Wednesday, March 11, 2026

March 1943: Missed Opportunity

The best month for U-boats fighting North Atlantic convoys wasn't early in the war but rather late--March 1943. "Gray wolves" scored against six eastbound convoys, sinking a total of 40 ships. The greatest success was achieved during the battles with convoys HX 229 and SC 122. Twenty two merchant vessels were sent to the bottom. Alarmed, Churchill was determined to redouble efforts against the reich's submarines, and sink one of every three that left port.

The German success of March 1943 has been exaggerated by some historians, who claimed it came close to severing the Allied supply line in the North Atlantic. Prior to Blair's second volume, which challenged the claim, it was common to assert that the reich came close to winning the Battle of the Atlantic. In fact, as Blair noted, the losses of March 1943 represented only about 8% of allied ships sailing that month in eastbound convoys.

The significance of the German success may have have been overblown. Is it possible, though, the Germans could have won the Battle of the Atlantic, even if they did not?

In The U-Boat Wars, Edwin Hoyt covered March 1943 in the chapter "The Jaws of Victory." Like a number of other authors, Hoyt considered the situation, after "the enormity of the disaster," to be "very black indeed." It wasn't that bad, but Hoyt included something which suggests the Allied situation could've become significantly worse.

During the pivotal battle against HX 229, Hoyt wrote that at one point the convoy was defenseless as its escorts were all busy rescuing survivors or chasing U-boats. Yet, despite a golden opportunity to inflict more losses, "four perfectly sound U-boats failed to attack." He did not say which U-boats they were; perhaps U-228, U-439, U-448 and U-445. None seem to have had aggressive commanders as they never hit anything. But what if they did attack? Given lack of escorts, it wouldn't have been difficult for the four to sink an average of two each, or 8 total. That would've doubled the score that night (March 16-17). Even as escorts returned or reinforcements came, the need for additional rescue operations would've prolonged the defenseless state of the convoy. If this situation persisted another 48 hours--until dawn on the 19th, when U-boats broke off attacks--HX 229 might've been annihilated. Instead of sinking a total of 13 ships the Germans might've sunk over three dozen. They had no shortage of boats; over 40 were available to fight HX 229 and SC 122. Destruction of the former would've boosted the total loss to about 45 ships, or over twice the historical toll. The total haul for March (just HX/SC convoys) would've been around 65.

Destruction of an additional 25 ships wouldn't have won the war. Even worse than the material losses, however, would've been the psychological blow. Annihilation of a whole convoy would've undermined faith in the convoy system. It could've badly hurt morale. After a slaughter like that, at the first sign of U-boats, many ship masters would've ordered their vessels to leave their convoys. Sinkings might've remained high even in the spring when, historically, the U-boat casualties of "Black May" effectively decided the Battle of the Atlantic. That could've been avoided, or mitigated.

Thursday, February 12, 2026

Origin of the Sauropod Hiatus

For over 60 million years North America harbored sauropods. At times, the iconic beats attained gigantic size, high diversity and ecological dominance. Even after the demise of Morrison forms, Mierasaurus, Cedarosaurus and others document the survival of North American sauropods to the Cenomanian. The group then vanished, however, not to reappear until middle Maastrichtian time. Sauropods remained absent for almost the entire late Cretaceous (roughly 98 to 69 Ma).

What caused this loss of sauropods, known as the North American sauropod hiatus? Locally, two factors doomed the group. The first, or primary cause, was the late Albian highstand. Just prior to the end of the Early Cretaceous, sea levels rose precipitously, inundating a great deal of land and habitat. Naturally the most severely affected taxa were the largest ones, requiring the most habitat and food resources. No doubt, a key victim was the huge Abydosaurus. Existing just prior to Mussentuchit or Cenomanian time, Abydosaurus was bereft of resources needed for survival and died out. This extinction, however, did not mark the onset of the hiatus.

The lower horizon of the Mussentuchit has yielded tiny sauropod teeth. These teeth indicate the presence of a dwarf sauropod probably related to Astrodon. At a time of greatly diminished resources, only a diminutive sauropod, requiring minimal habitat and food, could persist. The lower Mussentuchit taxon certainly outlasted the giant Abydosaurus. It did not not last much longer, however. The highstand was to ultimately prove fatal, for the survival prospects of a small sauropod were not good.

The Mussentuchit documents an influx of Asiatic taxa into North America. Among these were Eolambia a hadrosauroid. Naturally the Mussentuchit sauropod was a low feeder. It could not reach the higher tree foliage. Dependent on low vegetation, it now faced competition from ornithopods. Even worse, it may have faced a large predator, Siats. Generally sauropod behemoths had little trouble surviving theropods, even big ones. In contrast, the little taxon stood no chance. Faced with invasive species, it appears to have succumbed quickly. The little sauropod existed just prior to the hiatus.

The fact a dwarf sauropod survived the Albian highstand, however briefly, indicates sea level changes were not the actual cause of extinction. Most likely, competitors and predators were. Nevertheless, by compelling sauropods to become small, the highstand effectively doomed them. Unless they were island dwellers, inaccessible to competitors or dangerous hunters, they lived on borrowed time.

Astrodon, a close relative of the later, Mussentuchit astrodont.

Wednesday, January 21, 2026

Investigating the Martian Atmosphere 1931

Spectroscopic studies have long been a means to determine the atmospheric composition of planets. From the start, there was a problem, however: distinguishing the gases of another planet from those of Earth's atmosphere.

An old c 1940 work, The Story of the Starry Universe mentioned this problem in regards to studies of the Martian atmosphere, and the solution. Two Mt Wilson astronomers, Walter S. Adam and Theodore Dunham jr, used "very high dispersion." The book did not go into detail on the method employed, which involved the Doppler effect. The astronomers timed their observations to make the best use of it.

January 1931 witnessed an aphelic opposition of Mars. The Red Planet was virtually at its greatest distance from the sun, which slowed its orbital speed. At the same time, Earth had just passed the perihelion point of its orbit, which meant it was orbiting the sun at virtually maximum speed. Since Mars was moving at its slowest while Earth was at its fastest, the Red Planet was receding from Earth at its most rapid rate. Mars always moves more slowly than Earth, but in January 1931 it was falling behind, i.e. moving away, more quickly than usual. Under those circumstances, the spectrum of Mars was redshifted. The Doppler effect was sufficient to separate the Martian absorption lines from those of Earth (or its atmosphere).

No doubt, Adam and Dunham noted the presence of CO2 in the Martian atmosphere, as CO2 is its primary constituent. Almost certainly, they also detected H2O.

On Mars as on Earth, aphelion coincides more or less with the onset of northern summer. The north polar cap of Mars wanes, releasing large quantities of water vapor. Owing to the limited heat received while Mars is farthest from the sun, polar ice does not melt. It does however sublimate. H2O forms wispy clouds drifting southward. The research of Adams and Dunham may have been well-timed to detect water.

Yet based on the limited evidence available, the researchers also concluded the Martian atmosphere was quite thin. This realization doused cold water on the popular notion of an inhabited Red Planet.

Mars during its latest aphelic opposition (January 2025). Mars presumably looked like that when at opposition on January 27, 1931. Note the wispy clouds extending from the pole southward, as Martian ice sublimates and drifts away.

Monday, December 01, 2025

Alleged Airstrikes 1973

The 1973 war began with air attacks on Israeli positions in Sinai and the Golan heights. About 200 Egyptian and 100 Syrian jets participated in these attacks. Most accounts of the Syrian raids indicate they were confined to the Golan. There is a notable exception, however. In Volume 5 of the ARAB MIGs series, Cooper et al. include accounts of SAF attacks inside Israel proper and even as far as the southern West Bank.

Thirty-six Syrian jets supposedly carried out these "deep penetration" raids. Twenty-four MIG-17s are said to have struck HAWK sites near Kfar Giladi and Tiberias, and also hit the Electronic Warfare (EW) center of the IDF Northern Command at Rosh Pina. In addition, it is claimed, 12 SU-20 fighter bombers, escorted by 8 MIG-21s, blasted the IDF/Air Force control center at Hebron in the West Bank.

Strangely, even though the reports are considered factual, no source corroborates them or mentions any results. No Palestinian from Hebron, no Israeli along the flight paths of the putative missions, or airmen presumably sent to intercept them, have ever confirmed these missions took place.

The alleged strike on a target in Hebron, in particular, doesn't appear to be credible. Syrian ORBAT data from Volume 5 indicates Syria's SU-20s (54 Squadron) were based at T-4, north of Damascus. That's pretty far from Hebron. The limited range of Soviet made aircraft would've been a problem, especially if the SU-20s were carrying bombs. A worse issue was the extremely risky nature of such a mission. To reach Hebron, 54 Squadron had to fly farther south than major Israeli airbases, notably Ramat David and Tel Nov. Almost certainly, Israeli interceptors from those bases, and others, would've intercepted 54 Squadron and its escorts. IAF Mirages would've shot down several jets and forced the others to jettison their bombs and flee. Even if there was no resistance before the AF control center was hit, the SU-20s and MIGs would've suffered losses on the way back. To improve morale in the dark first days of the war, the Israelis would've displayed wreckage from their kills. It's noteworthy that even in Sinai, where few Israeli Mirages were based, the defenders had two successes. They downed four SU-7s in one action and 7 jets in another, near Sharm el Sheik. Lack of similar reports from the northern front argues the putative missions are fictitious. They probably came out of a Syrian's imagination, long after the war. Even Cooper et al hint the attacks are bogus since they wrote no information about their results is known from any source.

An Su-20 jet.

Monday, November 17, 2025

Positions of Mercury

Back in the '70s I assumed that whenever an inferior planet reaches maximum elongation (east or west) the radius vector of the planet is perpendicular to that of Earth. Logically, it seemed, the two radius vectors form a right angle whenever the angular distance of Mercury (or Venus) from the sun, as seen from Earth, is at its greatest. For example, if Mercury is at greatest western elongation when Earth is at heliocentric longitude 270 degrees, Mercury "must" be at heliocentric longitude 180 degrees. To appear farthest from the sun, I imagined, the radius vector of Mercury couldn't be less than 90 degrees away from Earth's, since the planet wouldn't be fully elongated to one side of the sun.

As the diagram above makes clear, this reasoning was fallacious. Maximum elongation doesn't occur when the radius vectors form a right angle. It occurs when they form an acute angle. The separation of the two radius vectors, at farthest elongation, is far less than the "logical" 90 degrees. It's only about 60 degrees. A line from Earth to Mercury (when at maximum elongation) and beyond is farther from the sun than an Earth-Mercury line when the radius vectors are perpendicular. That proves the angle between Mercury and the sun, as seen from Earth, is not at its greatest when the radius vectors are 90 degrees apart.

Why does reality, in this case, seem to defy logic? It's due to varying distances. When the radius vector of Mercury is perpendicular to Earth's, the planet is farther away from us than it is when at greatest elongation. When the planet is farther its angular distance from the sun appears less. Conversely, when it is nearer its angular separation is greater. If Mercury was much farther away its separation from the sun would be much smaller; if the distance were vast the two bodies would appear to merge. So it's not surprising the angular sun-Mercury distance appears greatest when the planet is closer to Earth, instead of when its radius vector is 90 degrees from ours.

Addendum I

When Mercury is at full elongation its radius vector is perpendicular to a line from Earth to Mercury. But that's irrelevant. A line from Earth to Mercury is not a radius vector (a line from planet to the sun).

Addendum II

This fall marks the 20th anniversary of the blog! It's great to see it's still extant and receiving more pageviews than ever. Thanks to all who contributed over the years!

Thursday, October 02, 2025

Old Views

From an old encyclopedia c 1940. In just 25 years space missions made a mockery of such views. Beginning in 1965, a plethora of rocket ships reached Mars and many other places. Men landed on the moon.

There are lessons in this today. Some people dismiss predictions of voyages to the stars, or UFO reports, claiming that interstellar distances make them impossible. Numerous UFO cases make a mockery of that. Ample experience shows it is unwise to underestimate the possibilities spawned by technological advances.

The planetary data in the old work also requires comment (click for better view). The info on Mercury's density and gravity is erroneous. The innermost planet is not 17% denser than our world. Its density is slightly less, or 98% that of Earth. Likewise, Mercury's gravity is lower than 44% of ours; it's just under 38%.

In contrast to the Mercury data, that for Mars is fairly accurate. Mars has long been the best known planet in the solar system. It is easier to study than Mercury, which is smaller, never gets as close as Mars does occasionally and is too close to the sun for proper observation. The Red Planet also has satellites, enabling researchers to accurately calculate its mass and gravity. It's not surprising the astronomers of a century ago erred about the innermost planet.

Saturday, August 23, 2025

Blockade Runners

After the British imposed a blockade on Germany in 1939, the Germans had to find ways to import vital commodities. One way was blockade running. Merchant ships attempted to slip past blockading forces to deliver cargo. The latter usually consisted of rubber, tungsten, tin, vegetable oil etc. These products were vital for the German war effort. It attests to the German need for them that they resorted to such a method.

Blockade running was a very risky undertaking. After obtaining cargoes in Japanese territory, vessels had to traverse the Indian Ocean, the Cape of Good Hope and much of the Atlantic before reaching Bordeaux in German-held France. They had to sail across thousands of miles of ocean, all completely dominated by the navies of the allies. If an enemy warship showed up, a blockade runner had no hope of resisting. It could only scuttle to prevent capture.

In the early years of the war, blockade running worked fairly well. As late as November 1942, three vessels--the Kulmerland, Dresden and Tannenfels--reached France with thousands of tons of rubber and other cargo. Immediately afterwards, however, the allies effectively shut down Axis blockade running. Because of Enigma decripts, the allies knew when and where Axis ships would appear and positioned warships to attack them.

Of the 10 blockade runners heading for France in late 1942/early 1943, 9 were sunk or forced to turn back. Three--the Rhatkotis, Hohenfriedburg and Regensburg--were sunk by British cruisers waiting in ambush. One, the Doggerbank, was accidently sunk by U-43. Another, the Ramses, scuttled after blundering into an allied convoy. Encounters with allied forces also caused the loss of Karin and Irene. The only vessel to reach Bordeaux--the Pietro Orseolo--had been torpedoed by a US sub, but luckily didn't incur fatal damage.

Vessels headed for Japan in this period fared little better. Only two, out of several, reached their destination.

Despite the disasters of early '43 the Germans, desperate for vital material, tried again in 1943-44. The results were hardly better. One ship, the Osorno, reached France but 4 others were sunk. Even in the Bay of Biscay, in December 1943, the Germans lacked the strength to protect blockade runners. Soon afterwards, in early 1944, allied warships picked off the last of them to try--the Rio Grande, Weserland and Burganland. Due to the heavy losses Hitler and Doenitz agreed to end attempts at blockade running with surface ships.

Beginning in 1943, the Germans and Japanese attempted to ship cargo via submarine but the results were poor.

German blockade runner badge of WWII. It was awarded to crews who successfully brought cargo to Gerrman-occupied France or assisted in the scuttling of vessels to prevent capture by the allies.