Astronomy Final - multiple choice

What is the distance between the Earth and the sun?

A. 1 AU B. 1 Lightyear C. Less than 7 D. We haven't been able to make that measurement yet

A. 1 AU

What happens when you compress a gas?

A. The pressure increases, therefore the temperature increases B. The pressure decreases, therefore the temperature increases C. The temperature increases with no effect on the overall pressure D. The pressure increases with no effect on the overall temperature

A. The pressure increases, therefore the temperature increases

Which of the following is not a stellar property depicted by the HR diagram?

A. Temperature B. Color C. Mass D. Luminosity

C. Mass

4. At What distance from a celestial object would the apparent (m) and absolute (M) magnitude be equal?

A. 1 parsec B. 10 parsecs C. 100 Parsecs D. 1 kiloparsec

B. 10 parsecs

Given the HR diagrams below, which of these star clusters is the oldest

C

What is the Chandrasekhar Limit?

A. A mass limit for a neutron star B. A mass limit for a white dwarf C. A radius limit for a neutron star D. A radius limit for a white dwarf

B. A mass limit for a white dwarf

How is the apparent magnitude of a celestial object defined?

A. The flux as measured from the surface of the sun? B. The flux as measured from 10 parsecs C. The flux as measured from the surface of an object D. The flux as measured from Earth

D. The flux as measured from Earth

Which of the following is not listed on the x-axis of an HR diagram?

A. Wavelength B. Color C. Radius D. Temperature

C. Radius

If you replaced the mass of the Sun with a black hole of equal mass, what would happen to the solar system?

A. Everything in the solar system would be sucked in B. All of the planets' orbital speeds would significantly increase C. Nothing would change about the orbits in the Solar System

C. Nothing would change about the orbits in the Solar System

What is the correct order of the stellar spectral types from highest to lower temperature

A. AGKMOBF B. OBAFGKM C. MOBFAKG C. BAGMOKF

B. OBAFGKM

In what part of the EM spectrum is the sun emitting spectral types from highest to lower temperatures?

A. Gamma B. Optical C. Ultraviolet D. Infrared

B. Optical

What does a spectrum do?

A. Splits an atom into 2 smaller atoms B. Refracts white light into the colors of the rainbow C. Causes an electron to descend 1 or more energy levels, emitting a photon in the process D. counts the number of photons at every wavelength (or frequency)

D. counts the number of photons at every wavelength (or frequency)

I am observing 2 galaxies. The first has an apparent magnitude of m=12, and the second m=17. How many times brighter is the first galaxy than the second?

A. 10 B. 50 C. 100 D. 500

C. 100

what is the distance modulus of an object at a distance of 1 kiloparsec?

A. 10 B. 100 C. 1,000 D. 10,000

A. 10

I am observing 2 identical stars. If one star is 5 times further from me, I observe that star to be ____ times dimmer than the closer star

A. 5 B. 25 C. 125 D. 625

B. 25

T/F Magnitudes are defined such that 10 steps is equivalent to 100 steps in brightness

false

T/F All fusion in the cores of stars stops at magnesium

false

T/F low mass stars can fuse and produce elements all the way up to iron (Fe) before transitioning into the red giant phase

false

T/F The sun's luminosity will rise to 1000 times its current level during evolution

true

T/F most elements present on the periodic table are produced by stars, either in cores by stellar explosions

true

T/F Each time a high-mass star turns out of a heavier element to fuse, it fuses heavier elements more rapidly in the core due to a large increase in temperature.

false

T/F A star's radius has the greatest effect on its luminosity

false

T/F A nearby star's spectrum reveals that its peak wavelength is 1000 nm, placing most of its emitted photons in the infrared. Therefore, I can conclude that this star is hotter than the sun.

false

T/F An electron will absorb a photo if it descends one or more energy level of an atom

false

T/F It is extremely rare to find a white dwarf in a binary star system

false

What is not a reason why main sequence fitting works

A. All stars in a cluster are the same age at the same distance B. Every MS has roughly the same inherent shape, the differences are the number of stars and where they appear on the MS C. All main sequences of every star cluster are the same D. Any difference in apparent magnitude between two clusters is due to distance

C. All main sequences of every star cluster are the same

which of the following cannot be listed on the x-axis of an HR diagram?

A. Age B. Color C. Radius D. Wavelength

C. Radius

Which of the following correctly lists all the galaxy types from youngest to oldest

A. Elliptical, Spiral, Lenticular B. Elliptical, Lenticular, Spiral C. Lenticular, Spiral, Elliptical D. Spiral, Lenticular, Elliptical

D. Spiral, Lenticular, Elliptical

Where are stars made in the milky way

A. In the bulge B. In the disk C. In the halo D. In the subhalo

B. In the disk

What is cosmology

A. The study of the structure and evolution of stars B. The study of the structure and evolution of the milky way C. The study of the structure and evolution of galaxies D. The study of the structure and evolution of universe

D. The study of the structure and evolution of universe

How are stars orbiting around a galaxy if they're located in a bar

A. Their orbits are similar to other stars in the galaxy, there is just an over dense region of stars in the bar B. Their orbits are highly eccentric around the bar C. Their orbits are more circular than disk or bulge stars

B. Their orbits are highly eccentric around the bar

What would the hubble classification be for the the galaxy on the right?

A. SBd B. E5 C. Sa D. SBb

D. SBb

Where are cepheids found on the HR diagram

A. Middle of the main sequence B. Instability Strip C. Red Giant Branch D. Near the top

B. Instability Strip

What features about distant galaxies do we observe that provide evidence for more frequent interactions in the early universe?

A. There were more prominent bulges in spirals compared to today B. There were higher numbers of ellipticals in the early universe C. There were more prominent disks in spirals compared to today D. Distant galaxies appear to have disturbed morphologies

D. Distant galaxies appear to have disturbed morphologies

Molecular clouds, planetary nebulae, and supernovae all exhibit this type of spectrum

A. Absorption 2. Emission C. Continuous

2. Emission

where will the milky way's gas be in 1 trillion years

A. Blown out of the galaxy B. Still recycling like it is now C. locked in white dwarfs and low mass stars

C. locked in white dwarfs and low mass stars

If a protogalactic cloud has little to (approximately) no angular momentum, what will it likely turn into?

A. A spiral B. An elliptical C. A massive star D. A black hole

B. An elliptical

In which part of the EM spectrum would starburst galaxies shine the brightest?

A. Radio B. Infrared C. Ultraviolet D. X-ray

B. Infrared

The furthest distances that Leavitt's Law can reach are

A. other universes B. Other star clusters in the milky way C. other stars in the milky way D. other galaxies

D. other galaxies

why does ongoing star formation in spiral galaxies lead to a blue appearance?

A. There aren't any yellow or red stars in spirals B. Short-lived blue stars outshine the other stars C. Gas in the disk preferentially scatters blue light

B. Short-lived blue stars outshine the other stars

T/F Spiral arms cannot be produced by gravitational interaction with another galaxy

false

T/F Irregular galaxies have no defined shape and usually no central bulge, but they can have ongoing star formation

True

T/F Tip of the red giant branch stars all share the same absolute magnitude in the V filter

False

T/F Stars in the disk of the milky way are typically younger than halo or bulge stars

true

T/F Lenticulars usually don't have spiral arms but they do have disks, which means lenticulars also have ongoing star formation

false

T/F Leavitt's Law cannot be used for distances outside of the milky way

false

T/F Spiral galaxies are much more commonly found in clusters

false

T/F protogalactic clouds that had leftover angular momentum are believed to have evolved into disk galaxies

true

T/F the faber-Jackson relation be applied to both elliptical and spiral galaxies

false

T/F the diameter of the milky way is roughly 30 kpc

true

Which of the following is not one of the conclusions of Hubble's Law?

A. The farther a galaxy's distance, the larger the redshift B. The universe is expanding C. The velocities of the Local Group show infall into the Virgo Cluster D. Further galaxies have larger recessional velocities

C. The velocities of the Local Group show infall into the Virgo Cluster

2. If I assume He 70 km/s/Mpc, and 1 measure a galaxy's recessional velocity to be 3500 km/s, what is the distance to this galaxy in Mpt according to Hubble's Law?

A. 25 Mpc B. 50 MpC C. 75 MpC D. 100 MpC

B. 50 MpC

During what era of the early Universe were photons finally released?

A. Particle Era B. Nucleosynthesis Era C. Atoms Era D. Galaxies Era

C. Atoms Era

Which of the following galaxy characteristics has not been observed to correlate with supermassive black hole mass?

A. Bulge Mass B. Bulge luminosity C. Galaxy Stellar Mass D. Cryonic Mass E. None of the above

E. None of the above

Which rung of the distance ladder did Hubble use to prove Andromeda was its own galaxy separate from the Milky Way?

A. Type la supernovae B. The Tully Fisher Relation C.TRGB Stars D. Leavitt's Law

D. Leavitt's Law

Which of the following is not one of the 4 fundamental forces of the Universe?

A. Strong Force B. Hydrostatic Force C. Weak Force D. Gravity

B. Hydrostatic Force

Dark matter comprises approximately % of the Universe

A. 25% B. 50% C.75% D. 100 %

A. 25%

In which type of galaxy are type la supernovae most likely to occur?

A. Spirals B. Ellipticals C. Lenticulars d. Both a and b

d. Both a and b

What is the observable Universe?

A. All photons which have had time to travel to us. B. The portion of the sky unobscured by the disk of the Milky Way All C. photons in the Universe which we have detected so far. D. A term for all bodies in the Universe which emit photons.

A. All photons which have had time to travel to us.

Which of the following is a possible conclusion from the disagreement between the values of Ho?

a. Something is possibly wrong with our models of the Universe B. There is possibly new physics to understand about the inverse C. Something is possibly wrong with our methods of observation. d. All of the above E. None of the above

d. All of the above

Consider the AGN Unified Model below, Match and fill in the designated components to the corresponding numbers

11. Seyfert 1

12. Seyfert 2

13. Broad Line Region

14. Narrow Line region

15. Torus

T/F The supermassive black hole at the center of Messier 87 is larger than our Solar System

True

T/F A Type IA supernova is the explosion of the outer layers of a massive star after the core collapses

False

T/F On large scales, the distribution of matter in the Universe is even without a center or edge.

True

T/F We have directly imaged both Sagittarius A and the supermassive black hole at the center of Messier 87 with the Event Horizon Telescope

True

T/F Hubble Flow gets weaker for galaxies at further distances while gravitational interactions get stronger

False

T/F As you move backwards in the Universe's timeline, the strength of gravity increases.

True

T/F The present day Universe has a closed geometry

False

T/F Supernova explosions can shine as bright as an entire galaxy for weeks to months

True

T/F From every galaxy's perspective, nearly every galaxy in the Universe is moving away from them

True