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Research has shown that the closest black hole to Earth exists in the Hyades Cluster, about 150 light years away. The Hyades is an open star cluster located closest to Earth.

In an observation report published on the 18th, a research team from the University of Padua, Italy, raised the possibility that several massive black holes exist in the Hyades star cluster, located about 150 light-years away in the constellation of Taurus.

Open clusters are thought to be a collection of hundreds of stars that were born at the same time. Most stars that make up a cluster have common chemical properties. Astronomers believe that the Hyades cluster contains about 500 stars of various masses.

The Hyades open cluster contains stars of various masses. <사진=미 항공우주국(NASA) 공식 홈페이지>

While looking at the stars that make up the Hyades cluster, the research team came up with the possibility that several small black holes exist. If their hypothesis is correct, the black hole closest to Earth has been identified.

An investigation official explained, “Because black holes do not emit light, they cannot be directly observed. Therefore, we simulated the motion and evolution of stars in the Hyades cluster and compared the results with the stars’ actual positions and speeds.”

The star’s position and speed data were obtained from the latest data from the European Space Agency’s (ESA) observation satellite ‘Gaia’. ‘Gaia’ is tracking the movements of billions of stars to create a 3D map of our galaxy.

An imaginary view of the black hole Gaia BH1, located about 1560 light years from Earth. <사진=미국 국립과학재단(NSF) 국립광학적외선천문학연구소(NOIRLab)·M.Zamani>

A research official said, “In this analysis, we identified the possibility that two to three small black holes exist in or near the Hyades Cluster. In this simulation, it is also possible to assume that some black holes currently or recently existed in the central part of the Hyades Cluster. “It does,” he said.

The astronomy community has chosen ‘Gaia BH1’ as the closest black hole to Earth. ‘Gaia BH1’ is 1560 light-years away in the direction of the constellation Ophiuchus. If the University of Padua research team’s hypothesis is true, the distance of the black hole closest to Earth will be reduced by one-tenth.

The results of this research, conducted jointly by the European Southern Astronomical Observatory (ESO), the Institute for Space Sciences at the University of Barcelona (ICCUB-IEEC) in Spain, the University of Cambridge in the UK, and Sun Yat-Sen University in China, were first introduced in the Journal of the Royal Astronomical Society.

Reporter Jeong Ian anglee@sputnik.kr

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A new claim has been made that ‘stratospheric aerosol injection’, which has been proposed to slow the polar warming that causes the collapse of the West Antarctic ice sheet, has little practical effect.

In a research report recently published by a research team from the University of Bern in Germany, the claim to arbitrarily release aerosols into the stratosphere to mitigate polar warming is very small compared to the effort invested.

Stratospheric aerosol injection is one of the ‘Solar Radiation Modification (SRM)’ technologies. Aerosols are naturally emitted following large-scale volcanic eruptions, and stratospheric aerosol injection physically realizes the phenomenon of blocking sunlight.

The consensus in the scientific world is that if global warming continues as it is now, the West Antarctic ice sheet collapse cannot be prevented. <사진=pixabay>

The research team set out to simulate whether this method, which has recently attracted attention, is really effective. Assuming three future greenhouse gas reductions: ‘reduction above expectations’, ‘moderate reduction’, and ‘no reduction’, respectively, aerosol injection was simulated to be conducted in 2020, 2040, 2060, and 2080. All scenarios lasted until 2300.

As a result, it was confirmed that the West Antarctic ice sheet melted due to the warming of the Antarctic region in all scenarios. Although the rate of melting differed among scenarios, it was concluded that the stratospheric blast of an aerosol would not have an immediate effect and would have to be sustained over a fairly long period of time.

“Even if aerosol injection is executed immediately, this method will have to be maintained for thousands of years to be effective,” said an official in charge of the experiment.

A method of physically spraying aerosol into the stratosphere to reduce the amount of incident on the ground is being devised. <사진=pixabay>

Currently, scholars are studying SRM as a way to mitigate global warming, in addition to reducing greenhouse gas emissions themselves. Among SRMs that encompass technologies that reduce the amount of sunlight reaching the ground, stratospheric aerosol injection is receiving a lot of attention.

“Aerosol, which refers to solid or liquid particles dispersed in a gas, reflects sunlight and lowers the average temperature,” said an official in the experiment. We cannot guarantee that, and we are concerned about potential adverse effects.”

Scholars who study SRM believe that if the global temperature rises by more than 2℃ compared to pre-industrial revolution, the adverse effects on human and animal ecosystems will increase. In terms of climate change measures, 2℃ is regarded as the last chance given to humans. The 2015 Paris Agreement also adopted a plan to limit the increase in global average temperature to less than 2 degrees Celsius.

Reporter Yoonseo Lee lys@sputnik.kr

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The possibility that huge waves generated by tidal action repeatedly act on one of the two stars that make up the binary system has been raised through the latest research. This is the first time that the effects of tidal waves observed in a so-called Heartbeat Star have been confirmed on a star.

A research team at the Harvard-Smithsonian Center for Astrophysics (CfA) has recently announced that it has captured a destructive phenomenon in which a huge tidal wave rushes into one of the two stars that make up the binary system.

The binary star system in which tidal waves that are so massive that it shatters the Earth hits one star is ‘MACHO 80.7443.1718’ near the Large Magellanic Cloud, about 169,000 light-years away from Earth to be exact.

An artist’s imagination of ‘MACHO 80.7443.1718’ by heartbeat. The tidal waves exerted on the primary star by conjunction were estimated to affect 20% of the primary star’s radius. <사진=Melissa Weiss·CfA 공식 홈페이지>

The mass of the star that makes up the binary system is estimated to be approximately 35 times that of the Sun. The companion star’s mass is much smaller than that. The two stars are typical heartbeat stars, orbiting each other in nearly elliptical orbits. The name was given because the brightness periodically changes like a heartbeat when stars pass close to each other at the point where each orbit meets.

One thing to note in ‘MACHO 80.7443.1718’ is the tremendous tidal force. An official from the research team said, “Whenever the orbiting star and companion come close to each other, tidal action occurs like the Earth and the moon due to each other’s gravity.” It seems,” he said.

“This is a common phenomenon for heartbeat stars, but in the case of ‘MACHO 80.7443.1718’, the brightness fluctuation reached 200 times the predicted value.” It’s enough energy to destroy it over and over again.”

Trajectories of heartbeat stars. When two celestial bodies come close along interlocking orbits, tidal force causes periodic changes in brightness. <사진= NASA Space News 유튜브 공식 채널 영상 'The Star with the Biggest Waves Ever: How a Heartbeat Star Creates Waves as High as Three Suns' 캡처>

The center gave meaning to the fact that these highly fluctuating heart rate stars were so far unknown. An official from the research team predicted, “The tidal wave generated by the gravitational interaction of ‘MACHO 80.7443.1718’ will reach about 4.3 million km, which is 20% of the radius of the main star.”

The research team plans to continue observation activities to find more stars that emit light by tidal waves. Heartbeat stars are actively observed through NASA’s Kepler telescope, and about 1,000 have been identified so far. Twenty of these generate extreme tidal waves, such as ‘MACHO 80.7443.1718’.

Reporter Jeong Ian anglee@sputnik.kr

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The Nancy Grace Roman Telescope (Roman Telescope), which is being developed by NASA at a cost of 3.2 billion dollars (approximately 4.2 trillion won), drew attention to the observation of wandering planets four years before its launch.

NASA said on its official SNS on the 4th that the development of the Roman Telescope is going well, and that there is now a good chance of meeting the scheduled launch date of 2027.

The Roman Telescope, named after former NASA astronomer Nancy Grace Roman, who passed away in 2018, is evaluated as an instrument optimized for observing distant galaxies and exoplanets. In particular, NASA predicted in a report on the 19th of last month that the Roman Telescope would catch about 400 stray planets similar in size to Earth.

Artist’s rendering of an Earth-mass stray planet <사진=NASA 고다드 우주비행센터 공식 홈페이지>

A wandering planet is a celestial body that floats freely in outer space without orbiting around a star. A research team led by David Bennett, a senior researcher at NASA’s Goddard Space Flight Center, who has studied stray planets whose orbital axis is at the center of the galaxy for nine years, claimed in a recent report that trillions of stray planets may exist in the Milky Way. In particular, the research team predicted that most of the wandering planets in the Milky Way had a mass similar to that of Earth.

Astronomers pay attention to stray planets because they are important to the study of the evolution of the universe. Wandering planets are presumed to be bound to the gravitational pull of the celestial body to which the main star belongs and fall apart, or to be born alone in the interstellar cloud like a star or brown dwarf.

In other words, it is a popular opinion in the astronomy community that understanding the birth and growth of wandering planets can take one step closer to the evolution of galaxies. For reference, among the wandering planets discovered so far, the closest to Earth is about 100 light years away.

Comparison of observation areas of the Hubble Space Telescope (right) and the Roman Telescope <사진=NASA 고다드 우주비행센터 공식 홈페이지>

The primary mirror of the Roman Telescope is 2.4 m in diameter, the same as that of the Hubble Space Telescope launched in 1990. However, the wide-field near-infrared camera WFI (Wide Field Instrument) mounted here has a field of view 100 times that of the Hubble Space Telescope, and is equipped with the latest 300 million-pixel imaging device.

Thanks to this, the Roman Telescope has a field of view 100 times that of the Hubble Space Telescope and can map galaxies 1000 times faster than the Hubble Space Telescope. In this process, it is expected to more effectively look into objects that are difficult to observe, such as stray planets formed in space or kicked out of the stellar system.

NASA estimates that the Roman Telescope will be 10 times more sensitive to stray satellites than other space telescopes. The Roman Telescope, which specializes in super-precision and wide-field observations, is expected to more reliably capture the gravitational lensing effect in which the light of a star located behind a very small celestial body is distorted and magnified by the gravitational force of the celestial body.

The Roman Telescope scheduled for launch in May 2027 <사진=NASA 고다드 우주비행센터 공식 홈페이지>

Gravitational lensing is a phenomenon in which space-time is distorted by the enormous mass of a celestial body, distorting the direction of light from the opposite celestial body. If the mass of a star is more than 1 million times that of the Sun, it is called a normal gravitational lens, and if it is smaller than 1 million times and greater than 1/10,000, it is called a microgravity lens.

Gravitational lensing is a way to find exoplanets that are incredibly distant, but they pass by only once every few million years and are hard to spot unless you have a reasonably powerful instrument.

Professor Takahiro Sumi of Osaka University, Japan, who participated in NASA’s wandering planet research, said, “The gravitational lens is essentially the only way to discover celestial objects such as low-mass wandering planets and primordial black holes.” , the process of discovering a celestial body that has not been encountered so far will be truly amazing.”

Reporter Jeong Ian anglee@sputnik.kr

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A triple protostar (protostar) that grows while vigorously inhaling a huge gas band like the vortex arms of a galaxy was captured by a radio telescope.

The European Southern Astronomical Observatory (ESO), which operates ALMA, a large-scale radio telescope in the Chilean Atacama Desert, announced on its official channel on the 4th that the triple protostar ‘IRAS’ developed by international astronomy research teams from Seoul National University, the United States, Taiwan, and Denmark. Introduced the observation results of ‘04239+2436’.

An international research team led by Seoul National University Department of Physics and Astronomy Professor Lee Jung-eun and Earth Science Education Professor Kwon Woo-jin tried to capture the reality of a protostar, the early stage of a star. In the process of observing 19 compressed protostar candidates with the large radio interferometer Alma, it was confirmed that the three protostars in ‘IRAS 04239+2436’ have three huge bands that supply gas, the material of the celestial body.

Imaginary map of ‘IRAS 04239+2436’, a triple protostar captured by an international research team participated by Seoul National University using the Alma radio telescope. <사진=ESO 공식 홈페이지>

An investigation official said, “As a result of observing the radio waves generated by the gas around ‘IRAS 04239+2436’ using Alma, the truth was revealed in detail.” There were three bands of gas that looked like vortex arms spanning an astronomical unit (one astronomical unit is about 150 million km).”

“We not only identified the mysterious gas belt, but also succeeded in deriving the speed at which gas moves from Alma’s frequency change,” said the official. I came to the conclusion that I play the role of a streamer who does.”

The research team gave meaning that this discovery revealed in detail the dynamic formation process of multiple protostars. Protostar is the initial stage of star birth, and most stars such as the sun are thought to be born in multistars with two or more stars, such as ‘IRAS 04239+2436’.

The triple protostar ‘IRAS 04239+2436’ (left) captured by the Alma Telescope. 1, 2, and 3 indicate gas bands in the form of vortex arms, respectively. Two protostars are distributed in area A and one in area B. On the right is ‘IRAS 04239+2436’ as seen through numerical simulation, and + indicates the location of each protostar. <사진=EOS 공식 홈페이지>

An official of the investigation said, “The formation mechanism of multiplicity where protostars gather is important in understanding the birth of a star, but it has never been observed in detail.” It is happening,” he explained.

“Streamers show how protostars grow as they inhale gas, but how they form is still unknown.” Additional high-resolution observations are needed,” he stressed.

Reporter Jeong Ian anglee@sputnik.kr

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