Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
57 Cards in this Set
- Front
- Back
Equinox |
The two times of the year when daylight and nighttime are equal length |
|
Summer solstice |
Marks the longest daylight of the year |
|
Winter solstice |
Marks the shortest daylight of the year |
|
Heliocentric |
The sun was the centre of the universe ( copernicus) |
|
Geocentric |
Earth was the centre of the universe ( Aristotle) |
|
Orbit types |
- Spiral shaped- Elliptical- Irregular |
|
Nebula |
An accumulation of gas and dust |
|
Black hole |
A super-dense remnant of a supernova; an object around which gravity is so intense that even light cannot escape (death of a supergiant ) |
|
Star/Sun |
Hot, glowing ball of gas (mainly hydrogen but also helium) |
|
Solar wind |
Accidental of electrically charged particles discharge by the sun in every direction |
|
Solar flare |
A sudden flash of increased Sun's brightness |
|
CME(Coronal Mass Ejection) |
A significant release of plasma and magnetic field from the solar corona |
|
Earth's magnetic field |
- Protects Earth from harmful space radiation - A magnetic field extruding from the Earth’s poles that surrounds the planet |
|
Aurora borealis |
Caused by electrons from the sun colliding with earth's atmosphere |
|
Asteroids |
Small, rocky bodies orbiting the Sun and lying mainly in a narrow belt between Mars and Jupiter |
|
Meteoroid |
Pieces of rock floating through space (larger than an asteroid) |
|
Meteor |
meteoroids that get pulled into the atmosphere…they glow brightly because of the heat of friction |
|
Meteorite |
meteors that have hit the Earth’s surface |
|
Comet |
A celestial body composed of dust and ice that orbits the Sun |
|
Telescope |
Reflect and refract light to enhance the ability to view the sky/space |
|
Sextant |
Measure the angle between an astronomical object and the horizon for the purposes of celestial navigation. |
|
Cross staff |
Used to measure the angle between the moon and any given star Arabians |
|
Quadrant |
- Measure the altitude of celestial objects above the horizon - Egyptian |
|
Astrolabe |
Used to make accurate charts of star positions Arabians |
|
Constellations |
A group of stars that form patterns in the night sky |
|
Asterisms |
- Any pattern of stars recognized in the night sky- May be part of more than one constellation |
|
Star birth |
1. gas and dust nebulae starts collapsing -> smaller rotating cloud 2. Turns into a protostar by the mass at the core and temperature increases to get really hot. 3. Once the core reaches 10 000 000°C, hydrogen -> helium, releases great quantities of energy and radiation forming a star. |
|
Star circle of life |
- Nebula - Sun-like stars or massive stars - Red giant; red supergiant - White dwarf; supernova - Black dwarf; neutron star or black hole |
|
Parsec |
- Used to measure large distances to astronomical objects outside the Solar System- Equal to 30 trillion kilometers or 3.26 light years |
|
Kilometer |
- Used officially for expressing distances between geographical places on land in most of the world- Equal to 1000 metres |
|
Light year |
- Used to express astronomical distances - Represent the distance that light travels in a year |
|
Astronomical Unit |
- Equals to 149 599 000 km- Distance from the centre of the earth to the centre of the sun |
|
Altitude |
How high up in the sky |
|
Azimuth |
Compass direction in degrees from North |
|
Zenith |
An altitude of 90° |
|
Celestial sphere |
An abstract sphere, with an arbitrarily large radius, that is concentric to Earth |
|
Planets from closest to farthest |
1. Mercury2. Venus3. Earth4. Mars5. Jupiter6. Saturn7. Uranus8. Neptune |
|
Terrestrial planets planets |
The inner planets are smaller and rockier(Mercury,Venus, Earth, Mars) |
|
Jovian planets |
The outer planets are large and gaseous(Jupiter, Saturn, Uranus, Neptune) |
|
Aristotle |
Thought that earth was at the centre of the universe |
|
Copernicus |
Thought that the sun was at the centre of the universe |
|
Galileo |
Used the telescope to prove that the earth wasn't at the centre of the universe |
|
Kepler |
Planets orbit in a ellipse |
|
Largest planet |
Jupiter |
|
Longest day |
Venus |
|
Longest year |
Neptune |
|
Shortest day |
Jupiter |
|
Shortest year |
Mercury |
|
Most rings |
Saturn |
|
Hurricane eye |
Jupiter |
|
What is a nebula composer of |
- 75% hydrogen - 23% helium - 2% oxygen - nitrogen - carbon - silicate dust |
|
Protostar |
- a contracting mass of gas in the first stage of stars formation - materials form the nebula are drawn together - mass of the core increases - temperature climbs |
|
Who was the Hertzsprung Russell diagram founded by |
Ejnar Hertzsrung and Henry Norris Russell |
|
What is the Hertzsprung Russell diagram |
Compares the surface temperature of stars with the stars brightness |
|
What does the Hertzsprung Russell diagram measure verically |
- The brightness of a star - increasing brightness - bright ^ | Dim
|
|
What does the Hertzsprung Russel diagram measure horizontally |
- Measures the temperature of a star - decreasing temprature Hot---> cool |
|
Protoplanet hypothesis |
- a model explaining the birth of a star 1. a cloud of gas and dust in space begins swirling. 2. most of the material (more than 90%) accumulates in the centre, forming the Sun. 3.the remaining material accumulates in smaller clumps circling the centre. These form the planets. |