Please wait, while we are loading the content...
Please wait, while we are loading the content...
Content Provider | AstroPix |
---|---|
Description | Fifty years ago, astronomers discovered a mystery. They called it Loop I. Today, we still have not fully resolved the mystery of how this giant celestial structure formed but we do now have the best image of it, thanks to ESAs Planck satellite. Loop I is a nearly circular formation that covers one third of the sky. In reality, it is probably a spherical bubble that stretches to more than 100 across, making it wider than 200 full Moons. Its absolute size, however, is extremely uncertain because astronomers do not know how close it is to us: estimates to the centre of the bubble vary from 400 light-years to 25 000 light-years. What they do know is that the structure shows up in many different wavelengths, from radio waves to gamma rays. Planck sees Loop I in microwaves. This images colours reflect the polarisation the direction in which the microwaves are oscillating. Our eyes are not sensitive to this information in the visible light, where we perceive only the intensity and colour. Planck, however, can detect all three of these characteristics in the microwaves it targets. The microwaves detected by Planck are emitted by electrons that are being accelerated by the Galaxys magnetic field. Loop I is most visible in the skys northern hemisphere. Astronomers refer to this portion as the north polar spur. It can be seen in this image as the yellow arc. This fades to purple and can be traced into the southern hemisphere, completing the circle. The blue band spanning the image horizontally is the Galactic Plane. The most popular interpretation places Loop I close to us. If this is correct, it could be related to the ScorpiusCentaurus OB Association, a region of high-mass star formation that has been active for over 10 million years. Loop I could well be a supernova remnant, a giant bubble hollowed out by the explosion of stars in the OB association. It is likely that the stars responsible for Loop I have long since dispersed, so what we see is the smoke rather than the fire of the explosions. High-mass stars burn their nuclear fuel so quickly that they live only a few million years before exploding. As these titanic supernovas bloom, their blast waves carve bubbles in the surrounding gas. This compresses the Galaxys magnetic field into the bubble walls, making it stronger and more efficient at accelerating the electrons to produce the observed radiation. Loop I could well be the combined super-bubble from a number of such cataclysms. As the electrons lose energy and diffuse into the wider Galaxy, so Loop I will eventually fade and disappear. This is likely to take a few million years. If the loop is more distant, then it could conceivably be the result of an outburst from around the black hole at the centre of the Galaxy. |
File Format | TIF / TIFF |
Language | English |
Publisher Date | 2018-06-20 |
Access Restriction | Open |
Subject Keyword | Cosmology Morphology Cosmic Background |
Content Type | Image |
Educational Role | Student Teacher |
Educational Use | Self Learning Classroom |
Education Level | Any Level/Generic |
Resource Type | Photograph |
Subject | Physics |
National Digital Library of India (NDLI) is a virtual repository of learning resources which is not just a repository with search/browse facilities but provides a host of services for the learner community. It is sponsored and mentored by Ministry of Education, Government of India, through its National Mission on Education through Information and Communication Technology (NMEICT). Filtered and federated searching is employed to facilitate focused searching so that learners can find the right resource with least effort and in minimum time. NDLI provides user group-specific services such as Examination Preparatory for School and College students and job aspirants. Services for Researchers and general learners are also provided. NDLI is designed to hold content of any language and provides interface support for 10 most widely used Indian languages. It is built to provide support for all academic levels including researchers and life-long learners, all disciplines, all popular forms of access devices and differently-abled learners. It is designed to enable people to learn and prepare from best practices from all over the world and to facilitate researchers to perform inter-linked exploration from multiple sources. It is developed, operated and maintained from Indian Institute of Technology Kharagpur.
Learn more about this project from here.
NDLI is a conglomeration of freely available or institutionally contributed or donated or publisher managed contents. Almost all these contents are hosted and accessed from respective sources. The responsibility for authenticity, relevance, completeness, accuracy, reliability and suitability of these contents rests with the respective organization and NDLI has no responsibility or liability for these. Every effort is made to keep the NDLI portal up and running smoothly unless there are some unavoidable technical issues.
Ministry of Education, through its National Mission on Education through Information and Communication Technology (NMEICT), has sponsored and funded the National Digital Library of India (NDLI) project.
Sl. | Authority | Responsibilities | Communication Details |
---|---|---|---|
1 | Ministry of Education (GoI), Department of Higher Education |
Sanctioning Authority | https://www.education.gov.in/ict-initiatives |
2 | Indian Institute of Technology Kharagpur | Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project | https://www.iitkgp.ac.in |
3 | National Digital Library of India Office, Indian Institute of Technology Kharagpur | The administrative and infrastructural headquarters of the project | Dr. B. Sutradhar bsutra@ndl.gov.in |
4 | Project PI / Joint PI | Principal Investigator and Joint Principal Investigators of the project |
Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon |
5 | Website/Portal (Helpdesk) | Queries regarding NDLI and its services | support@ndl.gov.in |
6 | Contents and Copyright Issues | Queries related to content curation and copyright issues | content@ndl.gov.in |
7 | National Digital Library of India Club (NDLI Club) | Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach | clubsupport@ndl.gov.in |
8 | Digital Preservation Centre (DPC) | Assistance with digitizing and archiving copyright-free printed books | dpc@ndl.gov.in |
9 | IDR Setup or Support | Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops | idr@ndl.gov.in |