The data for the survey, which spanned a large part of the Milky Way, was gathered using two powerful radio telescopes: the Karl G Jansky Very Large Array (VLA) at the National Radio Astronomy Observatory (NRAO), USA, and the Effelsberg 100-m radio telescope operated by the Max Planck Institute for Radio Astronomy (MPIfR), Germany, as part of the GLOSTAR (Global View on Star formation in the Milky Way) project.   

Nirupam Roy, Assistant Professor at the Department of Physics, and Rohit Dokara, his former undergraduate student from IISc, as well as Jagadheep D Pandian, Associate Professor at the Department of Earth and Space Sciences in IIST are among the Indian scientists who are part of the GLOSTAR project.   

Dokara, now a PhD student at MPIfR, is the first author on one of the papers that reports the detection of new supernova remnants (SNRs) – structures born from the explosive death of massive stars – in our galaxy.  

Previous surveys have detected only about one-third of the expected number of SNRs in the Milky Way (which is nearly 1000). The GLOSTAR team has now discovered 80 new SNR candidates in the VLA data alone, with more expected to be identified from the combined Effelsberg and VLA data. They are also able to confirm the presence of 77 previously discovered SNR candidates and reclassify a few that were misidentified. This is impressive considering that the northern telescopes utilised by GLOSTAR can see only half of the inner regions of the Milky Way. “This is an important step to solve this long-standing mystery of the missing supernova remnants,” says Dokara.  

The researchers were also able to detect other traces of star formation. One of them, for example, is radio emission from methanol molecules in a nearby large star-forming complex called Cygnus X. These are typically emitted from massive stars in the very early stages of formation. The team was also able to detect dense pockets of ionised hydrogen, another tell-tale sign of the presence of massive young stars.   

Young stars are usually surrounded by thick clouds of dust and gas. “Because visible light gets absorbed in this dense cloud around stars, most of the optical telescopes don’t reveal much. What people look for, instead, are radio emissions,” explains Roy, who has previously worked at both NRAO and MPIfR.   

“Since the GLOSTAR survey detects a wide range of radio emission such as that from methanol molecules to ionised hydrogen, it can probe the formation of massive stars from very early to relatively late stages, which is important to get a complete picture of star formation in the Milky Way,” adds Pandian, who has also previously worked at MPIfR.  

The Effelsberg radio telescope is a single large dish spanning 100 m in diameter, capable of detecting large-scale structures, whereas the VLA is a collection of small antennas which work together as an interferometer to capture the details at high resolution. The data pooled from both telescopes helped the researchers paint a more comprehensive picture of different astrophysical objects in the region.

“This clearly demonstrates that the Effelsberg telescope is still very crucial, even after 50 years of operation,” says Andreas Brunthaler of MPIfR, project leader and first author of the survey’s overview paper. Karl Menten, the Director of MPIfR who initiated GLOSTAR, adds, “It’s great to see the beautiful science resulting from two of our favourite radio telescopes joining forces.” Both Pandian and Roy currently maintain Max Planck-India Partner Groups with Menten to continue the close collaboration and, in particular, to expand the scope of the GLOSTAR project.   

Other members of the research team include scientists from MPIfR and NRAO, and collaborators from institutions in the UK, South Africa, Mexico, France, and Australia. With observations and analysis ongoing, more results are expected to be published over time.  

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Keywords: Star formation, Milky Way, Astronomy, Galaxy, Astronomy & Astrophysics,  Indian Institute of Science, IISc, Indian Institute of Space Science and Technology, IIST   

Under the campaign, high-quality astronomical data sets were distributed to students for analysis and identification of asteroids. Students analyze the data using software which then leads to potential discoveries. These observations feed into the Near-Earth Object (NEO) data being compiled by NASA and the Jet Propulsion Lab (JPL).

The students get access to the real-time data from the ‘PANSTARRS’ (The Panoramic Survey Telescope and Rapid Response System Telescope), located in Hawaii. They access these images and are trained in advanced data analytics to detect asteroids. This accounts for an invaluable real-time research experience.

The campaign called ‘Khagolshala Asteroid Search Campaign’ is an initiative of the Office of Principal Scientific Adviser to the Government of India and SPACE-India, which was established in 2001, to popularize science and inculcate scientific temperament among the masses, especially students in India.

Space India has established Khagolshala Astronomy and Space Education Labs (ASELs) across 20 Jawahar Navodaya Vidyalayas to date. It is working with a vision to get the younger generation in the country engrossed in astronomy and space sciences; application, exploration, innovation, and research in these areas. It works by engaging students through experimentation, observation, and analysis of the universe.

The conferment of the provisional status marks an important step as it could ultimately lead to the asteroids being named by their discoverers though it may take several years for that to happen as it involved an elaborate procedure.

The whole process starts with `preliminary detection’ which is the first, original observation of a new asteroid. This is followed by the `provisional status’. For this, the asteroid must have been observed a second time within the next 7-10 days. Asteroid detections with `provisional status’ are maintained in the International Astronomical Union (IAU)’s Minor Planet Center (MPC) database until there have been a sufficient number of observations to fully determine the orbit. That process typically takes 6-10 years, at which point the asteroid is numbered and catalogued by the IAU. The numbered asteroids can then be finally named by their citizen scientist discoverers.

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keywords: asteroid, International Astronomical Search Collaboration, IASC, research, Near-Earth Object,  data, NASA, Jet Propulsion Lab (JPL), ‘PANSTARRS’, Panoramic Survey Telescope and Rapid Response System Telescope, Hawaii, Office of Principal Scientific Adviser to the Government of India, SPACE-India,

Neutrinos interact very weakly with everything else – trillions of them pass through every human being every second without anyone noticing; a neutrino’s spin always points in the opposite direction of its motion, and until a few years ago, neutrinos were believed to be massless. It is now generally believed that the phenomenon of neutrino oscillations require neutrinos to have tiny masses.

Professor Amitabha Lahiri of S N Bose National Centre for Basic Sciences (SNBNCBS) an autonomous institute under the Department of Science & Technology (DST), Government of India showed in a paper published along with Subhasish Chakrabarty, his student, that the geometry of space-time can cause neutrino oscillations through quantum effects even if neutrinos are massless. It was published in the journal ‘European Physical Journal C’.

Einstein’s theory of general relativity says that gravitation is the manifestation of space-time curvature. According to the SNBNCBS team, neutrinos, electrons, protons and other particles which are in the category of fermions show a certain peculiarity when they move in presence of gravity. Space-time induces a quantum force in addition to gravity between every two fermions. This force can depend on the spin of the particles, and causes massless neutrinos to appear massive when they pass through matter, like the Sun’s corona or the Earth’s atmosphere. Something similar happens for electroweak interactions, and together with the geometrically induced mass it is enough to cause oscillation of neutrinos.

The fuel critical to hydrogen formation is atomic hydrogen gas content of galaxies. Two studies that measured the atomic hydrogen content 9 billion years ago and 8 billion years ago, respectively, have helped them come to this conclusion.

A team of astronomers from the National Centre for Radio Astrophysics (NCRA-TIFR) in Pune, and the Raman Research Institute (RRI), Bangalore, an autonomous institute of the Department of Science and Technology, used the Giant Metrewave Radio Telescope (GMRT) to measure the atomic hydrogen gas content of galaxies 9 billion years ago. This is the earliest epoch in the universe for which there is a measurement of the atomic hydrogen content of galaxies. The new result is a crucial confirmation of the group’s earlier result, where they had measured the atomic hydrogen content of galaxies 8 billion years ago and pushes our understanding of galaxies to even earlier in the universe. The new research has been published in the 2 June 2021 issue of The Astrophysical Journal Letters.

Aditya Chowdhury, a Ph.D. student at NCRA-TIFR and the lead author of both the new study and 2020 one, said, “Our new results are for galaxies at even earlier times, but still towards the end of the epoch of maximum star-formation activity. We find that galaxies 9 billion years ago were rich in an atomic gas, with nearly three times as much mass in atomic gas as in stars. This is very different from galaxies today like the Milky Way, where the gas mass is nearly ten times smaller than the mass in stars.”

The measurement of the atomic hydrogen gas mass was done by using the GMRT to search for a spectral line in atomic hydrogen, which can only be detected with radio telescopes.

“The observations of our study were carried out around 5 years ago, before the GMRT was upgraded in 2018. We used the original receivers and electronics chain of the GMRT before its upgrade,” said Nissim Kanekar of NCRA-TIFR, a co-author of the study.

Barnali Das, another Ph.D. student of NCRA-TIFR, added, “However, we increased our sensitivity by observing for longer, with nearly 400 hours of observations generating large volume of data.”

“The star formation in these early galaxies was so intense that they would consume their atomic gas in just two billion years. And, if the galaxies could not acquire more gas, their star formation activity would decline and finally cease,” said Chowdhury. “It thus appears likely that the cause of the declining star- formation in the Universe is simply that galaxies were not able to replenish their gas reservoirs after some epoch, probably because there wasn’t enough gas available in their environments,” headed.

“With the present result, using a completely different set of receivers and electronics, we now have two independent measurements of the atomic hydrogen gas mass in these early galaxies,” Kanekar pointed out.

K. S. Dwarakanath of RRI, who along with Shiv Sethi, were co-authors of the study, stressed, “Detecting the 21 cm signal from distant galaxies was the main original goal of the GMRT and continues to be a key science driver for building even more powerful telescopes like the Square Kilometre Array. These results are extremely important for our understanding of galaxy evolution.”

The research was funded by the Department of Atomic Energy, India, and the Department of Science and Technology, India.

Scientists from the Indian Institute of astrophysics have pinned down the mechanism behind the Lithium production in low mass red clump stars. Having found lithium excess to be common among the low mass red clump giants, they have now traced Helium (He)-flashing phase of the star’s evolution as the site for high lithium production. This transition phase lasts for about 2 million, during which RGB giants with inert He-core at the centre become red clump giants of He-core burning.

Recently, a group of Astronomers at the Indian Institute of Astrophysics (IIA), Bengaluru, an autonomous institute of the Department of Science & Technology, Government of India, found observational evidence for Li enhancement during the helium-flashing phase of 2 million years, followed by a rapid decrease in Li abundances of such stars. According to their work, it seems Li excess in giants is a transient phenomenon.

The researchers led by Mr. Raghubar Singh and Prof. Eswar Reddy of IIA (including Simon Campbell of Monash Univ, Australia, Bharat Kumar of CAS, China, Matheu Vrard of Ohio State Univ. the USA) used asteroseismology (seismic study of stars using time-resolved photometry from Kepler space telescope) combined with spectroscopic abundances of elements to track the evolution of lithium in a sample of giant stars.  In addition to the evidence for Li production site, a first-of-its-kind correlation between the two independent observed quantities Li abundance and stellar oscillations (gravity mode period spacing) will serve to track the He-flashing phase of converting RGB giant of an inert, electron-degenerate He-core into a fully convective He-burning core by a series of core He-flashes, a theory developed in the 1960s. This work is published in the ‘Astrophysical Journal Letters’.

Lead author Mr. Raghubar Singh said, “We do not have much insight into the He-flash phase, let alone understanding of lithium production.  These new results will inspire further observations as well as theoretical models.”

Talking about the importance of this result, Prof. Eswar Reddy added, “These results will be of great interest to a larger community of theoreticians and observers. This is because of lithium’s broader implications to cosmological models, which predict Big Bang lithium abundance, which is a factor of four less than the presently observed values in the interstellar medium or very young stars, indicating lithium is increasing. Identification of production sites is important for accounting for Li enhancement in the Universe and provides excellent insights into the internal working of stars. “

Early detection of Tropical cyclones has wide socio-economic implications. So far, remote sensing techniques have detected them the earliest. However, this detection was possible only after system developed as a well-marked low-pressure system over the warm ocean surface. A larger time gap between the detection and the impact of the cyclone could help preparation activities.

Prior to the formation of cyclonic system over the warm oceanic environment, the initial atmospheric instability mechanism, as well as the vortex development, is triggered at higher atmospheric levels. These cyclonic eddies are prominent features in the vertical atmospheric column encompassing the disturbance environment with a potential to induce and develop into a well-marked cyclonic depression over the warm ocean surface. They could be used for detection of prediction of cyclones

A team of Scientists including Jiya Albert, Bishnupriya Sahoo, and Prasad K. Bhaskaran from IIT Kharagpur, with support from the Department of Science & Technology, Government of India under the Climate Change Programme (CCP), devised a novel method using Eddy detection technique to investigate the formative stages and advance detection time of tropical cyclogenesis in the North Indian Ocean region. The research was published in the journal ‘Atmospheric Research’ recently.

The method developed by the scientists’ aims to identify initial traces of pre-cyclonic eddy vortices in the atmospheric column and track its Spatio-temporal evolution. They used coarser grid resolution of 27 km for identification and finer resolution of 9 km to evaluate the characteristics of eddy vortices. The study was conducted with cases of four post-monsoon severe cyclones –Phailin (2013), Vardah (2013), Gaja (2018), Madi (2013), and two pre-monsoon cyclones Mora (2017) and Aila (2009) that developed over North Indian Ocean.

The team observed that the method could bring about genesis of prediction with a minimum of four days (~ 90 h) lead time for cyclones developed during the pre-and post-monsoon seasons. Initiation mechanisms of genesis of tropical cyclones occurs at upper atmospheric levels and are also detected at higher lead time for pre-monsoon cases, unlike the post-monsoon cases. The study made a comprehensive investigation on the behavior of eddies in an atmospheric column for non-developing cases and compared these findings with developing cases.

The technique was found to have potential for early detection of tropical cyclogenesis in the atmospheric column prior to satellite detection over ocean surface.

Figure: Hovmöller diagram representing the shear and vorticity components of Okubo-Weiss Zeta Parameter (OWZP) for cyclones (a) Phailin, (b) Vardah, (c) Gaja, and (d) Madi corresponding to inner domain (9 km resolution). Blue marker represents atmospheric pre-cyclonic eddies detection using OWZP technique, and the red marker represents satellite detection of low-pressure over warm ocean surface.

Having found lithium excess to be common among the low mass Red Clump Giants, they have now traced helium-flashing phase of the star’s evolution as the site for high lithium production. This transition phase lasts for about 2 million years, during which Red Giant Branch (RGB) giantstars with inert helium-core at the centre become Red Clump Giant stars of helium-core burning.

Variation of lithium abundance with gravity mode period spacing in RC stars tracks the evolution of the stars and simulations of helium-flashing phase starting at the tip of RGB to RC phase

Recently, a group of astronomers at the Indian Institute of Astrophysics (IIA), Bengaluru, an autonomous institute of the Department of Science & Technology, Government of India, found observational evidence for lithium enhancement during the helium-flashing phase of 2 million years, followed by a rapid decrease in lithium abundances of such stars. According to their work, it seems the lithium excess in giants is a transient phenomenon.

The researchers led by Mr. Raghubar Singh and Prof. Eswar Reddy of IIA along with Simon Campbell of Monash University, Australia; Bharat Kumar of CAS, China;and MathieuVrard of Ohio State University, USA used asteroseismology (seismic study of stars using time-resolved photometry from Kepler Space Telescope) combined with spectroscopic abundances of elements to track the evolution of lithium in a sample of giant stars. In addition to the evidence for lithium production site, a first-of-its-kind correlation between the two independent observed quantities – lithium abundance and stellar oscillations (gravity mode period spacing) – will serve to track the helium-flashing phase of converting RGB giant of an inert, electron-degenerate helium-core into a fully convective helium-burning core by a series of core helium-flashes, a theory developed in the 1960s. This work is published in the ‘Astrophysical Journal Letters’.

Lead author Mr. Raghubar Singh said, “We do not have much insight into the helium-flash phase, let alone understanding of lithium production. These new results will inspire further observations as well as theoretical models.”

Talking about the importance of this result Prof. Reddy said, “These results will be of great interest to a larger community of theoreticians and observers. This is because of lithium’s broader implications to cosmological models, which predict Big Bang lithium abundance, which is a factor of four less than the presently observed values in the interstellar medium or very young stars, indicating lithium is increasing. Identification of production sites is important for accounting for lithium enhancement in the Universe and provides excellent insights into the internal working of stars.”

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Keywords: Science & Technology, Lithium, Helium, Flash Phase, Research, Innovation, Stars, Space, Research, Astrophysics, Neutrinos IIA, Bengaluru, Scientists, Nutrions, RGB Giants, Mechanism, 2 million Years, India, NASA, ISRO.

Galaxies like the one we reside in, the Milky Way, consist of discs containing stars, molecular and atomic hydrogen, and helium. The molecular hydrogen gas collapses on itself in distinct pockets, forming stars, its temperature was found to be low –close to 10 kelvin, or -263 ºC and thickness is about 60 to 240 light-years. The atomic hydrogen extends both above and below the discs.

However, more sensitive observations in the past two decades have surprised astronomers. They have estimated that molecular hydrogen extends farther from the disc in both directions, up to about 3000 light-years. This gaseous component is warmer than the one straddling the disc and has comparatively lesser densities, thus escaping earlier observations. They called it the ‘diffuse’ component of the molecular disc.

How much of the total molecular hydrogen is this diffuse component of the disc remains unclear. In a new study, a researcher from Raman Research Institute (RRI), Bengaluru, an autonomous organisation of the Department of Science and Technology (DST), Government of India, has carried out mathematical calculations on the computer and used publicly available astronomical data of a nearby galaxy to pin down the ratio of the narrow and diffuse gaseous components. The study, funded by the DST, Government of India, was published in the journal Monthly Notices of the Royal Astronomical Society.

“The molecular hydrogen gas converts to individual stars under the pull of gravity, thus holding clues to the star formation processes and the evolution of the galaxy,” said Narendra Nath Patra, the researcher. If a significant part of the gas extends beyond the thin disc of a few hundred light-years, it may explain why astronomers also observe stars at a few thousand light-years perpendicular to the galactic disc. It is also essential to understand why the gas has two components, he says, and maybe tell-tale signatures of supernovae or exploding stars.

For the study, Narendra focussed on a single galaxy about 20 million light-years away from the Milky Way. The distance is relatively small compared to the size of the universe, more than 10 billion light-years. The galaxy’s proximity makes it easier to observe with telescopes, and spectral lines of carbon monoxide (CO) are available for public research. “The carbon monoxide molecule is known to accurately trace molecular hydrogen, whose spectral lines are more difficult to observe,” explains Narendra. “The galaxy I chose is very much like the Milky Way and is therefore interesting for studying the ratio of diffuse and thin components of the disc,” he adds.

The researcher used the observed spectral lines of the CO molecule to infer the three-dimensional distribution of both the narrow disc component and the diffuse component of molecular hydrogen. Estimating how the ratio of the two components varies with the distance away from the centre of the galaxy, he found that the diffuse component makes up about 70 percent of the molecular hydrogen, and this fraction remains roughly constant along the radius of the disc. “This is the first time that such a calculation has been done for any galaxy,” he asserts.

The method, although new, relies on calculations that can be carried out on computers with the help of publicly available data. Hence, Narendra is already on his way to employing it on other nearby galaxies. “Currently, our group at RRI is employing the same strategy for a set of eight galaxies whose CO lines are available,” he says. “We want to test whether the results were one-off for the galaxy I chose or if there is a pattern,” he pointed out. The search is on, and we may expect the results this year.

Harikrishnan Aravindakshan, Prof. Amar Kakad, and Prof. Bharati Kakad from the Indian Institute of Geomagnetism (IIG), an autonomous institute under the Department of Science and Technology, have developed the theory. Prof. Peter Yoon of the University of Maryland, USA also joined the Indian scientists.

The theory solves every bit of uncertainty regarding the conflict between the observations from Magnetospheric Multiscale (MMS) Mission. It’s a NASA robotic space mission to study the Earth’s magnetosphere and theoretical predictions.

The scientists have developed a theory that helps understand the complicated nature of Sun-Earth interactions happening in the magnetosphere, the space around Earth that is controlled by the Earth’s magnetic field.

Using their theory, the scientists are now working towards a detailed study of the ion hole structures observed in various space and astrophysical environments.

They have completely ruled out the necessity of the upper limit in the temperature ratio between ions and electrons for generation of a special kind of wave called Bernstein Green Kruskal (BGK) waves, named after the scientists who predicted this wave. They revealed that the electrons that are not part of ion hole dynamics also play a vital role. The work has been published in the journal, Monthly Notices of the Royal Astronomical Society.

On 2 November 2017, NASA’s expedition to unlock Sun-Earth interaction’s complicated nature, the MMS spacecraft, observed negative monopolar potential, electric field potentials which can be visualized in the form of single-humped, pulse-type structures.

The scientific community suddenly recognized its importance, and several publications were presented. But none of the available theories could explain the characteristics of these structures due to the exotic background conditions.

The new theory developed by the IIG team now provides a better understanding of their characteristics and sheds light on the generation of these structures leading to the unravelling of nature’s greatest mystery that causes the phenomena, plasma transport and heating of plasma, the fourth state of matter after solid, liquid, and gas, which is the most natural and widely observed state of matter in the entire universe.

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Keywords: Science & Technology, Science, Discovery, Innovation, Invention, Matter, Galaxy, Plasma, Fourth Matter, Spacecraft, Space, IIG, Sun, Earth, Astronomy.

Signing of the MoU between ISRO and ARIES

The service centre called Aditya-L1 Support Cell (AL1SC), a joint effort of Indian Space Research Organisation (ISRO) and Aryabhatta Research Institute of Observational Sciences (ARIES) an autonomous institute of the Department of Science & Technology, Government of India will be used by the guest observers in analyzing science data and preparing science observing proposals.

AL1SC set up at the transit campus of ARIES at Haldwani, Uttarakhand, will jointly work with ISRO to maximize utilization of science data from Aditya-L1 and facilitate India’s first dedicated solar space mission- Aditya-L1.

The centre will act as conduit between the users (student and faculty members from research Institutes/ Universities/ Colleges etc.) and payload teams of Aditya-L1 and solar astronomy research community at large. It is slated to develop specific tools to assist guest observers/researchers to prepare observing proposals for Aditya-L1 observations and will assist ISRO with the design and development of the required analysis software for handling scientific data.

The centre will also provide the co-aligned data from other observatories around the world that can complement the data obtained from Aditya-L1 allowing users to accomplish the science goals beyond the capabilities of the Aditya-L1.

Combining data from other observatories will be helpful in building a solar features event knowledgebase which will be the compendium of different solar features seen on the surface of the Sun and in the heliosphere. This knowledge base will be immensely useful for the scientific community in connecting the features in heliosphere to the surface of the Sun.

In addition to this AL1SC will also build capacity by establishing periodic training of the national user community on data analysis and proposal preparation. Short workshops of 2-3 days durations at different locations in India will be held focusing on universities who do not have access for downloading and analyzing the Aditya-L1 data. Further, AL1SC has also planned to schedule frequent E-workshops and tutorials using online platforms.

The centre will expand reach of Aditya-L1 not only within India, but also increase the visibility of the mission at the international level. It will allow every interested individual to be able to perform scientific analysis of the data.