Midterm 2

Photon A has a higher energy than photon B. Given this information, which of the following statements is true for photons travelling in a vacuum?:

Photon A has a higher frequency than photon B
Photon A has a longer wavelength than photon B
Photon A has a lower frequency than photon B
Photon A has longer wavelength than photon B
Photon A travels faster than photon B

Human beings mostly emit which kind of electromagnetic radiation?:

visible
microwave
gamma rays
ultraviolet
infrared

The technique of collecting radiation and splitting it up into its components so it can be analyzed is referred to as:

photometry
spectrometry
interferometry
astrometry
colorimetry

A pattern of bright lines on a dark background is referred to as:

a bright spectrum
an emission line spectrum
a continuous spectrum
an absorption line spectrum
single spectrum

Hot dense objects like the filaments in an incandescent light bulb produce:

a continuous spectrum
no spectrum
an absorption spectrum
an emission spectrum
a mixture of absorption and continuous spectrum

Measuring the light reflected from a planet's surface and/or atmosphere allows us to determine its:

mass
distance
physical size
temperature
chemical composition

Spectral line patterns are:

unique for all astronomical objects with the same mass
the same for all elements and molecules
unique for each element and molecule
unique for each different molecule but the same for all elements
unique for each element but the same for all molecules

The main way astronomers determine the physical and chemical properties of an object in the distant universe is through:

spectroscopy
photometry
astrometry
direct measurement
photometry

Various techniques are being used to find exoplanets, and the radial velocity technique is one of them. This technique works best for:

planets in immediate galactic neighbourhood, up to 100 light years from Earth.
exoplanets whose orbits are very eccentric (very elliptical).
exoplanets which have wide orbits and very large masses.
exoplanets whose orbits are perpendicular to our line of sight (face on).
exoplanets whose orbits are nearly circular (low eccentricity).

In which of the following situations does the direct detection method of exoplanets works the best?:

exoplanets that are close to their star.
exoplanets that have already been detected by the transit method.
exoplanets whose orbits are along our line of sight (edge on).
exoplanets whose masses are equal to the mass of planet Neptune.
exoplanets that are far from their star.

In order to adjust the contraction of the solar nebula due to gravitation, the cloud:

begins to cool.
becomes more spherical in shape.
expands.
changes direction of motion.
spins faster.

Which of the following materials present in the solar system had the highest condensation temperatures?:

hydrogen compounds like water, methane, and ammonia
rocks
hydrogen and helium gases
metals
silicates and oxides

Space between any stars in our universe is filled with a huge mass of gas. The gas is composed of:

only hydrogen.
10% hydrogen, 90% helium by numbers of atoms.
ammonia, methane, and water vapour.
90% hydrogen, 9% helium by weight.
some hydrogen, but mainly carbon dioxide

As seen from Earth, our Milky Way Galaxy is not uniformly illuminated. Some regions along the plane of the Milky Way appear dark because:

stars in that region are hidden by interstellar gas.
many black holes absorb all light from those directions.
stars in that region are hidden by dark dust particles.
many brown dwarfs in those areas absorb light which they turn into heat.
there are no stars in these areas.

What effect do even thin clouds of dust have on light passing through them?:

It dims and reddens the light of all more distant stars.
Even a little can completely block all light, such as the Horsehead Nebula.
The light that passes through them is blueshifted due to the cloud's approach.
Its motion causes all light to be redshifted as it passes through these clouds.
Its motion causes the light of stars beyond to twinkle.

Asteroids and meteoroids are considered oldest objects in our solar system and in composition they are most like:

terrestrial planets.
comets.
jovian planets.
the moons of Jupiter.
Kuiper Belt objects.

Theory tells us that our solar system was formed out of a huge cloud of gas and dust. According to theory, as the huge cloud of gas and dust contracts due to gravitation, the entire mass of this cloud:

changes direction of motion.
angular momentum is the same because it spins faster
angular momentum is different because it spins slower.
becomes more spherical in shape.
begins to cool.

Which of these following statements contradicts the solar nebula theory?:

Larger planets should form closer to their star, where there is more debris.
All the planets should follow the ecliptic plane.
Planets should rotate counterclockwise as well.
The ecliptic is the equator for the Sun.
All the planets should orbit the Sun counterclockwise.

Extremely large planets orbiting very close to their parent stars are called:

Hot Jupiters
Cold Saturns
Super Earths
Super Neptunes
Brown dwarfs

Astronomers have detected most extrasolar planets by:

the "wobble" of their parent stars using spectroscopy.
observing starlight reflected by their surfaces.
direct imaging method
observing periodic dimming of starlight as a planet passes in front of the star during planetary transit.
observing the planets' changing phases as they orbit their stars.

Which of the following statements about the formation of moons in our solar system is not true?:

Most moons in our solar system probably formed together with their host planet (co-accretion).
Triton, Neptune's largest moon, is the only large moon with a retrograde orbit. It was probably captured from the Kuiper belt.
Ganymede, the largest moon of our solar system was a result of strong gravitational attraction between Jupiter and the Sun.
Our Moon probably resulted from a massive collision.
Some of the smaller moons, particularly those with irregular orbits (wrong plane and/or direction), may have been captured.

Apart from terrestrial planets, another promising place to find life in the solar system is:

beneath the surfaces of icy Jovian moons
inside comets
inside asteroids
beneath planet Mars
in the atmospheres of Jovian planets

Chunks of rock and metal that orbit the Sun but are much smaller than the planets are referred to as:

meteors
planetesimals
dwarf planets
comets
asteroids

Pluto, Eris and Ceres are all examples of:

jovian moons
Kuiper belt objects
dwarf planets
planets
asteroids

Which of the following properties of the planets in our solar system is not explained by

condensation theory?:

rotation rates
chemical compositions
direction of revolution
orbital shapes
direction of rotation

What is the definition of a star's habitable zone?:

None of these answer
The range of distances from the star where rocky planets can form
The range of distances from the star where planets with life have been detected
The range of distances from the star where liquid water can be stable on the surface of a suitable planet.
The range of distances from the star where organic molecules can be stable on the surface of a suitable planet

Which of the following is not the salient feature of a conventional habitable zone?:

Ammonia, methane, and ethane which are liquid at cold temperatures cannot be considered as liquids which can support life.
Heating by the star is the only source of heat.
Without water, any form of life is impossible.
Tidal forces are important source of heat energy in a habitable zone.
Sub-surface oceans in Europa are outside the conventional habitable zone.

Which of the following statements about the Sun's habitable zone is true as the Sun ages?:

It moves closer to the Sun as a result of which Earth will enter into a moist greenhouse effect.
Due to the overall decrease in the Sun's surface temperature, its habitable zone will shrink significantly.
Planet Mars will be completely within the habitable zone.
It stays in the same place.
It moves away from the Sun and becomes wider.

Europa is located outside the Sun's habitable zone and yet may be habitable. How can this be?:

Europa's subsurface ocean contains lots of minerals that allow water to remain liquid at much lower temperatures
Europa is continually being hit by comets and asteroids which keeps water beneath its surface liquid
Europa is tidally heated, allowing liquid water to exist beneath its icy surface
Europa is large enough to have appreciable heat trapped inside it to keep water beneath the surface liquid
Europa has internal heating mechanism due to high density molten rock in its core

The moist greenhouse effect refers to:

the natural greenhouse effect due to clouds of water vapour in the lower atmosphere
the region roughly halfway between the orbits of the Earth and Venus
the warming process by which water vapour rises into the upper atmosphere above the ozone layer where it is then broken apart by ultraviolet radiation
an enhanced greenhouse effect above tropical regions of the Earth's surface
the point at which water is evaporating from the surface at a faster rate than it is condensing