The Tropics Defined: Sun Directly Overhead on July 31 in Punta Cana DR

July 31, 2024  12:30 Local Time

Check out the shadow at my feet.  The sun is directly overhead.  This happens here on July 31, shortly after noon.  We define "the tropics" as the area of the earth at which -- as some point in the year -- the sun will be directly overhead.   Here we are at about 18 degrees North latitude, so for us, the overhead date is July 31.  We are definitely in the tropics.  A good graphical description of what is happening appears here: 

https://www.suncalc.org/#/18.5548,-68.3853,12/2024.07.31/12:37/1/3

A = 97 K = 9

 

You have heard of the International Geophysical Year (IGY). But have you heard of the IQSY?

 

International Quiet Sun Year.  1964-1965.  Yes, that was a thing.  

The Carrington Event and the Current Solar Cycle (Solar Max "Sooner and Stronger")

 

From the article: 

"Sunspot activity has increased dramatically in early 2023, with sunspot numbers far exceeding NASA's predictions each month — though nothing as big as Carrington’s sunspots have been seen yet. Still, the profusion of sunspots and other solar weather suggests that the next solar maximum will arrive sooner and stronger than NASA previously predicted. Whether the incoming maximum brings with it a Carrington-level storm is a matter of pure chance — but scientists will keep watching for spotty signs on the sun, just in case."

https://www.yahoo.com/lifestyle/see-monster-sunspot-launched-carrington-120000667.html

WIRED on the Dangers of another Carrington Event, Solar Cycle 25, Capacitors Could Save Us All

This Wired article has some really interesting info on competing theories about the solar cycle, about the danger to the Earth from solar flares, and about what a flare like that of the Carrington event could do to the transformers we are currently using.  The article points out that large capacitors could protect these transformers from the effects of the flare.  But the power companies are not installing the capacitors. 

I think one of the scientists Pete mentioned in SolderSmoke podcast #238 is mentioned here: 

https://www.wired.com/story/sun-storm-end-civilization/?redirectURL=https://www.wired.com/story/sun-storm-end-civilization/

Good News! The Termination Event May Be Coming Soon! Solar Cycle 25 Could Rival Cycle 19!

Wow.  Cycle 25 might be as good or better than Cycle 19.  Pete cut his radio teeth on Cycle 19.  I was born during that cycle.  Let's hope these scientists are right!  See chart below. 

https://spaceweatherarchive.com/2021/06/11/the-termination-event/

Thanks to Thomas over at SWLing Post for alerting us to this important news.   

SolderSmoke Podcast #224: Mars. Spurs. Bikes. SDR. NanoVNA. Antuino. MAILBAG

SolderSmoke Podcast #224 is available:

http://soldersmoke.com/soldersmoke224.mp3

1 August 2020

--The launch of Perseverance Mars probe with Ingenuity helicopter.

--China’s Tian Wen 1 on its way – radio amateur Daniel Estevez EA4GPZ is listening to it! 

--Sci Fi Books:  Mars Trilogy by Kim Stanley Robinson.  No skip on Mars :-(

--We have some sunspots!  SFI now 72 and the Sunspot number is 23. 

Bill's bench: 

--Conquering Ceramic Spurs in Q-31   Roofing filter -- sort of 

--NE602 for a Q-75 converter – Gilbert Cell. 

--Measuring low power levels out of NE602.  Antuino better than 'scope . 

--NanoVNA   Really cool stuff.  SDR in there. 

--Building a 455 kc LC filter from QF-1 rubble. Using LTSPICE, Elsie... 

--Reviving my bicycle AM radio – The “All Japanese 6”

--Understanding L Network impedance matching. 

--Bill’s new resistor kit from Mouser. Thanks to Drew N7DA. 

SHAMELESS COMMERCE:  PATREON, AMAZON SEARCH.  THANKS

Pete's Bench: 

--Lockdown Special 

--BPF work on SDR Rig

--I U W I H 

Mailbag:

VK3HN Summit Prowler 7

VK2EMU “The Stranger”

SM0P  HB uBITX in Dubai

AE7KI  Worked him in VK from London

ON6UU  EA3GCY’s 4020 rig

KA4KXX A Simpler Mighty Mite

W9KKQ M19 DMR

KD4PBJ Radio Schenectady

W3BBO 12AU7 Regen

KE5HPY Another 12AU7 regen

N5VZH Ne602 Converter

KY3R Wall Art

G4WIF  Spectrum Analyzer in your pocket

W2AEW  Talks to UK Club

KK0S Sent 455 Kc IF cans

KL0S Making 9Mhz filters

VU2ESE  Diving into simple SDR schemes

Dean KK4DAS  Amateur Radio Astronomy

NOAA Prediction for Solar Cycle 25

A peak sunspot number of 115 might seem paltry, until you remember that we are at ZERO now. 

https://www.swpc.noaa.gov/news/solar-cycle-25-forecast-update

Transit of Mercury, 11 November 2019, and a Transit of Venus and Some Sunspots from 2012

Above:  Transit of Mercury, November 11, 2019 as I saw it from Northern Virginia using a 4.5 inch reflector with image projected onto a white paper.  Elisa took the picture with her I-phone.  Arrow shows Mercury.  I almost missed it -- Billy texted from college to remind me of the big event. 

Above:  Transit of Venus June 6, 2012 as seen from Northern Virginia.  Billy (age 13) took the picture with his I-phone 4.  Venus is much bigger, much closer and much easier to see.  Near the bottom edge of the solar disc. 

  

Above;  Billy on November 12, 2011 with the 4.5 inch Tasco Reflector that was used on BOTH the Venus and Mercury transits (we projected the image on paper). On this day we were using our newfound solar photography expertise to take a picture of sunspots (our picture below). 

Ah, those were the days!  Many spots back then.  None now. 

The First Sunspots of Cycle 25 -- Explained by Space Weather Woman (Video)

Dr. Tamitha Skov explains how Cycle 25 has begun while Cycle 24 is not quite finished. 
She has a very clear way of presenting the space weather.  Very useful. 

YouTube site: https://www.youtube.com/channel/UCkXjdDQ-db0xz8f4PKgKsag

1972 Solar Flare Caused Naval Mines to Explode

There are reports out this morning that a big solar flare in 1972 caused naval mines placed by the U.S. off the coast of Vietnam to explode.  

https://www.livescience.com/64062-mines-solar-storm-1972-vietnam.html

https://www.colorado.edu/today/2018/11/12/1972-solar-storm-triggered-vietnam-war-mystery

Background info: 

https://oraprdnt.uqtr.uquebec.ca/pls/public/docs/GSC418/F1929448428_Solar_Superstorm__Astronomy_Sept_2008.pdf

I remember this solar event.  It caused aurora near New York City: 

https://soldersmoke.blogspot.com/2009/09/carrington-flares-aurora-where-were-you.html

Pre-eclipse Solar Observation

I'm not sure if I'll be able to get a look at the eclipse tomorrow -- I'll be at work,  and in any case Washington DC will be far from the zone of totality.  But all the eclipse talk made me want to get my old 4 inch reflector telescope out today for at least one solar observation.  And yes, I know not to look through the 'scope. I projected the image onto a piece of white paper.   Notice the three large sunspots at the center of the solar disk.  Pretty cool.  

BTW, it is easy to aim the scope at the sun without endangering your eyesight.  Don't ever put your eye to an eyepiece (even on the spotting or aiming 'scope) when ole' sol is in the sky!  Instead, just look at the shadow that the scope tube is casting on the ground.  Make it circular and you will be very close to having the main tube aimed at the sun. See below.   

 I like to have the eyepiece aimed down at the ground or well above horizontal to avoid the danger of someone accidentally walking through  the powerful sunbeam coming out of the eyepiece.  You do have to be careful, especially if there are kids around.