Intro to AST FSU
About this set
Created by:
ramshackleknight on April 23, 2012
Subjects:
Description:
For anyone who'll be in the intro to ast class at florida state.
Log in to favorite or report as inappropriate.
Order by
87 terms
Terms | Definitions |
|---|---|
 What bright planet has the Prof. mentioned on several occasions that is visible near Zenith in the evening this term? (Spring, 2012) | Jupiter |
| What object never seems to move in the night sky from dusk to dawn. | Polaris |
| If we were looking for a star with a right ascension of 12 hours and a declination of MINUS 90 degrees (i.e. -90deg), where would we find it in the sky? | Directly above the south pole. |
| A constellation has what requirement? | That the stars more or less all have similar right ascension and declination coordinates. |
| Aristotle thought the planetary orbits were perfect circles. Which astronomer showed this was not true? | Kepler |
| If an astronomer can determine the orbital period and orbital radius of a moon or satellite around a planet, what can they determine? | The mass of the planet |
| The Great March Comet of 1843 has a period of 700 years. What is its semimajor axis in astronomical units (AU)? (P^2=A^3) | About 79 AU P^2=A^3, SO (700)^2=A^3, and A=(700)^(2/3)=78.49 |
| In the above problem, when would Earthlings expect to see the Great March Comet again? (add last seen date+year period) | 1843+700=2543yrs |
| An amateur astronomer buys two incidental telescopes, each with a 10 diameter primary mirror, and places them 100 meters apart. What is the angular resolution in arcseconds of the combined two-telescope system if he links them together? Assume he is looking at a distant object that emits light of about 0.5 micrometers (i.e. 0.5 mum) in wavelength. (a= .25landa/D) | .00125 arcseconds .25*0.5/100 = 0.00125 (depends on distance between telescopes, not on the diameter of each separately) |
| What is one big difference between a Newtonian telescope and a Cassegrain Telescope? | The Cassegrain has a hole in the middle of the primary mirror. |
| Everybody knows that the bigger a visible light telescope mirror is, the better, but at some point a single piece of glass is just too heavy. What can astronomers do. | Both of these: Build a huge mirror out of smaller segmented mirrors like the Keck, and build smaller twin or quadruplet mirror telescopes and link them together as interferometer like the VLT. |
| We have discussed infrared telescopes on several occasions. What is (or are) the main features that influence such a telescope? | Both of these: The detector that makes the image must be kept cold if possible, and absorption of the infrared light in the atmosphere. |
| The angular distance between two radio sources in a binary star system is on average 1.0 arcseconds. What is the smallest radio telescope primary lens diameter ("dish") you can use to tell you that you are seeing two distinct radio sources? Assume the radio wavelength is about 1000 mum (micrometers, not nanometers!) in wavelength. (a=.25landa/D | D=.25landa/a=.25*1000/1=250m |
| Of all the possible ground or space telescopes, which one at present has the least resolution? | Gamma Ray (Compton Telescope) |
| What kind of telescope is very sensitive to heat? | Infrared (Spitzer Telescope) |
| What kind of telescope can have an effective diameter the size of the northern hemisphere? | Radio (VBLA |
| In both class and in the Planetarium show, a method was discussed that allows Earth based telescopes to improve their resolution. This is done with: | Adaptive Optics |
| In the planetarium show, they mentioned a method to reduce chromatic aberration in a refractive telescope. It was: | Make the focal point of the telescope very very long. |
| Emission spectra looks like: | A dark band with lines of light. |
| Absorption spectra looks like: | A band of light with dark lines. |
| Continuous spectra looks like: | A band of light with no dark lines. |
| Our solar system is the result of: | The gravitational collapse of a cloud of gas and dust that contained the remnants of previously exploded stars. |
| A current theory for the Moon's formation is that: | Computer simulations suggest it is the result of an indirect collision between two objects that were nearly the size of the earth and the Mars respectively. |
| Millions of years ago, before significant tectonic plate motion, most of the continents on Earth appeared to be essentially one continent. What was this called? | Pangaea |
| A seismological study of Planet X shows no evidence of S-waves. What can be said about the core. | Planet X must be mostly made of some kind of molten (liquid) material. |
| Which terrestrial planet has the most pronounced elliptical orbit. | Mars |
| How often can we see the far side of the moon from Earth with the naked eye? | Never |
| If the Earth had no magnetosphere, then: | We're all screwed (not the actual answer, but true) Actual answer: There would be no Northern or Southern Lights. |
| Which two planets, as seen from Earth, are never observed far from the sun? | Mercury and Venus |
| Why is asidereal day shorter than the solar day? | Due to the Earth's orbit, it takes longer for the Earth to rotate back to the same position with respect to the Sun than to the same position with respect to the stars. |
| How many times does the moon rotate on its axis every time it orbits the Earth once? | Once |
| We know the relative distances between the Earth, Sun and Moon vary since: | We observe both total and annular solar eclipses. |
| If the Earth's orbit around the sun were twice the radius it is now, how long in present Earth years would the new Earth year be? (P^3=A^2) | About 2.83 years, so P=2^(3/2)=2.83 yrs |
| A new star is born in our Galaxy with a visual magnitude of +7 | It can't be seen with the naked eye. |
| Which terrestrial planet has no measurable magnetic field? | Venus |
| Which planet or planets or moons both have predominantly CO2 atmospheres? | Venus and Mars |
| Which planet or moon has mare features? | The Moon |
| What planet has moons that rise both in the east and west? | Mars |
| Which planets have no tilt to their rotation axis? | Venus and Mercury |
| The largest volcanic feature in the solar system is | Olympus Mons on Mars |
| In a primary atmosphere, one might expect a planet to have significant levels of: | Hydrogen, Helium, methane, ammonia, water vapor. |
| In a secondary atmosphere, one might expect a planet to have significant levels of: | Water vapor, carbon dioxide, sulfur dioxide, nitrogen. |
| In a tertiary atmosphere, one might expect a planet to have significant levels of: | Oxygen gas |
| Triton is the largest moon of: | Neptune |
| Of the 4 Galilean moons, the one that is completely un-differentiated is: | Callisto |
| Shepherding satellites: | Stabilize the rings of the Jovian planets |
| The main NASA mission that is now exploring Mercury is: | the Messenger mission. |
| The term gravitational assist refers to: | The use of "flybys" of space craft near orbiting planets. |
| The summers and winters on Uranus: | Occur near the north and south poles |
| What is the distance in planetary radii for an object of similar density to be ripped apart by the host planet? | 2.4 planetary radii (the Roche limit) |
| What kind of "lakes" might exist on the moon Titan? | Liquid Methane |
| A KBO that is comparable in size to Pluto is: | Quaoar |
| What is the most important determining factor in stellar evolution? | Mass |
| The "surface" of the sun that we normally see is called the: | Photosphere |
| A pair of sunspots take about 14 days to go from one side of the sun to the other, as seen from Earth. What is the period of rotation of the sun? (multiply by 2) | 28 days |
| A pair of sunspots have what characteristics? | All of these: A north and south pole, they are cooler than the surrounding sun's surface, their magnetic polarity switches sign every 11 years |
| If a 10 kg zombie wuff were to suddenly be completely turned into energy, how much energy would it produce? (E=mc^2) (c=constant speed of light=3x10^8) | 9x10^17 joules. E=10*(3x10^8)^2 |
| What is the "ash" that results at the core of a heavy mass star (say 12 solar masses) just before it implodes at the end of its life? | Iron (the star killer! >:D) |
| What kind of "telescope" would you build to make a neutrino detector? | A gigantic container of fluid FAR UNDER the Earth's surface with some kind of PHOTODETECTORS lining the wall, all IN TOTAL DARKNESS. |
| About how old is our sun now, as it sits on the main sequence? | About 5 billion years |
| If the solar model involving the fusion of hydrogen into helium is correct, what must be the consequence? | The Sun must produce solar neutrinos at a certain rate. |
| The star Bathsalts 959A has a parallax of 0.001 arcseconds. How far away is it from Earth? (d=1/p) | d=1/.001=1000 parsecs |
| An astronomer is studying a star cluster and wants to know the radius of the stars in it. In this process, he comes across one that has a luminosity of 10,000L(solar), and a temperature twice that of our sun. What is its radius in solar radii? (R=L^(1/2)/T^2) | (10,000)^(1/2)/2^2=100/4=25 solar radii |
| Consider an isolated white dwarf that is on the HR diagram at .01 solar luminosities and 10,000 K today. Where would it be on the HR diagram in, say, 15 billion years from now? | It loses both luminosity and temperature with time. |
| Consider a star that is 0.1 solar masses in size. How long will it be on the main sequence? (Lifetime=10Billion years/M^2.5) | 10*1/(0.1)^2.5= 3162 billion years |
| In an orbiting binary star system, the period of the orbit is 10 years and the semimajor axis is 10 AU. What is the total mass of the binary star system? M=A^3/P^2 | 10^3/10^2=10 solar masses |
| Ultraviolet light from hot O and B stars within a nebular region can lead to: | Emission and reflection nebulae |
| The 21 cm radio wavelength indicates the presence of | hydrogen in interstellar clouds of gas and dust. |
| Which mass or mass range refers to the critical mass or masses of a neutron star? | 1-3 solar masses. |
| Which mass range best refers to objects that will "fail" as main sequence stars? | Less than 0.08 solar masses |
| Assume a star is too far away to use standard parallax methods to find its distance. What can be done to find the distance? | Measure the star's spectra, apparent brightness, and use the HR diagram to find the luminosity. (i.e. spectroscopic parallax) |
| Wich mass or mass range best refers to the SIZES OF STARS that can produce a white dwarf. | Between 0.25 and 12 solar masses |
| Which mass or mass range best refers to the CRITICAL MASS OF A WHITE DWARF? | 1.4 solar masses (i.e. the Chandrasekhar limit) |
| When our sun eventually leaves the mains sequence, it will FIRST become a: | red giant |
| When our Sun finally runs out of nuclear fuel, it will implode, resulting in: | a planetary nebula and a white dwarf |
| A star that has a mass greater than 12 solar masses may end in a | type II supernova |
| If a neutron star were to be able to accrete mass so that it became a bit larger than its critical mass, what might happen? | It could become a black hole. |
| An x-ray binary is: | A neutron star in orbit with a companion star. |
| Gamma ray bursts seem to come from: | all directions in distant galaxies. |
| Imagine the remaining material (about 10 solar masses) of a massive star forms a black hole as it collapses. What is the radius of its event horizon (Schwarzchild radius)? (Rs=3 km *M/M(solar)) | Rs=3*10/1=30 km |
| Outside, but very close to the event horizon of a black hole, if visible light is emitted away from the black hole, what might a distant observer detect due to this light? | Radio Waves |
| X-rays emitted with rapid fluctuations from a compact object with no visible light spectrum may be an indication for (of): | objects that are black hole candidates. |
| How big is a neutron star? | Approximately 20 km in diameter. |
| The "lighthouse beacon effect" refers to what kind of object? | Rotating neutron star. |
| GENERAL RELATIVITY has to do with what essential feature? | The effect of gravity on space and time. |
| What is special about globular clusters? | They are mostly made up of older stars. |
| What probability is present at the center of most galaxies? | A supermassive black hole. |
First Time Here?
Welcome to Quizlet, a fun, free place to study. Try these flashcards, find others to study, or make your own.