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Fermi's Piano Tuner Problem

How Old is Old?

If the Terrestrial Poles were to Melt...

Sunlight Exerts Pressure

Falling Eastward

What if an Asteroid Hit the Earth

Using a Jeep to Estimate the Energy in Gasoline

How do Police Radars really work?

How "Fast" is the Speed of Light?

How Long is a Light Year?

How Big is a Trillion?

"Seeing" the Earth, Moon, and Sun to Scale

Of Stars and Drops of Water

If I Were to Build a Model of the Cosmos...

A Number Trick

Designing a High Altitude Balloon

Pressure in the Vicinity of a Lunar Astronaut Space Suit due to Outgassing of Coolant Water

Calendar Calculations

Telling Time by the Stars - Sidereal Time

Fields, an Heuristic Approach

The Irrationality of

The Irrationality of

The Number (i)i

Estimating the Temperature of a Flat Plate in Low Earth Orbit

Proving that (p)1/n is Irrational when p is a Prime and n>1

The Transcendentality of

Ideal Gases under Constant Volume, Constant Pressure, Constant Temperature and Adiabatic Conditions

Maxwell's Equations: The Vector and Scalar Potentials

A Possible Scalar Term Describing Energy Density in the Gravitational Field

A Proposed Relativistic, Thermodynamic Four-Vector

Motivational Argument for the Expression-eix=cosx+isinx

Another Motivational Argument for the Expression-eix=cosx+isinx
Calculating the Energy from Sunlight over a 12 hour period
Calculating the Energy from Sunlight over actual full day
Perfect Numbers-A Case Study
Gravitation Inside a Uniform Hollow Sphere
Further note on Gravitation Inside a Uniform Hollow Sphere
Pythagorean Triples
Black Holes and Point Set Topology
Additional Notes on Black Holes and Point Set Topology
Field Equations and Equations of Motion (General Relativity)
The observer in modern physics
A Note on the Centrifugal and Coriolis Accelerations as Pseudo Accelerations - PDF File
On Expansion of the Universe - PDF File

Of Stars and Drops of Water

Moving outward from the solar system: The next closest star to Earth beyond the sun is Proxima Centauri, at a distance of 4.3 light-years (i.e., 4.3 x 6 trillion miles). It is one among billions in our galaxy, the Milky Way. The Milky Way is a pinwheel of stars 2,000 light-years "thick", and 100,000 light-years in diameter. It holds over a hundred-billion (one followed by 11 zeros) stars. The next closest spiral galaxy is M31 in the constellation Andromeda. It is nearly 2 million light-years away (12 million-trillion or 1.2 x 1013 miles). M31 is near the limit of naked eye visibility. The Hubble telescope extends the limit of visibility out to 10 billion (10,000,000,000) light-years. From Hubble, we estimate that there are about 50 billion (50,000,000,000) galaxies in the observable universe! And if each galaxy contains a hundred-billion stars, then the observable universe contains 5,000,000,000,000,000,000,000 ("5" followed by 21 zeros or five "sextillion") stars. By contrast, a cube of water, one inch on a side, contains about 600,000,000,000,000,000,000,000 ("6" followed by 23 zeros, or six-hundred sextillion) molecules! There are 120 times more water molecules in the cubic inch of water than there are stars in the observable universe!!!

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Responsible NASA Official: Theresa.M.Scott (Acting)