I hope it's still true that every first-year chemistry student learns something about Henry Moseley - at the very least, that his work with X-ray spectroscopy improved our understanding of the periodic table. Mendeleev had arranged the elements by atomic weight, and when their periodic properties did not line up the right way, suggested that the atomic weights had been incorrectly measured - Moseley, as I learned it, showed that atomic number is a physical property independent of atomic weight, corresponding as we now know to the number of protons. What some classes teach, though not all, is that Moseley volunteered for service in the First World War and was killed at Gallipoli in August 1915, as a second lieutenant of engineers. From the article I linked, I see that both his mentor Ernest Rutherford and his mother tried to dissuade him, but he insisted. (It also tells me he tried to leave the Engineers to join the Royal Flying Corps, in what capacity I do not know.) He was killed by a sniper while telephoning for reinforcements.
According to the wiki "[b]ecause of Moseley's death in World War I, the British government instituted a policy of no longer allowing its prominent and promising scientists to enlist for combat duty in the armed forces of the Crown." I'm not sure I approve, but at the hour I'm writing this, I can't articulate why.
Less well known, perhaps, is George Butterworth, a British composer and collector of songs, of the same generation as his friend Ralph Vaughan Williams. He destroyed a lot of his own work (because it didn't meet his own standards) and is best known for his arrangements of Houseman's "A Shropshire Lad." Many of these poems deal with death in a thoughtful way, and Butterworth's settings bring them out beautifully. Try one or two -- "Loveliest of Trees"...
Now of my threescore years and ten
Twenty will not come again,
And take from seventy springs a score -
It only leaves me fifty more...
And since to look at things in bloom,
Fifty springs are little room;
About the woodlands I will go
To see the cherry hung with snow.
If it doesn't read like much, hear it sung by a good baritone (as it is at the link I just gave you). Try "The Lads in their Hundreds," and "Is My Team Ploughing?"
Butterworth volunteered, enlisted, was later commissioned and promoted, and was mentioned in despatches and awarded the Military Cross for gallantry at the Somme, where he was killed by a sniper in August 1916.
Spare a moment for fallen genius.