2016NoCoAstro

POLARITY REVERSAL SIMULATION | SCIENCENEWS Magnetic field lines (top) result from convecting liquid iron (bottom) April NoCoAstro Questions, comments, submissions, photos or just to say ‘hello’: How much do you really know about the pale blue dot? ObjView ObjView at NoCoAstro dot org OUR JOURNEY CONTACT Amanda Bell EDITOR

April ), 9pm 9pm ), ), 8:45pm ), , 8:30pm , , 8:30pm , pre-register parkreq’d fee Carter( Lake Poudre Learning Center Poudre Reservoir Creek Fossil ( Ridge Bobcat Speaker: TBD Speaker: Date: Thursday, May 5th, 6:15-7:45pm 5th, May Thursday, Date: NOCOASTRO MEETING NOCOASTRO OUTREACH Join us for our monthly awesomely-nerdy astro talk: astro awesomely-nerdy ourmonthly for Joinus Just stop by the Fort Collins Museum of Discovery. Discovery. oftheFort Museum Collins by stop Just

knowledge, please contact Bob: VP at NoCoAstro dot org. dot NoCoAstro at VP Bob: contact please knowledge, 11th, Wednesday 11th, Friday 13th, Friday 27th, Saturday 28th,

DID YOU KNOW…? All meetings are FREE & open to the public! toopenthepublic! & FREE meetingsAll are KNOW…? YOU DID MAY astronomical their with club the dazzle to like whowould someone know Ifyou MAY H OME, SWEET EARTH

ORIGIN OF NAME: Our planetary home has been called Earth for at least 1000 years. Did you know that Earth is the only planet that wasn't named after a Greek or Roman god or goddess? ATMOSPHERE TYPE: As you probably remember from elementary school, our atmosphere is primarily oxygen (~20%) and nitrogen (~78%) by volume. Our atmosphere thins with increasing altitude and 3/4 of it is within 6.8 miles (11km) of the surface. You may be saying to yourself, ‘That’s great but where does Earth end & space begin?’ Good question. MOONS: Surely we have one moon, right? Simply put, moons are just natural satellites. So, what about the quasi-orbital satellite called Cruithne (CREW-een-ya)? Maybe we have a mini moon or does Earth just have temporary moons periodically? SIZE: If size matters, Earth is the winner! It isn’t just the largest terrestrial planet in our solar system but also the most dense. EQUATORIAL CIRCUMFERENCE: 24,873.6 miles [moon is 27% the size of Earth]. VOLUME: 260 billion cubic miles [moon is 2% Earth volume]. MASS: 5.97 * 10^24 kg [moon is 1.2% the mass of Earth]. Fun Fact: MEAN DENSITY: 5.513 g/cm cubed [most dense in the solar system]. Lunar libration is why even UNCOMPRESSED DENSITY: 4.4 g/cm cubed. [By comparison, the moon has the weakest though only 50% of the gravity and smallest mass, so is the least dense of the 5 terrestrial worlds, including Mercury, moon is visible at once, we Venus, Earth and Mars.] This measurement is the average density if the planetary materials actually see 59% of its were at zero pressure. Higher uncompressed density indicates greater metal content. Do you surface from Earth know why densities decrease for the planets as we move outward from the sun? MAGNETIC FIELD: Our geomagnetic field, which is constantly changing, extends from Earth’s interior to the place where it meets the solar winds. A paleomagnetic study to find the earliest evidence of magnetic fields has shown it to be present since at least 3,450M years ago. Is a magnetic field a prerequisite for life? April NoCoAstro April ?

Fun Fact: geraniums Ozone is blue and smells like ? How lucky is that is lucky How on Earth; that’s 295.3 295.3 that’s onEarth; -136 deg in 2010 in deg -136 Let Phil Plait explain explain Plait Phil Let in the solar system; planetary system; solar inthe and . ? 159.3 deg in 2005 in deg 159.3 ? We’re on our way (like the slow & steady &steady slow the (like onourway We’re ? How do we characterize terrestrial do we characterize How versus planets Jovian similar to the albedogiants the to ofgas similar . 23.4 degrees [the moon is tilted a mere 6.68 degrees]. The degrees]. 6.68 mere a tilted moonis [the degrees 23.4 Terrestrial. Terrestrial. : : slowing down slowing We have recorded + recorded have We : Without the moon, we could be in real trouble real webe in could Withoutmoon, the About 93M miles, which is also equal to 1 A.U. or ‘astronomical unit’. unit’. ‘astronomical or A.U. 1 to equal also whichis miles, 93M About : Earth’s is albedo : 9.8 m/s squared, which is also the standard ‘one g’ used when measuringused all of gravity surface g’ ‘one standard the also whichis squared, m/s 9.8 : UN HANGES S of our orbit is minimal, at 0.01671123. [the moon is our eccentric neighbor, at 3.315x Earth]. This Earth]. 3.315x at oureccentricmoonis [the neighbor, 0.01671123. at minimal, is ofourorbit 197M square miles [the moon is 7.4% of Earth SA & is actually smaller than the continent of Asia]. ofEarth7.4% moonis [the miles square 197M Asia]. ofcontinent the than smaller actually SA&is : C LBEDO NCLINATION OMPOSITION I A C ROM REA RAVITY how do we measure surface gravity of a gas giant gas ofa gravity do we measure surface how F eccentricity A G The :

Earth inhabitants take for granted the seemingly-endless, comfortable, life-sustaining spinning ofspinning comfortable, life-sustaining Earth granted for take inhabitants seemingly-endless, the NoCoAstro

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QUATORIAL ISTANCE EMPERATURE LANETARY RBIT LANETARY PIN URFACE URFACE T temperature degree 522 a has [moon degrees! variation day]. to night from bodies with clouds tend to have a higher albedo. Seasonal changes that affect cloud cover affect Earth’s albedo. Earth’s affect albedo. cover cloud affect that changes Seasonal albedo. higher a have to tend clouds with bodies moon has a stabilizing effect on Earth. onEarth. effect stabilizing a moonhas P forces forces E the planet… but did you know that we are are we that know you did but planet… the commoninthe are locks tidal double Interestingly, moon. the with lock’ tidal ‘double tortoise) a to tidal strong the systems, star double and satellites orbiting relatively-large inpairs ofclose, universe: why S of zero (x=0) is circular, a fraction (01)is O derivedis kilometerssun around of147M orbit ourclosest from number value A ourfarthest and kilometers. of152M orbit P D S of the gas giants in our solar system as well? That’s right, we beat out Uranus, which came in at a very a inat whichcame m/s 8.69 respectable Uranus, out beat we right, That’s well? as system oursolar in giants gas ofthe wait, But squared. S surprised be not may Earth’s that hear to terrestrialofthe greatest the is surfacegravity (just planets You planetarybodies. one than surfacegravity greater has planet little our that know you did However, squared). m/s 8.87 Venus’ inabove sneaking M OON DRIVES S UPERNOVA IRON W HEN GEOLOGY MIGRATION OF FOUND ON MOON: AND ASTRONOMY A RCTIC A supernova two-million years in COLLIDE: the past has left its mark on the ZOOPLANKTON : moon. New research has confirmed that Earth’s crust first formed just 160 Biological clock tied to the Evidence of this supernova has been million years after formation of our phases of the moon? found on Earth in deep-sea sediment solar system! samples and now in samples gathered The daily rising and setting of the sun on the moon from 1969 to 1972. Why does this matter? New research propels what is thought to be the is confirming the timeframe that Earth world’s largest migration: tiny Among other things this also makes it was a fiery ball covered in a magma zooplankton move from the near- possible for the researchers to infer ocean came earlier than previously surface waters down into deeper, the distance to the supernova event! thought, as did the Earth cooling to darker waters during the day to avoid became habitable earlier than we predators that rely on sight for finding thought as well! a meal. It turns out that the region can The research may help scientists be surprisingly active in the dark of the understand how other habitable polar night. planets may form.

April April , SciShow or . Wants you to just be Numberphile , Discusses ‘The Future of the Mind’ ‘The Future of the Mind’ Discusses

The Pale Blue Dot The Pale Veritasium ? Have you seen him on Qi yet? He talks on Qi yet? seen him you Have , WHO IS YOUR FAVORITE? FAVORITE? YOUR IS WHO Michio Kaku: with Jon Stewart. celebs: YouTube Maybe you prefer Sixy Symbols MinutePhysics Brian Cox: Brian about ewoks! Neil deGrasse Tyson: yourself. Carl Sagan: Carl Sagan: April NoCoAstro Paul Fleming: web-edit at NoCoAstro dot org web-edit Paul Fleming: Amanda Bell: ObjView at NoCoAstro dot org Trevor presMoriarty: at NoCoAstro dot org TREASURER &OUTREACH Greg Halac: treas at NoCoAstro dot org Bob Michael: vp at NoCoAstro dot org Dave Karp: sec at NoCoAstro dot org NEWSLETTER EDITOR VICE PRESIDENT SECRETARY PRESIDENT

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“Before we invented civilization our ancestors lived mainly in the open out under the sky. Before we devised artificial lights and atmospheric pollution and modern forms of nocturnal entertainment

we watched the stars. ”

― January Carl Sagan, Pale Blue Dot April

Pale Blue Dot: A Vision of the Human Future in Space (audio book) By: Carl Sagan April NoCoAstro

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