Welcome to AST 2002 H AST 2002 H

  • Slides: 53
Download presentation
Welcome to AST 2002 H

Welcome to AST 2002 H

AST 2002 H General Comments I. Hard class, but also fun. Lots of resources:

AST 2002 H General Comments I. Hard class, but also fun. Lots of resources: a) Attend class b) Keep up with lectures, homework, online resources c) Office hours d) Einstein Club and Preceptors (more on this later) e) SARC tutors and workshops II. Online Resources Mastering Astronomy comes with the e-book, new features for students as well as for instructor. Specific instructions from publisher are on Webcourses. III. Unique aspects of honors section: n Small class atmosphere conducive to discussions n. Can go into more depth on certain subjects IV. Class Mechanics…

AST 2002 H General Comments (Cont. ) IV. Class Mechanics: • Syllabus has all

AST 2002 H General Comments (Cont. ) IV. Class Mechanics: • Syllabus has all the relevant information, READ IT! • The Essential Cosmic Perspective (8 th edition) by Bennett. – Mastering Astronomy comes with the e-book on Webcourses. MAKE SURE you get Mastering Astronomy if you buy the book elsewhere. • 4 Exams: 3 in-class (Thursday February 6, Thursday March 5, and Tuesday April 14), and a cumulative final (on Thursday April 23 at 1: 00 PM) • Grades: 100% exams, plus extra credit (see below)

IV. Class Mechanics: EXTRA CREDIT • Participate in the Einstein Club – To get

IV. Class Mechanics: EXTRA CREDIT • Participate in the Einstein Club – To get extra credit you MUST complete 80% of the assigned homework (you can miss no more than 2). • If at end of semester the homework requirement is fulfilled, extra credit will be earned for several activities: – Homework grades can add as much as 1% to course grade – Meet once a week until April. 14 th with a preceptor (to qualify for this 1% extra credit you cannot miss more than two of these weekly meetings with preceptors). – Attending a workshop at UCF's Student Academic Resource Center (SARC, Phillips Hall Room 113 and VARC) BEFORE Spring Break, can add 1%. – All this can add up to 3% to your course grade!

V. Other: a. Please turn off cell phones, never answer them in class b.

V. Other: a. Please turn off cell phones, never answer them in class b. Do not be shy about asking questions in class, it makes the lecture much more interesting c. Seek help outside class (office hours, preceptor, tutor at SARC/VARC) d. Attendance is very important. Exams will be based on material covered in class. . e. Read chapters BEFORE CLASS, review and study THAT DAY after class f. Not a stargazing class, more like physics of the universe g. Course gets harder: get a good grade on the first exam because its hard to recover later

Unusual Semester! 1. JAXA’s Hayabusa 2 spacecraft is headed back to Earth from asteroid

Unusual Semester! 1. JAXA’s Hayabusa 2 spacecraft is headed back to Earth from asteroid Ryugu: exciting results 2. NASA’s OSIRIS-REx spacecraft is at asteroid Bennu: exciting results We will follow the progress of both sample-return missions during the semester. As a member of the OSIRIS-REx science team, I will have early access to exciting new results. Also, I may have travel to Tucson on short notice. I do not anticipate it, but if that happens I will lecture remotely or find a substitute.

Unusual Semester! 1. JAXA’s Hayabusa 2 spacecraft is headed back to Earth from asteroid

Unusual Semester! 1. JAXA’s Hayabusa 2 spacecraft is headed back to Earth from asteroid Ryugu: exciting results 2. NASA’s OSIRIS-REx spacecraft is at asteroid Bennu: exciting results We will follow the progress of both sample-return missions during the semester. As a member of the OSIRIS-REx science team, I will have early access to exciting new results. Also, I may have travel to Tucson on short notice. I do not anticipate it, but if that happens I will lecture remotely or find a substitute.

Unique Semester! 1. JAXA’s Hayabusa 2 spacecraft is headed back to Earth from asteroid

Unique Semester! 1. JAXA’s Hayabusa 2 spacecraft is headed back to Earth from asteroid Ryugu: exciting results 2. NASA’s OSIRIS-REx spacecraft is at asteroid Bennu: exciting results We will follow the progress of both sample-return missions during the semester. As a member of the OSIRIS-REx science team, I will have early access to exciting new results. Also, I may have travel to Tucson on short notice. I do not anticipate it, but if that happens I will lecture remotely or find a substitute.

Unique Semester! 1. JAXA’s Hayabusa 2 spacecraft is headed back to Earth from asteroid

Unique Semester! 1. JAXA’s Hayabusa 2 spacecraft is headed back to Earth from asteroid Ryugu: exciting results 2. NASA’s OSIRIS-REx spacecraft is at asteroid Bennu: exciting results We will follow the progress of both sample-return missions during the semester. As a member of the OSIRIS-REx science team, I will have early access to exciting new results. Also, I may have travel to Tucson on short notice. I do not anticipate it, but if that happens I will lecture remotely or find a substitute.

Historic Semester! 1. JAXA’s Hayabusa 2 spacecraft is headed back to Earth from asteroid

Historic Semester! 1. JAXA’s Hayabusa 2 spacecraft is headed back to Earth from asteroid Ryugu: exciting results 2. NASA’s OSIRIS-REx spacecraft is at asteroid Bennu: exciting results We will follow the progress of both sample-return missions during the semester. As a member of the OSIRIS-REx science team, I will have early access to exciting new results. Also, I may have travel to Tucson on short notice. I do not anticipate it, but if that happens I will lecture remotely or find a substitute.

Who cares about astronomy anyway?

Who cares about astronomy anyway?

Outline of lecture 1 (Ch 1) 1. 1 Our modern View of the Universe

Outline of lecture 1 (Ch 1) 1. 1 Our modern View of the Universe Survey of the universe and powers of ten 1. 2 The scale (History) of the Universe Astronomical distances 1. 3 Spaceship Earth Motions of Earth, Sun, Galaxies

1. 1 Our Modern View of the Universe Our goals for learning: • What

1. 1 Our Modern View of the Universe Our goals for learning: • What is our place in the universe? • How did we come to be? • How can we know what the universe was like in the past? • Can we see the entire universe?

102

102

Start with Earth-Moon and jump 100 times larger every slide

Start with Earth-Moon and jump 100 times larger every slide

102

102

102

102

102

102

102

102

102

102

102

102

102

102

102

102

DISTANCE SCALES • ASTRONOMICAL UNIT (AU): – The average distance between the Earth and

DISTANCE SCALES • ASTRONOMICAL UNIT (AU): – The average distance between the Earth and the Sun. • About 150 million km or 93 million miles Sun. 1 AU Earth

NOT TO SCALE!!!! KUIPER BELT AND OORT CLOUD PLUTO NEPTUNE URANUS SATURN JUPITER ASTEROID

NOT TO SCALE!!!! KUIPER BELT AND OORT CLOUD PLUTO NEPTUNE URANUS SATURN JUPITER ASTEROID BELT MARS EARTH MERCURY VENUS A TOUR OF THE SOLAR SYSTEM

NOT TO SCALE!!!! 10 20 30 40 URANUS NEPTUNE PLUTO KUIPER BELT AND OORT

NOT TO SCALE!!!! 10 20 30 40 URANUS NEPTUNE PLUTO KUIPER BELT AND OORT CLOUD 5 SATURN . 4. 7 1. 0 1. 5 JUPITER ASTEROID BELT MARS EARTH Distance (AU) MERCURY VENUS A TOUR OF THE SOLAR SYSTEM

DISTANCE SCALES • LIGHT-YEAR (LY): – The distance light can travel in one year.

DISTANCE SCALES • LIGHT-YEAR (LY): – The distance light can travel in one year. • About 9. 5 trillion km – NOTE: this is a distance not a time! – How far is the nearest star?

DISTANCE SCALES • LIGHT-YEAR (LY): – The distance light can travel in one year.

DISTANCE SCALES • LIGHT-YEAR (LY): – The distance light can travel in one year. • About 9. 5 trillion km – NOTE: this is a distance not a time! – How far is the nearest star? 4. 3 Ly

WRITING NUMBERS IN SCIENTIFIC NOTATION CONVENTIONAL SCIENTIFIC NOTATION 341, 000 3. 41 X 105

WRITING NUMBERS IN SCIENTIFIC NOTATION CONVENTIONAL SCIENTIFIC NOTATION 341, 000 3. 41 X 105 0. 0000049 4. 90 X 10 -6 234, 000 2. 34 X 108 0. 0134 1. 34 X 10 -2

1. 1 Our Modern View of the Universe Our goals for learning: • What

1. 1 Our Modern View of the Universe Our goals for learning: • What is our place in the universe? We are on a planet, orbiting a star, in a galaxy (which is a member of the Local Group of galaxies in the Local Supercluster) • How did we come to be? • How can we know what the universe was like in the past? • Can we see the entire universe?

STAR A large, glowing ball of gas that generates heat and light through nuclear

STAR A large, glowing ball of gas that generates heat and light through nuclear fusion

PLANET A moderately large object which orbits a star; it shines by reflected light.

PLANET A moderately large object which orbits a star; it shines by reflected light. Planets may be rocky, icy, or gaseous in composition.

NASA’s Curiosity on Mars PLANET A moderately large object which orbits a star; it

NASA’s Curiosity on Mars PLANET A moderately large object which orbits a star; it shines by reflected light. Planets may be rocky, icy, or gaseous in composition.

PLANET What about Pluto? What about objects similar to Pluto that have been discovered?

PLANET What about Pluto? What about objects similar to Pluto that have been discovered? What about asteroids? The definition of a planet is not so clear (it was much easier for the ancient Greeks…. for them a planet was a star that moved and there were 5 of them)

MOON An object which orbits a planet.

MOON An object which orbits a planet.

ASTEROID A relatively small and rocky object which orbits a star.

ASTEROID A relatively small and rocky object which orbits a star.

COMET A relatively small and icy object which orbits a star.

COMET A relatively small and icy object which orbits a star.

SOLAR (STAR) SYSTEM A star and all the material which orbits it, including its

SOLAR (STAR) SYSTEM A star and all the material which orbits it, including its planets and moons

NEBULA An interstellar cloud of gas and/or dust

NEBULA An interstellar cloud of gas and/or dust

GALAXY A great island of stars in space, all held together by gravity and

GALAXY A great island of stars in space, all held together by gravity and orbiting a common center

THE UNIVERSE The sum total of all matter and energy; that is, everything within

THE UNIVERSE The sum total of all matter and energy; that is, everything within and between all galaxies

AGE OF UNIVERSE Age of Universe: about 14 billion years Age of Solar System:

AGE OF UNIVERSE Age of Universe: about 14 billion years Age of Solar System: about 4. 6 billion years Cosmic Calendar: see details in book

1. 1 Our Modern View of the Universe Our goals for learning: • What

1. 1 Our Modern View of the Universe Our goals for learning: • What is our place in the universe? We are on a planet, orbiting a star, in a galaxy (which is a member of the Local Group of galaxies in the Local Supercluster). • How did we come to be? —The matter in our bodies came from the Big Bang, which produced hydrogen and helium. —All other elements were constructed from H and He in stars and then recycled into new star systems, including our solar system. • How can we know what the universe was like in the past? • Can we see the entire universe?

Where do we come from? • The first (and simplest) atoms were created during

Where do we come from? • The first (and simplest) atoms were created during the Big Bang. • More complex atoms were created in stars. • When the star dies, they are expelled into space…. to form new stars and planets! Most of the atoms in our bodies were created in the core of a star!

SPEED OF LIGHT • The speed of light in the vacuum of space is

SPEED OF LIGHT • The speed of light in the vacuum of space is constant! All light travels the same speed! c = speed of light = 290, 000 m/sec = 2. 9 x 108 m/sec = 290, 000 km/sec

Looking back in time • Light, although fast, travels at a finite speed. •

Looking back in time • Light, although fast, travels at a finite speed. • It takes: – 8 minutes to reach us from the Sun – 8 years to reach us from Sirius (8 light-years away) – 1, 500 years to reach us from the Orion Nebula • The farther out we look into the Universe, the farther back in time we see!

1. 1 Our Modern View of the Universe Our goals for learning: • What

1. 1 Our Modern View of the Universe Our goals for learning: • What is our place in the universe? We are on a planet, orbiting a star, in a galaxy (which is a member of the Local Group of galaxies in the Local Supercluster). • How did we come to be? — The matter in our bodies came from the Big Bang, which produced hydrogen and helium. — All other elements were constructed from H and He in stars and then recycled into new star systems, including our solar system. • How can we know what the universe was like in the past? —When we look to great distances we are seeing events that happened long ago because light travels at a finite speed. • Can we see the entire universe?

1. 1 Our Modern View of the Universe Our goals for learning: • What

1. 1 Our Modern View of the Universe Our goals for learning: • What is our place in the universe? We are on a planet, orbiting a star, in a galaxy (which is a member of the Local Group of galaxies in the Local Supercluster). • How did we come to be? — The matter in our bodies came from the Big Bang, which produced hydrogen and helium. — All other elements were constructed from H and He in stars and then recycled into new star systems, including our solar system. • How can we know what the universe was like in the past? —When we look to great distances we are seeing events that happened long ago because light travels at a finite speed. • Can we see the entire universe? – Nope!

1. 1 Our Modern View of the Universe Our goals for learning: • What

1. 1 Our Modern View of the Universe Our goals for learning: • What is our place in the universe? We are on a planet, orbiting a star, in a galaxy (which is a member of the Local Group of galaxies in the Local Supercluster). • How did we come to be? — The matter in our bodies came from the Big Bang, which produced hydrogen and helium. — All other elements were constructed from H and He in stars and then recycled into new star systems, including our solar system. • How can we know what the universe was like in the past? — When we look to great distances we are seeing events that happened long ago because light travels at a finite speed. • Can we see the entire universe? —No, the observable portion of the universe is about 14 billion light-years in radius because the universe is about 14 billion years old. ALSO (not in Ch. 1 of the book), we can “see” only about 4% of the universe, 96% is made of “dark matter” and “dark energy”.

What have we learned? • How is Earth moving in our solar system? —

What have we learned? • How is Earth moving in our solar system? — It rotates on its axis once a day and orbits the Sun at a distance of 1 AU = 150 million km • How is our solar system moving in the Milky Way Galaxy? — Stars in the Local Neighborhood move randomly relative to one another and orbit the center of the Milky Way in about 230 million years

What have we learned? • How do galaxies move within the universe? — All

What have we learned? • How do galaxies move within the universe? — All galaxies beyond the Local Group are moving away from us with expansion of the universe: the more distant they are, the faster they’re moving • Are we ever sitting still? — No!