Vera Rubin, the American astronomer who confirmed the existence of dark matter, died at the age of 88 years.

Vera Rubin, the American astronomer who confirmed the existence of dark matter,  died at the age of 88 years, on the December 25, 2016.

First, the existence of this material was proposed by astrophysicist Fritz Zwicky in the 30s, but Rubin is one that confirmed his hypothesis. The observations made by scientists in the 70s were met with skepticism, but were confirmed in the decades that followed.

BBC - Universe - Vera Rubin photo: bbc

Reaching for the Stars - Vera Rubin photo: vq.vassar.edu

First, the existence of this material was proposed by astrophysicist Fritz Zwicky in the 30s, but Rubin is one that confirmed his hypothesis. The observations made by scientists in the 70s were met with skepticism, but were confirmed in the decades that followed.

Dark matter is invisible and impossible to detect because it does not absorb or emit light, so even until this day no one knows exactly what it consists of.

Proof of its existence came when astronomers began to weigh galaxies and noticed that they are much heavier than was originally thought. Vera Rubin worked with a new spectrographs to determine the stars from the edge moves faster than was observed since the first calculations use only the visible matter. It is argued that this difference in speed is due to dark matter.

Rubin's discovery was presented in 1980 in an influential paper that supported the idea that dark matter is an essential mystery that astronomers need to solve.


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• The First Stars in the Universe could provide clues about Dark Matter

• Dark Energy vs. Dark Matter

• Astronomers issued a shocking theory about the universe: 'The Universe is Flat!'

• The universe: Reading the future from the distant past

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Chandra X-Ray Observatory Recently discovered new SPT0346-52. Galaxy is undergoing an extraordinary boom of stellar construction, clues to universe’s evolution and big bang

The distorted galaxy in the simulation results from a collision between two galaxies, followed by them merging. Astronomers think such a merger could be the reason why SPT0346-52 is having such a boom of stellar construction. Once the two galaxies collide, gas near the center of the merged galaxy (shown as the bright region in the center of the simulation) is compressed, producing a burst of new stars. The composite inset shows X-ray data from Chandra (blue), short wavelength infrared data from Hubble (green), infrared light from Spitzer (red) at longer wavelengths, and infrared data from ALMA (magenta) at even longer wavelengths. (The light from SPT0346-52 is distorted and magnified by the gravity of an intervening galaxy, producing three elongated images in the ALMA data located near the center of the image. SPT0346-52 is not visible in the Hubble or Spitzer data, but the intervening galaxy causing the gravitational lensing is detected.) There is no blue at the center of the image, showing that Chandra did not detect any X-rays that could have signaled the presence of a growing black hole. Credit: Image courtesy of CXC Press Office.

A recently discovered galaxy is undergoing an extraordinary boom of stellar construction, revealed by a group of astronomers led by University of Florida graduate student Jingzhe Ma using NASA's Chandra X-Ray Observatory.

The galaxy known as SPT 0346‐52 is 12.7 billion light years from Earth, seen at a critical stage in the evolution of galaxies about a billion years after the Big Bang.

Chandra Overview NASA

Astronomers first discovered SPT 0346‐52 with the National Science Foundation's South Pole Telescope, then observed it with space and ground-based telescopes. Data from the NSF/ESO Atacama Large Millimeter/submillimeter Array in Chile revealed extremely bright infrared emission, suggesting that the galaxy is undergoing a tremendous burst of star birth.

South Pole Telescope - Wikipedia

SPT 0346-52 is part of a population of strong gravitationally-lensed galaxies photo: discovered Sci-News.com

However, an alternative explanation remained: Was much of the infrared emission instead caused by a rapidly growing supermassive black hole at the galaxy's center? Gas falling towards the black hole would become much hotter and brighter, causing surrounding dust and gas to glow in infrared light. To explore this possibility, researchers used NASA's Chandra X‐ray Observatory and CSIRO's Australia Telescope Compact Array, a radio telescope.

No X‐rays or radio waves were detected, so astronomers were able to rule out a black hole being responsible for most of the bright infrared light.

About Australia Telescope Compact Array - CSIRO

"We now know that this galaxy doesn't have a gorging black hole, but instead is shining brightly with the light from newborn stars," Ma said. "This gives us information about how galaxies and the stars within them evolve during some of the earliest times in the universe."

Stars are forming at a rate of about 4,500 times the mass of the Sun every year in SPT0346-52, one of the highest rates seen in a galaxy. This is in contrast to a galaxy like the Milky Way that only forms about one solar mass of new stars per year.

"Astronomers call galaxies with lots of star formation 'starburst' galaxies," said UF astronomy professor Anthony Gonzalez, who co-authored the study. "That term doesn't seem to do this galaxy justice, so we are calling it a 'hyper-starburst' galaxy."

The high rate of star formation implies that a large reservoir of cool gas in the galaxy is being converted into stars with unusually high efficiency.

Astronomers hope that by studying more galaxies like SPT0346‐52 they will learn more about the formation and growth of massive galaxies and the supermassive black holes at their centers.

"For decades, astronomers have known that supermassive black holes and the stars in their host galaxies grow together," said co-author Joaquin Vieira of the University of Illinois at Urbana‐Champaign. "Exactly why they do this is still a mystery. SPT0346-52 is interesting because we have observed an incredible burst of stars forming, and yet found no evidence for a growing supermassive black hole. We would really like to study this galaxy in greater detail and understand what triggered the star formation and how that affects the growth of the black hole."

Joaquin Vieira Wins Sloan Fellowship Astronomy at Illinois

SPT0346‐52 is part of a population of strong gravitationally-lensed galaxies discovered with the SPT. It appears about six times brighter than it would without gravitational lensing, which enables astronomers to see more details than would otherwise be possible.



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• It was created the most complex map of the Milky Way . It shows that our galaxy is much more extensive than previously thought

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It was created the most complex map of the Milky Way . It shows that our galaxy is much more extensive than previously thought

Milky Way  (Foto:spaceandintelligence.com) 

Researchers say they underestimated the number of stars existing within our galaxy.

European Space Agency released the most detailed map to date of the Milky Way. The digital representation depicting the positions of no less than 1.142 billion stars, is the first product of Gaia space observatory, launched three years ago. Among the identified cosmic objects there were about 400 million stars unknown, which means that our galaxy is much more extensive than previously thought in the moment.

,, This map released today the extraordinary density of the stars studied by Gaia indicates and confirms that space observatory has collected valuable information in its first year of activity. Although current data are preliminary, we will do our best to put them to the community of astronomers to use them as soon as possible, "says Timo Prussia, a researcher involved in the project Gaia.

Map presented by the European Space Agency experts is the result of the cumulative effort of not less than 450 researchers. Comparing observations with the help of Gaia observer to those shown in the Hipparcos and Tycho catalogs-2, scientists have been able to estimate distances and movements carried about 2 million stars. The result: the most comprehensive picture of the movement of the stars obtained so far.

Map Milky Way obtained by European astronomers (Photo: sciencealert.com/ESA/Gaia/DPAC)

Gaia Space Observatory is located about 1.5 million kilometers from Earth and is equipped with a 1 miliiard pixels capable of measuring the diameter of a human hair from a distance of 1,000 kilometers. Vehicle mission will last nearly 5 years and aims at mapping the Milky Way, which astronomers assume that accommodates no less than 100 billion stars.

Although experts are confident that the Centre will not be able to analyze these cosmic objects over 5 years, they say, for now, the result is very good, given that Gaia has begun to map the proper since July 2014.


,, It appears we underestimated the number of stars. We think there are about 2-2.5 billion, "said van Leeuwen Floor, researcher at Cambridge University.

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• The Milky Way's Halo Spins With The Galaxy
• Dark Energy vs. Dark Matter
• 4,000 confirmed exoplanets similar to Earth
• The universe: Reading the future from the distant past

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Dark Energy vs. Dark Matter: What The Universe is Made Of

Dark Energy vs. Dark Matter

While dark energy repels, dark matter attracts. And dark matter’s influence shows up even in individual galaxies, while dark energy acts only on the scale of the entire universe

Our universe may contain 100 billion galaxies, each with billions of stars, great clouds of gas and dust, and perhaps scads of planets and moons and other little bits of cosmic flotsam. The stars produce an abundance of energy, from radio waves to X-rays, which streak across the universe at the speed of light.

Yet everything that we can see is like the tip of the cosmic iceberg — it accounts for only about four percent of the total mass and energy in the universe.

About one-quarter of the universe consists of dark matter, which releases no detectable energy, but which exerts a gravitational pull on all the visible matter in the universe.

Because of the names, it’s easy to confuse dark matter and dark energy. And while they may be related, their effects are quite different. In brief, dark matter attracts, dark energy repels. While dark matter pulls matter inward, dark energy pushes it outward. Also, while dark energy shows itself only on the largest cosmic scale, dark matter exerts its influence on individual galaxies as well as the universe at large.

In fact, astronomers discovered dark matter while studying the outer regions of our galaxy, the Milky Way.


A ring of possible dark matter highlights this Hubble Space Telescope image of a distant galaxy cluster. [NASA/ESA/M.J. Jee/H. Ford (Johns Hopkins)]

The Milky Way is shaped like a disk that is about 100,000 light-years across. The stars in this disk all orbit the center of the galaxy. The laws of gravity say that the stars that are closest to the center of the galaxy — which is also its center of mass — should move faster than those out on the galaxy’s edge.

Yet when astronomers measured stars all across the galaxy, they found that they all orbit the center of the galaxy at about the same speed. This suggests that something outside the galaxy’s disk is tugging at the stars: dark matter.

Calculations show that a vast "halo" of dark matter surrounds the Milky Way. The halo may be 10 times as massive as the bright disk, so it exerts a strong gravitational pull.

The same effect is seen in many other galaxies. And clusters of galaxies show exactly the same thing — their gravity is far stronger than the combined pull of all their visible stars and gas clouds.

Scientists shed light on mystery of dark matter HeritageDaily

Are dark matter and dark energy related? No one knows. The leading theory says that dark matter consists of a type of subatomic particle that has not yet been detected, although upcoming experiments with the world’s most powerful particle accelerator may reveal its presence. Dark energy may have its own particle, although there is little evidence of one.

Instead, dark matter and dark energy appear to be competing forces in our universe. The only things they seem to have in common is that both were forged in the Big Bang, and both remain mysterious.

Other articles on the same theme:

• New Theory Of Gravity Tries To Explain Dark Matter

• What form does the atomic nucleus? New discovery may explain the mysteries of the Universe.

• A new theory on the Creation of the Universe, disprove the Big Bang

• Vera Rubin, the American astronomer who confirmed the existence of dark matter, died at the age of 88 years.

Source: hetdex