Identify the terms herein defined or the things referred to.
1. The color of the oldest stars 2. The extension of Earth's equator onto the celestial sphere 3. The brightness of a star as it appears when viewed from Earth 4. The point on the celestial sphere directly above an observer 5. The process of obtaining spectra from astronomical objects like the stars 6. The apparent annual path of the sun against the backdrop of the celestial sphere 7. A group of stars on the H-R diagram containing the majority of stars 8. The process in which two or more smaller nuclei join together and make one larger nucleus 9. A unit of distance defined as the distance of an object with a parallax angle of 1 arcsecond 10. The apparent change in the position of a nearby star against the background of more distant stors, as observed from different positions in Earth's orbit
As stars age, they run out of hydrogen to burn, decreasing the amount of energy they emit. Thus, younger stars can appear bluer while older ones appear more red, and in this way, a star's color can tell us something about that star's age.
Celestial Equator-The extension of the Earth's rotation axis to the sky defines the North and South Celestial Poles (the NCP and SCP), while the extension of the Earth's equatorial plane defines the celestial equator.
Star Brightness-Astronomers define star brightness in terms of apparent magnitude — how bright the star appears from Earth — and absolute magnitude — how bright the star appears at a standard distance of 32.6 light-years, or 10 parsecs.
Zenith-Zenith, point on the celestial sphere directly above an observer on the Earth. The point 180° opposite the zenith, directly underfoot, is the nadir.
Astronomical Spectroscopy-Astronomical spectroscopy is the study of astronomy using the techniques of spectroscopy to measure the spectrum of electromagnetic radiation, including visible light and radio, which radiates from stars and other celestial objects.
Ecliptic-ecliptic
The path the Sun appears to take around the celestial sphere each year is called the ecliptic (Figure 4). Because of its motion on the ecliptic, the Sun rises about 4 minutes later each day with respect to the stars.
White Dwarfs-The White Dwarfs are very hot stars, which are small in size and relatively dim. They are found in the lower left of the H-R Diagram.
Nuclear Fusion-Nuclear fusion is the process by which two or more atomic nuclei join together to form a single heavier nucleus and large amounts of energy.
Parallax Second-Parallax Second = Parsec (pc)
Fundamental unit of distance in Astronomy. "A star with a parallax of 1 arcsecond has a distance of 1 Parsec."
Stellar Parallax-As the Earth orbits the Sun, a nearby star will appear to move against the more distant background stars. Astronomers can measure a star's position once, and then again 6 months later and calculate the apparent change in position. The star's apparent motion is called stellar parallax.
