music of the spheres - asteroseismology -...

HelasHelas OutreachOutreach

A A deconstructiondeconstruction of of

“Songs“Songs of the of the Stars”Stars”

““Begin at the beginning,”Begin at the beginning,”

the King said, very gravely,the King said, very gravely,

“and then go on “and then go on till you come to the end:till you come to the end:

then stop.”then stop.”

““The beginning”The beginning”

TalkTalkto yourto your

audience audience ––make contactmake contact

Opening your talk Opening your talk -- HumourHumour

Be very careful with jokes!Be very careful with jokes!

AnecdotesAnecdotesTrue storiesTrue storiesSelfSelf--deprecationdeprecation

Podiums are poisonPodiums are poisonLecterns are lethalLecterns are lethal

Do not hide behind the equipment Do not hide behind the equipment ––

no barriers between you and themno barriers between you and them

Get out frontGet out front

Move about Move about somesome

Timing Timing –– the beginningthe beginning

NeverNever trust the equipmenttrust the equipment

Check it out Check it out wellwell beforebefore your talkyour talk

What to do if there are problemsWhat to do if there are problems

Let someone else sort it outLet someone else sort it out

You talk to your audience while things get fixedYou talk to your audience while things get fixedTell a storyTell a storyStart your talkStart your talkIt is a good idea to have backIt is a good idea to have back--up talk that you can up talk that you can give with no presentation materialsgive with no presentation materials

The audience holds you responsibleThe audience holds you responsible

““Going on”: Your presentationGoing on”: Your presentation

The hook!The hook!

The start is where you catch their attentionThe start is where you catch their attention

It is the most important time in your talkIt is the most important time in your talk

Have an idea to hang your talk onHave an idea to hang your talk onYou will come back to that idea at the endYou will come back to that idea at the end

Sir Arthur Stanley Eddington:The Internal Constitution of the Stars

1926

At first sight it would seem At first sight it would seem that the deep interior that the deep interior of the sun and stars of the sun and stars

is less accessible is less accessible to scientific investigation to scientific investigation

than any other region of the than any other region of the universe.universe.

Sir Arthur Eddington(1882 – 1944)

Our telescopes may probe Our telescopes may probe farther and farther farther and farther

into the depths of space; into the depths of space; but how can we ever obtain but how can we ever obtain

certain knowledge certain knowledge of that which is hidden of that which is hidden

behind substantial barriers?behind substantial barriers?

What appliance What appliance can pierce through can pierce through

the outer layers of a star the outer layers of a star and test and test

the conditions within?the conditions within?

Always bring your ideasAlways bring your ideas“down to Earth”“down to Earth”

Relate to everyday lifeRelate to everyday life

Relate to everyday knowledgeRelate to everyday knowledge

This is more difficult with young people because This is more difficult with young people because they have little general knowledgethey have little general knowledge

The Music of the SpheresThe Music of the Spheres

Pythagoras of Samos (c.569 - 475 BC)

2:1 ratio

Plato said that a siren sits on each planet, who carols a Plato said that a siren sits on each planet, who carols a most sweet song, agreeing to the motion of her own most sweet song, agreeing to the motion of her own

particular planet, but harmonising with all the particular planet, but harmonising with all the others.others.

The Music of the SpheresThe Music of the Spheres

Pythagoras of Samos (c.569 - 475 BC)

2:1 ratio

Johannes Kepler (1571 – 1630)

There’s not the smallest orb which thou There’s not the smallest orb which thou beholdestbeholdestbut in his motion like an angel singsbut in his motion like an angel singsStill Still quiringquiring to the youngto the young--eyed eyed cherubimscherubims

(Merchant of Venice, v. 1)(Merchant of Venice, v. 1)

Seeing with soundSeeing with sound

Assume Assume no knowledgeno knowledge

Your audience is intelligentYour audience is intelligent

Some in your audience are highly educatedSome in your audience are highly educated

Some in your audience know more than you do Some in your audience know more than you do about some topics of your talkabout some topics of your talk

Give the basics, but do not talk down to themGive the basics, but do not talk down to them

Sound is a pressure waveSound is a pressure wave

More frequent collisions = faster sound speedMore frequent collisions = faster sound speedHigher temperature = faster sound speedHigher temperature = faster sound speedLighter gases = faster sound speedLighter gases = faster sound speed

The range of human hearingThe range of human hearing

20 Hz to 20,000 Hz20 Hz to 20,000 Hz

Bats echoBats echo--locate at 50,000 Hzlocate at 50,000 Hz

1 cycle per second = 1 Hertz = 1 Hz1 cycle per second = 1 Hertz = 1 Hz


20 Hz to 20,000 Hz20 Hz to 20,000 Hz

Elephants “rumble” at 10 HzElephants “rumble” at 10 Hz

Blue Whales “sing” at 12Blue Whales “sing” at 12--200 Hz 200 Hz

1 cycle per second = 1 Hertz = 1 Hz1 cycle per second = 1 Hertz = 1 Hz

12-200 Hz songs 16-25 Hz buzzes, rasps


20 Hz to 20,000 Hz20 Hz to 20,000 Hz

Galaxies have sound waves with periods Galaxies have sound waves with periods of once per 200 million years!of once per 200 million years!

1D oscillations1D oscillations

Fundamental First overtone Second overtone

nodes

modes

1D oscillations: 1D oscillations: The baseball batThe baseball batThe cricket batThe cricket bat

The “sweet spot”The “sweet spot”

InterferenceInterference

HarmonicsHarmonics

2D oscillation 2D oscillation –– drumsdrumsthe the radialradial modesmodes

2nd-overtone mode1st-overtone modefundamental mode

2D oscillation 2D oscillation –– drumsdrumsthe the nonnon--radialradial modesmodes

first overtonedipole modedipole mode quadrupole mode

2D oscillations 2D oscillations –– drumsdrums

2D oscillations2D oscillations

2D dipole oscillations in the 2D dipole oscillations in the Tacoma Bridge disasterTacoma Bridge disaster

Listening to the songs of the starsListening to the songs of the stars

3D oscillations 3D oscillations –– starsstarsradial modesradial modes

Modes in stars are not harmonicModes in stars are not harmonic

Cepheid variablesCepheid variables

Cepheid Horn by Zoltan Kollath, Konkoly Observatory, Budapest

Cute animationsCute animations

Scientific animations are Scientific animations are helpfulhelpful

Irrelevant animations Irrelevant animations distract your audiencedistract your audience

Cepheid variablesCepheid variables

Cepheid Horn by Zoltan Kollath, Konkoly Observatory, Budapest

Cepheid variablesCepheid variablesHenrietta Leavitt (1868Henrietta Leavitt (1868--1921)1921)Discovered in 1908 theDiscovered in 1908 the

PeriodPeriod--LuminosityLuminosityrelation for Cepheids in the LMCrelation for Cepheids in the LMC

“It is worthy of notice that … the brighter variables have the longer periods.” (Leavitt 1908)

Henrietta Leavitt’s PL discoveryHenrietta Leavitt’s PL discovery19121912

brighter

mag

nit

ud

e

Period in days

The proof that “spiral nebulae”The proof that “spiral nebulae”are galaxies are galaxies -- 19231923

A Cepheid in AndromedaEdwin Hubble

Doppler shiftDoppler shift

Doppler shift Doppler shift –– shock wavesshock waves

Using Doppler Shift to measure velocityUsing Doppler Shift to measure velocity

Using Doppler Shift to Using Doppler Shift to measure velocitymeasure velocity

Expansion of the UniverseExpansion of the Universe

Fainter (so farther)

10000 km/s

1000 km/s

Edwin Hubble and Milton Humason, 1931, Astrophysical Journal, Edwin Hubble and Milton Humason, 1931, Astrophysical Journal, 7474, 43, 43

3D in stars3D in stars

Radial modes


Non-radial modes: The dipole mode

l=1, m=0

HR 3831 HR 3831 –– IM VelorumIM Velorum

The oblique pulsation of HR 3831

The sunThe sun

••TRACE 171A pass band; 1 MK plasma; 1999 November 6TRACE 171A pass band; 1 MK plasma; 1999 November 6

How does asteroseismology work?How does asteroseismology work?


Non-radial modes: quadrupole modes

l=2, m=2l=2, m=0

Rotation of the sunRotation of the sun

Globular cluster M4Globular cluster M4

BPM 37093 “Bruce”

roAp stars - HR 1217

dipole(-like)

like nothing youhave ever seen

new mode

strange doublet

HR 1217

Radial VelocityRadial Velocity

Bouchy, F., et al. 2005, A&A, 440, 609

GroundGround--based detections of stellar oscillationsbased detections of stellar oscillations

Sun (BiSON)

GroundGround--based detections of stellar oscillationsbased detections of stellar oscillations

Bedding, T., et al. 2004, ApJ, 614, 380

α Centauriα Cen A

The Red Giant Star The Red Giant Star ξξ HydraeHydrae

LCSEUniv.

Minnesota

ξ ξ HydraeHydrae

RR Lyrae stars in the RR Lyrae stars in the globular cluster M3globular cluster M3

Zoltan Kollath – Konkoly Observatory, Budapest

What appliance What appliance can pierce through can pierce through

the outer layers of a star the outer layers of a star and test and test

the conditions within?the conditions within?

Stellarmusicno1Stellar acoustics as input for music compositionStellar acoustics as input for music composition

ZoltánZoltán KolláthKolláthKonkolyKonkoly Observatory, Budapest, HungaryObservatory, Budapest, Hungary

JenőJenő KeulerKeulerInstitute for Musicology, Budapest, HungaryInstitute for Musicology, Budapest, Hungary

http://www.konkoly.hu/staff/kollath/stellarmusic/

Some detailsSome details

Think about your audienceThink about your audience

Can they read your slides?Can they read your slides?Have you left them enough time?Have you left them enough time?Have you put too much in?Have you put too much in?Do they understand your graphs?Do they understand your graphs?

Keep you eye on them to see how they are Keep you eye on them to see how they are responding to you!responding to you!

Bad! GraphsGraphs

GraphsGraphsgood

Can they read your slides?Can they read your slides?If not, describe themIf not, describe them

If you do not want them to read it,If you do not want them to read it,

then do not put it in!then do not put it in!

Be careful of too much detailBe careful of too much detail

Words on slidesWords on slides

Notes for you?Notes for you?

Notes for them?Notes for them?

Both! Both! ––but mostly for thembut mostly for them

Make sure they are usefulMake sure they are useful

Can they hear you?Can they hear you?

A microphone is your friendA microphone is your friend

Do not be frightened of itDo not be frightened of it

It does not bite!It does not bite!

Listen to yourself Listen to yourself ––how do you sound to them?how do you sound to them?

““and then go on and then go on till you come to the end”till you come to the end”

Remember:Remember:

You are telling a storyYou are telling a story

Make sure there are interesting pointsMake sure there are interesting pointsto stitch together the detailsto stitch together the details

Make sure there is something for everyone Make sure there is something for everyone ––put in some advanced ideas, tooput in some advanced ideas, too

Managing your timeManaging your time

Have more than one endingHave more than one ending

Put less on slidesPut less on slidesYou can adjust how much you sayYou can adjust how much you sayYou cannot adjust the slidesYou cannot adjust the slides

Be aware of the timeBe aware of the time

Going overtimeGoing overtime

Do not do it! Do not do it! –– It is a sinIt is a sin

Your audience will stop listening to youYour audience will stop listening to you

Everyone has plans following your talkEveryone has plans following your talk

A polished presentationA polished presentation

Does it matter?Does it matter?

Yes! Yes!

It says that you have taken a lot of time because It says that you have taken a lot of time because thisthisaudience is audience is importantimportant

Audiences appreciate thatAudiences appreciate that

Don’t point out small faultsDon’t point out small faultsin your talkin your talk

Your audience will not usually notice Your audience will not usually notice

Do not bring faults to their attentionDo not bring faults to their attention

Prepare:Prepare:butbut

Do not apologise for not preparingDo not apologise for not preparing

Disaster strikesDisaster strikes

What to do?What to do?

Talk to your audience!Talk to your audience!

Question timeQuestion time

NeverNever attack a member of the audience!attack a member of the audience!

You will threaten them allYou will threaten them all

Be calm Be calm Be reasonableBe reasonable

Be patient for the first few questionsBe patient for the first few questions

HecklersHecklers

The “form” of your storyThe “form” of your storyTypical science talk

Novel or play

““Begin at the beginning,”Begin at the beginning,”

the King said, very gravely,the King said, very gravely,

“and then go on “and then go on till you come to the end:till you come to the end:

then stop.”then stop.”

music of the spheres - asteroseismology -...

Documents