet during the new moon. Is there something else happening? A obvious but undeclared force in play?
Particularly when you factor in that low tides is as much below sea level as high tides are above sea level. Inertia again?
I can except a drop in of a few inches as the high tides remove volume, displacement of water someplace, but so much water removed below gravitational Sea level where the gravity affect is neutral, doesn’t hold muster with me.
Perhaps I should put a weight on a sensitive scale with a Time-lapse Camera to show if the weight goes up and down with the rotation of the planet during new moon. (i’m not aware of any gravitational effect inside the space station as it passes between the earth and the moon… Does objects suddenly migrate across the cabin?)
We discussed major earthquakes occurring at low Tide during the new and full moon, another example of an unknown force increasing stress is at 90° to the gravitational force. (graviton enhancement?)
I can’t prove anything, these are just thoughts that don’t make sense to me. Apparently because there are so many search results, others have thought of it too. I’ve been unsuccessful at finding an explanation, just variations of the same inertia.
I should also point out that the tides are higher near the Arctic Circle like the cook inlet near Anchorage or the circular Bay in northern Canada. Strange.
I Remember a mechanical engineer in college Who explained how there was more gravity the further north you go. when he drove Long haul truck of parts for Fords made in Canada, truck weighed in at 50,000 pounds at the factory, the maximum amount which was checked at the waystation going into the United States at just under 50,000. By the time he arrived in Mexico where the parts were assembled, the truck weighed a considerable amount less.
I know, it’s possible this can be contributed to the centrifugal force of the earth spinning… or it could be that the poles are always at 90° to the gravity affect creating a “low tide” affect continuously.
That may also explain why many galaxies are flat.
I’ll have a day off soon, I will look into it deeper then.
Some of the difference may be due to the Earth’s equatorial bulge making the surface at the poles closer to the center and hence GMm/r^2 says more gravity there
Max wrote: “When you say ‘falls away’, I say ‘falls up’ A contradiction. Falling up against earths gravity.”
That is what they mean by inertia.
The Moon and the Sun pull on the earth, causing the Earth to fall toward them as though in orbit around them. The Moon and the Sun pull on the near side of the Earth more than on the center of the Earth.
The acceleration of the near side of the Earth is greater than the center of the Earth, the inertia of which leaves it a meter or so farther behind. This means that the near side “rises” up relative to the center, causing a tide on the near side. They pull on the center of the Earth more than on the far side of the Earth. The acceleration of the center side of the Earth is greater than the far side of the Earth, the inertia of which leaves it a meter or so farther behind. This means that the far side “falls away” relative to the center, again causing a tide on the far side. No gravity in any other direction needed.