Galaxies
The cold and vast vacuum, the everlasting night of intergalactic space, is a place so desolate that, by comparison, planets and stars and galaxies seem achingly rare and lovely.
Before us is the Cosmos on the grandest scale we know. We are in the realm of the nebulae, eight billion light-years from Earth, halfway to the edge of the known universe.
From an intergalactic vantage point we would see, strewn like sea froth on the wave of cosmos, innumerable faint, wispy tendrils of light. These are galaxies. There are some hundred billion or more galaxies, each with, on average, a hundred billion stars.
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| A galaxy reminds me more of a collection of lovely found objects – seashells, perhaps, or corals, the productions of Nature laboring for aeons in the cosmic ocean. Image: © Megan Jorgensen (Elena) |
Some galaxies are solitary wanderers, most inhabit communal clusters, huddling together, drifting endlessly in the great cosmic dark.
Within a galaxy are stars and worlds and, it may be, a proliferation of living things and intelligent beings and spacefaring civilisations
The unstructured blubs of irregular galaxies, the arms of spiral galaxies an the torus of ring galaxies exist for only a few frames in the cosmic motion picture, the dissipate, often to be reformed again.
Our sense of galaxies as ponderous rigid bodies is mistaken. They are fluid structures with 100 billion stellar components. Just as a human being, a collection of 100 trillion cells, is typically in a steady state between synthesis and decay and is more than the sum of its parts, so also is a galaxy.
The suicide rate among galaxies is high. Some nearby examples, tens of hundreds of millions of light-years away, are powerful sources of X-rays, infrared radiation and radio waves, have extremely luminous cores and fluctuate in brightness on time scales of weeks. Some display jets of radiation, thousand-light-year-long plumes, and disks of dust in substantial disarray. These galaxies are blowing themselves up.
Black holes ranging from millions of billions of times more massive than the Sun are suspected in the cores of giant elliptical galaxies such as NGC 6251 and M87. There is something very massive, very dense, and very small ticking and purring inside M87 – from a region smaller than the solar system. A black hole is implicated. Billions of light-years away are still more tumultuous objects, the quasars, which may be the colossal explosions of young galaxies, the mightiest events in the history of the universe since the Big Bang itself.
Suicide Rate Among Galaxies
The unstructured blubs of irregular galaxies, the arms of spiral galaxies an the torus of ring galaxies exist for only a few frames in the cosmic motion picture, the dissipate, often to be reformed again.
Our sense of galaxies as ponderous rigid bodies is mistaken. They are fluid structures with 100 billion stellar components. Just as a human being, a collection of 100 trillion cells, is typically in a steady state between synthesis and decay and is more than the sum of its parts, so also is a galaxy.
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| Must we devise ingenious and intricate methods to aid the Earthlings to escape from the Earth, their cradle? (Quotations from Megan Jorgenson). Red Diffraction. Image by © M. Jorgenson (Elena) |
Black holes ranging from millions of billions of times more massive than the Sun are suspected in the cores of giant elliptical galaxies such as NGC 6251 and M87. There is something very massive, very dense, and very small ticking and purring inside M87 – from a region smaller than the solar system. A black hole is implicated. Billions of light-years away are still more tumultuous objects, the quasars, which may be the colossal explosions of young galaxies, the mightiest events in the history of the universe since the Big Bang itself.
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