Robots Astronauts And You

Robots,*
Astronauts,**
and You***
Exploring
Space with a
Computer!
BIKRANT ROY
October 2008
Picture from Orbiter space flight simulator:
International Space Station above New England
**
***
*
*
*
*

Robots, Astronauts, and You: Exploring Space
 How do robots help us explore space?
 What can astronauts do that robots can’t do?
 How can you explore space right now?
 Free space stuff! Stellarium, Orbiter, WorldWide Telescope…
 The future: To infinity and beyond?

Real space robots don’t always
look much like robots…

The discovery of galaxies was
first announced on January 1st,
1925 by Edwin Hubble, who
was the first astronomer to
prove that there were other
galaxies outside of our own
Milky Way.
Prior to his announcement, in
1922-1923, Edwin Hubble was
searching for Cepheid variables
(a type of star) and had found
them in the Great Nebula in
Andromeda (M31, pictured left).
He later found out that the
distance between the nebulae
was so far apart, that is could
not be apart of the Milky Way
galaxy.
This led to the discovery of
galaxies beyond our own.
Discovery and Creation

The creation of galaxies is a very mysterious topic as it is uncertain of how the
universe was created. The most common theory however, is the theory of the Big Bang,
which states that the universe expanded from a very dense state and continues to
expand today.
Another common prediction of how galaxies were created is that due to the uneven
distribution of hydrogen and helium (The Big Bang theory states otherwise), large
amounts of gas began to compress after a pull of gravity. This small density gas-cloud
began to develop in areas of higher density and then formed planets, stars, and galaxies.
This is called the monolithic collapse, and the speed of rotation depended on whether or
not what type of galaxy it would become. Typically, a faster spinning gas-cloud became
spiral galaxies. Another way of galaxies forming is the hierarchical formation, when larger
galaxies were made up of several small ones.

Types of galaxies
There are many different types of galaxies in our universe. The main
types, however, are the spiral galaxies, elliptical galaxies, and
irregular galaxies. A fourth type, dwarf, can also be found, though
they are relatively small compared to the other types.

Elliptical galaxies are galaxies
that feature a ellipsoidal shape
and contain more middle aged
stars and very little gas and
dust. They can also have
different shapes that range
from round, flattened, and
elongated (which is the most
common by 60%).
These galaxies are believed to
be created by a collision
between two comparable
galaxies. It is also believed
that at the centre of these
galaxies lies a super massive
black hole. They make up
about 10-15% of the total
number of galaxies in the
Local Group and are often
found in the center of galaxy
clusters.
I. Elliptical Galaxy

The appearance of spiral galaxies are
very easy to distinguish. They feature a
shape that looks like a disk that usually
has a bulge in the center and with arms
that spiral outwards as the galaxy
rotates. The most common spiral
galaxies in our universe are the Milky
Way Galaxy (the one we are in), and the
Andromeda Galaxy (our nearest
neighbor). Combined with Irregular
galaxies, they make up 60% of the total
amount of galaxies in the Local Group.
However, unlike elliptical galaxies, they
are usually not found in the centre of
galaxy clusters. They do, however, also
consist of a super massive black hole in
its bulge. In a spiral galaxy, the younger
stars are found in its arms. Spiral
galaxies can easily be confused with
barred spiral galaxies, which look similar
but has a double ‘barred’ bulge. In 2005,
it was considered that our Milky Way
Galaxy falls under this sub category.
Spiral Galaxy

III. Irregular and dwarf
galaxies
Irregular galaxies do not have a
regular shape, hence the name
‘irregular’. They are very uncommon
within our universe though they are
believed to once be spiral or elliptical
galaxies that were altered by a
gravitational pull. Irregular galaxies
contain an abundant amount of gas
and dust. Examples of irregular
galaxies include Whirlpool Galaxy,
Hoag’s Galaxy, Cartwheel Galaxy
and Tadpole Galaxy.
Dwarf galaxies, on the other
hand, contain a very few
amount of stars compared to
our galaxy. They can have
up to billions of stars. They
are though to be formed by
gases lacking metals (as
opposed to regular galaxies
contain metal gases) There
are many dwarf galaxies in
the Local Group, and they are
known to orbit larger galaxies
such as the Andromeda
galaxy and the Milky Way (14
are known to orbit it). An
example of a dwarf galaxy is
Large Magellanic Cloud,
which holds about 30 billion
stars.

The milky way galaxy
The Milky Way galaxy is where our planet, Earth, the solar
system, the Sun, and about 200-400 billion other stars are
located. The diameter of the Milky Way is 100,000 ly (light years)
and the thickness is about 1000 ly. In case you didn’t know, one
light year is equivalent to about 10 trillion kilometers.

The oldest star that has been
found in the Milky Way is about
13.2 billion years old, which is
believed to be about the age of
the universe. That being said,
astronomers consider that the
Milky Way was one of the first
galaxies to be formed after the
Big Bang. It is also considered to
be a double barred spiral galaxy
(as mentioned before).
After watching the brief video,
you can see that there are many
stars in our galaxy that are quite
large, and to put things in
perspective and to compare, if
we were to shrink our solar
system (all the planets and our
Sun), and reduced it to the size
of a quarter, the galaxy would be
the size of the width of the
U.S.A.
Also, the weight of our sun is
believed to hold 99.8% of the
total mass of our solar system.
Travelling at the speed of light,
which is about 300, 000 km/s, it
would take many years for the
human species to travel the
Milky Way.

The Andromeda Galaxy (M31)
is named after the Greek
mythology of Princess
Andromeda. It is the Milky
Way’s nearest neighbor in
space, meaning it is the closest
galaxy to ours, though it is
about 2,500,000 light years
away. The galaxy is about 1.5
times bigger than ours and was
first seen by the naked eye in
964 A.D by a Persian
astronomer named Abd Al-
Rahman Al Sufi. It was then
later discovered by a telescope
in 1612 by Simon Marius.
Because of its larger size,
Andromeda is believed to
consist of more dark matter and
also has two black holes in the
center (as opposed to one in
many other galaxies).
Andromeda is a very special
galaxy to us as it travels at the
speed of a bullet, and
eventually, in the next 4.5
billion years or so, it will collide
with our own galaxy, the Milky
Way, and will likely create a
gigantic elliptical galaxy.

Galaxy
collisions
The Big Band Theory states that the Universe began a long time ago, with galaxies and
early stars forming just after. It also states that the Universe is still expanding today,
meaning that the galaxies that we see today are travelling at high speeds. Eventually,
sooner or later, these galaxies will collide, and since galaxies are mostly made up of
dark matter, the stars spread out are actually so far away that when a collision occurs,
most will be unaffected. However, the Andromeda galaxy and the Milky Way galaxy will
soon meet this fate, and as said before, they will create a gigantic elliptical galaxy. When
one galaxy meets another, the gas becomes so compressed that a large amount of new
stars will be born. There is also another fate, and that is when a very large galaxy
collides with another. This collision would make the larger galaxy add new stars and
become larger.

Inside of
galaxies
Ever wondered what was inside
a galaxy? Well look no farther,
because you’re in one!
Unfortunately, galaxies are
massive, and we can’t see as
much as we wish, and that is
why with the assistance of
telescopes, astronomers have
been able to identify certain
things in space. Our galaxy (the
Milky Way, in case you didn’t
know), is made up of stars, gas,
dust, a super massive black hole
(that not even light can escape
its gravity), a Quasar (in other
galaxies), and a large amount of
dark matter. And by large, we
mean, large. Stars, as big as
they are here, contribute to only
10% of what our galaxy is made
up of. The rest, you ask?
Everything else. And most of that
is dark matter, an unknown
substance that makes up most of
a galaxy’s mass.

The stars in a galaxy are
often sorted into two
classifications, which are
population 1 and population
2.
Population 1 stars are
younger stars that are rich
in elements and are usually
located along the arms of
galaxies. Meanwhile,
population 2 stars can be
as old as the universe and
have a very small amount
of elements in them.
Interstellar Medium (ISM) is
the amount of space
between the stars and the
galaxies. Since galaxies
are also made up of gas
and dust, they fall under
ISM, in which 99% of it is
gas (90% of hydrogen) and
only 1% of dust. This gas
and dust can range in
temperatures and can be
as cold as -410F. Nebulae,
is then created by clouds of
gas.
Stars, gas, and
dust in the
galaxies

Quasars
Galaxies that have nuclei that
produce a spectral line emission
are formed from highly ionized
gases. This is called a quasar,
and can fall under the class of
“Seyfert galaxies”. They are
found in active galaxies (most
often spiral), and emit high-
energy radiation in the form of x-
rays. The appearance of
quasars is truly unique, as they
have an extremely bright nuclei,
and spectra which have very
bright emission lines of
hydrogen, helium, oxygen and
nitrogen. Quasars are about a
trillion times brighter than the
sun and are believed that they
obtain their energy from black
holes. The size of a quasar is
very large as well, and can be
large in our entire solar system!
Finally, the energy from a quasar
can take billion years to reach
us.

The Local group
We’ve already talked about
the Andromeda Galaxy
and how far it is. Now,
zooming out a little more,
we come to something
known as the Local Group.
It is a collection of over 36
galaxies that consist of all
the different types. The
galaxies all cover about a
10 million light year radius.
Its two largest members
are the Milky Way and the
Andromeda Galaxies
(pictured left). Of all the
galaxies, only 3 are spiral,
13 are dwarf elliptical, and
the rest are irregular
galaxies.

And to think our journey
barely started yet…

Star Clusters
Star Clusters are groups
hundreds of thousands of
stars in the universe. There
are 2 types of star clusters
in the universe, Globular
Clusters and Open
Clusters. Globular Clusters
are groups of hundreds of
thousands stars that are
very old. Open Clusters
have fewer stars than
Globular Clusters and the
stars are much younger
than the stars in Globular
Clusters.

Globular
clusters
Globular Star Clusters
are roughly formed
spherical and consist of
older yellow and red stars
which are 12-30 billion
years old. Globular
Clusters are packed
together very tight rather
than Open clusters where
the stars are just
scattered and loose. Our
galaxy the Milky Way has
about 150 Globular
Clusters. Some Globular
Clusters can be seen with
the naked eye like Omega
Centauri.

Open
clusters
Open Clusters are somewhat different from Globular Clusters. Open Clusters
are confined to be a galactic plane and they are always found with spiral
arms. Open Clusters contain a few hundred members and are dominated by
young blue stars. These stars only live up to ten million years.
Open Clusters have much less stars than Globular Clusters.

Hubble Space Telescope (HST)
Is Hubble a robot? Yes, because it takes complex orders from
engineers on the ground that it can remember and follow on its own.
Its pictures of faint distant objects often take hours to record – HST
must keep itself pointed exactly at the target as it orbits the Earth.

From the web site http://hubblesite.org/gallery/album/

The Famous Mars Rovers…
Spirit and Opportunity have been roving Mars since January 2004,
on a mission that was planned for only 90 sols (Mars days) – they
have traveled for miles and have made many discoveries, including
various signs of water that flowed millions of years ago when Mars
was apparently a much wetter planet than now.

…and the women who drive them!
JPL, March 18, 2008 – an all-woman Mars Rover science/engineering team

Cassini: Our robot eyes at Saturn
Cassini was launched in 1997 and started orbiting Saturn in 2004.
It dropped off a smaller robot called Huygens to land on Saturn’s
cloudy moon Titan. Cassini’s orders are complicated, and it has
taken thousands of detailed pictures of Saturn and its many
moons.

Phoenix: Our latest robot on Mars
Right now, Phoenix is digging into the soil near the
north pole of Mars, looking for ice (it found it) and for
chemicals that could be signs of ancient Martian life.

How robots help us in space
• Robots don’t need oxygen, water, or food, so they
can go on very long trips (they do have to carry
rocket fuel and they usually get their electrical
power from the Sun using solar panels)
• They are “smart” enough to do some things on
their own (like avoiding dangerous situations),
though current robots usually can’t change plans
or make creative decisions on their own
(engineers on Earth can help them solve
problems and make changes in their missions)
• They can carry many kinds of cameras and
instruments and send their images and scientific
findings back to Earth by radio signals

Do you know Buzz?
Lightyear
(in Toy Story)
Aldrin
(in Lunar Module)

The Real Buzz!
Buzz Aldrin at Tranquility Base, July 1969

Astronaut Accomplishments
• Men and women from the USA, Russia,
and other countries have been flying in
space since 1961 and have proved that
humans can live and work successfully in
space, even for months at a time
• They have explored the Moon, repaired
broken satellites, done many scientific
experiments, and built the huge
International Space Station (ISS) that you
can see sometimes as a bright, fast
moving object high in the evening sky
• They have often had to invent clever
solutions and improvise new procedures
when things have gone wrong in space

Apollo 17 Astronauts on the Moon
Apollo 17 was the last Moon landing to date (December 1972).
Commander Gene Cernan (left, with Lunar Rover) and geologist
Jack Schmitt (with flag) spent 3 days on the Moon, driving for
miles and changing their exploration plans based on what they
found. They discovered important clues to the history of the
Earth-Moon system.

Astronauts repairing Hubble
The Hubble Space Telescope was launched in 1990 and was
designed so that shuttle astronauts could later upgrade it in orbit.
But it had a mistake in its telescope optics, so in 1993, the first
service mission was used to repair it so it could take good pictures.
Later missions upgraded its ability to reveal the secrets of the
Universe by studying faint objects billions of light years away.

Robots and Astronauts Team Up
Robots are already helping astronauts in space. The shuttle and
the ISS have big “robotic arms” that allow astronauts to move huge
objects and be moved around easily for space walks. This is a new
multi-arm robot called DEXTRE that’s on the space station now.

Coming up… ROBONAUT!
To help astronauts on future missions, NASA is developing an
experimental human-shape robot called Robonaut. It will be able
to fit in spaces made for humans, and even use tools made for
human astronauts. It will probably operate at first by
“telepresence” where it will act as the eyes, arms, and hands of
an astronaut who is sitting safely inside the spacecraft.

So where do YOU fit in?
• Exploring space requires a lot of people
working together – there are many
different jobs to do: it’s not just about
astronauts!
• Engineers, scientists, technicians,
teachers, computer & robot programmers,
managers, and astronauts work together
to make space exploration possible
• Private and commercial space flight is
expanding, so there will probably be more
space-related jobs in the future
• But what can you do right now?

Explore space
with a
computer!

Explore Space on the Web
Check out www.nasa.gov – they have TONS of
great stuff on the web for every age and interest!

Watch the Astronauts Work
NASA TV is available for free on the web (www.nasa.gov/ntv)
and on some cable TV systems. During shuttle and ISS
missions, they broadcast live coverage of the launch, docking
with the space station, astronaut space walks and other tasks,
and landing. You can learn a lot from watching the astronauts
work!

Explore Software Simulations
• Real astronauts,
scientists, and
engineers train with
various types of
computerized
simulations to learn
and practice their
complex jobs
• Software space and
astronomy simulator
programs are
available to use on
your own computer
(they don’t include
cockpits like this!)
• Some of the best
ones are available
for free on the web!
NASA Space Shuttle simulator
flight deck (fisheye lens view)

Stellarium – Your Free Planetarium!
www.stellarium.org

What is Stellarium?
 Stellarium is a planetarium simulator program
available for free download to install and run on
PC and Mac computers
 Once it’s installed, it doesn’t require a web
connection to use – if you’ve got a notebook PC
or Mac, take it outside on a clear night to help
you identify things you see in the sky!
 Stellarium gives you an easy to control view of
the sky as it looks from your back yard right
now or at any time or place that you set up
 It helps you identify stars, planets, nebulae,
constellations, and more

New! WorldWide Telescope
New and free from Microsoft is WorldWide Telescope, a wonderful
planetarium and astronomy exploration tool. After installation, it still
requires a web connection to access and display a wide range of
astronomy images from many sources, and includes narrated tours and
much more. www.worldwidetelescope.org (Windows only).

Orbiter – Free Space Flight Simulator!
www.orbitersim.com

What is Orbiter?
Orbiter is a free space flight simulator, a
game-like program with 3D graphics that
makes you a “virtual astronaut” in the
cockpit of a simulated spacecraft
Unlike most “space games” for PC’s or
game consoles, Orbiter is based on real
science, so spacecraft behave the way
they really do in space
It’s fun to learn to change your orbit,
launch into orbit from Earth, land on the
Moon, dock with a space station, and
much more

Orbiter Sample Screens
Docking with the space station
in the Deltaglider, a cool
futuristic space plane that you
can fly yourself in Orbiter

Go Play In Space – free e-book!
www.virtualspaceflight.com

The Future of Space?
• Space exploration helps us learn about the universe
and has also helped us develop many important
technologies like computers, weather satellites,
GPS, and even cardiac monitors
• Private companies are now working on ways to
make money from space, including space tourism
and eventually building solar power satellites and
even mining the Moon and asteroids
• In making use of space, we are still at a very early
stage – who would have predicted a Boeing 747
from the Wright Brothers’ 1903 airplane?
• Earth is tiny, space is huge, and space has
abundant materials and energy we can eventually
use to support human civilization
• One promising and important use of space
technology: figuring out a way to keep an asteroid
from hitting the Earth as has happened in the past

The Distant Future?
"Since, in the long run, every planetary civilization will
be endangered by impacts from space, every surviving
civilization is obliged to become spacefaring – not
because of exploratory or romantic zeal, but for the
most practical reason imaginable: staying alive. If our
long-term survival is at stake, we have a basic
responsibility to our species to venture to other
worlds."
Carl Sagan, Pale Blue Dot, 1994

Conclusions
 Robots and astronauts are both
important for space exploration,
and in the future, they will work
together even more as we go back
to the Moon and on to Mars
 There are many interesting jobs
related to space other than
astronauts, and as private
companies start to do more in
space, there will probably be more
 You can use free software like
Orbiter, Stellarium, and World
Wide Telescope to have fun and
learn about space and astronomy
now, but remember…
 The future is exciting, but space is
also beautiful and available to see
on any clear night – go outside and
explore space now!

Join a Space or Astronomy Group
• You can learn more and help support space
exploration by joining a space society
– National Space Society (www.nss.org) supports
human and robotic exploration
– The Planetary Society is focused on robotic
exploration of the planets (www.planetary.org)
• You can also join a local astronomy club like
the Aldrich Astronomical Society in the
Worcester, MA area (www.aldrichastro.org)

Supplemental Slides
What Can You Do With
Orbiter?

Visit the Moon in the future…

…or the past.
Apollo Lunar Module (LM) and Lunar
Rover in AMSO add-on for Orbiter
(Apollo 17 is shown)

…one of its small moons,
View from Mars orbit, 54 km from Phobos, one of Mars’ two tiny moons

…or something a bit bigger.
Jupiter with its volcanic
moon Io in the foreground.

Launch the Space Shuttle…
Space shuttle Atlantis, 89 seconds after launch, with visible force vectors

Grab the Hubble Space Telescope...
Shuttle approaching the Hubble Space Telescope for repairs fall 2008

…or dock with the Space Station.

How does he do that?
(with thrusters – Rotation vs. Translation)

25/01/15
The Solar System and BeyondThe Solar System and Beyond

25/01/15
Solar systems, galaxies and the Universe
OUR SUN is one of
millions of stars that
orbit the centre of…
THE MILKY WAY,
which is one of a billion
galaxies that orbit AND
move away from the
centre of…
THE UNIVERSE

25/01/15 The Milky Way is the name of our galaxy

25/01/15
There are eight planets in our solar system:
Mercury
Mars
Jupiter
Saturn
Neptune
Uranus
Pluto
Venus
Earth

25/01/15
But what do we know about the Sun?But what do we know about the Sun?
The Sun is 150 million
kilometres away from
us.
The temperature of
the Sun's surface is
6,000 degrees.This is
the same temperature
as the Earth's core.
However, the
atmosphere heats up
to millions of
degrees.

25/01/15
Fast facts about MercuryFast facts about Mercury
• Distance from Sun: 57 million kilometres.
• Maximum temperature: 465 º
• Minimum temperature: -184 º
• Volume : 5% of the Earth
• Satellites: Mercury has no satellites.
• Mercury is the smallest planet in our
Solar System.
• Mercury is a world of extremes: it’s
extremely hot during the day and it gets
very cold in the night. That happens
because it spins very slowly (one rotation
lasts 58 days).

25/01/15
Fast facts about VenusFast facts about Venus
• Distance from Sun: 107 million
kilometres.
• Average temperature: 449 º
• Satellites: Venus has no satellites..
• Venus is a hostile planet. Its thick
atmosphere (with clouds of sulfuric acid)
makes it impossible to see the surface.
• In many ways Venus is similar to the
Earth. It has active volcanoes,
mountains and valleys.
• Venus is unusual because it rotates in a
direction opposite that of all of the
other planets.

25/01/15
Fast facts about the EarthFast facts about the Earth
• Distance from Sun: 150 million
kilometres.
• Average temperature: 7’2 º
• Satellites: The Earth has one
satellite: the Moon..
• Our planet is an oasis of life in a
desolate system. The Earth's
temperature, weather, atmosphere
and many other factors are perfect
to keep us alive.

25/01/15
Fast facts about MarsFast facts about Mars
• Maximum temperature: 36º
• Minimum temperature: -123º
• Satellites: Mars has two satellites, Deimos and
Phobos..
• Scientists think that Mars once had rivers,
lakes, and even an ocean.Today the only water
on Mars is frozen in the polar caps, or
underground.
• Mars has many craters which were formed by
meteorites or asteroids. Mars also has some of
the tallest volcanoes and some of the deepest
valleys in our solar system

25/01/15
Fast facts about JupiterFast facts about Jupiter
• Average temperature: -153º
• Volume : 1,318 times more than the Earth
• Satellites: Jupiter has at least 63 satellites.
The most important of them are Io, Europa,
Ganymedes and Callisto..
• In Jupiter, you can see a great red spot; it’s a
giant storm that has lasted for hundreds of
years. This storm's super hurricane winds blow
across an area larger than the Earth.
• This giant planet has no solid surface. Under
its atmosphere is a large liquid ocean of
hydrogen and water.

25/01/15
Fast facts about SaturnFast facts about Saturn
• Distance from Sun: 1,429 million
kilometres.
• Volume : 744 times more than Earth
• Satellites: Saturn has 61 satellites.
Some of them are Calypso, Rhea and
Titan..
• Saturn's atmosphere has winds which can
blow at over 1800 kilometres per hour.
• Saturn is surrounded by over 1000 rings
made of ice and dust. Some of the rings
are very thin and some are very thick.

25/01/15
Fast facts about UranusFast facts about Uranus
• Distance from Sun: 2,871 million kilometres.
• Satellites: Uranus has 27 satellites.
• Unlike all the other planets in our Solar System
Uranus spins on its side. It is believed that
long ago a very large object smashed into this
planet. The crash was so powerful that it
completely changed the direction of Uranus'
spin.
• Uranus may have an ocean of water beneath its
clouds. It has a large rocky core, and because
of the tremendous pressure could possibly
contain trillions of large diamonds.

25/01/15
Fast facts about NeptuneFast facts about Neptune
• Distance from Sun: 4,496 million
kilometres.
• Satellites: Neptune has at least 13
satellites.
• Neptune has winds in its atmosphere
which blow at over 2000 kilometres per
hour! This planet has large, dark circles
on its surface which astronomers believe
to be storms .

25/01/15
The moon orbits the Earth...The moon orbits the Earth...
Sun
Earth
moon
...as the Earth orbits the Sun....as the Earth orbits the Sun.

25/01/15
The Earth orbits the sun every…The Earth orbits the sun every…
……year (365year (365 11
//44 days)days)

25/01/15
The Earth is kept in orbit by the force of…The Earth is kept in orbit by the force of…
GravityGravity
…and by the fact
that is is moving at
a high velocity

25/01/15
Gravity also keeps the moon in orbit around the
Earth. The moon orbits the Earth every…
……month (28 days)month (28 days)

25/01/15
As the Earth orbits around the Sun, it also spins
on its own axis

25/01/15
At any time, half of the Earth faces the sun
and therefore receives light.
The other half faces away from the Sun,
and so receives very little light.
This part is in night.
This part is in day.

25/01/15
What causes the Earth’s seasons?
As the Earth orbits the Sun, when its axis tips towards the Sun, the
weather gets warmer. When it tips away, the weather gets colder,
causing the Earth’s seasons.

25/01/15
The Earth is divided up into the northern hemisphere andThe Earth is divided up into the northern hemisphere and
the southern hemisphere:the southern hemisphere:
Equator
Northern
hemisphere
Southern
hemisphere

THE END
Name = Bikrant Roy
Class = Ninth ‘B’
Roll no. = 23

Robots Astronauts And You

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