It was the first planet discovered in
modern times, by William Herschel in ?
Uranus is the
third largest planet (by diameter), larger in diameter than
__ but smaller in mass?
The planet rotates once every
___ hours and a Uranian year is ___ Earth years long
The material from the Uranus collision
didn't form a separate moon, but was absorbed back into Uranus and In addition to mass and kinetic
energy, the collision would also have contributed angular momentum
In relation to the Sun, Uranus and Neptune formed ________ .
closer in and then drifted outward, populating the Oort cloud.
Uranus and Neptune appear to have a blue or blue-green color, primarily due to the amount of ________ in their atmospheres.
Uranus still has
seasons: the south summer lasts for 1/4 of the orbit, about 21
years. Then gradually, for the next 21 years, the Sun would
appear over the equator, passing through equinox. Next, the
north pole of Uranus would be fully illuminated for about 21
years, and so on.
The Uranian atmosphere is composed of about __ percent
hydrogen, __ percent helium, __ percent methane, and tiny
amounts of ethane and other gases
83, 15, 2
Which planets have rings?
Jupiter, Neptune, Uranus, and Saturn
Neptune's largest moon, Triton is odd in the sense that
its orbital direction is retrograde
Uranus and Neptune are sometimes referred to as the ________ planets.
Both Uranus and Neptune have weak magnetic fields for their size, but the real oddity is that ________
the axis of the magnetic fields are both tilted relative to the rotation axis and offset from the center of the planet.
As of August, 2006, the International Astronomical Union considers Pluto not to be a planet but ________ .
a Dwarf Planet
Pluto's atmosphere ________ .
spends more than half of the orbit period condensed on the surface
Note that Uranus does not appear to
have an _______ and this is likely the reason for its rather boring atmospheric activity. (lack of bands)
Internal Heat Source
Miranda is about half ___ and half ___ and the surface is all mixed up with heavily cratered terrain intermixed with
weird grooves, valleys and cliffs
water ice, rocky material
Since the center of gravity
of the Pluto-Charon system is not within the body of Pluto, Pluto and
Charon are not considered to be planet and moon; they are
considered binary companions.
What is Charon?
How many moons does Pluto have?
Pluto's composition is unknown, but its density (about 2x water) indicates that it is probably a mixture of __% rock and __% water ice much like Triton
The Oort Cloud is more primordial than the Kuiper Belt.
The Kuiper-belt is the presumed source for ________ .
The first minor planet was discovered in ________
Objects with a 2:3 orbital period resonance with Neptune are called ________ .
The first (besides Pluto) TNO to be discovered was 1992QB1 discovered in ________ .
What orbital aspects do the Plutinos have in common?
They all share a 2:3 orbital period resonance with Neptune.
Comets originate ________
in the Oort-cloud and in the Kuiper-belt
A Meteor is:
A Meteor is a luminous trail in the sky produced when a meteoroid
burns up in the atmosphere.
This refers to the particle itself without relation to the phenomena it produces when entering the Earth's atmosphere and A
meteoroid is matter revolving around the sun or any object in interplanetary space that is too small to be called an asteroid or a comet.
Most Meteorites come from??
What are the 5 kinds of meteors?
Chondrites, Carbonaceous Chondrites, Achondrites, Iron Meteorites, Stony-Iron
Most common meteor
Most meteorites come from comets.
False, originate from dense rock bits in the asteroid belt
What is a meteor shower?
orbit happens to intersect the path of a recent comet, the debris trail will be dense, and one might see hundreds to thousands of meteors
Meteors come from...
Widmanstatten Patterns are?
are seen in iron meteorites and are metallic crystals that have cooled slowly (Nickle and Iron)
Asteroid belt is between what two planets?
Mars and Jupiter
Most asteroids are spherical and indifferent from one another
The Sun contains ________ of the mass of the entire solar system.
Stony meteorites are classified based on the presence, size, and chemical composition of small mineral grains called ________ .
A "shooting star" is actually a ________ .
How many tails do comets have?
Why are comets temporary objects
They melt as they get closer to the sun
Comets are pointed where?, Dust tails point where?
Towards the sun, Away from the sun
Comets are small, fragile, irregularly shaped bodies composed of a mixture of non-volatile grains and frozen gases
Periods of less than 200 years
Outside of Neptune, primarily short- period comets
A spherical shell of more than 100 billion
comets surrounds the solar system at a distance
of 1,000-100,000 A.U., called the ?
Have we been hit with an asteroid or meteor before? How Many?
The two impacts that we know of date back ______ years ago and _______ years ago
250 mill, 65 mill
Trans-Neptunian Objects, bodies>100 km in diameter in an orbit 30-50 A.U. from the Sun.
What objects are in the Kupier Belt?
Pluto, Charon and Triton
What objects have been detected in the Oort Belt?
Nothing but passing stars.
planetesimals are what?
Planets formed in the Solar Nebula from the slow accretion of small dust particles (via electrostatic forces) into 1-10 km size planetesimals
what are Planetary Embryos?
Most (but not all!) of the planetesimals merge to form
Planetesimals and Planetary Embryos grow larger because. . . .
The accretion continues, but fueled by the
gravitational attraction of the biggest planetesimals: The
big things keep getting bigger, swallowing up smaller
planetesimals near their orbit. The growing young planet
absorbs the mass and the orbital energy of all the smaller
objects, circularizing (averaging out) the final orbit.
Composition of planets is related to their distance from Sun:
What are Beta Pic stars?
Proto-planetary disks have been seen for more than three decades. First, stars known as Beta Pic stars, for their proto-type, Beta Pictoris, were known to have excess infrared radiation. The star, shown at left, looks like any other star
The matter rotated in a flattened plane, splayed out
in a disk due to what
conservation of angular momentum.
Do planets exist outside of our solar system? If so, what are their properties?
Yes, but we do not know, our technology does not allow us to detect this. We see there is something similar to Jupiter in size, but other than that, we can not detect if anything is like earth.
Kepler satellite is what?
is designed to monitor 200,000 stars in 105 square degrees of the sky over the next 4 years looking for these dips in brightness.
What techniques are used to discover planets around other stars?
One such technique examines the brightness of a star over time and looks for the tell-tale drop in brightness when the planet passes in front of the star, partially eclipsing it (called a "transit"). Only planets that orbit their stars seen edge-on from the Earth are eligible for this technique; <1%
Which Planet is most like our sun?
How long did it take our planets to form?
4.5 billion years