The United States is on the verge of making a profound strategic mistake. The nation is preparing to spend $85 billion replacing working nuclear-armed Minuteman intercontinental ballistic missiles with a new "Ground Based Strategic Deterrent." Like the old missiles, the new arsenal will consist of silo-based rockets with nuclear warheads.
This vast expenditure will make the nation's strategic deterrent exactly as overwhelming as it is today. It will have zero utility in any war the United States is likely to fight and survive. It will increase the national debt with no corresponding increase in economic productivity to pay off that debt. The $85 billion estimate assumes no cost overruns, or technological or logistical problems along the way.
Other things to check out:
There's No Place Like Home (in Our Own Solar System): Searching for ET Near White Dwarfs -
It is argued in this paper that migration of an entire biological population or even a small part of a population is virtually impossible, but in any event, far more difficult than remaining in one's home solar system where the problem of continued survival can best be solved. This leads to the conclusion that sub-giants, red giants, planetary nebula, and white dwarfs are the best possible candidate targets for SETI observations. Search strategies are suggested.
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Comments: 22 pages, 0 figures, accepted for publication in the Journal of the British Interplanetary Society (JBIS), comments welcome
Subjects: Popular Physics (physics.pop-ph); Earth and Planetary Astrophysics (astro-ph.EP)
Cite as: arXiv:2001.00673 [physics.pop-ph] (or arXiv:2001.00673v1 [physics.pop-ph] for this version)
Submission history
From: John Gertz
[v1] Fri, 3 Jan 2020 00:16:56 UTC (902 KB)
https://arxiv.org/abs/2001.00673
Astrobiology
What is the asteroid belt? | Space | EarthSky
The asteroid belt is a region of our solar system – between the orbits of Mars and Jupiter – in which many small bodies orbit our sun. Here’s a good basic introduction.
Here is the inner part of our solar system, from the sun to the 5th planet, Jupiter. In this illustration, the asteroid belt is the white donut-shaped cloud. Image via Wikimedia Commons .
Meet the asteroid belt, a place in our solar system where small bodies – mostly rocky and some metallic – orbit the sun. These little worlds are also sometimes called minor planets . They move mostly between the orbits of the fourth planet Mars and fifth planet Jupiter. Astronomers once thought they were all that was left of a rocky planet, long ago torn apart by Jupiter's gravity.
It's A Big Year For The Solar System As Mars, Saturn, Jupiter And Venus Take Turns To Look Their
Images of the planets in our solar system taken by NASA spacecraft are grouped together to show ... [+] (from top to bottom) Mercury, Venus, Earth and its moon, Mars, Jupiter, Saturn, Uranus, and Neptune.
If you've never seen one of the solar system's outer planets shine brightly in the night sky, 2020 is the year to get yourself a small telescope. Here's why:
Three planets will reach "opposition" (when Earth passes between it and the Sun) and shine extra-bright: Mars, Saturn and Jupiter It's a "year of Venus" since the inner planet is a bright object in the west after sunset for most of the first half of 2020. Consequently, it will often be seen close to a crescent Moon in the post-sunset sky. There will be a lot of focus on Mars as four spacecraft launch this coming summer.
While you're here, how about this:
"Super-Puff" Exoplanets Aren't Like Anything We've Got in the Solar System -
The study of extrasolar planets has really exploded in recent years. Currently, astronomers have been able to confirm the existence of 4,104 planets beyond our Solar System, with another 4900 awaiting confirmation. The study of these many planets has revealed things about the range of possible planets in our Universe and taught us that there are many for which there are no analogs in our Solar System.
For example, thanks to new data obtained by the Hubble Space Telescope , astronomers have learned more about a new class of exoplanet known as " super-puff " planets. Planets in this class are essentially young gas giants that are comparable in size to Jupiter but have masses that are just a few times greater than that of Earth. This results in their atmospheres having the density of cotton candy, hence the delightful nickname!
Scientist figures out how to move our sun to avoid space collisions - Big Think
Advancing space travel generally involves building more powerful and efficient engines for space vehicles like rockets or shuttles. But what if instead of an individual spacecraft, you took our whole solar system on a ride through the galaxy by moving the sun? Such is the not-too-modest proposal of nuclear astrophysicist Matthew Caplan from Illinois State University. He published his designs for stellar engines in the December 2019 issue of the peer-reviewed journal Acta Astronautica.
Mercury's outer layers may have been stripped off by a young Venus | New Scientist
NASA/Johns Hopkins University Applied Physics Laboratory/Arizona State University/Carnegie Institution of Washington. Image reproduced courtesy of Science/AAAS.
Mercury may have been robbed by Venus in the early days of the solar system. A series of close passes between the two planets when they were young could have stripped away Mercury's outer layers, leaving behind a world that is mostly dense core.
Mercury's iron core makes up 70 per cent of its mass, a much higher proportion than any other rocky planet in the solar system. To end up like this, something must …
Solar panels — Should you buy, lease or subscribe? - Chicago Sun-Times
That mix of incentives has led to a surge in interest among homeowners who want to add solar arrays and batteries to their homes, and the companies offering those packages have noticed. Sunrun, which sells solar panels primarily through long-term lease agreements, in October saw traffic spike 1500% to the page on its website which explains how to power through blackouts, shortly after Pacific Gas & Electric cut power proactively to thousands of people hoping to prevent wildfires.
"Interest has by far gone through the roof," said Evelyn Huang, chief customer experience officer at Sunrun.
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