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BY PROF. F. E. OPARA OMOWA EDWARD ESAENWI SUDUM @ 2013 Astronomy Summer School

CAREERS IN ASTRONOMY: GRADUATE SCHOOL AND TEACHING

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CAREERS IN ASTRONOMY: GRADUATE SCHOOL AND TEACHING. BY PROF. F. E. OPARA OMOWA EDWARD ESAENWI SUDUM @ 2013 Astronomy Summer School. INTRODUCTION. - PowerPoint PPT Presentation

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Page 1: CAREERS IN ASTRONOMY:  GRADUATE SCHOOL AND               TEACHING

BYPROF. F. E. OPARA

OMOWA EDWARD ESAENWI SUDUM

@

2013 Astronomy Summer School

Page 2: CAREERS IN ASTRONOMY:  GRADUATE SCHOOL AND               TEACHING

Before I delve into the wide subject of careers in Astronomy, I will like to point out the difference between Astronomy and Astrology.

Astrology is a pseudo science that studies the planets and human behaviours. It is the study of the positions of the moon, Sun and other planets in the belief that their motions affect human beings. Astrologers claim that the positions of the heavenly bodies have an effect on the lives of human beings and events on Earth.

Astronomy on the other hand is the scientific study of the universe especially of the motions, positions, sizes, compositions and behaviour of astronomical objects.

Astronomy is real science, using mathematics, computers and complicated diagrams with specialized vocabulary, to study events in the universe; but astrologers do not follow the scientific method. Real scientists make careful measurements in well-controlled studies. Astrologers do not do experiments to prove their theories. Instead, they like to provide anecdotal evidence--stories people tell about how accurate they think astrology is. Anecdotal evidence is not acceptable in real science because it is too easy to leave out all the negative experiences people have, and people not very good at recalling and accurately reporting experiences exist.

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Studies in Astronomy and space science have led to many technological discoveries that are of great benefits to man today: some of these are:

Molyseal, a Non-toxic Coating for Aluminum NASA KSC sought to replace chromate-based coatings used on many of its spacecraft with safer

coatings because of its hazardous nature The KSC Materials Science Division, under a Small Business Innovation Research contract with Lynntech, of College Station, Texas., developed a molybdate-based con-version coating for aluminum and aluminum alloys. Referred to as Molyseal, the coating does not contain chemicals or materials that are hazardous or toxic nor does it raise health and safety concerns.. Industrial applications include aerospace, boilers, air conditioners and aluminum .

Super Insulation for Space Brought to Homes, Cars

Imagine your current refrigerator with expanded storage space but still the same size. This could be possible through the development of a super insulation blanket based on a space-age material called aerogel. For the refrigeration market, the product will allow thinner refrigerator walls, which will increase the refrigerated volume of the system. For the translucent panel and skylight market, the product will allow significant light transmissions with a fraction of the heat loss associated with the competing technologies. Other potential markets include household freezers and ovens; offshore oil well underwater pipelines; shipping containers; refractory insulation for automotive firewalls, floorboards, exhaust systems, automotive air intake, head liners and race cars; noise suppression panels for aircraft and acoustic damping insulation for buildings; head phones; and much more.

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DNA Analyzer – Cancer Detection DeviceTo help decipher the medical mystery of why and how microgravity affects the immune system, NASA sought development of a machine that could separate and examine cells rapidly. The DNA Analyzer allows better understanding of the nature of a patient’ s tumor, thereby enabling better treatment. Other potential uses of the new technology involve early detection of leukemia, chemo-sensitivity studies prior to chemotherapy, antibody analysis, and detection of pathogenic organisms.

Infrared Camera: A sensitive infrared hand-held camera that observes the blazing plumes from the Shuttle also is capable of scanning for fires. Designed by the Jet Propulsion Laboratory Center for Space Microelectronics in partnership with Amber, a Raytheon company, the camera can also be used for night vision and navigation. During the bush fires that ravaged Malibu, Calif., in 1996, the camera was used to point out hot spots for firefighters.

Jewelry Design Equipment: Jewelers no longer have to worry about inhaling dangerous asbestos fibers from the blocks they use as soldering bases. Space Shuttle heat shield tiles offer jewelers a safer soldering base with temperature resistance far beyond the 1,400 degrees F. generated by the jeweler’s torch.

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Other benefits of astronomy and space science include, as spin offs from the Apollo program include:

Kidney Dialysis: Dialysis machines were developed as a result of a NASA-developed chemical process to remove toxic waste from used dialysis fluid.

Physical Rehabilitation: A cardiovascular conditioner developed for astronauts in space led to the development of a physical therapy and athletic development machine used by football teams, sports clinics and medical rehabilitation centers.

Water Purification: The technology for purifying water, used on the Apollo spacecraft, now is used to kill bacteria, viruses and algae in community water supply systems and cooling towers. Also, filters mounted on faucets can reduce lead in water supplies.

Vacuum Metallizing Techniques: These led to an extensive line of commercial products, from insulated outer garments and packaging for foods, to wall coverings, window shades, life rafts, candy wrappings, reflective blankets and photographic reflectors.

Cordless Power Tools: A NASA requirement during the Apollo program, re-chargeable tools were developed to permit astronauts to do repairs in space.

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Laser Angioplasty: From laser technology for remote sensing of the ozone layer, Advanced Inter-dentinal Systems, Irvine, Calif., developed a cool laser that uses ultraviolet light energy to operate on human tissue.

Digital Cardiac Imaging (DCI) System: Designed by Phillips Medical Systems International, DCI uses image processing technology on a monitor of the heart’s regions, following a catheter as it moves. The technology was developed for NASA Earth remote-sensing satellites.

Digital Imaging Breast Biopsy System: Goddard Space Flight Center contracted with Scientific Imaging Technologies, Inc. (SITe) to develop a new advanced charge coupled device that could be manufactured at lower cost. SITe applied the NASA-driven enhancements to develop a technique called the LORAD Stereo Guide Breast Biopsy System, which incorporates SITe’s charge coupled device as part of a digital camera system that "sees" a breast structure with x-ray vision.

Artificial Heart: The technology used in Space Shuttle fuel pumps led to the development of a miniaturized ventricular assist pump by NASA and renowned heart surgeon Dr. Michael DeBakey. The tiny pump – two inches long, one inch in diameter and weighing less than four ounces – has been successfully implanted into more than 20 people.

Diagnostic Instrument: NASA technology was used to create a compact laboratory instrument for hospitals and doctors’ offices that more quickly analyzes blood, doing it in 30 seconds instead of 20 minutes.

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Bioreactor: Developed for Space Shuttle medical research, this rotating cell culture apparatus simulates some aspects of the space environment, or microgravity, on the ground. Tissue samples grown in the bioreactor are being used to design therapeutic drugs and antibodies. Some scientists believe the bioreactor will routinely produce human tissue for research and transplantation.

Infrared Thermometer: Infrared sensors developed to remotely measure the temperature of distant stars and planets led to the development of the hand-held optical sensor thermometer. Placed inside the ear canal, the thermometer provides an accurate reading in two seconds or less.

Lifesaving Light: Special lighting technology developed for plant growth experiments on Space Shuttle missions is now used to treat brain tumors in children. Doctors at the Medical College of Wisconsin in Milwaukee use light-emitting diodes in a treatment called photodynamic therapy, a form of chemotherapy, to kill cancerous tumors.

Prosthesis Material: Responding to a request from the orthopedic appliance industry, NASA recommended that the foam insulation used to protect the Shuttle’s external tank replace the heavy, fragile plaster used to produce master molds for prosthetics. The new material is light, virtually indestructible and easy to ship and store.

Insulation Pumps: Implantable and external insulin pumps, which are based on technology used on the Mars Viking spacecraft, have aided insulin-dependent diabetics. These computerized pumps can infuse insulin at a pre-programmed rate, allowing more precise control of blood sugar level and eliminating the need for daily injections.

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Because of the technology spin offs from Astronomy and space science studies over the years, Astronomers now do not only work as researchers in observatories and teachers in schools and colleges but have useful employments in information and communications technology (ICT) firms, Astrophotography institutions.

However, enthusiasm, quest for knowledge and the joy of sharing it with others are the greatest motivations for Astronomers. This explains why many Astronomers work as tutors in Institutes and colleges.

Another reason why Astronomers work mostly in the civil service is the fact that space research is capital intensive and only government can finance such a huge and daring venture.

A career in Astronomy must therefore be borne out of genuine interest in exploring our galaxy and the universe at large. An Astronomer or Space Scientist who excels in his chosen profession is an embodiment of knowledge and has relevance in every sphere of human endeavour.

Welcome to the world of Astronomy and Space science where man interacts with the uiverse.

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The Centre for Basic Space Science (CBSS) of National Space Research and Development Agency (NASRDA) has identified some abandoned telecommunications dishes which lie across the country. These dishes or Earth Stations were managed by the defunct Nigerian External Telecommunications (NET). The dishes are of different sizes and located at the places shown in the table below

 S/N

LOCATION DISH SIZE

1 ENUGU, ENUGU STATE 18M

2 KUJAMA, KADUNA STATE 32M

3 LANLATE, OYO STATE 30M

4 IKEJA, LAGOS 30M

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These earth stations have control rooms and administrative buildings, visitors’ buildings, generator houses and about 150m microwave transmitter towers. They served as digital earth stations used as V- SAT hub for international traffic and designed to operate at two frequencies: 6 and 4 GHz for up-link and down-link respectively, they play central roles in transoceanic communications across the Atlantic and Pacific Oceans, carrying phone call, data, internet and TV content across the Atlantic and Pacific oceans to Europe, America and Asia

  In line with the transformation agenda of the Federal

Government, NASRDA - Centre for Basic Space Science (CBSS), Nsukka is seeking for the release of these facilities for conversion to Space Science/Astronomy Research.

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The successful conversion of these satellite earth stations to astronomical observations for space science studies and research will offer the country the rare privilege of:

Hosting world class national facilities for education and research in astronomy and geodesy at about 1/10th the cost of building a new radio astronomy observatory.

Being part of the South African Square Kilometre Array (SKA) project.

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Manpower development: the conversion will enable the observatories train personnel in a number of fields such as electronics and electrical engineering, mechanical engineering, image processing and computer science etc. generally speaking, economic wealth creation is made through the development of people, be it through direct employment or training programmes or spin-off industries leading to direct employment.

Research and education: the establishment of a radio observatory under the supervision of NASRDA-CBSS will enable the introduction of Astronomy and space science in universities in Nigeria where there is none. It is worthy of note that advance in astronomy is synonymous with advance in technology.

Information and communication technology: the boost to nation’s information and communication industry is likely to be enormous. A radio astronomical observatory in Nigeria will result in significant increase in information and communication technology (ICT) penetration in the country.

Space geodesy programmes: precise space-based geodetic measurements from VLBI, Satellite Laser Ranger (SLR), Lunar Laser Ranger (LLR) and Global Navigation Satellite Systems (GNSS) are required for accurate referencing and the determination of the size, shape and gravity of the earth. Geodetic techniques are used to study geodynamic processes such as earth’s plate tectonic motions, postglacial rebounds or variations in earth rotation and orientation. It has made significant contributions to mapping, geo-referencing, engineering, surveying and sea level change studies

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The Square Kilometre Array Telescope (SKA) project will be the world’s biggest Telescope and one of the biggest scientific projects ever. It will be made up of many large antennas spread over 3000Km (and other types of radio receivers) that will be linked together via optic fibre cables. The total surface area of all the antennas together will add up to approximately one square kilometre giving 50 times the sensitivity and 10,000 times the survey speed of the best current day telescopes.

The SKA will be made up of three different kinds of receiving technologies The Mid-frequency dish array – which looks like DSTV dishes but much more bigger – will be about 15m in

diameter. Large, flat disk-shaped receivers – each about 60m wide (known as the dense aperture array) which will

operate at mid frequencies. Small upright radio receivers – about 1.5m high (known as the sparse aperture array) which will operate at

low frequencies. What will the SKA be used for? Radio Astronomers will use the SKA to understand how stars and galaxies formed and how they evolved

over time; what the so called “Dark matter” is that occupies 95% of the universe; how magnetic fields formed and evolved in the universe and how they influence astronomical processes, further insight into the invisible universe and the expectation of in extraterrestrial planets.

Scientists, Physicists and Astronomers will use it to investigate the validity of Einstein’s theory of relativity and perhaps detect life elsewhere in the universe.

The SKA will also be used to discover new aspects of the universe that we had not predicted and will generate more questions that need to be answered.

   

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When will the SKA be built? SKA Phase 1 construction is scheduled to begin in 2016 SKA Phase 2 Should be built from 2019 – 2024

Why Nigeria should join the partnership in the SKA project in South Africa Following the present construction of a 25m Nigeria Radio Telescope (NRT) in china and the design of

many radio astronomy telescopes (SRAT) in an array, the need for Nigeria to join the SKA project partnership in South Africa cannot be over emphasized:

The Consortium to bid for the SKA work packages are being proposed and Nigeria shall benefit from it by the involvement of Nigerian consultants, engineers and industrialists etc.

Europe’s leading Astronomers met in Brussels in September, 2012 to discuss funding opportunities for collaborative research between Africa and Europe. Hence, in 2012, the European Parliament adopted a declaration to promote science capacity building in Africa in light of the new radio astronomy research opportunities offered by SKA and Nigeria stands to gain.

It is expected that member organizations for this project especially developing nations like Nigeria will be supported to train more than 100 Scientists, 100 Engineers and Computer Scientists/Engineers up to PHD level and many more for M.SC and B.Sc in local and international higher institutions.

The great need to acquire radio astronomy signal processing and electronics research in-depth knowledge will greatly benefit CBSS and Nigeria stands to gain tremendously.

The SKA human capacity development programme which is planning to award bursaries and scholarships to partnership nations in Africa will greatly increase the number of Scientists and Engineers and hence enhance their quality.

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The tremendous amount of data that is expected to come out of the SKA project requires many experts applying their minds to the real world challenges of processing the massive data , hence Nigeria Radio Astronomers in CBSS and Nigerian universities will benefit immensely.

Following the construction of 64 dishes for SKA and another 190 dishes that will be added during phase 1 of the SKA from 2016, Nigeria stands to benefit in the acquisition of additional radio telescopes by the refurbishment of the existing abandoned radio communications dishes around the country and the building of more new ones.

Spin-offs expected from SKA can be of benefit to Nigeria. The technologies and systems of SKA will require Engineers to work at the cutting edge of design and innovation. Hence, there will certainly be technology spin-offs for more generic and commercial applications. For example, the SKA will collect and process significant amount of data which will require advances in high-performance computing; while producing thousands of antennas within short time scales that will lead to new manufacturing and construction techniques. The SKA project would drive developments in many technology areas including antennas, signal transport, signal processing, computing and data archiving. The most important spin-off however will be the generation of new knowledge and knowledge workers – young Scientists and Engineers with cutting edge skills and expertise in a wide range of scarce and innovative fields of Space Science and Technology. More than 1000 Nigerian Scientists and Engineers are expected to participate in these projects.

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To be a classic research astronomer who runs a telescope, analyzes data, and publishes papers, you will need a PhD degree. The same is obtainable for a college astronomy professor.

Support positions in astronomy—for example, a telescope operator, observer, or software developer—typically require a Bachelor’s or Master’s degree

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Astronomy has 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 anthropologicalevidence. 

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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. 

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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.

Forensic Astronomy which is using methods from astronomy to solve problems of law and history. 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.

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Astronomers were among the first to embrace computers (both professionally and personally) back in the 1950s and 60s, and the typical astronomer today spends hours a day at a computer screen analyzing data, controlling

and monitoring telescopes, writing papers, reading journal articles, or researching databases.

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Engineers continually push the capability and

applicability of computers and other tools in Astronomy. They embed computers in other machines and

systems, build networks to transfer data, and develop ways to make computers faster, smaller, and more capable

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Cyber security Networking Design automation Machine intelligence Computer software Biomedical Embedded Systems

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The SKA radio telescope is not only physically large, but also complex and comprised millions of different parts. The designers of these parts need to know how they will be used and how they will fit together. This is where System Engineering comes in – it is a formal way to ensure that the hardware and software is fit for purpose and is value for money

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Processing the vast quantities of data produced by the SKA will require very high performance central supercomputers capable of 100 petaflops per second processing power. This is about 50 times more powerful than the most powerful supercomputer in 2013 and equivalent to the processing power of about one hundred million PCs

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ESAENWI SUDUM

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Astrophotography is a specialized type of photography that entails recording images of astronomical objects and large areas of the night sky.

The development of astrophotography as a scientific tool was pioneered in the mid-19th century by experimenters and amateur astronomers

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The first known attempt at astronomical photography was by Louis Jacques Mandé Daguerre, who invented the daguerreotype (An early photographic process with the image made on a light-sensitive silver-coated metallic plate) and attempted in 1839 to photograph the moon. 

 John William Draper, New York University Professor of Chemistry, physician and scientific experimenter managed to make the first successful photograph of the moon a year later on March 23, 1840, taking a 20-minute-long daguerreotype image using a 5-inch (13 cm) reflecting telescope

The Sun may have been first photographed in an 1845 daguerreotype by the French physicists Léon Foucault and Hippolyte Fizeau.

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The first photograph of a star was a daguerreotype of the star Vega (the brightest star in the constellation Lyra )by astronomer William Cranch Bond and daguerreotype photographer and experimenter John Adams Whipple, on July 16 and 17, 1850 with Harvard College Observatory's 15 inch Great refractor.

Sir William Huggins and his wife Margaret Lindsay Huggins, in 1876, used the dry plate process to record the spectra of astronomical objects.

In 1883, an amateur astronomer Andrew Ainslie Common used the dry plate process to record several images of the same nebula in exposures up to 60 minutes with a 36-inch (91 cm) reflecting telescope that he constructed in the backyard of his home in Ealing, outside London. 

In the 1970s after the invention of the CCD, photographic plates have given way to electronic imaging in professional observatories. CCD's are far more light sensitive, do not drop off in sensitivity to light over long exposures the way film does, have the ability to record in a much wider spectral range, and simplify storage of information.

The late 20th century have seen advances in astronomical imaging in the form of new hardware, with the construction of giant multi-mirror and segmented mirror telescopes. It has also seen the introduction of space based telescopes, such as the Hubble Space Telescope.

A CCD (charge-coupled device) is an electronic instrument for detecting light. 

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A New Way to PhotographOne of the biggest advances in amateur astronomy in the last few years has been the advent of inexpensive and easy-to-use CCD imaging systems.  With one-shot-color cameras, computerized telescopes, and full-featured image processing software.  In fact, taking color images of deep-sky objects is now so easy and fast that it is practically an extension of observing.  An amateur astronomer with an 8" telescope and CCD camera can capture images in just 30 seconds that surpass the view seen through the eyepiece of a 30" telescope.Also, CCDs allow deep-sky observing from light-polluted skies.  As more of the world lights up at night, finding a dark observing site gets harder and harder.  But CCDs can cut through the light pollution to some extent, and the light pollution can be digitally subtracted from the image.  Also, narrowband filters can easily be used to block even more skyglow.

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Astronomical photography is one of the earliest types of scientific photography and almost from its inception it diversified into subdisciplines that each have a specific goal including Celestial cartography, astrometry, stellar classification, photometry, spectroscopy, polarimetry, and the discovery of astronomical objects such as asteroids, meteors, comets, variable stars, novae, and even unknown planets. These all require specialized equipment such as telescopes designed for precise imaging.

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This is the fringe of astronomy and branch of cartography concerned with mapping stars, galaxies, and other astronomical objects on the celestial sphere.

Measuring the position and light of charted objects requires a variety of instruments and techniques. These techniques have developed from angle measurements with quadrants and the unaided eye, through sextants combined with lenses for light magnification, up to current methods which include computer automated space telescopes.

Uranographers have historically produced planetary position tables, star tables and star maps for use by both amateur and professional astronomers.

More recently computerized star maps have been compiled, and automated positioning of telescopes is accomplished using databases of stars and other astronomical objects.

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Is the branch of astronomy that involves precise measurements of the positions and movements of stars and other celestial bodies. The information obtained by astrometric measurements provides information on the kinematics and physical origin of our Solar System and our galaxy, the Milky Way.

astrometry is also fundamental for fields like celestial mechanics, stellar dynamics and galactic astronomy. In observational astronomy, astrometric techniques help identify stellar objects by their unique motions. It is instrumental for keeping time, in that UTC (Coordinated Universal Time) is basically the atomic time synchronized to Earth's rotation by means of exact observations.

Astrometry is an important step in the cosmic distance ladder because it establishes parallax distance estimates for stars in the Milky Way.

Astrometry has also been used to support claims of extrasolar planet detection by measuring the displacement the proposed planets cause in their parent star's apparent position on the sky, due to their mutual orbit around the center of mass of the system. 

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This is a technique of astronomy concerned with measuring the flux, or intensity of an astronomical object's electromagnetic radiation. Usually, photometry refers to measurement over large wavelength bands of radiation; when not only the amount of radiation but also its spectral distribution are measured the term spectrophotometry is used.

Photometric measurements can be combined with the inverse-square law to determine the luminosity of an object if its distance can be determined, or its distance if its luminosity is known.

Other physical properties of an object, such as its temperature or chemical composition, may be determined via broad or narrow-band spectrophotometry.

Photometry is also used to study the light variations of objects such as variable stars, minor planets, active galactic nuclei and supernovae, or to detect transiting extrasolar planets.

Measurements of these variations can be used, for example, to determine the orbital period and the radii of the members of an eclipsing binary star system, the rotation period of a minor planet or a star, or the total energy output of a supernova.

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This is the study of the interaction between matter and radiated energy. Historically, spectroscopy originated through the study of visible light dispersed according to its wavelength, e.g., by a prism Later the concept was expanded greatly to comprise any interaction with radiative energy as a function of its wavelength or frequency. Spectroscopic data is often represented by a spectrum, a plot of the response of interest as a function of wavelength or frequency.

Spectroscopy and spectrography are terms used to refer to the measurement of radiation intensity as a function of wavelength and are often used to describe experimental spectroscopic methods. Spectral measurement devices are referred to as spectrometers, spectrophotometers, spectrographs or spectral analyzers.

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This is the measurement and interpretation of the polarization of transverse waves, most notably electromagnetic waves, such as radio or light waves. Typically polarimetry is done on electromagnetic waves that have traveled through or have been reflected, refracted, or diffracted by some material in order to characterize that object.

Polarimetry is used in remote sensing applications, such as planetary science and weather radar.

Polarimetry can also be included in computational analysis of waves. For example, radars often consider wave polarization in post-processing to improve the characterization of the targets.

In this case, polarimetry can be used to estimate the fine texture of a material, help resolve the orientation of small structures in the target, and, when circularly-polarized antennas are used, resolve the number of bounces of the received signal (the chirality of circularly polarized waves alternates with each reflection).

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