Latest news with #GRS1915+105
India Today
4 days ago
- Science
- India Today
Indian scientists decode mysterious signal pattern coming from deep space
India's space observatory AstroSat has uncovered new clues about the mysterious behaviour of a distant black hole, GRS 1915+105, revealing how it flickers in X-rays with remarkable 28,000 light-years away in our Milky Way galaxy, this black hole system is helping scientists decode the extreme environment near one of the universe's most powerful its launch in 2015, AstroSat — India's first dedicated multi-wavelength space telescope — has been continuously monitoring GRS 1915+105. A team of Indian scientists from ISRO, IIT Guwahati, and the University of Haifa used two of its onboard instruments, the Large Area X-ray Proportional Counter (LAXPC) and the Soft X-ray Telescope (SXT), to study the black hole's mysterious signal They found a repeating pattern: a few hundred seconds of dim X-ray light, followed by a similar period of bright light. During the brighter phases, they discovered something remarkable — fast X-ray flickers occurring 70 times per second, known as Quasi-periodic Oscillations (QPOs). These flickers vanished during the dimmer team traced this rapid flickering to the corona, a superheated cloud of plasma surrounding the black hole. During the bright phases, the corona becomes smaller and hotter, generating strong the dim phases, it cools and expands, causing the flickers to black hole is part of a binary system, pulling matter from a companion star into a hot spinning disc. As this matter heats up, it emits X-rays — the signals that AstroSat study, published in the Monthly Notices of the Royal Astronomical Society, provides scientists with a deeper insight into black hole findings showcase India's growing capabilities in space-based astronomy and the powerful role of AstroSat as a cosmic observatory.- EndsTrending Reel
United News of India
6 days ago
- Science
- United News of India
Indian scientists decode rhythms of a Black Hole: A discovery with AstroSat
Chennai, July 26 (UNI) ISRO today said India's first dedicated multi-wavelength space observatory, AstroSat, has been continuously monitoring the enigmatic black hole--the universe's most enigmatic powerhouses--since its launch in September 2015 and was providing invaluable insights into source's behaviour. A group of Indian scientists from University of Haifa, IIT Guwahati, Indian Space Research Organization (ISRO) observed that the X-ray brightness from GRS 1915+105 fluctuates dramatically over time", it said. This research deepens our understanding of black holes also also highlights India's growing role in space-based astronomy. Black holes, the universe's most enigmatic powerhouses, cannot be seen directly, but their immense gravity reveals their presence. Born from the collapse of massive stars that exhaust their fuel, these cosmic voids are invisible because not even light can escape their grasp. However, a black hole in a binary system with a companion star, triggers a dramatic process known as accretion, pulling in stellar material that spirals inward and heats up to over 10 million degrees (far hotter than the Sun's surface temperature of 6000 degrees). This 'super-heated' matter emits intense X-rays, which are captured by space telescopes, offering scientists a rare window into the otherwise hidden lives of black holes. In a distant corner of our galaxy (nearly 28000 light-years away) lies one of the most fascinating and mysterious black hole, GRS 1915+105. This intriguing black hole X-ray binary system, consisting of a rapidly rotating black hole with a mass about 12 times that of a Sun and its companion star, has captured the attention of scientists due to its unusual and dynamic behaviour. ISRO also depicted a schematic diagram of the complex accretion process around GRS 1915+105, forming a swirling disc (1-10 million degree) and corona (∼100 million degree) structure. "India's first dedicated multi-wavelength space observatory, AstroSat, has been continuously monitoring the enigmatic black hole GRS 1915+105 since its launch (September 2015) and provides invaluable insights into source's behaviour. Using two of its onboard instruments, namely Large Area X-ray Proportional Counter (LAXPC) and Soft X-ray Telescope (SXT), a group of Indian scientists from University of Haifa, IIT Guwahati, Indian Space Research Organization observed that the X-ray brightness from GRS 1915+105 fluctuates dramatically over time", it said. It exhibits a unique pattern of alternating low-brightness ('dips') and high-brightness ('non-dips') phases, each lasting a few hundred seconds. During the high-brightness phase, the team discovered something remarkable: rapid flickers in X-rays repeating about 70 times per second, known as Quasi-periodic Oscillations (QPOs). Interestingly, such 'fast' flickers vanish during the low-brightness phases. Explaining on what causes these mysterious 'fast' flickers', the research team uncovered that these rapid QPOs are intimately connected to a 'super-heated' cloud of energetic plasma surrounding the black hole, known as corona. During the bright high-energy phases when QPOs are strongest, the corona becomes more compact (smaller in size, R_(in) ) and significantly hotter (higher luminosity, L). Conversely, in the dimmer 'dip' phases, the corona expands (larger R_(in) ) and cools (smaller L), causing the flickers to vanish. This pattern suggests that the compact oscillating corona seems to be the origin of these fast QPO signals. These findings help scientists understand what happens in the vicinity of a black hole, where gravity is incredibly strong and conditions are extreme. Indeed, GRS 1915+105 acts as cosmic laboratory, and with AstroSat's remarkable contributions, Indian scientists are decoding the 'whispers' of this black hole. This work have been published in the prestigious journal, Monthly Notices of Royal Astronomical Society co-authored by Anuj Nandi (ISRO), Santabrata Das (IIT Guwahati), Sreehari H. (Haifa University) and Seshadri Majumder (IIT Guwahati). Overall, this research not only deepens our understanding of black holes but also highlights India's growing role in space-based astronomy. UNI GV 1030
New Indian Express
6 days ago
- Science
- New Indian Express
ISRO shares new findings on black hole
BENGALURU: A team of scientists and researchers from the Indian Space Research Organisation (ISRO) on Friday listed out their unique findings while studying the Black Hole as part of their noted that the X-ray brightness from the fascinating and mysterious black hole, GRS 1915+105, fluctuates dramatically over time. It exhibits a unique pattern of alternating low-brightness ('dips') and high-brightness ('non-dips') phases, each lasting a few hundred seconds. During the high-brightness phase, the team discovered that the rapid flickers in X-rays were repeating about 70 times per second, known as Quasi-periodic Oscillations (QPOs). Interestingly, such 'fast' flickers vanish during the low-brightness phase, noted the researchers Anju Nandi from ISRO, Santabrata Das from IIT- Guwahati, Sreehari H from Hafiza University and Seshadri Majumder from IIT Guwahati. India's first dedicated multi-wavelength space observatory, AstroSat, has been continuously monitoring the black hole GRS 1915+105 since its launch in September 2015 and is working to provide insights into the source's behaviour. The research team stated that they found that these rapid QPOs are intimately connected to a super-heated cloud of energetic plasma surrounding the black hole, known as the corona. During the bright, high-energy phases when QPOs are strongest, the corona becomes more compact and significantly hotter with higher luminosity. Conversely, in the dimmer dip phases, the corona expands and cools, causing the flickers to vanish. This pattern suggests that the compact oscillating corona seems to be the origin of these fast QPO signals. This research work titled- Evidence of oscillating 'compact' Comptonised corona in GRS 1915+105: insights into HFQPOs with AstroSat- was also published in the journal Monthly Notices of the Royal Astronomical Society, on July 4, 2025. ISRO shared the details on July 25. The research team noted that these findings will help scientists understand what happens in the vicinity of a black hole, where gravity is incredibly strong and conditions are extreme.
News18
6 days ago
- Science
- News18
AstroSat helps decode mysterious black hole flickers: ISRO
Bengaluru, Jul 25 (PTI) Indian scientists are employing AstroSat, the country's first dedicated multi-wavelength space observatory, to understand the complex behaviour exhibited by the black hole system GRS 1915+105, the ISRO said. The study conducted by researchers from ISRO, IIT Guwahati, and the University of Haifa (Israel), has revealed that the X-ray brightness from the black hole fluctuates rapidly, alternating between low brightness (dip) and high-brightness (non-dip) phases, each lasting a few hundred seconds. During these high-brightness phases, the team observed rapid X-ray flickers about 70 times per second, which is known as Quasi-Periodic Oscillations (QPOs). The research team uncovered that these rapid QPOs are intimately connected to a 'super-heated' cloud of energetic plasma surrounding the black hole, known as Corona. During the bright high-energy phases when QPOs are strongest, the corona becomes more compact and significantly hotter. Conversely, in the dimmer 'dip' phases, the corona expands and cools, causing the flickers to vanish. This pattern suggests that the compact oscillating corona seems to be the origin of these fast QPO signals, ISRO noted in a statement. This discovery was made using AstroSat's Large Area X-ray Proportional Counter (LAXPC) and Soft X-ray Telescope (SXT). 'These findings help scientists understand what happens in the vicinity of a black hole, where gravity is incredibly strong and conditions are extreme," ISRO said. GRS 1915+105, with a mass about 12 times that of a Sun, is located about 28,000 light-years away. The study has been published in the Monthly Notices of the Royal Astronomical Society and co-authored by Anuj Nandi (ISRO), Santabrata Das and Seshadri Majumder (IIT Guwahati), and Sreehari H (University of Haifa). PTI GMS GMS ROH view comments First Published: July 25, 2025, 22:15 IST Disclaimer: Comments reflect users' views, not News18's. Please keep discussions respectful and constructive. Abusive, defamatory, or illegal comments will be removed. News18 may disable any comment at its discretion. By posting, you agree to our Terms of Use and Privacy Policy.
New Indian Express
6 days ago
- Science
- New Indian Express
ISRO scientists share new findings while studying Black Hole GRS 1915+105
BENGALURU: A team of scientists and researchers from the Indian Space Research Organisation (ISRO) on Friday listed out their unique findings while studying the Black Hole as part of their study. They noted that the X-ray brightness from fascinating and mysterious black hole- GRS 1915+105- fluctuates dramatically over time. It exhibits a unique pattern of alternating low-brightness ('dips') and high-brightness ('non-dips') phases, each lasting a few hundred seconds. During the high-brightness phase, the team discovered that the rapid flickers in X-rays were repeating about 70 times per second (frequency 〖ν〗_(QPO) ∼70 Hz), known as Quasi-periodic Oscillations (QPOs). Interestingly, such 'fast' flickers vanish during the low-brightness phase, noted the researchers Anju Nandi from ISRO, Santabrata Das from IIT- Guwahati, Sreehari H from Hafiza University and Seshadri Majumder from IIT Guwahati. India's first dedicated multi-wavelength space observatory, AstroSat, has been continuously monitoring the black hole GRS 1915+105 since its launch in September 2015 and is working to provide insights into source's behaviour. Explaining what causes the mysterious fast flickers, the research team in the report stated that they found that these rapid QPOs are intimately connected to a super-heated cloud of energetic plasma surrounding the black hole, known as corona. During the bright high-energy phases when QPOs are strongest, the corona becomes more compact and significantly hotter with higher luminosity. Conversely, in the dimmer dip phases, the corona expands and cools, causing the flickers to vanish. This pattern suggests that the compact oscillating corona seems to be the origin of these fast QPO signals.
