ASTRO-100 MAYMESTER

I refuse to fail!

Star

A large, glowing ball of gas that generates heat and light through nuclear fusion.

Planet

“Wandering object,” A moderately large object that orbits a star; It shines by reflected light. Planets may be gaseous, rocky, or icy in composition.

Moon

Any object that orbits a planet.

Asteroid

A relatively small and rocky object that orbits a star.

Comet

A small icy object that orbits a star.

Solar (or star) system

A star and all the material that orbits it, including its planets, moons, asteroids, comets, etc.

Nebula

An interstellar form of cloud or dust.

Galaxy

A great “island” of stars in space, all held together by gravity and orbiting a common center.

Universe

The total of everything that exists within a galaxy

Our Solar system

Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.

Inner Solar system: Mercury, Venus, Earth, and Mars, all surrounded by an asteroid belt.

Outer planets: Jupiter, Saturn, Uranus, and Neptune.

Astronomical Unit (AU)

The average distance between the Earth and the Sun; 93 million miles.

Light years (ly)

Distance travelled by light in one year.

Milky Way

Interior view of our galaxy

Laniakea

Cluster of galaxies, a supercluster

The Universal speed limit

Information cannot travel faster than the speed of light.

Lookback Time

The farther away Earth is from an object, the more in the past we are viewing it.

The Observable Universe

Refers to the portions of the Universe that we can see. This is the portion of the Universe that’s light we can see on Earth as of now; Information is still being sent.

The Age of the Universe

The Big Bang “created” the Universe 13.8 billion years ago.

Constellations

Specific regions of the sky with well-defined borders, centered on the Greco-Roman star patterns in the Northern Hemisphere.

Anstenums

A pattern of stars that are either not a part of an official constellation, or the pattern makes up a cluster of an actual constellation. i.e. Big Dipper and Ursa Major

Angular Size

The angle that something appears to extend across the sky.

Angular Distance

The space between the two objects is the angle separating them.

Solar Day

24 hours, the time it takes the sun to make one circuit of the sky.

Sidereal Day

23 hours and 56 minutes, the time it takes for a star to make a full circuit of the sky.

Precession

When the axis of rotation of an oblate object isn’t vertical, and this causes a slow change in the Earth’s rotational pattern.

Synchronous Rotation

The time it takes to go aaround the earth

Synodic Orbital Period

The period from new moon to new moon.

Solar Eclipse

A solar eclipse happens when, at just the right moment, the Moon passes between the Sun and Earth.

Lunar

A lunar eclipse occurs when the Sun, Earth, and Moon align so that the Moon passes into Earth's shadow.

Total lunar eclipse

Moon is really dark and red.

Partial

Only a part of the moon is lit.

Penumbral lunar eclipse

Really looks the same

The Ishango Bone

From Africa, shows ancient markings corresponding to the horns of the crescent Moon, which was used to predict the seasons.\

Mayan Astronomy

Correctly calculated the length of the year on the Mayan calander

Pythagoras of Samos

Theorized that nature can be described by Mathematics

Plato

• Developed the idea of the perfection of the Heavens and the imperfect Earth at the center of the Universe.

• Idea of the heavens: All planets had their own spheres, with the Earth at the center of the Universe.

Aristotle

• Solidified the idea of a geocentric universe, where Earth exists at the center of the universe

• Aristotle didn’t believe that the Earth was flying through space– Why?

  • Earth could not be moving because flying objects (i.e. birds, clouds) would be left behind

    • The heavens were perfect and unchanging, so orbits had to be circular

Stellar Parallax

The apparent shift in the position of a nearby star when viewed from two different places in Earth's orbit around the sun.

Aristarchus of Samos

• Proposed heliocentric theory and the absence of parallax.

• Measured the Earth’s shadow during a lunar eclipse, measured it correctly

• Calculated the distance from the earth to the moon

• Tried to predict the earth’s distance from the sun to the moon

Hipparchus of Nicaea

• Best astronomer of the ancient times; Accurately guessed the positions of over 1,000 stars

Ptolemaic Model

Predicted based on the uniform motions of planets around a stationary Earth

The multilayered shield of geocentrism

1. Claims that the Earth was the center of the Universe

2. Claims that the laws of nature were different between the Earth and the Heavens

3. The universe is not very big

   1. (Missing the last one?)