New Core Curriculum week 3, class-2 Foundations of Scientific Process Visible Objects in the Universe

The Hubble Ultra Deep Field

Hubble Space Telescope 2.4m optical telescope resides in orbit of Earth

The Hubble Ultra Deep Field What objects do we see here?

an object that orbits a star, is large enough to have settled into a round shape and dominates its orbital zone Planets: an object that orbits a star, is large enough to have settled into a round shape and dominates its orbital zone; Objects 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? Conventional (past) definition: Planet is a body that orbits a star, shines by reflecting the star’s light and is larger than an asteroid. What observation ignited the debate about the definition of a planet?  Observation of the vast population of objects in the vicinity of Pluto (Kuiper Belt Objects = KBO);  In particular, KBO Eris is larger than Pluto;  If Pluto is a planet, not only Eris but also dozen of other KBO objects will need to be considered a planet.

Key Feature: Planet is a body massive enough to dominate its orbital zone by a) flinging smaller bodies away, b) sweeping them up in direct collisions, or c) holding them in stable orbits Dynamical effect presents a feature of clear distinction between planets and other bodies Another way of stating the definition: a body in the solar system that is more massive than the total mass of all of the other bodies in a similar orbit. Proxy is µ= M(planet)/M(objects)

Earth is a pretty big rocky planet....

but not very big as planets go...

an object that orbits a star, is large enough to have settled into a round shape and dominates its orbital zone Planets: an object that orbits a star, is large enough to have settled into a 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 emits visible light; Objects 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 stars stars are point sources cross-like spikes in image (diffraction spikes) caused by strong + concentrated light stars ~ 10 9 m

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 solar system that revolve around the sun and shine by reflected light; Objects 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 ~ 10 7 m Planet sizes are to scale, but distance is not

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

an object that orbits a star, is large enough to have settled into a round shape and dominates its orbital zone Planets: an object that orbits a star, is large enough to have settled into a 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 other materials 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 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.

A sample of galaxies Spiral galaxy like our galaxy the Milky Way.... galaxies ~ m

A sample of galaxies speeding toward us at 500,000 km/sec! will arrive in 4 billion years! Andromeda

A sample of galaxies Elliptical galaxyIrregular 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’s comfortable for life?

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 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 ! present at ~ 23 % present at ~ 73 %

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 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