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Chinese Astronomers Discover 591 High Velocity Stars – 43 of Them Can Even Escape From the Galaxy

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591 High Velocity Stars

591 high velocity stars’ positions and orbits. Credit: Kong Xiao of NAOC

A research team, led by astronomers from National Astronomical Observatories of Chinese Academy of Sciences (NAOC), has discovered 591 high velocity stars from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) and Gaia, and 43 of them can even escape from the Galaxy. After the first high velocity star was discovered in 2005, there are in total of over 550 high velocity stars have been found with multiple telescopes in 15 years. “The 591 high velocity stars discovered this time doubled the total number of high velocity stars previously discovered, bringing the total number exceeding 1000,” said Dr. Yin-Bi Li, the lead author of the research.

High velocity stars are kind of fast-moving stars, and they can even escape from the Galaxy. “Though rare in the Milky Way, high velocity stars, with unique kinematics, can provide deep insight into a wide range of Galactic science, from the central supermassive black hole to distant Galactic halo,” said Prof. You-Jun Lu from NAOC, co-author of this research.

As mentioned above, these high velocity stars were discovered with LAMOST and Gaia. LAMOST is the largest optical telescope in China, which has the highest spectral acquisition rate in the world and can observe about 4,000 celestial targets in one single exposure, and it began the regular surveys in 2012, which established the largest spectra database in the world. Gaia is a space-based mission in the science program of the European Space Agency (ESA) launched in 2013, and it provided astrometric parameters for over 1.3 billion sources, which is the largest database of astrometric parameters. “The two massive databases provide us unprecedented opportunity to find more high velocity stars, and we did it,” said Prof. A-Li Luo from NAOC, co-author of this research.

From the kinematics and chemistries, research team found that the 591 high velocity stars are inner halo stars. “Their low metallicities indicate that the bulk of the stellar halo formed as a consequence of the accretion and tidal disruption of dwarf galaxies,” said Prof. Gang Zhao from NAOC, co-author of this research.

The discovery of these high velocity stars tells us that the combination of multiple large surveys in the future will help us to discover more high velocity stars and other rare stars, which will be used to study the unsolved mystery about our Galaxy.

This work has been recently published online in The Astrophysical Journal Supplement Series.

Reference: “591 High-velocity Stars in the Galactic Halo Selected from LAMOST DR7 and Gaia DR2” by Yin-Bi Li, A-Li Luo, You-Jun Lu, Xue-Sen Zhang, Jiao Li, Rui Wang, Fang Zuo, Maosheng Xiang, Yuan-Sen Ting, Tommaso Marchetti, Shuo Li, You-Fen Wang, Shuo Zhang, Kohei Hattori, Yong-Heng Zhao, Hua-Wei Zhang and Gang Zhao, 17 December 2020, The Astrophysical Journal.
DOI: 10.3847/1538-4365/abc16e

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Hearing the dead person? Here’s what research says – Tech Explorist

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Why some people and not others say they receive communications from ‘the dead’?

This is horrifying. Right?

But why this happens?

A new study by Durham University explains the reason. The study found that spiritualist mediums might be more prone to immersive mental activities and unusual auditory experiences early in life.

Spiritualism is a religious movement dependent on the possibility that human spirits keep on existing after death and speak with the living through a medium or psychic.

A medium that hears the dead person is believed to be experiencing clairaudient communications instead of clairvoyant (“seeing”) or clairsentient (“feeling” or “sensing”) communications.

The study involved 65 clairaudient spiritualist mediums from the Spiritualists’ National Union and 143 members of the general population.

Spiritualist mediums completed an online questionnaire assessing the timing, nature, and frequency of their auditory (clairaudient) spiritual communications – including scales measuring paranormal beliefs, absorption, hallucination-proneness, and aspects identity. These measures were compared to a general population group.

They found that these spiritualists have a strong leaning towards absorption – a trait linked to immersion in mental or imaginative activities and altered states of consciousness.

Eighteen percent revealed having clairaudient experiences ‘for as far back as they could recall’, and 71 percent had not experienced Spiritualism as a religious movement preceding their first experience.

Numerous who experience hearing dead voices experience spiritualist beliefs while looking for the meaning behind, or heavenly significance of, their own and unusual experiences.

Spiritualists tend to report unusual auditory experiences that are positive, start early in life and are often then able to control.

Understanding how these develop is important in helping us learn more about distressing or non-controllable experiences of hearing voices and how to support those whose voices are linked to psychosis or other mental health problems.

Journal Reference:
  1. Adam Powell et al. When spirits speak: absorption, attribution, and identity among spiritualists who report “clairaudient” voice experiences. DOI: 10.1080/13674676.2020.1793310

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Three more COVID-19 cases at GRT – KitchenerToday.com

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Grand River Transit is confirming three more COVID cases.

All the affected employees are bus drivers.

Two of them last worked on January 15, while the third was last on the job on Jan. 11.

GRT points out all three are now self-isolating at home.

So far in Janaury, nine employees have tested positive for the virus.

Grand River Transit lists COVID-19 cases on its website for transparency purposes, but some details are not released due to privacy concerns.

Since the on-set of the pandemic, multiple safety precautions have been put in place to protect drivers and riders, including barriers and mandatory masks.

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Microplastics could be eliminated from wastewater at source – E&T Magazine

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A team of researchers from the Institut national de la recherche scientifique (INRS), Quebec, Canada, have developed an electrolytic process for treating wastewater, degrading microplastics at the source.

Microplastics are fragments of plastic less than 5mm long, often contained in toiletries or shedding from polyester clothing. They are present in virtually every corner of the Earth, and pose a particularly serious threat to marine ecosystems. High concentrations of microplastics can be carried into the environment in wastewater.

There are no established degradation methods to handle microplastics during wastewater treatment; although some techniques exist, these involve physical separation as a means of filtering the pollutant. These techniques do not degrade microplastics, which requires additional work to manage the separated fragments. So far, research into degradation of microplastics has been very limited.

The INRS researchers, led by water treatment expert Professor Patrick Drogui, decided to try degrading plastic particles through electrolytic oxidation – a process that does not require the addition of chemicals.

“Using electrodes, we generate hydroxyl radicals to attack microplastics,” Drogui said. “This process is environmentally friendly because it breaks them down into CO2 and water molecules, which are non-toxic to the ecosystem.”

Drogui and his colleagues experimented with different anode materials and other parameters such as current intensity, anode surface, electrolyte type, electrolyte concentration and reaction time. They found that the electrolytic oxidation could degrade more than 58 ± 21 per cent of microplastics in one hour. The microplastics appeared to degrade directly into gas rather than breaking into smaller particles.

Lab-based tests on water artificially contaminated with fragments of polystyrene showed a degradation efficiency as high as 89 per cent.

“This work demonstrated that [electrolytic oxidation] is a promising process for degradation of microplastics in water without production of any waste or by-products,” the researchers wrote in their Environmental Pollution report.

Drogui envisions this technology being used to treat microplastic-rich wastewater emerging from sources such as commercial laundries.

“When this commercial laundry water arrives at the wastewater treatment plant, it is mixed with large quantities of water, the pollutants are diluted and therefore more difficult to degrade,” he explained. “Conversely, by acting at the source, i.e. at the laundry, the concentration of microplastics is higher, thus more accessible for electrolytic degradation.”

Next, the researchers will move on to experimenting with degrading microplastics on water outside the artificial laboratory environment. Real commercial laundry water contains other materials that can affect the degradation process, such as carbonates and phosphates, which can trap radicals and limit degradation. If the technology is effective under these circumstances, the researchers plan to conduct a study to determine the cost of scaling up this treatment to implement in laundries.

Last week, researchers from the University of Barcelona published a study suggesting that encouraging a greater proliferation of seagrass meadows in the shallows of oceans could help trap, extract and carry marine plastic debris to shore.

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