Advertisement.

EnchantedLearning.com is a user-supported site.
As a bonus, site members have access to a banner-ad-free version of the site, with print-friendly pages.
Click here to learn more.

ad
(Already a member? Click here.)


You might also like:
Zoom Astronomy Glossary: TZoom Astronomy Glossary: HAtomic WeightProtonChemical Elements Wheel - Common Metals: Printable WorksheetToday's featured page: Knock-Knock Jokes and Riddles for Kids


Table of Contents Enchanted Learning
All About Astronomy
Site Index
Our Solar System Stars Glossary Printables, Worksheets, and Activities
The Sun The Planets The Moon Asteroids Kuiper Belt Comets Meteors Astronomers

Astronomy Dictionary
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Click on an underlined word for more information on that subject.

F



FACE ON MARS

This photograph of the Cydonia Mense region of Mars was taken by NASA's Mars Global Surveyor in 1998. It is a coincidental alignment of rocks and other geologic formations that happens to look like a human face from this angle.


FACULAE

Falculae are bright patches on the sun that are associated with sun spots or any region which is brighter than the surrounding area on a planet or a moon.


FALLING STAR

A falling star is not a star at all; it is a meteor (made of rock and/or iron) which is burning up in the Earth's atmosphere.


FAMILY OF CONSTELLATIONS

There are many families of constellations, constellations that are either close to one another or have some other relationship. Some constellation families include the Zodiac (the 12 constellations representing the signs of the Zodiac), the Ursa Major Family (10 constellations, including Ursa Major, Ursa Minor Canes Venatici, Bootes, Coma Berenice, Corona Borealis, etc.), the Perseus Family (9 constellations, including Cassiopeia, Cepheus, Andromeda, Perseus, etc.), the Hercules Family (19 constellations, including Hercules, Sagitta, Aquila, etc.), the Orion Family (5 constellations, including Orion, Canis Major, Canis Minor, Monoceros, and Lepus), the Heavenly Waters (9 constellations, including Delphinus, Columba, Equuleus, Vela, Puppis, etc.), the Bayer Group (11 constellations, including Hydrus, Dorado, Volans, Apus,etc.), the La Caille Family (13 constellations, including Norma, Fornax, Circinus, etc.).


FINDERSCOPE or FINDER

A finderscope (or finder) is a low-power telescope attached to (and aligned with) a higher-power telescope. The finder is used to locate objects in the sky easily; the higher-power telescope is then used for closer examination.


FIREBALL

A fireball is any meteor that is brighter than Venus (magnitude -4). A sonic boom often follows a fireball and they can cast a shadow. They are caused by millimeter-sized (or bigger) meteoroids disintegrating in the atmosphere.


FIREWORKS

Fireworks, the forerunners of rockets, were invented by the Chinese. The ancient Chinese invented gunpowder (made of saltpeter, sulfur, and charcoal dust) roughly 2,000 years ago, and used it for making fireworks, which were used to celebrate important occasions. Chinese fireworks were probably brought to Europe in the 1400's by European Crusaders.
First Animal and First Dog in Space
Laika (meaning "barker" in Russian) was the first dog launched into Earth orbit (other dogs were launched earlier on sub-obital flights). She was part Siberian husky and was launched in Sputnik 2 on November 3, 1957. Laika survived in Earth orbit for four days. She died in space when the batteries to the cabin over-heated. Sputnik 2 fell back to Earth on April 14, 1958, burning up during re-entry.


FIRST LIGHT

First light is a term that refers to the earliest light emitted when the first galaxies were born. The first light occured long after the Big Bang happened. The Big Bang occured roughly 15 billion years ago, but the Universe was dark until the first light came millions of years after the Big Bang, after the smooth distribution of matter following the Big Bang coalesced into clumps, eventually forming galaxies.
FIRST MONKEY IN SPACE
The first monkey in sub-orbital space was a squirrel monkey called Gordo. Gordo was launched into space on December 13, 1958, in the nose cone of the US Army rocket Jupiter AM-13. Gordo did well in the flight, but drowned in the Atlantic Ocean when the flotation device on the nose cone failed and it sank.

The next two monkeys in space, Able and Baker, were launched on May 28, 1959 (Jupiter AM-18). They were successfully retrieved after a 300 mile sub-orbital flight.

FISSION
Nuclear fission is a reaction in which an atom's nucleus is broken apart, releasing a tremendous amount of energy. Nuclear fission is used in many power plants on Earth (and is used in atomic weapons). Nuclear fission is not an important reaction in the Sun (for nuclear fusion, the nuclear reaction that occurs in the Sun, click here).
FIZEAU, HIPPOLYTE
Armand Hippolyte Louis Fizeau (1819-1896) was a French physicist who was the first person to measure the speed of light on the Earth's surface. He measured the speed of light in 1849 using a device that consisted of a light, a toothed wheel and a distant mirror. He calculated light's speed by adjusting the speed of the wheel (the distance between wheel and mirror was 5 mi/8 km) so that the time it took the wheel to move the width of one tooth was equal to the time it took the light to travel from the wheel to the mirror and back again. He also measured the speed of light in other media, and found that light travels faster in air than in water. Fizeau also realized that the motion of a star affects its spectrum. He also did early work in daguerreotype photography.
FLAMSTEED NUMBER
In each constellation, every star is given a Flamsteed number accordng to the system devided by John Flamsteed in early eighteenth century. In this scheme, the westernmost star in each constellation is given the number "1", the next star to the east is given the number 2, then 3, etc. The north-south position of a star in ignored.


FOCAL LENGTH

Focal length is the distance from the lens (or mirror) in a telescope to the point at which the object being observed is focused.


FOCUS

A focus (pleural foci) is a central point at which rays of light, heat or any other type of radiation meet after being reflected or refracted.


FOCUSER

The focuser is a knob on a telescope that brings the image into focus. It works by moving the eyepiece in and out a slight amount.


FOLD MOUNTAINS

Fold mountains are a type of mountain range that is formed when two continental plates collide (or one continental plate colliding with an oceanic plate). The colliding crust is compressed and pushed upwards (uplifted), forming mountains. For example, the Himalayas were slowly formed when the Indian plate collided with the Asia-European plate millions of years ago.


FOSSA

Fossa are long, narrow, shallow depressions on the surface of a planet.


FOUCAULT PENDULUM

A Foucault pendulum is a simple pendulum (a weight on a long string attached to a support) that tracks the rotation of the Earth. As the pendulum swings, the Earth rotates under the pendulum, so the pendulum seems to rotate. It was first demonstrated by Jean Bernard Léon Foucault, in 1851 at the Paris World's Fair.


FOUCAULT, JEAN

Jean Bernard Léon Foucault (1819-1868) was a French physicist who was the first to demonstrate how a pendulum could track the rotation of the Earth (the Foucault pendulum) in 1851. He also invented the gyroscope (1852), showed that light travels more slowly in water than in air (1850), and improved the mirrors of reflecting telescopes (1858).


FRAUNHOFER, JOSEPH

Joseph Fraunhofer (1787-1826) was a German physicist who first studied the Sun's spectra. In the early 1800s, he observed that the continuous spectrum was marred by over 700 dark lines (now called Fraunhofer lines). Fraunhofer's work with the spectra and also with diffraction gratings was seminal in the science of spectroscopy. At the time, it was unknown what caused these lines (they are caused by elements in the Sun's atmosphere absorbing light at their characteristic wavelengths).


FREE FALL

Free fall is a state that occurs while in orbit around a planet. In free fall, things appear to weightless. During free fall, the orbiting object falls toward the planet the exact same amount as the planet's surface curves beneath the object; the object seems to be continually falling toward the planet but never reaches it.


FULL MOON

A full moon appears as an entire circle in the sky; it is illuminated by the Sun and from the Earth, we see its entire daytime side. A full moon occurs once each lunar month, when the Moon is on the opposite side of the Earth from the Sun.


FUSION

Nuclear fusion is an atomic reaction in which many nuclei (the centers of atoms) combine together to make a larger one (which is a different element). The result of this process is the release of a lot of energy (the resultant nucleus is smaller in mass than the sum of the ones that made it; the difference in mass is converted into energy by the equation E=mc2). Suns are powered by nuclear fusion, mostly converting hydrogen into helium. In this process, 4 hydrogen nuclei combine to form a single helium nucleus; about 0.3% of the original mass is converted into energy
Astronomy Dictionary
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Click on an underlined word for more information on that subject.
If the astronomy term you are looking for is not in the dictionary, please e-mail us.

Enchanted Learning®
Over 35,000 Web Pages
Sample Pages for Prospective Subscribers, or click below

Overview of Site
What's New
Enchanted Learning Home
Monthly Activity Calendar
Books to Print
Site Index

K-3
Crafts
K-3 Themes
Little Explorers
Picture dictionary
PreK/K Activities
Rebus Rhymes
Stories
Writing
Cloze Activities
Essay Topics
Newspaper
Writing Activities
Parts of Speech

Fiction
The Test of Time
iPhone app
TapQuiz Maps - free iPhone Geography Game

Biology
Animal Printouts
Biology Label Printouts
Biomes
Birds
Butterflies
Dinosaurs
Food Chain
Human Anatomy
Mammals
Plants
Rainforests
Sharks
Whales
Physical Sciences: K-12
Astronomy
The Earth
Geology
Hurricanes
Landforms
Oceans
Tsunami
Volcano
Languages
Dutch
French
German
Italian
Japanese (Romaji)
Portuguese
Spanish
Swedish
Geography/History
Explorers
Flags
Geography
Inventors
US History

Other Topics
Art and Artists
Calendars
College Finder
Crafts
Graphic Organizers
Label Me! Printouts
Math
Music
Word Wheels

Click to read our Privacy Policy

E-mail


Enchanted Learning Search

Search the Enchanted Learning website for:



Advertisement.



Advertisement.



Advertisement.


Copyright ©1999-2016 EnchantedLearning.com ------ How to cite a web page