What is an Astronomer?

The study of astronomy is the oldest of the natural sciences. It is the only science in which you can study and observe physics at work throughout the whole universe, and yet not physically be able to touch what is being studied. Interestingly, it was the invention of the telescope that enabled astronomy to develop into a modern science.

An astronomer is a scientist who focuses primarily on the study of space, which includes the stars, the planets and the galaxies above us. The evolution of stars is also studied so as to understand how the sun and our solar system of planets were created and what will happen to them as they age. An astronomer will spend his or her time analyzing data, writing research papers, or creating computer programs that allow a more effective search for the data collected.

What does an Astronomer do?

An astronomer focuses primarily on the study of space, which includes the stars, the planets and the galaxies above us.

Astronomers study our own solar system, as well as other solar systems, stars, and galaxies. The bulk of an astronomer's job is heavily based on research, as the focus is on understanding how the universe works, and on trying to discover things about the universe that would be considered scientific breakthroughs.

The main tools used by astronomers are:

Telescopes - used to gather light emissions
Spectrographs - used to break up light into a spectrum to tell the temperature, composition, and velocity of space objects
Cameras - are connected to telescopes and used to gather images
Spacecrafts - cameras and telescopes are placed onboard to collect images of space objects
Computers - used to analyze data received from telescopes and spacecraft

Astronomers use all these tools quite often, especially telescopes (along with applying a lot of physics and mathematics. They are able to use a variety of telescopes to observe objects in the Universe - some of these telescopes are located here on planet earth and some are sent into space. Only the very closest planets (all within our Solar System) can be reached by spacecraft. Therefore, telescopes or earth-orbiting satellites are relied upon to indirectly give us information about all other celestial objects by observing light emitted or reflected from them. Telescopes gather light from distant objects and let us see them "up close." It is through the collection and detailed analysis of this light that astronomers are able to unlock some of the many mysteries of the Universe. If fact, the main purpose of using a telescope is to collect this light so the astronomer can analyze and interpret this data.

An example of a telescope astronomers use is The Hubble Space Telescope. It can see out to a distance of several billions of light-years (a light-year is the distance that light travels in one year, about 5,865,696,000,000 miles). The farthest that the Hubble Space Telescope has seen so far is about 10-15 billion light-years away. Several of the Hubble Deep Field galaxies that astronomers are able to see are as they were billions of years ago, because this is how long it took for their light to reach us.

There are different fields of astronomy, and most astronomers will choose to focus on only one. Some examples of these fields are solar astronomy, planetary astronomy, stellar astronomy, galactic astronomy, extragalactic astronomy, and cosmology. Each field then branches into an observational or theoretical type of study. The observational branch uses the basic principles of physics and is focused on acquiring and analyzing data. The theoretical branch, on the other hand, describes astronomical objects and phenomena through the development of computer or analytical models. The two branches go hand-in-hand, with theoretical astronomy focusing on explaining the observational results, and observational astronomy being used to confirm theoretical results.

Astronomy can also be divided according to its links with other branches of science, as it can apply physics, biology and geology to explain the origin and evolution of space, stars and celestial bodies. Those four sub-fields are: astrophysics, astrometry, astrogeology, and astrobiology.

Are you suited to be an astronomer?

Astronomers have distinct personalities. They tend to be investigative individuals, which means they’re intellectual, introspective, and inquisitive. They are curious, methodical, rational, analytical, and logical. Some of them are also artistic, meaning they’re creative, intuitive, sensitive, articulate, and expressive.

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What is the workplace of an Astronomer like?

Workplaces for astronomers can vary. Typical classroom settings are common for those who teach. Oftentimes, astronomers are invited to give individual talks at other institutions. Most universities (with Astronomy departments) hold weekly meetings where they bring in scientists from other universities to talk about their research. Observatories are also typical workplaces and provide astronomers with labs. The ultimate goal for any astronomer, however, is almost certainly a career at NASA. NASA is a United States government agency that is responsible for science and technology related to air and space.

Working in an office usually involves doing administrative work or working on research. Research could mean a wide variety of things, such as calibrating and analyzing data, to running numerical models, or testing theories. Much time is spent in front of a computer, therefore familiarity with computers and programming is a necessity in this career.

Traveling involves going to several conferences every year, which are held all across the world. For example, the AAS (American Astronomical Society) and IAU (International Astronomical Union) meetings are held at different venues every year. There are fewer than 20,000 astronomers in the world, therefore these conferences provide excellent opportunities to interact with other astronomers and to see what research they are working on.

Observational astronomers often have to travel to various observatories to carry out their research, as these observatories are located all over the world, from Puerto Rico, to Hawaii, Europe, Australia, Chile, or even the South Pole.

Astronomers spend a lot of their time reading publications like the Astrophysical Journal for example, either learning new subjects, or just keeping up with major developments and current research in the field of astronomy. Often, the first part of the day is spent checking out the new astronomy papers that have been uploaded on the arXiv, an open-access archive of new journal articles.

Astronomers also spend a lot of time writing papers and proposals, as writing and publishing papers is necessary in order to display and share research and results. Writing grant proposals is also necessary in order to get funding from various sources for research. Writing observing proposals needs to be done in order to get permission to use different telescopes and facilities to further research.

What are the sub-fields of Astronomy?

Astronomy is the study of everything beyond the Earth's atmosphere. It applies physics, biology and geology to explain the origin and evolution of space, stars and celestial bodies. Individuals thinking of going into this field of study may wish to focus specifically on one sub-field.

A telescope used to see into space.

The four sub-fields of Astronomy are: Astrophysics; Astrometry; Astrogeology; and Astrobiology. The following gives a brief description of each sub-field and its focus.

Astrophysics
Astrophysics, as a scientific discipline, was born in mid-nineteenth century Europe. Observational astrophysics focuses on recording data by using telescopes and other astronomical equipment to observe celestial objects. Theoretical astrophysics focuses on creating theoretical models and figuring out the observational implications and consequences of those models.

Similar to geophysics, which is the study of Earth's physics, astrophysics is the branch of astronomy that applies the laws of physics to explain the birth, life, and death of objects in the universe (such as planets, stars, galaxies and nebulae). Interacting with objects in space is done by studying the amount of radiation they emit. These emissions given off by planets, stars etc., are examined by looking at certain properties, such as temperature, density, luminosity, and chemical composition.

Much of astrophysics is focused on developing theories that will help us understand how radiation is produced. Astrophysicists apply many disciplines of physics to do this, including nuclear and particle physics, atomic and molecular physics, electromagnetism, relativity, thermodynamics, classical mechanics, statistical mechanics, and quantum mechanics.

Astrophysics is very tightly knit with both astronomy and cosmology. The differences between the three are: astrophysics creates physical theories of small to medium-size structures in the universe; astronomy calculates motions, positions, and luminosities; and cosmology creates physical theories of the largest structures in the universe and studies the expansion and evolution of the universe as a whole.

Astrometry
Astrometry is the branch of astronomy that focuses on the precise measurement of where stars and other celestial bodies are positioned and move in space. It is the oldest scientific method used to map and detect the positions and movements of extrasolar planets (an extrasolar planet is any planetary body that is outside the solar system and that usually orbits a star other than the Sun). Astrometric measurements can provide invaluable information on the movements and origin of the Solar System and the Milky Way, a frame of reference for the movement of stars and individual objects in space, and can also help to determine the distribution of dark matter in the galaxy.

Another aspect of astrometry is error correction, as there are a few factors that can introduce errors into the measurement of a star's position. These factors include: errors made by the observer, imperfections in the measuring instruments, and atmospheric conditions. Instrument improvements and making compensations to the data can reduce these errors. The results can then be studied and analyzed by using statistical processes to calculate data estimates and error ranges.

Astrogeology
Astrogeology can be viewed as the parent science of the Earth sciences. It is very much like the Earth sciences, but for other bodies in our solar system. Astrogeology (also known as planetary geology or exogeology), focuses on the geology (rocks, terrain, and material) of the planets and their moons, asteroids, comets, and meteorites. Astrogeology looks at understanding what the internal structure is of the terrestrial planets (terrestrial planets are planets that are mainly composed of rocks or metals, such as Mercury, Venus, Earth, and Mars) and looks at volcanoes, lava flows, impact craters, rift valleys, and wind activity on these planets. The structure of the giant planets and their moons as well as the make-up of the minor bodies of the Solar System are also studied.

Research in this field is ongoing, and every discovery helps scientists to better understand the Earth's evolution in comparison with that of its neighbours in the solar system. Every planet in our solar system has unique geological features which scientists have uncovered over the years through telescope observations or through data returned by space probes.

Each planet in the solar system has its own specialized study:
Heliology - the study of the Sun
Hermeology - the study of Mercury
Cytherology - the study of Venus
Selenology - the study of the Moon
Areology - the study of Mars
Zenology - the study of Jupiter
Kronology - the study of Saturn
Uranology - the study of Uranus
Poseidology - the study of Neptune
Hedeology - the study of Pluto

Astrobiology
Astrobiology (formerly known as exobiology), is the branch of astronomy that focuses on the search for life outside Earth. It is the study of the origin, evolution, distribution and future of life in the universe, and considers the question of whether extraterrestrial life exists, and if it does, how humans can detect it. NASA’s current astrobiology program addresses three fundamental questions: How does life begin and evolve? Is there life beyond Earth and, if so, how can we detect it? What is the future of life on Earth and in the universe?

While astrobiology is very much an emerging and developing field, the question of whether extraterrestrial life exists elsewhere in the universe is a justified theory and therefore a valid scientific inquiry. Planetary scientist David Grinspoon calls astrobiology "a field of natural philosophy, grounding speculation on the unknown, in known scientific theory". The field of astrobiology has made an enormous effort to underline the importance of education, both to train the next generation of scientists, and to also keep the public aware of any breakthroughs.

This field was once considered outside the mainstream of scientific inquiry, but has now become a formalized field of study. Twenty years ago, no universities had dedicated degree programs in astrobiology and very few even offered a course in this field. Today, every major university in the country has at least one course in astrobiology and many have degree programs.

Missions are just starting to take astrobiology to new levels of understanding. Astrobiology will endure long into the future given the endless fascination with questions about the origins and prevalence of life.

Astronomers are also known as:
Astronomy Professor Astrophysicist