August 2025
On & Off Earth
The dawn rising of Sirius, the Dog Star, during the first week of August kicks off the Dog Days of Summer. Sirius, the brightest star visible from Earth, was thought by the Egyptians to add extra heat to the summer sun to make the season that much hotter; it does not. It did signal the annual flooding of the Nile which allowed one of humanities earliest empires to flourish in the desert.
Flooding, literally and figuratively, is all the rage these days. The surprise and shock shown at all of these flooding events is confusing to me as a geologist. The geologic reality that flooding is always confined to a river or stream and its adjacent FLOOD PLAIN is no surprise. It’s how water drains on Earth. I don’t mean to belittle the resulting tragedies but a structure built on a flood plain is eventually going to flood.
Our development of and success at agriculture is mostly the result of the clever use of flooding and flood plains. Sediments deposited in annual floods freshen the soil and restock the groundwater reserves. From Egypt to Mesopotamia, to the rice fields of Asia, to the flood plains of the North and South Anna rivers humans have farmed flood plains. The only structures built on local flood plains were the mills that ground the grains grown on nearby fields. Those mills were built to both help control and withstand the occasional flood.
Humans have always made ‘deals’ with Earth about where we live. If you are willing to live near a volcano, the rich soil makes agriculture a dream. Just heed the warning rumbles of that nearby mountain. We need water, daily, so we camped and later built near rivers and streams. Camping is fine, it’s easy to move when the rains come. Building ‘permanent’ structures, we continue to see, to withstand the power of rushing water is, long term, going to be a losing proposition. Bury a drain pipe, pave it over..it’s still a water channel with an adjacent flood plain and with bigger rains becoming the new normal, we’re going to have bigger floods.
There are two ‘stars’ far easier to spot than Sirius in the pre-dawn sky this month: Venus and Jupiter. Those bright planets will grow closer each day of August until they are less than 1° apart on the morning of the 12th. Ever on the move, they are 8° apart by the 19th when the waning crescent moon joins the show for three mornings. Mercury hangs just above the horizon throughout. The sun moves from Cancer into Leo on the 12th.
The Perseid meteor shower peaks on the night of the 12th/13th but will compete with a bright gibbous moon just 3 days past the Full Sturgeon moon. Stray Perseid’s can, however, blaze across the sky most any August night.
While August loses an hour of sunlight over the month, the month is still dominated by sunlight and the heat and humidity of a Virginia summer. Earth is, at some point, going to use that heat to spin up a hurricane or two. The Dog Days require that you be weather aware as you turn your vacation plans into action.
The near record July rains, (better than drought) seem to have delayed the ripening of my garden but the ‘maters and peppers and zucchini are coming. Remember, August 8th is ‘sneak a zucchini on your neighbor’s porch’ day; share the plenty!
And, yes, some dumbass in NOVA drove their SUV(Stupid Urban Vehicle) into a flooded road yesterday and was swept away...too bad not a Darwin Awardee..
Today On Earth
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