Astronomy Midterm Flashcards
Whaat is the current age of the Universe?
13.8 Billion Years
How many known planets does our Solar System have?
8
Which is older, the Sun or the Milky Way?
Milky Way
Which is the most massive planet between Venus, Earth, Mercury, & Mars
Earth
An Astronomical Unit (AU) is
the distance from the Earth to the Sun
Exoplanet/ extrasolar planet
Planet that orbits a start other than our sun
Raidal Velocity Method of detecting Exoplanets
Subtle rocking of a star back and for the as an unseen orbiting planet pulls on it
Doppler effect
Changes the wavelength (color) of the star’s light as is moves
Transit Photometry method
Look for the dimming of a star’s light as an unseen planet moves in front of it.
The doppler effect will
Change the wavelength (color) of light emitted by a star
A “face-on” planetary system will
not be detectable by transit or radial velocity methods
For a given sized star, the larger the planet the
larger the transit dip
Most planets today have been detected with
NASA’s Kepler sattelite
T/F The transit photometry method of detecting extrasolar planets is an indirect method of detection
True
Kupier Belt
Sea of icy bodies, like Pluto
Oort cloud
resoivoirs for comets
Comets
leftover after the construction of our solar system’s planets
Halos
As a result of their icy composition, when comets come close to the Sun and get hotter, they become “active” as their ice sublimates (changes from solid to gas), releasing gas and dust, creating the distinctive fuzzy halo (known as a coma) and tails that we associate with comets.
Main belt comets come from the
asteroid belt
Comets come from
Kuper belt, icier parts
Star nearest to the sun
Proxima Centauri
Sun’s nearest neighbors
Brown Dwarfs, balls of gas too big to be called planets but too small to be called stars.
What two planets have ammonia clouds in the upper atmosphere
Jupiter and Saturn
Which compound gives Uranus and Neptune their bluish appearance?
Methane (CH4)
It’s the movement of objects in ______ that cause scientists to predict the presence of a “planet 9” in our Solar System.
Kuiper belt
The Planet 9 citizen science project has already discovered
a Brown dwarf
Sublimation is the process where a
solid turns into a gas
Mars’ atmosphere is mostly
carbon dioxide
Fans and blotches are caused by gas sub-surface gas erupting through a layer of ___ ice.
carbon dioxide
T/F Mars was not able to have liquid water (H20) on its surface at any point in the past due to its very low pressure atmosphere.
False
If Earth, Mars, and Mercury all started out at the same temperature, which do you think would cool off faster?
Mercury
What objects cool off faster
Smaller ones
How do Spiders form on Mars
Like a geyser through sublimation
How does swiss cheese form on mars
Repeated cycles of condensation and sublimation of CO2
What is the approximate age of the Earth?
4.5 billion years
Where is Earth’s magnetic field created?
Outer core
In what layer of Earth’s atmosphere does the majority of our weather occur?
Troposphere
The Dvorak Technique
is used to estimate the intensity of a tropical storm
Sporadic meteors are created
by asteroids.
Major layers of Earth
Core, mantle, crust
Astenosphere
upper layer of mantle, allows for slow convection currents to form as heat to surface, varied topography
Trophosphere
Layer closest to surface,
Stratosphere
Layer above Trophosphere, source of heat is above
Ozone Layer
absorbs dangerous UV light from SUn , heats the starosphere
Mesosphere
Convection because it’s heated from the ozone layer above
Thermosphere
Space, Meterors feel friction
meteoroid
solid object moving in interplanetary space
meteor
visible phenomenon resulting from the passage of a meteoroid into the Earth’s atmosphere
meteorite
solid piece of debris which has survived the passing of a meteoroid through the Earth’s atmosphere and falls on the ground
Which layer of the Sun is closest to the surface?
Convective zone
What is the source of the Sun’s energy?
Nuclear fusion
What is the name of the visible surface of the Sun?
Photosphere
Approximately how many times more massive is the Sun than the Earth
300,000
Sunspots are warmer than the surrounding gas.
False
root source of all of the energy sources that we use to power our civilization
Sun
uminosity of the Sun
38 with 25 zeros after it!
radiative zone.
all of the hydrogen gas is ionized, meaning that the protons and electrons are not bound together
Most of the mass in the Universe was in the form
Dark Matter
cosmic microwave background (CMB).
At this time, the cosmic light, which before then would get continuously scattered off of the charged particle, could not travel freely throughout the Universe. We can still see this light today as a faint glow of microwaves called the
dark ages
gas was pulled into larger and larger clumps by the gravitational force of Dark Matter
largest of these terrestrial planets,
Earth
e second largest terrestrial plane
Venus
the third largest terrestrial planet)
MArs
Jovian planets, or gas giants,
Jupiter, Saturn, Uranus, and Neptune
Sunspots exist on the surface of the Sun called the
Photosphere
what kind of ice forms on Mars’ northern and southern poles?
CO2 or “dry ice”
what kind of gas erupts from the ice to create ‘fans’ and ‘blotches’?
CO2 gas
what season does the gas erupt? on mars
Spring
rue/False, Swiss Cheese terrain are channels carved into the surface of Mars that are revealed when the surface is ice-free
False, this is what Spiders are
