ASTRO 001 Study Guide - Midterm Guide: Type Ii Supernova, White Dwarf, Reaction Rate

134 views8 pages

tanantelope806

9 Feb 2016

School

PSU

Department

Astronomy and Astrophysics

Course

ASTRO 001

Professor

Charlton Jane

For unlimited access to Study Guides, a Grade+ subscription is required.

Document Summary

Astro 001 unit 3 sample test questions: * a large luminosity star. An estimate of the number of communicating/technological civilizations that we expect in our galaxy would have a larger number if: the average lifetime of a communicating civilization was. If the sun had twice its mass, then which of the planets would be. 12. in its habitable zone: mercury, venus, earth, neptune, jupiter. In the transit method of finding extrasolar planets, the distance. *if two stars are the same temperature, how can one be more. If they were all formed at the same time, which of the stars in the. 18. diagram above will live the longest: a, b, c, d, e, the parallax angle of a nearby star is measured to be 0. 02 arcseconds. What is the distance to the star: 20 parsecs, 2 light years, 50 parsecs, 0. 2 light years, 200 light years.

Related Questions

1. The Jeans instability occurs when
Athe pressure in a gascloud is less than its gravitationalforce.
Bthe pressure in a gascloud is greater than its gravitationalforce.
Cthe temperature in acollapsing cloud is hot enough to fuseHydrogen.
Dthe temperature in acollapsing cloud is hot enough to fuse Helium.

2. At what stage in its life does a star pass through theprotostarphase?
AAfter condensationbut before nuclear reactions begin in itscore.
BWhile it is convertinghydrogen into helium in its core.
CAfter nuclear reactionsend in its core, but before the red giantphase.
DWhen it is expanding insize as a red giant or supergiant.

3. The characteristics of an open cluster of stars are
Aa few hundredmembers, often very young and still embedded in thegas and dustfrom which they were formed.
Bmany thousand members, ofdifferent ages.
Ca few dozen members, theremnant of a globular cluster of starsfrom which most of themembers have escaped.
Dhundreds of thousands ofmembers, all very old, and no or verylittle interstellar gas anddust.

4. What is a protostar?
AA star near the endof its life, before it explodes as asupernova.
BA sphere of gas aftercollapse from an interstellar cloud butbefore nuclear reactionshave begun.
CA small interstellarcloud, before it collapses to become astar.
DA shell of gas left behindfrom the explosion of a star as asupernova.

5. What is an H II region?
AA region of hot,ionized hydrogen around one or more O and Bstars.
BA region of molecularhydrogen inside a giant molecularcloud.
CA region of neutral,atomic hydrogen in interstellar space.
DA region of gas and dustformed by the explosion of a massive star.

6. The total time that the Sun will spend as a main sequencestaris
Aabout 4.5 millionyears.
Bat least 200 billion yearsyears.
Cabout 1 millionyears.
Dabout 10 billionyears.

7. How is a star's lifetime related to its mass?
AThe lifetimes ofstars are too long to measure, so it is not knownhow (or if) theirlifetimes depend on mass.
BA star's lifetime does notdepend on its mass.
CLower-mass stars runthrough their lives faster and have shorterlifetimes.
DHigher-mass stars runthrough their lives faster and have shorterlifetimes.

8. In the Hertzsprung-Russell diagram, how does the position ofatypical star change while it is at the main sequence phase ofitsevolution?
AA star's position onthe main sequence is determined only by itsmass and not its age,and so, stars do not move along the mainsequence duringevolution.
BMassive stars (4 solarmasses) move toward the upper left as theirluminosity increases,while lower-mass stars move toward the lowerright as theirtemperature decreases.
CStars move from upperright to lower left while they are on themain sequence.
DStars move from upper leftto lower right while they are on themain sequence.

9. Why does the core of the Sun contain more helium andlesshydrogen than does the surface of the Sun?
AHelium condenses moreeasily so, when the Sun was forming the corebecame helium-rich;vast quantities of hydrogen were added onlyafter the core becamemassive enough.
BThe hydrogen has beenlifted out of the core by the Sun's magneticfield.
CHelium is heavier thanhydrogen, and has sunk toward the center ina process of chemicaldifferentiation.
DThermonuclear reactionshave converted much of the originalhydrogen in the core intohelium.

10. In terms of nuclear reactions, what is the next stage ofastar's life after the end of hydrogen burning in thecore?
AHydrogen burning ina thin shell around the core.
BHelium burning in thecore.
CCarbon burning.
DDeath (it becomes eithera supernova or a white dwarf).

ASTRO 001 Study Guide - Midterm Guide: Type Ii Supernova, White Dwarf, Reaction Rate

Document Summary

Get access

Related Documents

ASTRO 001 Lecture Notes - Lecture 3: Event Horizon, Tarantula Nebula, Orion Nebula

ASTRO 001 Study Guide - Midterm Guide: Star System, Red Supergiant Star, Stellar Magnetic Field

ASTRO 001 Lecture Notes - Lecture 4: Distant Star, Event Horizon, Photosphere

Related Questions