The distance of this remarkable comet from the sun at its perihelion passage was less than that of any known comet.
The perihelion portion of its orbit lies between the orbits of Mars and the earth, and the aphelion part is outside the orbit of Mars.
According to Mr. Denning, "most of the periodical comets at perihelion are outside the earth's orbit, and hence it follows that they escape observation unless the earth is on the same side of the sun as the comet.
Besides those already mentioned there are many comets with orbits of such marked eccentricity that their ellipses when near perihelion cannot be distinguished from parabolæ.
It has been calculated that if one of these asteroids be arrested in perihelion by the solar atmosphere, the quantity of heat thus developed will be 9000 times greater than that produced by the combustion of an equal mass of coal.
A change, moreover, in the perihelion distance will account for the occasional increase or diminution of the apparent magnitude at the different maxima of the same star.
Were the eccentricities of the nearest asteroids equal to that of Faye's comet, they would in perihelion intersect the earth's orbit.
The resisting medium through which they pass in perihelion must gradually contract their orbits, or, in other words, diminish the intervals between consecutive maxima.
Finally, if the matter of an elliptic ring should accumulate in a single mass, so as to occupy a comparatively small arc, its passage through perihelion might produce the phenomenon of a so-called temporary star.
Strength was lent to this hypothesis by the fact that the comet of 1882 was apparently torn asunder during its perihelion passage, retreating into space in a dissevered state.
Investigation showed that it was moving in an orbit which should bring it back toperihelion every five and a half years; yet it had never been seen before and, although often searched for, has never been seen since.
What had happened was that the comet in passing its perihelion point had swung exactly between the earth and the sun.
The effect is very small, and not thoroughly proved; but, so far as it goes, the evidence points to a greatly extended rare solar atmosphere, which rubs some energy out of it at every perihelion passage.
The solar tide varies between aphelion and perihelion from 1·9 to 2·1.
Newcomb found an excess of motions in the perihelion of Mars amounting to about 5' per century.
In spite of these objections, there can be little question that the eccentricity of the earth's orbit and the precession of the equinoxes with the resulting change in the season of perihelion must have some climatic effect.
The motion of Mercury's perihelion would therefore be 7" in the theory of Lorentz and 5".
At present the earth is about three millions of miles nearer the sun inperihelion than in aphelion.
We have referred to the fact that the earth reaches its perihelion point a little earlier each year, and, as a consequence, we would have periods of mild climate alternating the cold.
At present the earth passes its perihelion point in the Winter of the Northern Hemisphere, and its aphelion point in the Summer.
It will be readily seen that the more elliptical its orbit becomes the greater will be the difference between the perihelion and aphelion distance of the sun.
Hence, if Mr. Croll be correct, a period of high eccentricity would certainly produce a climate in the Northern Hemisphere such as characterized many of the mild interglacial epochs as long as the earth passed its perihelion point in Winter.
But the earth has not always reached its perihelion point during the Winter season of the Northern Hemisphere.
The intense light of a comet at perihelion is analogous to the charcoal points of a galvanic battery, caused by a rapid current of ether from the nucleus, and assisted by the radial stream of the vortex.
In 1744 a brilliant comet exhibited six distinct tails spread out like a fan, some seven days after its perihelion passage; its distance from the sun at the time not being more than a third of the earth's distance.
We have, also, a satisfactory explanation of the rapid formation of the tail; of its being wider and fainter at its extremity; of its occasional curvature; and of its greater length afterperihelion than before.
We may also conceive, that the continual siftings which the nucleus undergoes at each successive perihelion passage, have left but little of those lighter elements in comets whose mean distances are so small.
Since Pluto’s perihelion distance is less than that of Neptune, this experiment is one which Nature actually performs at times.
In astronomy, the angle which a line drawn from a planet to the sun has passed through since the planet was last at its perihelion or nearest distance to the sun.
The majority of comets are simply small, fuzzy points of light that are only visible telescopically and the greater the perihelion distance of the comet the less likely is it to be seen with the naked eye.
As the comet again recedes from the sun after perihelionpassage its speed slackens once more.
The majority of all comets observed have come within the earth's orbit and no known comet has its perihelion beyond the orbit of Jupiter.
I should be burned and rent to pieces amid the terrors of its perihelion passage, and my fragments would be strewn along the comet's orbit, to become, in course of time, particles in a swarm of aerolites.
And, as it falls, like any other falling body it gains in speed, until, having reached the perihelion point, its terrific velocity counteracts its approach and it begins to recede.
From these telltale plates it was ascertained that in 1894 it had been in perihelion very near the earth, and had shone with the brilliance of a seventh-magnitude star.
Now, being swept along by the comet, whose perihelion probably lay in the immediate neighborhood of the sun, I saw no way of escape from the frightful fate of being broiled alive.
When in aphelion, or at its greatest distance, Eros is outside of the orbit of Mars, but when in perihelion it is so much inside of Mars's orbit that it comes surprisingly near the earth.
For the motion from the Perihelion to the Aphelion, this representation makes the forces pass into the opposite relation in the same manner.
The perihelion distance from the sun, which settled the precise form of the parabola.
It was observed in Europe after three days, became just discernible by the naked eye at the end of July, and brightened consistently up to its perihelion passage, August 22, when it was still about fifty million miles from the sun.
The missing comet was next due at perihelion in the year 1872, and the probability was contemplated by both Weiss and Galle of its being replaced by a copious discharge of falling stars.
Each return to periheliontook place about two and a half hours sooner than received theories warranted.
At perihelion it penetrates within the orbit of Mercury; it considerably transcends at aphelion the farthest excursion of Pallas.
It was devoid of tail, or any other kind of appendage; and the rapid loss of the light acquired during perihelion passage was accompanied by inordinate expansion of an already tenuous globular mass.
A very uncommon circumstance in its development was that it lost all trace of tail previous to its arrival at perihelion on the 16th of November.
But the ethereal substance long supposed to obstruct the movement of Encke's comet would there be nearly 2,000 times denser than at the perihelion of the smaller body, and must have exerted a conspicuous retarding influence.
Newcomb finds the anomalous motion of the perihelion to be even larger (43" instead of 38") than Leverrier made it.
The diagram represents the ellipse supposed to be described, E being the orbit of the earth, M that of Mercury, and N that of the assumed nebula, its aphelion distance being about 95 millions of miles, and the perihelion 24 millions.
Four thousand miles of butcherous heat, just to have some joker come along, use your data and drum you out of the glory by crossing at perihelion forty-four days later?
I want to make a Crossing at perihelion and I want to cross on the surface.
That makes the Brightside of Mercury at perihelion the hottest place in the Solar System, with one single exception: the surface of the Sun itself.
They would reach a new perihelion far beyond the limits of safety.
When the summer of one hemisphere happens at perihelion and the winter at aphelion, it will be clear that the summer of the other hemisphere will happen at aphelion and its winter at perihelion.
And each year its summer point shifted a little further from perihelion round its path.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "perihelion" in a variety of sentences. We hope that you will now be able to make sentences using this word.
