{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Lecture 2 - Exploring the Heavens

Lecture 2 - Exploring the Heavens - Exploring the Heavens...

Info icon This preview shows pages 1–9. Sign up to view the full content.

View Full Document Right Arrow Icon
Exploring the Heavens ASTRONOMY 3 Lesson 2 1 Star Trails above Mauna Kea - see http://antwrp.gsfc.nasa.gov/apod/ap051220.html
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
NATURE of the Universe Review of Lesson 1 Astronomy - Exploring the Heavens • Location of Sunrise and Sunset on the horizon changes with season • Constellations are different in different cultures. They help people to orient themselves on the sky and to use them for navigation. • Powers of 10: the observable Universe is vast, 10 19 times larger than Earth, 10 26 times larger than a Human 2
Image of page 2
• E.1 The “Obvious” View • E.2 Earth’s Orbital Motion • E.3 The Motion of the Moon • Summary & Homework NATURE of the Universe Today’s Topics Astronomy - Exploring the Heavens Lab 2 (starts this week): Planetarium and Sky Motions 3
Image of page 3

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
NATURE of the Universe The “Obvious” View Astronomy - Exploring the Heavens Stars appear to be projected on the “celestial sphere”, while in reality each star might be at a different distance from Earth Constellations do not represent physical groups of stars! 4 The speed of light is 3*10 8 m/s. In a year light travels 1*10 16 m. This distance is called a lightyear. To cross the Milky Way, which is 10 21 m or 10 5 lightyears in diameter, light needs 10 5 yr.
Image of page 4
NATURE of the Universe The “Obvious” View Astronomy - Exploring the Heavens Mapping the skies - how to find your way among the stars? 5 Coordinates of the Math Sciences Building: longitude W 118° 26’ 35’’, latitude N 34° 4’ 11’’
Image of page 5

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
NATURE of the Universe The “Obvious” View Astronomy - Exploring the Heavens Mapping the skies - how to find your way among the stars? On Earth, latitude and longitude are used identify a location on Earth (e.g. with the help of GPS, the Global Positioning System) 5 Coordinates of the Math Sciences Building: longitude W 118° 26’ 35’’, latitude N 34° 4’ 11’’
Image of page 6
NATURE of the Universe The “Obvious” View Astronomy - Exploring the Heavens Astronomers place a grid of coordinates across the celestial sphere to locate stars in a particular region of the sky. Mapping the skies - how to find your way among the stars 6
Image of page 7

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
NATURE of the Universe The “Obvious” View Astronomy - Exploring the Heavens We call these coordinates “Right Ascension ” and “Declination • Right ascension : measured in hours, minutes and seconds eastward from the position of the Sun at the spring equinox • Declination : degrees north (positive) or south (negative) of the celestial equator Examples: Polaris (Epoch J2000) RA = 2 h 31 m 49 s DEC= +89° 15’ 51’’ Rigel, β Orionis (J2000) RA = 5 h 14 m 32 s DEC= -8° 12’ 6’’ 7 On a sky chart with North facing up, East is always to the Left - this is opposite to a terrestrial map, where East is to the right. Imagine lying on your back watching the sky with your head facing north - east will then we to your left!
Image of page 8
Image of page 9
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern