HW Ch 13 -- Ch 21,22
Which of the following stages will the Sun definitely go through as it gets older?
All options provided here
HH objects are luminous knots of gas in an area of star formation that are set to glow by jets of material from a protostar
Herbig-Haro
When a star settles down to a stable existence as a main-sequence star, what characteristic determines where on the main sequence in an H-R diagram the star will fall?
Its mass
Which of the following types of stars will spend the longest time (the greatest number of years) on the main sequence?
K
How are globular clusters distributed in our Milky Way Galaxy?
Mostly in a large spherical halo (or cloud) surrounding the flat disk of the Galaxy
As a cluster of stars begins to age, which type of star will move off the main sequence of the H-R diagram first?
NOT The lowest mass stars, which have the least amount of fuel for fusion NOT M-type stars, which are the coolest
Biologists tell us that life on Earth took billions of years to evolve into astronomy students and other examples of intelligent life. If we want to search for planets with intelligent life-forms that evolved over the same period of time that we did, what sorts of stars should we NOT bother searching around?
O and B type stars
Many names used by astronomers are misleading or outdated. A good example is the term planetary nebula, which astronomers use to refer to:
The shell let go by a dying low-mass star
When the core of a star reaches a temperature of about 100 million degrees (K), something new happens in the core. What is this new event?
Three Helium nuclei begin fusing Carbon (element number 6)
When the outer layers of a star like the Sun expand and it becomes a giant, which way does it more on the H-R diagram?
Toward the upper right
Astronomers identify the "birth" of a real star (as opposed to activities of protostars) with what activity in the star?
When nuclear fusion reactions began inside its core
open cluster
a comparatively loose cluster of stars, containing from a few dozen to a few thousand members, located in the spiral arms or disk of our Galaxy; sometimes referred to as a galactic cluster
association
a loose group of young stars whos spectral types, motions..
super-Earth
a planet larger than Earth, generally between 1.4 and 2.8 times the size of our planet
mini-Neptune
a planet that is intermediate between the largest terrestrial planet in our solar system (Earth) and the smallest jovian planet (Neptune); generally, mini-Neptunes have sizes between 2.8 and 4 times Earth's size
An exoplanet is a planet orbiting __________.
a star other than our Sun
The Helium Flash is a nearly explosive ignition of ________ in the triple-alpha process in the dense core of a red giant star
helium
If you want to find stars that are just being born, where are the best places to search?
in giant molecular clouds
The main-sequence turnoff location in the H-R diagram is where stars begin to ______ the main sequence
leave
______________ are large, cold interstellar clouds with diameters of dozens of light-years and typical masses of 105 solar masses; found in the spiral arms of galaxies, these clouds are where stars form.
molecular clouds
Nucleosynthesis is the building up of heavy elements from lighter ones by ___________
nuclear fusion
globular cluster
one of about 150 large, spherical star clusters (each with hundreds of thousands of stars) that form a system of clusters in the center of our Galaxy
The big surprise about the first planet discovered around another (living) star was that it
orbited so close to its star it took only 4 days to go around
A very young star still in the process of formation, before nuclear fusion begins
protostar
When one astronomical object moves in front of another
transit
