Starry Monday at Otterbein

Astronomy Lecture Series-every first Monday of the month-

November 5, 2007

Dr. Uwe Trittmann

Welcome to

Today’s Topics

• Recent Advances in Astronomy - Introduction

• The Night Sky in November

Feedback!

• Please write down suggestions/your interests on the note pads provided

• If you would like to hear from us, please leave your email / address

• To learn more about astronomy and physics at Otterbein, please visit– http://www.otterbein.edu/dept/PHYS/weitkamp.asp

(Obs.)

– http://www.otterbein.edu/dept/PHYS/ (Physics Dept.)

Recent Advances in Astronomy

• Data

• Theory

• Instruments

• Space Flight

• Space probes

Introduction• In the last 15 years cosmology has become a (very) exact science

– 1970ies: Age of the universe is 10-20 billion yrs– Now: the universe is 13.7±0.1 billion years old

• Eagerly anticipated results have been obtained– “Temperature” of the universe is 2.725 K, isotropic 1 part in 100,000

• Unexpected discoveries occurred– Acceleration of cosmological expansion– The universe contains strange & unknown stuff

• Changing of space exploration agencies – Commercial spaceflight – China, Japan, India– Bush’s Moon-Mars initiative changes NASA’s objectives

• Instrumentation has improved dramatically– CCD cameras– Adaptive optics

• New “Astronomies”– Neutrino, X-ray, IR, ...

Recent Advances in Astronomy: Space Probes

• Cassini / Huygens• Chandra• Mars Rovers• WMAP• Galileo• Hayabusa• Deep Impact• Many more …

Deep Impact – The Comet

Crasher

Comet Impact: July 4, 2005

Impact Velocity: 23,000 mph

Spacecraft Size:Flyby spacecraft - nearly as large as a Volkswagen Beetle automobile.

Impactor spacecraft - about the same dimensions as a typical living room coffee table.

Comets - Traveling Dirty Snowballs• Small icy bodies, “dirty snowballs”

• Develops a “tail” as it approaches the Sun

Comet Anatomy

• Tail may be up to 1 A.U. long

Halley’s Comet – Now and then

• Halley’s Comet in 1910• Top: May 10, 30° tail

• Bottom May 12, 40° tail • Halley’s Comet in 1986• March 14, 1986

Comet Shoemaker-Levy 9

• HST image (1994); Earth added to show scale

Comet Shoemaker-Levy 9

Headed for Jupiter…

Impact on Jupiter

Deep Impact – The Comet

Crasher

Comet Impact: July 4, 2005

Impact Velocity: 23,000 mph

Spacecraft Size:Flyby spacecraft - nearly as large as a Volkswagen Beetle automobile.

Impactor spacecraft - about the same dimensions as a typical living room coffee table.

Temple 1 Coordinate System

“Deep Impact” crashes into comet

Temple 1

This is how a comet looks like!

Viewed from the flyby spacecraft

from Hubble Space Telescope

• Spirit at Gusev Crater– Sol: 1365 Time: 21:18– Sols past warranty: 1275

• Opportunity at Meridiani Sinus– Sol: 1345 Time: 9:17– Sols past warranty: 1255

Martian Surface Iron gives the characteristic Mars color: rusty red!

View of Viking 1 1 m rock Sojourner

Martian Panorama

Note: the sky is not black as on the moon,

but pale pink of the dust in the atmosphere!

“Twin Peaks” – about 1-2 km away

Mars Panorama: Opportunity has landed!

Landing Sites

A couple of 1000 miles apart!

Meteorite ALH 84001

• Discovered in Antarctica in 1984– 2 kg, 17 cm across

• Chemical analysis indicates it came from Mars

• In 1996, a team of scientists argued that it contains fossilized evidence of bacteria that came from Mars

Cassini/ Huygens

• Spectacular data from Saturn, Titan, and the Rings

Titan• Titan is the only moon in the solar system

known to have an atmosphere

Infrared picture shows surface details

Titan from Cassini

Haze and Atmosphere

Methane Clouds

False Colored Image

Map of Titan

Methane Rain & Lakes

Huygens sees Shoreline descending

SOHO• The Solar and

Heliospheric Observatory (SOHO) monitors the Sun (launched 1995). It provides crucial early warnings of impending space weather that can destroy satellites and knock out power grids. Scientists credit SOHO with allowing forecasts that prevent damage and losses that might otherwise occur.

Erupting prominence

Hubble Space Telescope

• Launched 1993

• Above the atmosphere

• 2.4m Mirror

HST: Planets

Hubble Ultra Deep Field

HST: M51 Spiral Galaxy

The Night Sky in November

• The sun is past autumn equinox -> longer nights!

• Autumn constellations are coming up: Cassiopeia, Pegasus, Perseus, Andromeda, Pisces

lots of open star clusters!

• Mars is visible later at night

Moon Phases• Today (Waning Crescent)

• 11/ 9 (New Moon)

• 11 / 17 (First Quarter Moon)

• 11 / 24 (Full Moon)

• (Last Quarter Moon)

Today at

Noon

• Sun at meridian, i.e. exactly south

10 PM

Typical observing hour, early October

• Mars

• Uranus

• Neptune

Star Maps

Celestial North Pole – everything turns around this point

Zenith – the point right above you & the middle of the map

40º

90º

West

The summer triangle lingers on …

Due North

• Big Dipper points to the north pole

High up – the Autumn

Constellations

• W of Cassiopeia

• Big Square of Pegasus

• Andromeda Galaxy

Andromeda Galaxy

• “PR” Foto

• Actual look

South-East

Perseus,

Auriga & Taurus

with Plejades and the Double Cluster

South-West – 2006

• Planets– Uranus– Neptune

• Zodiac:– Capricorn

– Aquarius

South-West –2007

• Planets– Uranus– Neptune

• Zodiac:– Capricorn

– Aquarius

Mark your Calendars!

• Next Starry Monday: February 4, 2008, 7 pm (this is a

Monday )

• Observing at Prairie Oaks Metro Park: – Friday, November 16, 6:30 pm– Friday, January 11, 6:00 pm– Friday, February 15, 6:30 pm

• Web pages:– http://www.otterbein.edu/dept/PHYS/weitkamp.asp (Obs.)– http://www.otterbein.edu/dept/PHYS/ (Physics Dept.)

Mark your Calendars II

• Physics Coffee is every Wednesday, 3:30 pm

• Open to the public, everyone welcome!

• Location: across the hall, Science 256

• Free coffee, cookies, etc.