New Core CurriculumNew Core Curriculum

week 3, class-2week 3, class-2

Foundations of Scientific ProcessFoundations of Scientific Process

Visible Objects in the UniverseVisible Objects in the Universe

The Hubble Ultra Deep Field

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Hubble Space Telescope2.4m optical telescoperesides in orbit of Earth

The Hubble Ultra Deep Field

What objects do we see here?

• Planets: an object that orbits a star, is large enough to have settled into an object that orbits a star, is large enough to have settled into a round shape and dominates its orbital zonea round shape and dominates its orbital zone;

Objects in a Visible UniverseObjects in a Visible Universe

The Universe is defined as the summation of all particles and energy that exist and the space-time in/during which all events occur.

What is a Planet?What is a Planet?

Conventional (past) definition: Conventional (past) definition: Planet is a body that orbits a Planet is a body that orbits a star, shines by reflecting the star’s light and is larger than an star, shines by reflecting the star’s light and is larger than an asteroid.asteroid.

What observation ignited the debate about the definition of What observation ignited the debate about the definition of a planet?a planet?

Observation of the vast population of objects in the Observation of the vast population of objects in the vicinity of Pluto (Kuiper Belt Objects = KBO);vicinity of Pluto (Kuiper Belt Objects = KBO);

In particular, KBO Eris is larger than Pluto;In particular, KBO Eris is larger than Pluto;

If Pluto is a planet, not only Eris but also dozen of other If Pluto is a planet, not only Eris but also dozen of other KBO objects will need to be considered a planet. KBO objects will need to be considered a planet.

Key Feature: Key Feature: Planet is a body massive enough to dominate Planet is a body massive enough to dominate its orbital zone by a) flinging smaller bodies away , b) its orbital zone by a) flinging smaller bodies away , b) sweeping them up in direct collisions, or c) holding them in sweeping them up in direct collisions, or c) holding them in stable orbits stable orbits

Dynamical effect presents a feature of clear Dynamical effect presents a feature of clear distinction between planets and other bodiesdistinction between planets and other bodies

Another way of stating the definition: a Another way of stating the definition: a body in the solar system that is more body in the solar system that is more massive than the total mass of all of the massive than the total mass of all of the other bodies in a similar orbit.other bodies in a similar orbit.

Proxy is µ= M(planet)/M(objects)Proxy is µ= M(planet)/M(objects)

Earth is a pretty big rocky planet....

but not very big as planets go...

• Planets: an object that orbits a star, is large enough to have settled into an object that orbits a star, is large enough to have settled into a round shape and dominates its orbital zonea round shape and dominates its orbital zone;

• Stars: massive gaseous body in outer space, just like the Sun.Unlike a planet, a star generates energy through nuclear fusionand emits visible light;

Objects in a Visible UniverseObjects in a Visible Universe

The Universe is defined as the summation of all particles and energy that exist and the space-time in/during which all events occur.

Stars are in a dynamic balance between gravity and pressure

A sample of starsstars are point sourcescross-like spikes in image (diffraction spikes)caused by strong + concentrated light

stars~ 109m

Super Nova: explosion of the star

One of the most energetic explosive events known is a supernova. These occur at the end of a star's lifetime, when its nuclear fuel is exhausted and it is no longer supported by the release of nuclear energy.

and tiny compared to ordinary stars,

even smaller when compared to giant stars,

and invisible compared to supergiants

• Planets: large celestial bodies in the solarsystem that revolve around the sun and shine by reflected light;

Objects in a Visible UniverseObjects in a Visible Universe

The Universe is defined as the summation of all particles and energy that exist and the space-time in/during which all events occur.

planets~ 107m

Planet sizes are to scale, but distance is not

http://www.youtube.com/watch?v=HEheh1BH34Q

• Planets: an object that orbits a star, is large enough to have settled into an object that orbits a star, is large enough to have settled into a round shape and dominates its orbital zonea round shape and dominates its orbital zone;

• Stars: massive gaseous body in outer space, just like the Sun.Unlike a planet, a star generates energy through nuclear fusion and therefore emits light;

Objects in a Visible UniverseObjects in a Visible Universe

The Universe is defined as the summation of all particles and energy that exist and the space-time in/during which all events occur.

http://janus.astro.umd.edu/SolarSystems/

• Planets: an object that orbits a star, is large enough to have settled into an object that orbits a star, is large enough to have settled into a round shape and dominates its orbital zonea round shape and dominates its orbital zone;

• Stars: massive gaseous body in outer space, just like the Sun.Unlike a planet, a star generates energy through nuclear fusion and therefore emits light;

• Galaxies: a large aggregate of stars (as well as othermaterials such as gas, dust, and dark matter), held in association by their mutual gravity, and relatively isolated from other such aggregates. Usually grouped into three main types: Spiral, Elliptical, and Irregular.

Objects in a Visible UniverseObjects in a Visible Universe

The Universe is defined as the summation of all particles and energy that exist and the space-time in/during which all events occur.

http://janus.astro.umd.edu/SolarSystems/

http://www.seasky.org/celestial-objects/stars.html

A sample of galaxies

Spiral galaxylike our galaxy the Milky Way....

galaxies~ 1021m

A sample of galaxies

speeding toward us at 500,000 km/sec!will arrive in 4 billion years!

Andromeda

A sample of galaxies

Elliptical galaxy Irregular galaxy

we are here

Group Activity

our cosmic address

The Hubble Ultra Deep Field

Describe what you see. What are some of the interesting features?

The Hubble Ultra Deep Field

Look at the objects

Think about the time it took for “info” to arrive

Think about their colors; What can you tell about their temperature?

The Hubble Ultra Deep Field

Look at the objects

Think about the time it took for “info” to arrive

Think about their colors; What can you tell about their temperature?

Which way did the Hubble Space Telescope point when taking the Hubble Ultra Deep Field?

Estimate how many galaxies are in this image.

The Hubble Ultra Deep Field

How many galaxies are there in the visible Universe?

How can we use this image to figure out the number of galaxies in the Universe?

The Hubble Ultra Deep Field

Assuming there are 100 billion galaxies in the visible universe, what fraction of the sky is covered by the HUDF image?

The Hubble Ultra Deep Field

How many planets are there in the visible Universe?

The Hubble Ultra Deep Field

33

Is this really the only planet in the only solar system in the only galaxy that’scomfortable for life?

http://www.youtube.com/watch?v=wJXSSYyIVqw&feature=related

How do you read time in this image?

The Hubble Ultra Deep Field

13.7 billion years in one image

The Hubble Ultra Deep Field

• Planets

• Stars

• Galaxies

Objects in a Visible Universe Objects in a Visible Universe

We are still in mostly “in the dark”…We are still in mostly “in the dark”…

What evidence do we have for dark matter?

What evidence do we have for dark energy?

only ~ 4% ordinary matter !only ~ 4% ordinary matter !

present at ~ 23 %present at ~ 23 %

present at ~ 73 %present at ~ 73 %

http://burro.cwru.edu/JavaLab/GalCrashWeb/main.html

STUDENTS: STUDENTS:

NEXT WEEK PLEASE BRING LAPTOPS (1 OR 2 PER GROUP)

& PRIOR TO COMING TO CLASS, UPLOAD THE FOLLOWING WEBSITE INTO THE “CASH” MEMORY

Light (Electromagnetic Radiation) & Its NatureLight (Electromagnetic Radiation) & Its Nature

Key Concepts for Week-3, Class-2:

(what You need to know, as You will be tested on this material):

Definitions: Planets Stars Galaxies

nuclear fusion reactions within stars