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--------------------- 2453 - SOLAR SYSTEM - Mapping Solar System and our Galaxy
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- This map shows the asteroid belt between Mars and Jupiter and the Kuiper Belt beyond Neptune in chaotic detail. It shows each asteroid at its exact position on New Years' Eve 1999. This includes everything we know of that's over 6.2 miles (10 kilometers) in diameter, It includes about 10,000 asteroids , as well as 8,000 randomized objects of unknown size.
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- This is our solar system in macro. Notice that Pluto is shown inside Neptune's orbit. About 10% of the time, Pluto is actually closer to the Sun than Neptune.
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- Our celestial home is an awe-inspiring place full of stars, supernovas, nebulas, energy and dark matter, but many aspects of it remain mysterious, even to astronomers.
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- Counting stars is a tedious business. Even astronomers argue over the best way to do it. Their telescopes see only the brightest stars in our galaxy, and many of those are hidden by obscuring gas and dust.
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- One technique to estimate the stellar population of the Milky Way is to look at how fast stars are orbiting within it, which gives an indication of the gravitational pull, and therefore the mass, of the galaxy. Divide the galactic mass by the average size of a star and you should have your answer.
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- But, these numbers are all approximations. Stars vary widely in size, and many assumptions go into estimating the number of stars residing in the Milky Way so perhaps the Milky Way contains about 100,000,000,000 stars.
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- Astronomers are still unsure exactly how much our galaxy weighs, with estimates ranging from 700 billion to 2 trillion times the mass of our Sun. Most of the Milky Way's mass, perhaps 85 percent , is in the form of dark matter which we can not observe. The estimate of the Milky Way's mass to 960,000,000,000 times the mass of the Sun,
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- The large-scale structure of the universe looks like a colossal cosmic web, with string-like filaments connecting dense regions separated by enormous, mostly empty voids.
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- Lurking in the heart of our galaxy is a gigantic black hole with the weight of 4 million suns. Scientists know that it's there because they can trace the paths of stars in the Milky Way's center and see that they seem to orbit a super massive object that can't be seen.
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- Astronomers have been combining observations from multiple radio telescopes to try and get a glimpse of the environment surrounding the blackhole, which is packed with gas and dust spinning around the blackhole's center.
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- Also swirling through the mostly empty space between the stars in our galaxy is a bunch of dirty grease. Oily organic molecules known as aliphatic carbon compounds that are produced in certain types of stars and then are leaked out into interstellar space.
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- A recent study found that these grease-like substances could account for between a quarter and one-half of the Milky Way's interstellar carbon. Because carbon is an essential building block of living things, finding it in abundance throughout the galaxy could suggest that other star systems harbor life.
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- Our galaxy is currently speeding toward our neighbor, the Andromeda galaxy, at around 250,000 miles per hour. When the crash comes, in about 4,000,000,000 years, the massive Andromeda galaxy would swallow up our own Milky Way. Andromeda weighs about 800,000,000,000 suns, or about the same as the Milky Way's mass.
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- Astronomers have discovered gigantic, never-before-seen structures stretching for 25,000 light-years above and below the Milky Way galaxy. Named 'Fermi bubbles' after the telescope that found them, these gamma-ray-emitting objects have defied astronomers' explanations ever since.
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- Evidence is suggesting that these bubbles are the aftermath of an energetic event 6 million to 9 million years ago, when the super massive blackhole in the galactic center swallowed a huge clump of gas and dust and burped out the giant, glowing clouds.
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- Over the last decade, astronomers have also been detecting odd flashes of light coming at them from the distant cosmos. Known as fast radio bursts (FRBs), these mysterious signals have no agreed-upon explanation.
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- To date over 50 FRB’s have been detected. We still don't know the odd flashes' origin. Their light has traveled through several billion light-years of gas and dust to reach us.
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- What else is out there waiting to be discovered? The more we learn the more we learn there is more to learn.
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- October 19, 2019. 2453
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--------------------- Saturday, October 19, 2019 -------------------------
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