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Universe and Solar System

Universe and Solar System

Devil Comet

Mount Everest-sized Devil comet hurtling in Earth’s direction could explode today. Pons-Brooks Comet - Comet 13P/Pons-Brooks, also called the Devil Comet, is about the size of Mount Everest and it is hurtling towards Earth. After an outburst in July, scientists believe that the comet could explode once again today. Ice volcanoes on the comet have erupted at least six times in 2023. That eruption caused the comet to distort into a horseshoe or horned shape. Near Earth - When the comet reaches the closest point to the Sun in its orbit, it will be at a distance of 0.8 astronomical units. One…

31 December, 2023 Universe and Solar System

Ningaloo Eclipse

Ningaloo Eclipse On April 20, 2023, people saw the Ningaloo Eclipse. Due to the curvature of the earth's surface and the transition from an annular to a total eclipse, it is a rare 'hybrid solar eclipse'. The following one won't show up until 2031, the last of which was spotted in 2013. What are the Key Aspects of the Hybrid Solar Eclipse? Australia, Timor-Leste, and Indonesia's West and Papua provinces were able to see the total solar eclipse. Southeast Asia, the East Indies, Australia, the Philippines, and New Zealand all witnessed a partial solar eclipse at the same time. India…

26 April, 2023 Universe and Solar System

Green Comet

Green Comet After 50,000 years, the Comet C/2022 E3 (ZTF), sometimes known as the "Green Comet," is now approaching Earth. More on the news: The US-based Zwicky Transient Facility (ZTFwide-field )'s survey camera made the initial discovery of the comet in March 2022. Following its first discovery by the Zwicky Transient Facility (ZTF), the comet was named C/2022 E3 (ZTF). It is currently travelling away from the sun along its own orbit after coming close to it in the middle of January. Several locations across the world may now see the comet as it approaches Earth. The comet, which originates…

28 January, 2023 Universe and Solar System

Sun's Atmosphere, ARIES Facility and Aditya-L1

ARIES Facility will host the support center for Aditya-L1 Sun’s Atmosphere The atmosphere of the sun is composed of several layers, mainly the photosphere, the chromosphere and the corona. It's in these outer layers that the sun's energy, which has bubbled up from the sun's interior layers, is detected as sunlight. Photosphere The lowest layer of the sun's atmosphere is the photosphere. It is about 300 miles (500 km) thick. This layer is where the sun's energy is released as light. Because of the distance from the sun to Earth, light reaches our planet in about eight minutes. The photosphere…

18 April, 2021 Universe and Solar System

What caused the tilt to Saturn’s rotation axis?

What caused the tilt of Saturn’s rotation axis? The tilt of the rotation axis of the gas giant Saturn may in fact be caused by its moons, scientists from CNRS, Sorbonne University and the University of Pisa have reported (Nature Astronomy). The current tilt of Saturn's rotation axis is caused by the migration of its satellites, and especially by that of its largest moon, Titan. Recent observations have shown that Titan and the other moons are gradually moving away from Saturn much faster than astronomers had previously estimated. By incorporating this into their calculations, the researchers concluded that this process…

31 January, 2021 Universe and Solar System

The Milky Way’s secret

The Milky Way’s secret Context: 2020 Nobel Prize in physics has been awarded to Roger Penrose, Reinhard Genzel and Andrea M. Ghez for their work on black holes. Important terminologies: 1. Event Horizon: It is defined as a notional boundary around a black hole beyond which no light or other radiation can escape. 2. Quasars: A quasar is an extremely luminous active galactic nucleus (AGN), in which a super massive black hole with very high mass is surrounded by a gaseous accretion disk. Quasars are found in the centres of some galaxies and powered by gas spiralling at high velocity…

11 October, 2020 Universe and Solar System

What discovery of phosphine gas in the atmosphere of Venus means

What discovery of phosphine gas in the atmosphere of Venus means Context: Recently, phosphine gas in the atmosphere of Venus was discovered by an international team of astronomers. The discovery throws light about the possibility of the presence of life forms on Venus. European Space Agency’s mission, Venus Express, found signs of ozone, made of three oxygen atoms and considered a biomarker, in the upper atmosphere of Venus, in 2011. Traces of phosphine, another biomarker, in its atmosphere has just given the search for extra-terrestrial life a shot in the arm. Importance of Space Missions: Space Mission is a journey,…

19 September, 2020 Universe and Solar System

Great Oxidation Event (GOE)

Great Oxidation Event (GOE) The Great Oxidation Event (GOE), sometimes also called the Great Oxygenation Event, Oxygen Catastrophe, Oxygen Crisis, Oxygen Holocaust, or Oxygen Revolution, was a time period when the Earth's atmosphere and the shallow ocean experienced a rise in oxygen, approximately 2.4 billion years ago (2.4 Ga) to 2.1–2.0 Ga during the Paleoproterozoic era. Geological, isotopic, and chemical evidence suggests that biologically produced molecular oxygen (dioxygen, O2) started to accumulate in Earth's atmosphere and changed Earth's atmosphere from a weakly reducing atmosphere to an oxidizing atmosphere, causing many existing species on Earth to die out. The cyanobacteria producing…

05 July, 2020 Universe and Solar System

Scientists detect ionospheric irregularities

Scientists detect ionospheric irregularities during major space weather events that influence communication & navigation systems The Earth's magnetic field lines are nearly horizontal over magnetic equator due to which equatorial ionosphere is a bed for a variety of plasma instabilities to cause plasma disturbances and plasma irregularities. These plasma irregularities pose severe problems to the communication and navigation systems and interfere with surveillance operations as well as disruption in detection and tracking of aircraft, missiles, and satellites. A multi-instrument based ionospheric study of space weather storms over India by the Scientists from the Indian Institute of Geomagnetism (IIG) an autonomous…

23 June, 2020 Universe and Solar System

Blazars

Blazars  Study of optical properties of super-massive black-hole can provide a clue to emission mechanism from its close vicinity Context Through 153 nights, 17 scientists from 9 countries in Europe and Asia including researchers from Aryabhatta Research Institute of Observational Sciences (ARIES), Nainital, an autonomous institution of the Department of Science and Technology (DST), Government of India took 2263 image frames and observed the changes in a very high energy gamma-ray emitting blazar ‘1ES 0806+524’ using seven optical telescopes in Europe and Asia. Blazar A blazar is a feeding super-massive black-hole (SMBH) in the heart of a distant galaxy that…

23 June, 2020 Universe and Solar System

Star Clusters

Star Clusters Study showing stars of varied ages can co-exist in open clusters, provides a clue to stellar evolution in the Milky Way Galaxy Stars Stars in our Galaxy are formed from the molecular clouds present in the Galaxy. It is believed that the majority of stars in our Galaxy are formed in star clusters making them important clues to understanding the star formation mechanism. Open star clusters are a system of stars bound by gravity in which stars are born from the same molecular clouds. All the stars in a cluster follow the evolutionary sequence as per their initial masses…

22 June, 2020 Universe and Solar System

Extreme Helium Stars (EHe)

Extreme Helium Stars (EHe) An extreme helium star or EHe is a low-mass supergiant that is almost devoid of hydrogen, the most common chemical element of the universe. There are 21 of them detected so far in our galaxy. Mystery of EHe resolved The origin and evolution of these Hydrogen deficient objects have been shrouded in mystery. Their severe chemical peculiarities challenge the theory of well-accepted stellar evolution as the observed chemical composition of these stars do not match with that predicted for low mass evolved stars. A study by the Indian Institute of Astrophysics (IIA) an autonomous institute of…

22 June, 2020 Universe and Solar System

Water worlds

Water worlds Saturn’s moon Enceladus and Jupiter’s moon Europa are still interesting as candidates that may support life because scientists have spotted water plumes bursting from their icy shells. NASA guesses that more than many exoplanets could be ‘water worlds’. This includes some members of the Trappist-1 system which is 40 light years away.

21 June, 2020 Universe and Solar System

India’s deepest solar eclipse

India’s deepest solar eclipse India will witness its “deepest” annular solar eclipse of this century this Sunday (June 21), with the Sun appearing as a necklace of pearls for around 30 seconds during the maximum phase along a narrow corridor running through Rajasthan, Haryana and Uttarakhand. The eclipse will be partial in the rest of the country. An annular solar eclipse occurs when the apparent size of the Moon is slightly less than that of the Sun, which leaves the outer rim of the latter uncovered, giving the appearance of a “ring of fire”. During this eclipse, that ring is…

17 June, 2020 Universe and Solar System

Great Oxidation Event (GOE)

Great Oxidation Event (GOE) The atmosphere of early Earth contained little molecular oxygen. A significant increase in oxygen occurred ca. 2.4–2.0 billion years ago in what is called the Great Oxidation Event (GOE). A large positive excursion in carbon isotopic composition in sedimentary carbonates is known to have occurred 2.2–2.0 billion years ago (the Lomagundi-Jatuli event), which provides evidence for an enhanced rate of organic carbon burial, i.e., enhanced net production of oxygen. The Proterozoic snowball Earth event (global glaciation) occurred 2.3–2.2 billion years ago, roughly coinciding with the GOE. Thus, a causal relationship between the GOE and the snowball…

14 June, 2020 Universe and Solar System

Band-like clouds seen over Sun’s neighbour-Luhman 16A

Band-like clouds seen over Sun’s neighbour-Luhman 16A A group of international astrophysicists have identified cloud bands on the surface of Luhman 16A, one of a pair of binary brown dwarfs in the Vela constellation. They have used an idea put forth Indian astrophysicist Sujan Sengupta, who is at the Indian Institute of Astrophysics, Bengaluru, that the light emitted by a cloudy brown dwarf, or reflected off an extrasolar planet, will be polarised. He suggested that a polarimetric technique could serve as a potential tool to probe the environment of these objects. Subsequently, many astronomers detected the polarisation of brown dwarfs.…

08 May, 2020 Universe and Solar System

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