What is Astrophysics?
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laws of physics and chemistry to explain the birth, life and death of stars, planets, galaxies, nebulae and other objects in the universe. It has two sibling sciences, astronomy and cosmology, and the lines between them blur.
NASA states that those goals produce three broad questions:
How does the universe work?
How did we get here?
Are we alone?
according NASA's website.
It began with Newton
While astronomy is one of the oldest sciences, theoretical astrophysics began with Isaac Newton. Prior to Newton, astronomers described the motions of heavenly bodies using complex mathematical models without a physical basis. Newton showed that a single theory simultaneously explains the orbits of moons and planets in space and the trajectory of a cannonball on Earth. This added to the body of evidence for the (then) startling conclusion that the heavens and Earth are subject to the same physical laws.
Perhaps what most completely separated Newton's model from previous ones is that it is predictive as well as descriptive. Based on aberrations in the orbit of Uranus, astronomers predicted the position of a new planet, which was then observed and named Neptune. Being predictive as well as descriptive is the sign of a mature science, and astrophysics is in this category.
Milestones in astrophysics
Because the only way we interact with distant objects is by observing the radiation they emit, much of astrophysics has to do with deducing theories that explain the mechanisms that produce this radiation, and provide ideas for how to extract the most information from it. The rst ideas about the nature of stars emerged in the mid-19th century from the blossoming science of spectral analysis, which means observing the specic frequencies of light that particular substances absorb and emit when heated. Spectral analysis remains essential to the triumvirate of space sciences, both guiding and testing new theories.
Early spectroscopy provided the rst evidence that stars contain substances also present on Earth. Spectroscopy revealed that some nebulae are purely gaseous, while some contain stars. This later helped cement the idea that some nebulae were not nebulae at all — they were other galaxies!
In the early 1920s, Cecilia Payne discovered, using spectroscopy, that stars are predominantly hydrogen (at least until their old age). The spectra of stars also allowed astrophysicists to determine the speed at which they move toward or away from Earth. Just like the sound a vehicle emits is different moving toward us or away from us, because of the Doppler shift, the spectra of stars will change in the same way. In the 1930s, by combining the Doppler shift and Einstein's theory of general relativity, Edwin Hubble provided solid evidence that the universe is expanding. This is also predicted by Einstein's theory, and together form the basis of the Big Bang Theory.
Career In Astrophysics
Becoming an astrophysicist requires years of observation, training and work. But you can start becoming involved in a small way even in elementary and high school, by joining astronomy clubs, attending local astronomy events, taking free online courses in astronomy and astrophysics, and keeping up with news in the eld on a website such as Space.com.
In college, students should aim to (eventually) complete a doctorate in astrophysics, and then take on a post-doctoral position in astrophysics. Astrophysicists can work for the government, university labs and, occasionally, private organizations.
Study.com further recommends the following steps to put you on the path to being an astrophysicist:
Take math and science classes all through high school. Make sure to take a wide variety of science classes. Astronomy and astrophysics often blend elements of biology, chemistry and other sciences to better understand phenomena in the universe. Also keep an eye out for any summer jobs or internships in math or science. Even volunteer work can help bolster your resume.
Pursue a math- or science-related bachelor's degree. While a bachelor in astrophysics is the ideal, there are many other paths to that eld. You can do undergraduate study in computer science, for example, which is important to help you analyze data. It's best to speak to your high school guidance counselor or local university to nd out what degree programs will help you.
Take on research opportunities. Many universities have labs in which students participate in discoveries — and sometimes even get published. Agencies such as NASA also offer internships from time to time.
Finish a doctorate in astrophysics. A Ph.D. is a long haul, but the U.S. Bureau of Labor Statistics points out that most astrophysicists do have a doctoral degree. Make sure to include courses in astronomy, computer science, mathematics, physics and statistics to have a wide base of knowledge.
Natalie Hinkel, a planetary astrophysicist who was then at Arizona State University, gave a lengthy interview with Lifehacker in 2015 that provided a glimpse into the rewards and challenges of being a junior astrophysics researcher. She described the long number of years she has put into doing her research, the frequent job switches, her work hours and what it's like to be a woman in a competitive eld. She also had an interesting insight about what she actually did day to day. Very little of her time is spent at the telescope.
"I spend the vast majority of my time programming. Most people assume that astronomers spend all of their time at telescopes, but that's only a very small fraction of the job, if at all. I do some observations, but in the past few years I've only been observing twice for a total of about two weeks," Hinkel told Lifehacker.
By Pavan B N Jamdar
Ref; NASA Web/Google
