What is Astronomy

Astronomy is a branch of science that involves observing celestial bodies (such as stars, planets, comets, nebulae, star clusters or galaxies) and natural phenomena that occur outside the Earth’s atmosphere (such as radiation). cosmic background (CMB radiation)). Science studies different sides of the basic celestial bodies – such as their origin, physical/chemical properties, meteorology, and motion – and how knowledge about these objects explains the formation and expansion of the universe.

Astronomy as a science is one of the oldest, as is known from astronomical artifacts dating back to prehistoric times; for example, monuments of Egypt and Nubia, or Stonehenge in England. People from several types of early civilizations of Babylon, Greece, China, India, and Maya have also been found to have made methodological observations of the night sky. But despite having a long history, astronomy was able to develop into a modern branch of science through the invention of the telescope.

Kinds of Astronomy

1. Observational astronomy
2. Radio astronomy
3. Infrared astronomy
4. Optical astronomy
5. Ultraviolet astronomy
6. X-ray astronomy
7. Gamma-ray astronomy
8. Theoretical astronomy

1. Observational astronomy

As is well known, astronomy requires information about celestial bodies, and the main source of most information by far is electromagnetic radiation, or more specifically, visible light. Astronomical observations can be divided according to the region of the electromagnetic spectrum that is observed: part of the spectrum can be observed through the Earth’s surface, while other parts can only be reached from a certain height, or even only from space. Detailed information about the division can be seen below:

2. Radio astronomy

This type of observational astronomy observes radiation with wavelengths greater than one millimeter (approximate). In contrast to other species, this type of observational astronomy observes radio waves can be treated as waves instead of discrete photons. Thus phase and amplitude measurements are relatively easy compared to shorter wavelengths.

3. Infrared astronomy

Infrared astronomy along with analysis involves the detection of infrared radiation (radiation in which the wavelength exceeds red light). Most types of radiation are absorbed by Earth’s atmosphere, except that the wavelengths do not differ too much from visible red light. Therefore infrared radiation, which will be observed in observatories that will be built in high places and not humid, or even in space.

4. Optical astronomy

The Subaru Telescope and the Keck Observatory on Mauna Kea, are both examples of observatories that can observe either the visible or the near-infrared. On the right is the NASA Infrared Telescope Facility, which operates only at near-infrared wavelengths.

Also known as visible light astronomy, optical astronomy observes electromagnetic radiation that is visible to the human naked eye. Therefore, the oldest branch, because it does not require equipment. Starting from the late 19th century until about a century later, photographic techniques used astronomical optical images, but before that they had to be drawn by hand.

5. Ultraviolet astronomy

Electromagnetic radiation is ultraviolet with a wavelength of about 100 to 3,200 (10-320 nm). The length of light that is absorbed by Earth’s atmosphere, so to observe must be made of the upper atmosphere, or outer atmosphere (space). Type Astronomy is suitable for studying the thermal radiation and spectral emission lines of blue stars for very high temperatures (classification OB), because stars as ultraviolet radiation are very bright – these studies are often carried out and include stars located in other galaxies.

6. X-ray astronomy

Objects can emit light of the X-ray wavelength through synchrotron emission (derived from electrons rotating around a magnetic field) or through the emission of thermally dense gases and dilute gases in 107 X-K rays. It is also absorbed by the atmosphere, so observations must be made from above a balloon, rocket, or research satellite. X-ray sources include X-rays of binary stars (binary X-rays), pulsars, supernova remnants, elliptical galaxies, galaxy clusters, and active galactic nuclei.

7. Gamma-ray astronomy

Gamma-ray astronomy studies astronomical objects at the shortest wavelengths (gamma-rays). Gamma rays can be observed directly by satellites such as the Compton Gamma-Ray Observatory (CGRO), or by a special type of telescope called the Cherenkov telescope (IACT). This type of telescope doesn’t actually detect gamma rays but is capable of detecting visible light sparks that result from the absorption of gamma rays by the atmosphere.

8. Theoretical astronomy

There are many different types of methods and tools that theoretical astronomers can use, including other analytical models (eg, to predict the behavior of polytropic stars) and computational numerical simulations; each with its own advantages. Analytical models are generally better if the researcher wants to know the problem and observe what happens to the rows; Numerical models can reveal the existence of phenomena and effects that are not easily seen.

Interdisciplinary research

Astronomy and astrophysics have floated strong links with these branches of science. Archeoastronomy example, the study of ancient or traditional astronomy in the context of their respective cultures using archaeological and anthropological evidence. Or astrobiology, this time studying the birth and development of biological systems in the universe; especially on the topic of life on other planets.

Specific Branches of Astronomy

1. Solar astronomy
2. planetary science
3. Star astronomy
4. Galactic astronomy
5. Extragalactic astronomy
6. Cosmology
7. Astronomy major

1. Solar astronomy

The sun is the closest star to Earth at about 8 light minutes, and is the most studied; it is a dwarf star in the main classification of the order G2 V, and is about 4.6 billion years old. While not to the level of a variable star, the Sun undergoes slight changes in its light through activity known as the sunspot cycle – fluctuations in the number of sunspots over the past eleven years. Sunspots are areas with lower temperatures and greater magnetic activity.

2. Planetary science

This branch of astronomy examines the arrangement of planets, moons, dwarf planets, comets, asteroids and other celestial bodies that revolve around stars, especially the sun, although this science also includes exoplanets. Our solar system has been studied in depth-first through telescopes and later using spacecraft – so understanding of the formation and evolution of planetary systems is already very good, although there are still new discoveries going on.

3. Star astronomy

Ant Nebula. The gas emitted from the dying star in the center is unusual in that it forms a symmetrical pattern, not chaotic like a typical explosion.

To understand the universe, the study of stars and how they evolve is fundamental. Astrophysics with respect to the stars themselves can be known through observational and theoretical terms, and also through computer simulations.

4. Galactic astronomy

Our solar system circulating in the Milky Way, spiral galaxy is banned in the Local Group. He is one of the most prominent in the galaxy cluster. The Milky Way spins material gas, dust, stars, and other objects, they all come together because of the gravitational pull. Earth itself lies in the dusty outer arm of the galaxy, so much of the Milky Way is invisible.

5. Extragalactic astronomy

The image above shows some blue circle objects; This is an image of the same galaxy, reproduced by the gravitational lensing effect caused by the yellow galaxy cluster in the center of the photo. A lens effect is generated and the gravitational field of the cluster bends the light so that the image of distant objects is enlarged and distorted.

6. Cosmology

Cosmology, derived from the Greek words kosmos (κόσμος, “world”) and the suffix -logia logo (λόγος, “study”) can be understood as an attempt to study the universe as a whole.

7. Astronomy major

Astronomy majors study the stars, planets and space. But in general, astronomy is better known from the beauty of the sky photos produced by both astronomers and amateur astronomers. Moreover, with the presence of a space telescope, the photos from space presented are even more amazing.