Science facts for kids
Science is what we do to find out about the natural world. Natural sciences include physics, chemistry, biology, geology and astronomy. Science uses mathematics and logic, which are sometimes called "formal sciences". Natural science makes observations and experiments. Science produces accurate facts, scientific laws and theories. 'Science' also refers to the large amount of knowledge that has been found using this process.
Research uses the scientific method. Scientific research uses hypotheses based on ideas or earlier knowledge, which can be categorized through different topics. Then those hypotheses are tested by experiments.
People who study and research science and try to find out everything about it are called scientists. Scientists study things by looking at them very carefully, by measuring them, and by doing experiments and tests. Scientists try to explain why things act the way they do, and predict what will happen.
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Scientific method
Today, "science" usually refers to a way of pursuing knowledge, not just the knowledge itself. It is mainly about the phenomena of the material world. In the 17th and 18th centuries scientists increasingly sought to formulate knowledge in terms of laws of nature such as Newton's laws of motion. And over the course of the 19th century, the word "science" became increasingly associated with the scientific method itself, as a way to study the natural world, including physics, chemistry, geology and biology.
It was in the 19th century also that the term scientist was created by William Whewell. He meant it to distinguish those who sought knowledge on nature from those who sought other types of knowledge.
The scientific method is the name given to the methods used by scientists to find knowledge. The main features of the scientific method are:
- Scientists identify a question or a problem about nature. Some problems are simple, such as "how many legs do flies have?" and some are very deep, such as "why do objects fall to the ground?"
- Next, scientists investigate the problem. They work at it, collecting facts. Sometimes all it takes is to look carefully.
- Some questions cannot be answered directly. Then scientists suggest ideas, and test them out. They do experiments and collect data.
- Eventually, they figure out what they think is a good answer to the problem. Then they tell people about it.
- Later, other scientists may agree or not agree. They may suggest another answer. They may do more experiments. Anything in science might be revised if we find out the previous solution was not good enough.
An example
A famous example of science in action was the expedition led by Arthur Eddington to Principe Island in Africa in 1919.
He went there to record the positions of stars around the Sun during a solar eclipse. The observation of star positions showed that the apparent star positions close to the Sun were changed. In effect, the light passing the Sun was pulled towards the Sun by gravitation. This confirmed predictions of gravitational lensing made by Albert Einstein in the general theory of relativity, published in 1915.
Eddington's observations were considered to be the first solid evidence in favour of Einstein's theory. Had the observations resulted differently, this would have counted against Einstein's theory, and perhaps refuted it (shown it was wrong).
Practical impacts of scientific research
Discoveries in fundamental science can be world-changing. For example:
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Research Impact Static electricity and magnetism (1600)
Electric current (18th century)All electric appliances, dynamo's, electric power stations, modern electronics, including electric lighting, television, electric heating, magnetic tape, loudspeaker, plus the compass and lightning rod. Diffraction (1665) Optics, hence fiber optic cable (1840s), cable TV and internet Germ theory (1700) Hygiene, leading to decreased transmission of infectious diseases; antibodies, leading to techniques for disease diagnosis and targeted anticancer therapies. Vaccination (1798) Leading to the elimination of most infectious diseases from developed countries and the worldwide eradication of smallpox. Photovoltaics (1839) Solar cells (1883), hence solar power, solar powered watches, calculators and other devices. The strange orbit of Mercury (1859) and other research
leading to special (1905) and general relativity (1916)Satellite-based technology such as GPS (1973), satnav and communications satellites. Radio waves (1887) Radio quickly became known for its use in broadcast radio (1906) and television (1927) entertainment. It was also much used in areas of telephony, emergency services, radar (navigation and weather forecasting), medicine, astronomy, wireless communications, and networking. Radio research also led to the use of microwaves, for heating and cooking food. Radioactivity (1896) and antimatter (1932) Cancer treatment (1896), Radiometric dating (1905), nuclear reactors (1942) and weapons (1945), PET scans (1961), and medical research (with isotopic labelling) X-rays (1896) Medical imaging, including computer tomography Crystallography and quantum mechanics (1900) Semiconductor devices (1906), hence modern computing and telecommunications including the integration with wireless devices: the mobile phone Plastics (1907) Starting with bakelite, many types of artificial polymers for numerous applications in industry and daily life Antibiotics (1880's, 1928) Salvarsan, Penicillin, doxycycline etc. Nuclear magnetic resonance (1930's) Nuclear magnetic resonance spectroscopy (1946), magnetic resonance imaging (1971), functional magnetic resonance imaging (1990's).
Other features of science
Not everyone completely agrees about how science works. Some philosophers and scientists say that scientific theories are only accepted for the time being. They last so long as they are the best explanation. When theories no longer explain the data, they are discarded and replaced. Or, sometimes scientists will make a theory better rather than discard it, or they will keep on using the theory hoping that it will be made better eventually.
Science is a way to get knowledge by discarding what is not true.
Scientists must be very careful to make explanations that fit well with what they observe and measure. They compete to provide better explanations. An explanation might be interesting or pleasing, but if it does not agree with what other scientists really see and measure, they will try to find a better explanation.
Before a scientific article is published, other scientists read the article and decide whether the explanations make sense from the data. This is called peer review. After articles are published, other scientists will also check if the same experiments, observations or tests produce the same data again. Peer review and repeating experiments are the only way to be sure the knowledge is correct.
Science makes models of nature, models of our universe, and medicine. There are many different sciences with their own names. However it is not right to say "science says" any one thing. Science is a process, not just the facts and rules believed at one time.
Some types of science
- Natural sciences
- Formal and applied sciences
Related pages
Images for kids
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Chronology of the universe as deduced by the prevailing Big Bang theory, a result from science and obtained knowledge
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The Plimpton 322 tablet by the Babylonians records Pythagorean triples, written in about 1800 BCE
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Plato's Academy mosaic, made between 100 BCE to 79 AD, shows many Greek philosophers and scholars
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The first page of Vienna Dioscurides depicts a peacock, made in the 6th century
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Drawing of the heliocentric model as proposed by the Copernicus's De revolutionibus orbium coelestium
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Title page of the 1687 first edition of Philosophiæ Naturalis Principia Mathematica by Issac Newton
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Radio light image of M87* black hole, made by the earth-spanning Event Horizon Telescope array in 2019
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A steam turbine with the case opened, such turbines produce most of the electricity used today
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Cover of the first issue of Nature, 4 November 1869
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Picture of scientists in 200th anniversary of the Prussian Academy of Sciences, 1900
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Dinosaur exhibit in the Houston Museum of Natural Science
See also
In Spanish: Ciencia para niños
