Dwarf Planets and Asteriods Flashcards
Why would Dawn have gone to Vesta but not Pallas
Pallas has a high orbital eccentricity which makes it relatively inaccessible
What is the naming convention for Jovian trojans
what is the numerically amazing fact about Jovian trojans
Ones at L4 are named after Greeks in the war
Ones at L5 are named after Trojans in the war
There may be as many Jovian trojans as there are asteriods in the main belt
What are the names of Pluto’s moons
Charon (1978)
Nix (2005)
Hydra (2005)
Kerberos (2011)
Styx (2012)
who discovered Charon
what is its diameter
James Christy
1207km
What are the five known dwarf planets
Ceres (1801)
Pluto (1930)
Haumea (2004)
Makemake (2005)
Eris (2005)
What is the name of the classical Kuiper belt objects which lie in orbits untouched by Neptune (as opposed to the resonant Kuiper belt objects)
cubewanos
What is the current estimate for the diameter of Pluto (and Eris for comparison)
Pluto - 2372km
Eris - 2326km +- 12km (but Eris is denser and more massive)
What is the smallest dwarf planet
diameter?
an distance from sun in AU
Ceres
938km
2.77 AU
What is the name for the objects that exist 30 to well beyond 100 AU with high orbital eccentricities, as a result of gravitational affects of the gas giants
Scattered Disk Objects (SDOs)
When was Chiron discovered, and how big
what was it the first of to be discovered
1977
233km
First Centaur to be discovered
Centaurs are minor planets orbitting the asteriod belt and the Kuiper belt
Chiron is named after the Centaur Chiron in Greek mythology
What are the most common types of asteriods
What is the largest of this type
What are the other principle types
C-type carbonaceous
Hygiea
Ceres is a C-group, G-type
S-type (stony objects)
M-type (metallic objects)
What do you call a minor planet or moon that shares an orbit with another larger object but doesn’t collide -
and why doesn’t it collide
Which planet has the only known satellites bearing these objects
When was one discovered around earth
a Trojan
It doesn’t collide because its at a Lagrangian point (L4 or L5) 60degrees ahead and behind the main body
Saturn
in 2011 NASA announced earth had a trojan 2010TK7 (300m diameter in L4 position 60 degrees ahead of earth)
What spacecraft is in orbit around Ceres
when did it get there
when was it at Vesta
Dawn
6 Mar 2015
Vesta - 16 July 2011
What are the 5 biggest asteriods (and dwarf planet) in the asteriod belt in terms of diameter
Ceres
Pallas ( but its less massive than Vesta)
Vesta
Hygiea
Interamnia
In terms of AU, how far out is the Kuiper belt
how big is it compared to the asteriod belt
What are the three dwarf planets in the Kuiper belt
What two interesting moons are thought to have originated here
30-50 AU
20 x as wide and 20-200 times as massive as the asteriod belt
Pluto, Haumea and Makemake
Triton and Phoebe
What comet studying mission was launced on Ariane 5 in March 2004
What was the name of its lander
Rosetta
Philae
What comet did R reach, and when did the lander perform its historic touch down
When did the lander wake up
For kudos what other major asteroid did R do a flyby of (and when)
67P / Churyumov-Gerasimenko
12 Nov 2014
14 June 2015
Lutetia (July 2010) - named after the Roman name for Paris
What is particularly special about Vesta
It is also the brightest asteroid visible from earth
Who discovered Ceres and when
Why was it called Ceres
Under what circumstances did he discover it, and who else was looking for it
Giuseppe Piazzi at Palermo on 1 January 1801
Ceres was the Roman patron goddess of Sicily and Piazzi was from the University of Palermo
He was working on a catalogue of fixed stars, when one of his stars moved!
Baron Franz Xavier von Zach of Gotha, convinced of a planet Mars and Jupiter, assembled a group of leading astronomers in 1800, in Germany, with each taking a piece of the sky to survey. They called themselves the ‘Celestial Police’
Piazzi, was not connected, and his discovery was accidental
What is the diameter of Ceres
How many AU is Ceres from the Sun
938km
2.77AU
Who came up with the name ‘asteroid’ and why
William Herschel in 1802, because other than their rapid movement they appeared indistinguishable from stars. Therefore asteroid comes from asteroeides meaning “star-like”
but they continued to be called planets from several decades - this was only dropped once so many had been found in the early 1850s
Who discovered Pallas, and when
What else did he famously discover and when?
Under what circumstances was Pallas discovered
Heinrich Olbers in 1802
He also discovered Vesta in 1807
Olbers was one of two astronomers who had confirmed that Ceres was an asteroid. It was whilst attempting to locate Ceres that he noticed Pallas, coincidentally passing Ceres at that time. (It first it was estimated to be 3,380km in diameter - how wrong eh)
Can you name all the Planets as known between 1807 and 1845
Mercury, Venus, Earth, Mars
Vesta, Juno, Ceres, Pallas
Jupiter, Saturn and Uranus
What probable Dwarf Planet is known as the anti-Pluto because it is locked in the same resonance, but is out of phase (i.e. at aphelion when pluto is at perihelion), and with orbit points almost opposite direction from pluto’s
What is the name of its large moon
Orcus (The Etruscan equivalent of Pluto - and later an alternate name for Pluto)
Vanth
Which dwarf planet is most notable for its elipsoid shape
Haumea
(It was the one which has the moon, informally known as a Santa)
Now its known to have two moons, Hi’aka and Namaka
Where was the discovery of Pluto made
Who proposed the name
Lowell Observatory
Venetia Burney (1918–2009), a then eleven-year-old schoolgirl in Oxford, England, who was interested in classical mythology
(he suggested it in a conversation with her grandfather Falconer Madan, a former librarian at the University of Oxford’s Bodleian Library, who passed the name to astronomy professor Herbert Hall Turner, who cabled it to colleagues in the United States.)
How far out is Eris in AU
What was it known as informally before being called Eris
97.6 (one of, if the not the furthest object in the solar system known - although it is nearly at Apehelion)
Xena (after the warrior princess)
What is a Dwarf Planet
A dwarf planet is a planetary-mass object that is neither a planet nor a natural satellite. That is, it is in direct orbit of the Sun, and is massive enough for its shape to be in hydrostatic equilibrium under its own gravity, but has not cleared the neighborhood around its orbit
Because only Pluto and Ceres have been observed well enough to confirm this, others have been confirmed on other grounds
Eris, becuase its more massive than Pluto
and Makemake and Haumea, because at the time they were the suffiently bright, considering reasonable expectations of albedo
It is controversial that the IAU has not granted more, equally justified objects, Dwarf Planet status
What was the date of Pluto’s perihelion
In what year did Neptune become closer to the Sun (and for how long in Pluto’s orbit is Neptune further away)
Sep 1989
11 Feb 1999 Neptune becomes closer
20 years
What is Pluto’s orbital period
248 years
How close is Charon to centre of Pluto?
For kudos, who close to the Barycentre
19,571km to centre of Pluto
17,526 km to Barycentre (mean)
What is the mean distance in AU of Pluto from the Sun
for Kudos, how close does it get, and how far away does it get
With what angle is its orbit inclined to the eliptic
39.4AU (remember just a bit under 40)
close as 29.7AU (just remember just under 30 as good enough)
as far as 49.7AU (just remember just under 50 as good enough)
17 degrees
What is a Plutino
What type of object is in a 1:2 resonance with Neptune
A Plutino is a KBO in a 2:3 resonance with Neptune
A Twotino is in a 1:2 resonance
What is ‘the Kernel’?
What hypothesis might it support?
The Kernel is an anomalous concentration of icy objects in the Kuiper belt at 44AU.
It has low inclination and low eccentricities, and was initially thought to be a result of a collision in the Kuiper belt. However, this explanation has some signficant difficulties.
Another hypothesis is that the cluster was once gravitionally associated with Neptune, but got seperated during a gravitional interaction between Neptune and a third hypothetic ice giant called Hades as it was ejected from the solar system
What is the orbital inclination of Pluto
17.14 degrees
What is the inclination of equator (spin axis) of Pluto
-57.47 degrees
What is Pluto’s rotation period
6.39 days
What was the name of the famous meteor caught on dash cams over Russia (when)
How big was it
Chelyabinsk meteor - 15 Feb 2013
(it caused Over 7,200 damaged buildings, collapsed factory roof, shattered windows)
It was a 20m diameter impactor with a mass of abour 12-13,000 tonnes - it was equivalent to 500kt of TNT
What famous meteor shows do you associate with the following months
August
December
August - Perseids
December - Geminids
What asteriod family is believed to have been the source of the asteroid that wiped out the dinosaurs
What type of asteroids are these.
What is the main asteroid, and what is its other claim to fame
Flora
S - Silicaceous (stony) asteroid
Flora is the name of the large asteroid (136x136x113km)
It is the closest of the large asteroids to the Sun
What Japanese mission arrived at an asteroid in 2018
What was the name of the asteroid
What is the name of the landers involved
Hayabusa 2
Ryugu
The landers are Minerva-II (1) & (2) and Mascot
What is the name of the Japanese Mission that arrived at an asteroid in 2005
What was the name of th asteroid
Hayabusa 1
Asteroid Itokawa
What is the main determinant of an asteroids composition
In what way
How close it is to the Sun
- The asteroids that are nearest the sun are mostly made of carbon, with smaller amounts of nitrogen, hydrogen and oxygen,
- The ones further away are made up of silicate rock.
What diamond shaped asteroid was reached in 2018, and what was the name of the spacecraft that reached it.
What is the nickname of its funny bump
Why is this asteroid important
Bennu (500m diameter) - and its funny bump ‘witch mole’, because it was reached near halloween and it looks like a witches mole.
Reached by Osiris-Rex spacecraft
Its an important asteroid, because it crosses earth’s path, and could hit earth in the next few centuries, so scientists want to discover as much about it as possible.
What is this, and when was it reached
Arrokoth
It had the unofficial name Ultima Thule (pronounced ‘Tool-ie’) first, which is prob more memorable
Now its two lobes are being referred to as Ultima (the larger) and Thule (the smaller)
In its original use, the term Ultima Thule is ancient, first used during the Roman Empire and also popular during the medieval period, referencing lands that are both very distant and very cold
reached by New Horizons on 1 Jan 2019
