Electronics World articles Popular Electronics articles QST articles Radio & TV News articles Radio-Craft articles Radio-Electronics articles Short Wave Craft articles Wireless World articles Google Search of RF Cafe website Sitemap Electronics Equations Mathematics Equations Equations physics Manufacturers & distributors Engineer Jobs LinkedIn Crosswords Engineering Humor Kirt's Cogitations RF Engineering Quizzes Notable Quotes Calculators Education Engineering Magazine Articles Engineering software RF Cafe Archives RF Cascade Workbook 2018 RF Symbols for Visio - Word Advertising Magazine Sponsor RF Cafe RF Electronics Symbols for Visio RF Electronics Symbols for Office Word RF Electronics Stencils for Visio Sponsor Links Saturday Evening Post NEETS EW Radar Handbook Microwave Museum About RF Cafe Aegis Power Systems Anritsu Alliance Test Equipment Amplifier Solutions Anatech Electronics Axiom Test Equipment Berkeley Nucleonics Centric RF Conduct RF Copper Mountain Technologies Empower RF everything RF Exodus Advanced Communications Innovative Power Products ISOTEC KR Filters PCB Directory Rigol San Francisco Circuits Reactel RF Connector Technology TotalTemp Technologies Triad RF Systems Windfreak Technologies Withwave LadyBug Technologies Wireless Telecom Group Sponsorship Rates RF Cafe Software Resources Vintage Magazines RF Cafe Software RF Cafe Sponsor Links Werbel Microwave Thank you for visiting RF Cafe!
Anritsu Test Equipment - RF Cafe

So Near, and Yet So Far
Kirt's Cogitations™ #128

RF Cafe University"Factoids," "Kirt's Cogitations," and "Tech Topics Smorgasbord" are all manifestations of my rantings on various subjects relevant (usually) to the overall RF Cafe theme. All may be accessed on these pages:

 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36

< Previous                      Next >

 

So Near, and Yet So Far

We can directly observe the composition of the rings of Saturn - 850 million miles away - but we still can't figure out what lies at the center of our Earth - a mere 4,000 miles away! Traditional theory suggests it is a solid core of nickel-iron, surrounded by a liquid region of iron, nickel, and a mix of sulfur, oxygen and silicon. A more avant-garde postulate claims a literal nuclear reactor core of uranium and plutonium, surrounded by a molten core of iron, sulfur and silicon. Both dynamo models account handily for the Earth's magnetic field - including the cyclic variations. The greatest hole ever drilled, on Russia's Kola Peninsula, is only 7.5 miles deep, or less than 0.2% of the way to the center. In geophysicist Herndon's words, "That's roughly comparable to learning about Alaska by driving from St. Petersburg, FL to Tampa."

everythingRF RF & Microwave Parts Database (h1) - RF Cafe
Exodus Advanced Communications Best in Class RF Amplifier SSPAs
Axiom Test Equipment - RF Cafe
Innovative Power Products Passive RF Products - RF Cafe
ConductRF Phased Matched RF Cables - RF Cafe

Please Support RF Cafe by purchasing my  ridiculously low−priced products, all of which I created.

These Are Available for Free

 

About RF Cafe

Kirt Blattenberger - RF Cafe Webmaster

Copyright: 1996 - 2024

Webmaster:

    Kirt Blattenberger,

    BSEE - KB3UON

RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The World Wide Web (Internet) was largely an unknown entity at the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps while tying up your telephone line, and a nice lady's voice announced "You've Got Mail" when a new message arrived...

All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.

My Hobby Website:

AirplanesAndRockets.com