Part 16

Cuspianus relates that a star as bright as Venus appeared near Altair in 389 A. D., during the reign of the Emperor Honorius, and that he had himself seen it. There is some doubt, however, about the exact date, as other accounts give the year 388 or 398. The star seems to have disappeared in about three weeks.

In the year 393 A. D., another strange star is recorded in the tail of Scorpio. An extraordinary star is said to have been seen near Alpha Crateris in 561 A. D. Here again a known variable and red star—R Crateris—is close to the position indicated by the ancient records.

The Chinese annals record a new star in 829 A. D., somewhere in the vicinity of the bright star Procyon, and in this locality there are several known variable stars.

The Bohemian astronomer, Cyprianus Leoviticus, mentions the appearance of new stars in Cassiopeia in the years 945 A. D. and 1264, and it has been conjectured that perhaps these were apparitions of Tycho Brahe’s famous star of 1572 (to be presently described), forming a variable star with a period of over 300 years. Lynn and Sadler, however, have shown that the supposed stars of 945 and 1264 were, in all probability, comets.

Extraordinary stars are recorded near Zeta Sagittarii in 1011 A. D., near Mu Scorpii in 1203, and near Pi Scorpii on July 1, 1584. It is remarkable how many of these objects seem to have appeared in this portion of the heavens.

A very brilliant star is mentioned by Hepidannus as having appeared in Aries in May, 1012. He describes it as “dazzling the eye.” Other temporary stars are mentioned in 1054 A. D., near Zeta Tauri, and in 1139 near Kappa Virginis; but the accounts of these are very vague, and it seems by no means certain that they were really new stars.

No possible doubt, however, can be entertained with reference to the appearance of the object which suddenly blazed out in Cassiopeia’s Chair in November, 1572. It was called the “Pilgrim Star,” and was observed by the famous astronomer, Tycho Brahe, who has left us a very elaborate account of its appearance, position, etc. Although usually spoken of as Tycho Brahe’s star, it seems to have been really discovered by Cornelius Gemma on the evening of November 9. That its appearance was very sudden may be inferred from Cornelius Gemma’s statement that it was not visible on the preceding night in a clear sky. Tycho Brahe’s attention was first attracted to it on November 11. His description of the new star is as follows—as quoted by Humboldt: “On my return to the Danish islands from my travels in Germany, I resided for some time with my uncle, Steno Bille, in the old and pleasantly situated monastery of Herritzwadt, and here I made it a practice not to leave my chemical laboratory until the evening. Raising my eyes, as usual, during one of my walks, to the well-known vault of heaven, I observed with indescribable astonishment, near the zenith in Cassiopeia, a radiant fixed star of a magnitude never before seen. In my amazement, I doubted the evidence of my senses. However, to convince myself that it was no illusion, and to have the testimony of others, I summoned my assistants from the laboratory, and inquired of them, and of all the country people that passed by, if they also observed the star that had thus suddenly burst forth. I subsequently heard that in Germany, wagoners and other common people first called the attention of astronomers to this great phenomenon in the heavens—a circumstance which, as in the case of non-predicted comets, furnished fresh occasion for the usual raillery at the expense of the learned. This new star I found to be without a tail, not surrounded by any nebula, and perfectly like all other fixed stars, with the exception that it scintillated more strongly than stars of the first magnitude. Its brightness was greater than that of Sirius, Alpha Lyræ, or Jupiter. For splendor, it was only comparable to Venus when nearest to earth (that is, when only a quarter of her disk is illuminated). Those gifted with keen sight could, when the air was clear, discern the new star in the daytime, and even at noon. At night, when the sky was overcast, so that all other stars were hidden, it was often visible through the clouds, if they were not very dense (_nubes non admodum densas_). Its distances from the nearest stars of Cassiopeia, which throughout the whole of the following year I measured with great care, convinced me of its perfect immobility. Already in December, 1572, its brilliancy began to diminish, and the star gradually resembled Jupiter, but by January, 1573, it had become less bright than that planet. Toward the month of November the new star was not brighter than the eleventh in the lower part of Cassiopeia’s Chair. The transition to the fifth and sixth magnitudes took place between December, 1573, and February, 1574. In the following month the new star disappeared, and, after having shone seventeen months, was no longer discernible to the naked eye.” (The telescope was not invented until thirty-seven years afterward.) Humboldt adds: “At its first appearance, as long as it had the brilliancy of Venus and Jupiter, it was for two months white, and then passed through yellow into red. In the spring of 1573, Tycho Brahe compared it to Mars; afterward he thought it nearly resembled Betelgeuse, the star in the right shoulder of Orion. The color for the most part was like the red tint of Aldebaran. In the spring of 1573, and especially in May, its white color returned (_albedinam quandam sublividam induebat, qualis Saturni stellæ subesse videtur_). So it remained in January, 1574; being, up to the time of its entire disappearance in the month of March, 1574, of the fifth magnitude, and white, but of a duller whiteness, and exhibiting a remarkably strong scintillation in proportion to its faintness.”

Ma-tuan-lin speaks of a star in 1578 “as large as the sun” (!) but does not state its position.

The star known as P (34) Cygni is sometimes spoken of as a “Nova,” or new star; but it is still visible to the naked eye as a star of the fifth magnitude. It was observed of the third magnitude by Jansen in 1600 and by Kepler in 1602. After the year 1619 it appears to have diminished in brightness, and is said to have vanished in 1621; but it may merely have become too faint to be seen with the naked eye. It was again observed of the third magnitude by Dominique Cassini in 1655, and it afterward disappeared. It was again seen by Hevelius in November, 1655. In 1667, 1682, and 1715 it is recorded as of the sixth magnitude, and there is no further record of any marked increase in its light. A period of about 18 years was assumed by Pigott; but this is now disproved, and it seems probable that the star is a variable of irregular period and fitful variability, and not, properly speaking, a temporary star. Its present color is yellow, and bright lines have been seen in its spectrum.

A new star of the third magnitude was observed near Beta Cygni by the Carthusian monk Anthelmus in 1670. It remained visible for about two years, and is said to have increased and diminished several times before its final disappearance. Schönfeld computed its exact position from observations made by Hevelius and Picard. Quite close to the spot indicated, a star of the eleventh magnitude has been observed at the Greenwich Observatory, and fluctuations of light were suspected in this small star by Hind and others.

A very remarkable star, sometimes called the “Blaze Star,” suddenly appeared in Corona Borealis, in May, 1866. It was first seen by the late Mr. Birmingham, at Tuam, Ireland, about midnight on the evening of May 12, when it was of the second magnitude, and equal to Alphecca, “the gem of the coronet.” Its appearance must have been very sudden, for Schmidt, the Director of the Athens Observatory, stated that he was observing the constellation on the same evening, about two and one-half hours previous to Birmingham’s discovery, and observed nothing unusual. He was certain that no star, of even the fifth magnitude, could possibly have escaped his notice. On the following night it was seen by several observers in different parts of the world.

A remarkable and very interesting temporary star was discovered in 1892 in the constellation Auriga.

It is a remarkable fact that the great majority of the temporary stars appeared in or near the Milky Way. The chief exceptions to this rule are: the star of 76 B. C., in the Plow, the star recorded by Hepidannus in Aries, 1012 A. D., and the “Blaze Star” of 1866 in Corona Borealis.

A WORLD ON FIRE—NOVA PERSEI.—ALEXANDER W. ROBERTS

In the small hours of the morning of 22d February, 1901, Dr. Anderson of Bonnington, Edinburgh, saw a bright star shining in the constellation of Perseus, where he knew no such star was ever seen before. The circumstances connected with this discovery afford another striking instance of how Nature keeps her secrets for her true amateur, using the word in its highest sense.

The evening of 21st February was cloudy, and nine out of ten astronomers would have gone to bed when there seemed little prospect of the night clearing; but Dr. Anderson was the tenth man. At twenty minutes to three in the morning the clouds rolled away from over the old gray Scottish capital, and the trained eye of the patient observer saw right in the heart of Perseus a new star. Never before had its light, blue-white, like an unpolished diamond, shone down on this strange earth of ours.

Next day the news of the wonderful discovery was flashed to all the great observatories of the world, and telescopes and spectroscopes, cameras and photometers, were directed toward the strange phenomenon, and by testing, measuring, examining, sought to wrest its secrets from it.

Much is still a mystery; but what has been ascertained during the period that the rhythm of its light-waves beat upon our shores is of great interest and importance as bearing directly on the life-history of each individual star in the heavens, and of our own sun and planet among them.

The first and simplest question that arises for settlement is the date when the new star blazed forth in our terrestrial sky. The curious reader will notice the reservation: in _our_ terrestrial sky. When the star _actually_ burst forth into resplendent light is another matter, as we shall discover later on. It was certainly before Dr. Anderson was born, and probably before another Scotsman—Ferguson by name—combined, like many another sage, counting and watching sheep with counting and watching stars.

With regard to the date of the appearance in our sky of the new star, Nova Persei, as it is called in astronomical literature, when Dr. Anderson discovered it at twenty minutes to three o’clock on the morning of 22d February, it was bright enough to be straightway evident to a trained astronomer. In these later days of strenuous scientific activities every portion of the sky is constantly being examined and charted, and no sooner was the discovery of Nova Persei announced than a searching of records began, in order to ascertain if, at any time, the star had ever been seen before.

[Illustration: Fig. 19.—Chart Showing Position of Nova Persei]

It so chanced that on the evenings of 18th and 19th February two photographs of the very spot where three days later the new star appeared were taken at Harvard Observatory. On neither of these photographs is there the slightest evidence of the star’s existence. It was, therefore, on these dates non-existent so far as our earth was concerned. On the evening of 20th February a well-known English observer, Mr. Stanley Williams, had also taken a photograph of the same portion of the sky; and again there was no trace of the star. Mr. Williams’s photograph was taken twenty-eight hours before Dr. Anderson saw it. Still more strange is the fact that on the evening of 21st February three observers on the Continent testify that they had the constellation Perseus under observation from seven o’clock to eleven, and had the new star then been visible they could not have failed to see it. The star, therefore, blazed out some time between eleven o’clock and three on the night of its discovery.

Now, what does this mean? It means this: that by some cause a star, quite dark before, or so faint that it could not be seen even by means of a powerful telescope, in a few hours, or perhaps in a few minutes, blazed forth as a star of conspicuous brightness. In this brief space of time a dark and probably chill globe became a seething mass of fire, a million times hotter than it was before. Fierce, fervent heat lit up the orb with a glow that reached from rim to rim of the stellar universe. We have here a catastrophe that goes beyond our wildest conceptions: the conflagration of a world, the ruin of a star. What guarantee have we for an assumption of this kind? What of certitude is there in our vision of such a Day of Doom for any part of our universe? Let us consider the salient facts regarding the recent changes in the appearance and structure of this star. We shall relate only those facts that are beyond controversy, as far as our present knowledge goes.

Nova Persei did not reach its maximum brightness till the evening of 25th February, when it was probably the most conspicuous object in the midnight sky. It was then at least six times brighter than at the time of its discovery. After this date it began to wane slowly. At intervals there were spurts of brightness lasting for two or three days, as if the fires had not exhausted themselves. On the whole, however, the light of the star waned, and by the end of the year its enfeebled light was just bright enough to be evident to the naked eye; twelve months after its appearance it could only be seen with the aid of a telescope.

Now, one of the most powerful instruments of research in the new astronomy is the spectroscope. It takes hold of the rays of light that come to us from a star, and makes these rays reveal the condition of things in the world they come from. One of the spectroscopes turned on the new star in Perseus was Professor Copeland’s magnificent instrument at Blackford Hill Observatory, Edinburgh. Professor Copeland described the new star as “a feebly developed” sun. As the star, however, increased in brightness the spectroscope chronicled the fact that great physical changes were taking place in its composition and structure. The star soon ceased to be a feebly developed sun, for development had gone on apace with the increase of light. Round the solid or semi-molten mass there was rapidly aggregating an ocean of fiery gases, probably thrown up from the nucleus.

Put simply, Nova Persei, for long ages a cold, dark, solid globe, was in the brief space of a few days transformed from circumference to core into a luminous, heated gaseous sphere. By what chance or circumstance this vast change came about may be inquired into later on. We only note here that this was the story spelled out by those skilled in deciphering the observations recorded by the spectroscope. In July, 1901, Professor Pickering of Harvard Observatory announced that the star had become a nebula; that, indeed, its once solid globe had practically dissolved into thinnest air. Not only had its elements become molten with fervent heat, but they had become transformed into shimmering wisps of matter more diaphanous than a gossamer web.

Everything connected with the history of this star is of exceptional interest; but all that had already been ascertained was completely overshadowed by the astonishing discovery made in November, 1902, that nebulous prominences were observed darting out from the star with a velocity of at least 100,000 miles every second of time. These astonishing changes have been confirmed at the two great American observatories, the Yerkes and the Lick.

Whence and how had destruction come upon this particular star? At one hour the star is dark, cold, solid. A few hours later this dark, solid, cold body is a blazing world, its solid mass blown apparently into countless fragments; from every fragment, big or little, there pour streams of fiery vapor; for millions of miles round the star there is a whirlpool of fire, a tempest of flame; and from end to end of this great universe of ours the brightness of the burning star pulsates. Three explanations have been given.

The one that naturally arises in our mind is that it was struck by another star. Two worlds, each moving at the rate of twenty miles a second, come into collision, and the result is the annihilation of both. The force of their impact, changed into heat, drives their elements into vapor. Such a catastrophe is quite possible in a universe like ours, where stars and worlds, millions and millions in number, sweep down the great avenues of space with a velocity far beyond our comprehension.

We take it that when the crack of doom comes to this earth of ours it will be in this fashion. Some great dark star will strike our sun fair and square, and then in the twinkling of an eye, before the inhabitants of earth know what has taken place, sun and moon and planet will be wrapped up and dissolved in an atmosphere of fire.

We can in a certain rough way compute the increase in temperature that would arise from the collision of two great orbs. Thus, let us suppose that Nova Persei was moving onward through space with a velocity of ten miles a second—a moderate velocity, be it noted, for a star—when it collided with the body that wrought its destruction. The impact would be terrific, and the result of it would be not only the complete disintegration of both stars, but a sudden rise in temperature of about five hundred thousand degrees, an increase sufficient to vaporize the hardest adamant.

The second theory which has been suggested as explanatory not only of Nova Persei, but of all new stars, is a modification of the foregoing. This theory is that the new star in its flight through space suddenly plunged into a nebula, or into some portion of space denser than that through which it had already passed. This explanation is not only intelligible but reasonable. If the new star plunged into a region filled with matter even as rare as air, the friction would immediately set the star on fire. We see the same phenomenon every night when a meteor hustles through our atmosphere. The meteoric rocks, with the chill of empty space in and around them, dash into our upper air. A few seconds are ample for the practical annihilation of most of them: in that brief space of time they have been subjected to a heat many times greater than that of a Bessemer furnace.

We can imagine Nova Persei as some monster meteor, a meteor larger than the sun, plunging into a gaseous mass somewhat like our air. In a few hours its temperature would be increased a million-fold. This increase would fill the surrounding space with fire, and there would be an immense and ever-increasing area at fervent heat.

To the mind of the writer this explanation has most to commend it. It is the one that is most in harmony with the information which has been gathered by hundreds of observers aided by the finest of modern scientific equipment. But there are other explanations. There will always be other explanations so long as the world lasts.

One of these explanations is of more interest than the rest, inasmuch as it makes a link of connection between the recent terrible volcanic eruption in the West Indies and the sudden appearance of a new star like Nova Persei. It is suggested that Nova Persei is, or rather was, a world somewhat like our own, only vastly larger—that is, there was an inner core of molten matter and an outer shell of solid material. One day, according to the explosion theory, this outer shell burst, and the interior fires rushed hither and thither like a devouring flood all over the stellar globe. Vast chemical changes went on as the lambent flames turned everything solid into streams of lava. Great electrical disturbances took place all round the star. The whole phenomenon of Nova Persei, according to this theory, is just the destruction of St. Pierre on a sidereal scale.

Such a doom, of course, is possible in any star or planet whose interior is still molten. At any moment the imprisoned fires might break their barriers and change a cold, fruitful, life-bearing earth into a furnace; but it is far from probable that any such fate will ever be meted out to our planet or to any other, and, at any rate, destruction did not come to Nova Persei in this manner. No explosion could account for an access of heat and light any way comparable to that which was observed. Neither could any interior disruption be violent enough to hurl the star into fragments. The gravitational hold of the star would prevent this dismemberment. Yet during the ages the mind of man has been irresistibly drawn to this conception of the world’s end, so much so that perhaps, after all, our instinct is right and our science wrong, and the vision of the Minorite Celano of the

Dies iræ, dies illa Solvet sæculum in favilla,

is a vision of those things that will be in the later days.

We have already touched on one strange circumstance connected with the appearance of Nova Persei. Dr. Anderson saw it for the first time at a few minutes to three o’clock on the morning of 22d February—that is, the news of the strange occurrence reached our planet then; but when did the event actually take place?

At Greenwich and at some of the other foremost observatories attempts have been made directly and indirectly to determine the distance of Nova Persei. And yet this distance defies measurement. The star is so far away that we have no instruments refined enough to deal with the problem. But we know that the sudden blazing up of Nova Persei was over and done with before our great-grandfathers were born. It happened more than two hundred years ago—perhaps two thousand years ago. All this time the news was swiftly traveling earthward, traveling on and on and on, two hundred thousand miles every second of the clock, past star and nebula and system, never halting, never faltering—yet it took hundreds of years to come to us; and beyond us lie countless worlds that will not see the new star for centuries to come. Hundreds of years hence in _their_ sky will appear suddenly in the constellation of Perseus a strange star; it will increase in brightness for a few days just as it did in ours; it will fade away intermittently just as it did in ours. There is no imagination here; only sober facts.