Related papers: The controversial pen of Edwin Holmes
A mechanism is proposed to explain the outburst of comet 17P/Holmes based on; (a) oxidation of water within the porous surface of the comet nucleus to form hydrogen peroxide (H2O2) through exposure to UV radiation, to energetic solar-wind…
In 1939 Albert Einstein wrote a technical article that argued against the possibility that a star can be contracted to a single point: particles making up the star would end up rotating at velocities that were too high. In the same year,…
Context. On October 24, 2007 the periodic comet 17P/Holmes underwent an astonishing outburst that increased its apparent total brightness from magnitude V\sim17 up to V\sim2.5 in roughly two days. We report on Wendelstein 0.8 m telescope…
Stephen Hawking's contributions to the understanding of gravity, black holes and cosmology were truly immense. They began with the singularity theorems in the 1960s followed by his discovery that black holes have an entropy and consequently…
After G. N. Lewis (1875-1946) proposed the term "photon" in 1926, many physicists adopted it as a more apt name for Einstein's light quantum. However, Lewis' photon was a concept of a very different kind, something few physicists knew or…
After Isaac Newton was knighted by Queen Anne in 1705 he adopted an unusual coat of arms: a pair of human tibiae crossed on a black background, like a pirate flag without the skull. After some general reflections on Newton's monumental…
Eleven years after its perihelion, comet C/1995 O1 (Hale-Bopp) is still active. Between October 20--22, 2007, we detected a diffuse coma of 180x10^3$km in diameter with a slight elongation toward N/S direction. The integrated brightness was…
In 1896, Edward Charles Pickering (1846-1919), Director of the Harvard College Observatory (HCO), reported in a trio of publications the observation of "peculiar spectra" of the southern star $\zeta$ Puppis, which he attributed to an…
Black holes are extreme spacetime deformations where even light is imprisoned. There is an extensive astrophysical evidence for the real and abundant existence of these prisons of matter and light in the Universe. Mathematically, black…
David Elijah Packer (1862-1936), a librarian by profession, was an enthusiastic amateur astronomer who observed from London and Birmingham. He first came to the attention of the astronomical community in 1890 when he discovered a variable…
Rather than offering chronologically ordered encyclopedic knowledge of a lifetime, only some of the most striking events of the existence of this well-known scientist are here pointed out. Sections: Life; Man of laws; Interest in…
Sir Arthur Eddington is considered one of the greatest astrophysicist of the twentieth century and yet he gained a stigma when, in the 1930s, he embarked on a quest to develop a unified theory of gravity and quantum mechanics. His attempts…
One of the greatest discoveries of modern times is that of the expanding Universe, almost invariably attributed to Hubble (1929). What is not widely known is that the original treatise by Lemaitre (1927) contained a rich fusion of both…
Until the second half of the 19th century, two or more brief appearances of bright comets, such as the ones in 1668 and 1702, alike in aspect and motion, seen with a tail near the Sun, were almost universally believed to be periodic returns…
Between 1974 and 1975, Stephen Hawking revolutionized the world of physics by proposing that black holes have temperature, entropy, and evaporate gradually. The objective of this article is to offer a brief and updated introduction to these…
We report high spectral resolving power optical observations of comet C/2017\,K2 (PanSTARRS) as it approached the Sun. This comet was discovered when it was 16\,{\sc au} from the Sun. At discovery, the comet had a large and relatively…
Einstein became world-famous on 7 November 1919, following press publication of a meeting held in London on 6 November 1919 where the results were announced of two British expeditions led by Eddington, Dyson and Davidson to measure how much…
Comets and asteroids have long captured human curiosity, and until recently, all documented examples belonged to our Solar System. That changed with the discovery of the first known interstellar object, 1I/2017 U1 ('Oumuamua), in 2017. Two…
Neptune was telescopically discovered by Johan Gottfried Galle and Heinrich Louis d'Arrest in Berlin on 23 September 1846 based on the prediction by Urbain Jean Joseph Le Verrier. The role German astronomers played in the discovery has…
This paper describes progress achieved in early investigations of the orbital motion and light curve of comet C/2026 A1 (MAPS), the third ground-based discovery of a Kreutz sungrazer in the 21st century. The highly unusual trait of the…