INTRODUCTION - Highland Township · Death by Black Hole and other Cosmic Quandaries – Neil...

Post on 20-May-2020

8 views 0 download

Transcript of INTRODUCTION - Highland Township · Death by Black Hole and other Cosmic Quandaries – Neil...

INTRODUCTION● Lawrence Halstead ● Email: lt_halstead25@comcast.net ● Cell: 810-449-1357

ASTRONOMY BASICS● Planets, stars, galaxies – an issue of scale● Most celestial objects can be found by locating two

roughly flat, circular planes● Ecliptic plane (Solar System)● Galactic plane (Milky Way)

● Distances are usually measured in light years● 1 light year = distance light travels in 1 year● Speed of light = 186,000 miles / second● 1 light year = a little less than 6 trillion miles

Plane #1 : The Ecliptic Plane

The Solar System

The Ecliptic Plane

THE ECLIPTIC PLANE

moon

venus

saturn

mars

sun

THE ECLIPTIC PLANE

This is where you can see the Sun, the Moon and all the planets

Views from the Ecliptic Plane

Al Bates - FAAC

Mercury

NASA

Venus

NASA / JPL

The Moon

LICK OBSERVATORY

NASA

Mars (+2 moons)

NASA / JPLNASA / USGS

Jupiter (+67 moons)

NASA / CASSINI

Saturn (+62 moons)

NASA / JPL / CASSINI / ESA

Uranus (+27 moons)

NASA/ESA/STSClESO

Neptune (+14 moons)

15NASA / VOYAGERNASA / JPL

Pluto (+5 moons)

NASA-JHUAPL-SWRI -

Dwarf Planets

17

LEXICON

Kuiper Belt (out to about .001 LY)

18

ASA/ESA/G. Bacon

WilyD on English Wikipedia

Oort Cloud (out to about 0.7 LY away)

19NASA

w/ User / Mkfairdpm

The Planets and the Sun

Most stars are smaller than the Sun….

But most stars that we can see are larger than the Sun.

Our Sun to AntaresRigel is 50,000 times more luminous than the Sun.

Sun/Ecliptic

Plane #2:

THE MILKY WAY GALAXY (artist’s concept, not a photo) – 80,000 light years across

The ecliptic plane and the Milky Way galaxy

THE MILKY WAY GALAXY as seen from within

This is where you can find nebulae and star clusters in abundance

Kerry-Ann Lecky Hepburn - http://www.weatherandsky.com/

THE MILKY WAY GALAXY – The big picture

Views from the Galactic Plane

Kerry-Ann Lecky Hepburn - http://www.weatherandsky.com/

Beyond Plane #2: Andromeda Galaxy (M31) – 2.3 million light years away

Views from beyond the Galactic Plane

Kerry-Ann Lecky Hepburn - http://www.weatherandsky.com/

Virgo Galaxy Cluster – 60 million light years away

As far as we can see (Hubble Deep Field) – about 10 billion light years

Astronomy BasicsSummary● Celestial objects appear to rise and set in roughly circular

paths.● The sun is a larger than average star about halfway out

along a small spiral arm of the Milky Way Galaxy.● The positions of various celestial objects are predictable.● Once you know where to look, it all makes sense.

● Sun, Moon, and planets in the ecliptic plane.● Star clusters and nebulae in the galactic plane.● Galaxies above or below the galactic plane.

● The scales are daunting.

A telescope is a light bucket

REU program, N.A.Sharp/NOAO/AURA/NSF

Different types of scopes

REFRACTOR

REFLECTOR

SCHMIDT-CASSEGRAIN

Messer Woland

Setting up the rental scopes

34

Finder

Main eyepiece

Do not touch knobs on back of the scopeFocus knob

Setting up your finder

Al Bates - FAAC

EYEPIECE FINDER - ADJUSTFINDER

EYEPIECEFINDER

Turn on the red dot finder

36

Turn this dial CW (click) to turn on the red dot. Turn it farther to make it brighter.

Look through here to see the red dot.

Align the red dot finder

37

Turn this knob to move the red dot from side to side

Turn this knob to move the red dot up and down

Tonight’s targets:

38

● The Moon ● Jupiter ● Saturn ● Mars ● ISS (10:02 PM for 3 minutes) ● Albireo ● Hercules Cluster ● Ring Nebula

Why do constellations change during the year?

Spring Virgo, Leo

Summer Sagittarius, Scorpius

Fall Pegasus, Pisces

Winter Orion, Gemini

Summer guidepostslooking high toward southeast

SCORPIUS

AQUILA

LYRA

HERCULES

CYGNUS

SAGITTARIUS

THE SUMMER TRIANGLE OF BRIGHT STARS: DENEB IN CYGNUS, VEGA IN LYRA, ALTAIR IN AQUILA

CYGNUS THE SWAN FLIES ALONG THE SUMMER MILKY WAY TOWARD THE GALACTIC CENTER. .

THE CENTER OF THE MILKY WAY GALAXY LOOKS LIKE STEAM RISING FROM THE TEAPOT OF SAGITTARIUS.

ECLIPTIC PLANE

GALACTIC PLANE

HERCULES IS A TRAPEZOID LYING 1/3 OF THE WAY FROM VEGA TO ARCTURUS.

Moon’s path Milky Way

Looking Southwest mid-summer to early fall 2016

Horizon

Looking southeast high overhead mid-summer to early fall

Milky Way The “Northern Cross”

Hercules Star Cluster

Albireo: Blue and Gold Double Star

Seeing the ISS● Go to NASA Human Space Flight

Tracking website: ● http://spaceflight.nasa.gov/realdata/tracking/

● Click “sighting opportunities” ● Input your location ● Find sighting times and

directions. ● Remember that satellites

generally fly west to east.

Mike Tyrell – astrospider.com

Neutron Stars● Massive star undergoes

supernova. ● Remnants collapse into highly

dense core. ● 1 tsp of material would weigh about

12,000,000,000,000 lbf on Earth. ● As electron capture occurs, protons

become neutrons. ● As collapse occurs, spin becomes

very rapid. ● May appear to us as a pulsar.

NASA/ESA/Hubble

Black Holes● If the initial star is sufficiently

massive, the collapse does not stop at the neutron level.

● The core collapses to a singularity.

● Such a severe distortion in space and time that light cannot escape - i.e. escape velocity is greater than c.

● Space and time effectively face a threshold at the event horizon.

● Millions – or billions of solar masses

● Occur at the center of most galaxies.

● Ingest matter in a disk shape and eject what escapes in polar jets.

Supermassive Black Holes

NASA/JPL/CalTech

The Supermassive Black Hole in Our Galaxy

Supermassive Black Holes● Most are fairly “quiet.” ● When they become active, the gas

/ dust / stars streaming into the hole become very hot and very bright.

● When they become active, the jets become very hot and very bright.

Ker

ry-A

nn L

ecky

Hep

burn

- ht

tp:/

/w

ww

.wea

ther

ands

ky.co

m/

NA

SA

/ES

A/H

ubbl

e

QUIET

ACTIVE

Quasars

● Originally thought to be very energetic, nearby stars. ● Found to be beyond – way beyond – the reaches of our

galaxy. ● This meant that these objects were as bright as entire

galaxies, but very small and very far away. ● More numerous at great distances – i.e. very long ago. ● Now thought to be galaxies in the process of formation,

with active black holes gathering mass and producing enormous energy.

NASA/ESA/Hubble

Gravitational Lensing

● Extreme gravity around massive objects distorts space and time.

● This can cause light to bend as it follows the curvature of spacetime.

● Such a phenomenon can act like a lens.

NASA/ESA/Hubble

Gravitational Waves● Detected in September 2015 at two locations almost

simultaneously. ● These two instruments measured tiny (1/1000 the

size of a proton) distortions in spacetime by measuring the stretching of the Earth as the waves pass through it.

● The results matched Einstein’s predictions precisely for the merging of two medium sized black holes at ~ 1/2 c about 1.3 billion years ago.

● The energy difference between the merging black holes and the final black hole was 3 solar masses!!

● If gravitons were involved, they were limited to less than 10 e - 55 kg 51

Recommended Reading● Nightwatch – Terence Dickinson – (Firefly) – Absolutely the best

source book for beginners.● Astronomy Hacks – Robert Bruce Thompson and Barbara

Fritchman Thompson – (O’Reilly) – Great tips for observing, describes what is generally learned only by experience.

● The Universe from your Backyard – David J. Eicher – (Astromedia) – Excellent reference for amateur observers.

● Death by Black Hole and other Cosmic Quandaries – Neil DeGrasse Tyson – (Norton) – Interesting description of current state of the art.

● Burnham’s Celestial Handbook Volumes 1 – 3 – Robert Burnham Jr. – (Dover) In depth reference, includes fascinating details, technical.

● Bad Astronomy – Philip Plait – (Wiley) – funny and accurate description of astronomy hoaxes and the arguments against them.

● Cosmos – Carl Sagan – (Random House) – still one of the best books on the subject, slightly outdated.

Picture Credits● Celestron ● Robert Nemiroff and JerryBonnell – Astronomy Picture of the Day● Jerry Lodriguss - http://www.astropix.com/● Kerry-Ann Lecky Hepburn - http://www.weatherandsky.com/● Guillaume Dargaud - http://www.gdargaud.net● Mike Tyrell – astrospider.com● National Optical Astronomy Observatory/Association of Universities for

Research in Astronomy/National Science Foundation ● REU program, N.A.Sharp/NOAO/AURA/NSF● NASA, ESO, JPL● Messer Woland – Creative Commons Attribution Share Alike 2.5● David Snyder - University Low Brow Astronomers● Al Bates - Ford Amateur Astronomy Club● Greg Burnett – Ford Amateur Astronomy Club● Paul Walkowski - University Low Brow Astronomers

Summer scope targets

THE CYGNUS REGION IS ONE OF THE RICHEST STAR FIELDS IN THE MILKY WAY. THOUSANDS OF STARS CAN BE SEEN IN BINOCULARS

ALBIREO – BEAUTIFUL BLUE AND GOLD DOUBLE STAR

M57 RING NEBULA – REMAINS OF A DYING STAR LOOKS LIKE A DONUT 1400 LY

M92 GLOBULAR CLUSTER SLIGHTLY SMALLER THAN M13 26 KLY

M13 – STUNNING GLOBULAR CLUSTER ROUGHLY ½ MILLION STARS IN ONE SPHERICAL GROUP 21KLY DENEB 1600 LY

VEGA 25 LY

HERCULESCYGNUS

LYRA

More summer scope targets

THE REGION SURROUNDING THE MILKY WAY GALACTIC CENTER IS PACKED WITH MILLIONS OF STARS AND HUNDREDS OF STAR CLUSTERS.

M17 SWAN NEBULA BRIGHT 6 KLY

M11 WILD DUCK CLUSTER 6 KLY

M22 GLOBULAR CLUSTER BRIGHT 10 KLY

M8 LAGOON NEBULA BRIGHT 4 KLY

M20 TRIFID NEBULA 5 KLY

JEWEL BOX CLUSTER

M4 GLOBULAR CLUSTER 14 KLY

ANTARES – RED SUPERGIANT STAR 600 LY

ALTAIR 17 LY

AQUILA

SAGITTARIUS

SCORPIUS

OPHIUCHUS