Astronomy is one of the oldest sciences. Prehistoric cultures left behind astronomical artifacts such as the Egyptian monuments and Stonehenge, and early civilizations such as the Babylonians, Greeks, Chinese, and Indians performed methodical observations of the night sky. However, the invention of the telescope was required before astronomy was able to develop into a modern science. Historically, astronomy has included disciplines as diverse as astrometry, celestial navigation, observational astronomy, the making of calendars, and even astrology, but professional astronomy is nowadays often considered to be synonymous with astrophysics.
During the 20th century, the field of professional astronomy split into observational and theoretical branches. Observational astronomy is focused on acquiring data from observations of celestial objects, which is then analyzed using basic principles of physics. Theoretical astronomy is oriented towards the development of computer or analytical models to describe astronomical objects and phenomena. The two fields complement each other, with theoretical astronomy seeking to explain the observational results, and observations being used to confirm theoretical results.
Amateur astronomers have contributed to many important astronomical discoveries, and astronomy is one of the few sciences where amateurs can still play an active role, especially in the discovery and observation of transient phenomena.
Ancient astronomy is not to be confused with astrology, the belief system which claims that human affairs are correlated with the positions of celestial objects. Although the two fields share a common origin and a part of their methods (namely, the use of ephemerides), they are distinct
Radio astronomy
Radio astronomy studies radiation with wavelengths greater than approximately one millimeter. Radio astronomy is different from most other forms of observational astronomy in that the observed radio waves can be treated as waves rather than as discrete photons. Hence, it is relatively easier to measure both the amplitude and phase of radio waves, whereas this is not as easily done at shorter wavelengths.
Although some radio waves are produced by astronomical objects in the form of thermal emission, most of the radio emission that is observed from Earth is seen in the form of synchrotron radiation, which is produced when electrons oscillate around magnetic fields.Additionally, a number of spectral lines produced by interstellar gas, notably the hydrogen spectral line at 21 cm, are observable at radio wavelengths.
A wide variety of objects are observable at radio wavelengths, including supernovae, interstellar gas, pulsars, and active galactic nuclei.
Interdisciplinary studies
Astronomy and astrophysics have developed significant interdisciplinary links with other major scientific fields. Archaeoastronomy is the study of ancient or traditional astronomies in their cultural context, utilizing archaeological and anthropological evidence. Astrobiology is the study of the advent and evolution of biological systems in the universe, with particular emphasis on the possibility of non-terrestrial life.
The study of chemicals found in space, including their formation, interaction and destruction, is called astrochemistry. These substances are usually found in molecular clouds, although they may also appear in low temperature stars, brown dwarfs and planets. Cosmochemistry is the study of the chemicals found within the Solar System, including the origins of the elements and variations in the isotope ratios. Both of these fields represent an overlap of the disciplines of astronomy and chemistry. As "forensic astronomy", finally, methods from astronomy have been used to solve problems of law and history.
Career In Astronomy
Astronomy is the science which deals with the study of heavenly bodies. It considers
(a) their motions, both real and apparent, and the laws which govern those motions;
(b) their forms, dimensions, masses, and surface features;
(c) their nature, constitution, and physical condition;
(d) the effects which they produce upon one another by their attractions and radiations;
(e) their probable past history and future development.
Astronomy is necessarily an observational science rather than an experimental one. The discussions and interpretation of observations employs the use of mathematical analysis, often of the most advanced type. Celestial bodies and celestial environment provide natural laboratories for studying physical phenomena in extreme conditions which are seldom realised in our terrestrial environment.Physical and mathematical theories are thus stretched to the limit to provide explanations for the celestial phenomena that we observe.
Modern astronomy requires the use of most modern and advanced technologies, e.g. in fabrication of modern telescopes, in buildingimaging and spectrscopic equipment to observe and analyse radiation received from the celestial objects. It needs fast computers, state-of-the-art software to handle data and process images, it needs stable space platforms to observe radiation otherwise blocked by the Earth's atmosphere.
Job Opportunities & Career Prospects
An acute need for young scientists in the field of Astronomy is present. The following possibilities are open for a career for a physics / mathematics / engineering graduate with a specialization or a Ph.D. in Astronomy & Astrophysics
* Research Scientist
Several research institutes and government organizations employ research scientists in various academic grades for research oriented programmes.
* University Faculty
There will be more openings in the universities, especially in physics departments, for specialists in Astronomy & Astrophysics
* Industry
Experience with sophisticated astronomical instrumentation and the expertise gained in computer programming and handling data can serve as valubale assets for jobs in industry
Requirements for a Career in Astronomy & Astrophysics
Astronomy & Astrophysics may be taught as a special course in the M.Sc. programmes of the physics departments in the universities or colleges. It is desirable for a student to acquire proficiency in physics and mathematics at the graduate level and then to Astronomy & Astrophysics specialization. An engineer with a B.Tech or B.E. degree, with an aptitude for Astronomy and Astrophysics, can also enter the field as a research scholar.
Though it is not necessary to undergo any formal training in Astronomy and Astrophysics at the undergraduate level, it helps the student to develop a general interest in the field, from reading good popular books or as an amateur astronomer. Research Scholars are expected to undergo one year course work in various subjects including Foundations of Classical & Quantum Physics, Mathematical Techniques, Numerical Analysis & Computing, besides introductory courses in Astronomy & Astrophysics. A good Ph.D. programme takes about four years to complete.
Teaching & Research Programmes
Opportunities for Astronomy & Astrophysics study are available in the universities and autonomous research institutions.
* Universities that offer Astronomy & Astrophysics specialization at M.Sc., and in some cases, a Ph.D. programme are
Punjabi University, Patiala, Osmania University - Full M.Sc. Course in Astronomy & Astrophysics, Aligarh Muslim University (AMU), Allahabad, Bangalore, Burdwan, Kolkata, Delhi, Gauhati, Gorakhpur, Gujarat, Indian Institute of Science, Jadavpur, Kashmir, Kumaon, Lucknow, Madurai Kamaraj University, Mahatma Gandhi University, Kottayam, Pune, Punjab, Pandit Ravi Shankar Shukla University, Roorkee, Swami Ramanand Teerth University, Nanded.
* Indian Institute of Astrophysics (IIA)
IIA has a full-time Ph.D. programme for which the students are selected through an entrance exam, followed by an interview. The exam is conducted in November every year and the is advertised around September. Students are also selected through Joint Entrance Screening Test, conducted annually in the month of February, followed by an interview. The advertisement appears in all leading newspapers. Posters are sent to various institutions, universities and colleges all over India. Highly motivated candidates with a M.Sc. degree in Physics / Maths or M.Tech. in Engineering & exceptional candidates with B.E. /B.Tech. degree and a good background in physics are eligible to apply for admission to the Ph.D. programme.
* Inter-University Centre for Astronomy & Astrophysics (IUCAA)
IUCAA has a regular Ph.D. programme for which applications are invited every spring from students who either possess an M.Sc. in Physics / Applied Mathematics / Astronomy / Computer Science or a Bachelor's or Master's degree in engineering or technology with adequate background in physics and mathematics or are expected to qualify for these degrees. Selection is made in July through a written test and an interview. Selected candidate is required to clear the CSIR / UGC-NET / GATE exam within one year of admission to the Ph.D. if he/she has not done so already.
* Joint Entrance Screening Test (JEST)
Joint Entrance Screening Test (JEST) is conducted at an all India level every year in the month of February for admission to Ph.D. programme. The advertisement appears in all the leading newspapers and posters are sent to various institutions, colleges, universities all over India inviting applications. The institutions participating in this programme are : Harish- Chandra Research Institute (Formerly Mehta Research Institute of Mathematics & Mathematical Physics); Indian Institute of Astrophysics (IIA), Bangalore; Institute of Physics (IOP), Bhubhaneswar; Institute for Plasma Research (IPR), Gandhinagar; Inter-University Centre for Astronomy & Astrophysics (IUCAA), Pune; Inter-University Consortium for DAE Facilities (IUC-DAEF), Indore; Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Bangalore; National Centre for Biological Sciences (NCBS), Tata Institute of Fundamental Research, Bangalore; National Centre for Radio Astrophysics (NCRA), Tata Institute of Fundamental Research, Pune; Physical Research Laboratory (PRL), Ahmedabad; Raman Research Institute (RRI), Bangalore; S N Bose Centre for Basic Natural Sciences (SNBNCBS), Kolkata; The Institute of Mathematical Sciences (IMSc.), Chennai. The pattern for JEST exam consists of multiple choice objective-type questions, with negetive marks for wrong answers. Candidates who are successful in the entrance exam are called for an interview and depending upon their performance, are selected as Junior Research Fellows for Ph.D. programme.
* Joint Astronomy Programme
This course is of one year duration, conducted at Indian Institute of Science (IISc.), Bangalore, jointly by IISc., IIA, RRI, TIFR. M.Sc., B.E., & B.Tech. degree holders are invited to apply in the spring of the year for selection in July through an interview. After the completion of the course, candidates are offered the opportunity for completing their Ph.D. at one of the participating institute.
* Autonomous Research Institutes
These offer a Ph.D. programme after a selection through interviews, usually in July every year. Advertisements appear in spring. The institutions are : RRI, NCRA, TIFR, PRL, UPSO, ISRO.
For details on "Career in Astronomy", please visit http://www.iucaa.ernet.in/~scipop/beastronomer.html
No comments:
Post a Comment