Re: [PLUG] "Nearby"

[christopher barry <christopher.r.barry@gmail.com>]

Fantastic writeup - Thanks!

On Fri, 24 Feb 2017 12:56:10 -0500
Timothy Jones <ti.do.jo@gmail.com> wrote:

> It is moving about 56 km/s toward us (thought not necessarily directly
> towards us, just that the distance between that star and our star is
> shrinking by 56 km/s). But don't get your hopes up.
> 
> The planets are probably tidally locked or near tidally locked and
> suffer run-away
> green house effects <https://arxiv.org/abs/1602.05176>; also they are
> incredibly close to their star so they would need some very serious
> ozone protection or else life would probably be limited to deep
> oceans if they had oceans that hadn't boiled away or frozen over.
> They may possibly have lost their atmospheres due to being so close
> to the star.
> 
> Even for the moons in our solar system, though, when the ocean is
> frozen over, there is a suspected liquid layer underneath that could
> possible host life (e.g. Europa) which is why NASA has an interest in
> looking for potential life on Europa. So the conditions of the
> TRAPPIST-1 system may support some form of life but like with Europa,
> the ability for complex life to develop is highly limited due to lack
> of resources. Also, life can be fragile, and Earth went through many
> periods of mass extinctions; if any of the planets around TRAPPIST-1
> have life, they are probably relegated to small regions in the
> twilight zones (that is, if one side always faces the star and the
> other always faces empty space, the part of the planet between these
> two zones would be in permanent twilight and have the mildest
> climates if the planets still have their atmospheres) making life on
> those planets much more vulnerable to total extinction, a fate Earth
> avoided in part due to being almost entirely habitable and thus
> having a more diverse biosphere.
> 
> Two things are interesting about our findings on exoplanets: it is
> pretty common for a star to have planets (just a few decades ago this
> wasn't an accepted reality); and our solar system seems to be a bit
> of an outlier in terms of the configuration of planets around the
> star. A lot of these systems have Jupiter size or larger planets in
> very close orbit around the star; in the case of TRAPPIST-1, the star
> is much much weaker than the sun and all the planets we've found are
> in a very close tight orbit. This later fact may be due to selection
> bias, i.e. it is easier to find planets around a star when the
> planets are large and very close because the motion of the star is
> more strongly affected (for Doppler-effect discovered planets and
> also the luminosity detection method) and also when they are closer
> to the star and the plane of orbit is nearly head on relative to
> Earth.
> 
> That being said, 40 lightyears is a long way away. Apollo 10's max
> speed was around 11082.5 m/s which is the fastest manned craft speed
> we've ever obtained. That's slower than how fast TRAPPIST-1 is moving
> toward us! 40 light years is 3.784e+17 meters away. If Apollo 10 went
> directly towards the start, it would close the distance at a rate of
> about 67082.5 m/s. It would take Apollo 10 approximately
> 5.6408154e+12 seconds to make it to TRAPPIST-1. That's nearly 178,846
> years. Rocket technology hasn't changed too much since then. Our
> national debt is nearly 20 trillion dollars. China has massive
> internal debt as well. India still has massive poverty. Russia
> doesn't have a large enough economy. Even if the entire world turned
> all of their defense spending towards producing a generational ship
> to reach TRAPPIST-1, we are still talking many tens of thousands of
> years at best, ignoring all threats to human life such as radiation,
> collision with stray objects, etc. It just won't happen with our
> current technology and there are no foreseeable advancements that
> would make this happen any sooner.
> 
> Science fiction has sparked our imagination of traveling to the stars
> but the cold reality is that while there is probably a lot of life
> off Earth in this Universe, everybody is trapped in their own solar
> systems by relativity and the vast distances between stars. Also,
> Earth is about 4.5 billion years old and we have about another 5
> billion years until our sun eats its inner planets. So who knows what
> can happen in those five billion years. But just keep in mind that
> human-level intelligence is probably very rare in any case. Some
> scientist have proposed that at one point about 75,000 years ago the
> human species was once reduced to 3,000 - 10,000 individuals due to
> climate catastrophes. We were so close to extinction we could
> probably taste it. Earth was very close to losing its human
> population, in which case today it would be a wild planet whose
> greatest intelligence might be the non-human apes that survive today.
> Not only must a planet have the right conditions for life, it must
> also have the right conditions for complex life, and even then, its
> going to take some luck to get to a human-like species.
> 
> So we are probably not alone but we are also probably very, very
> rare, and we likely won't meet any alien intelligence before we go
> extinct. Sorry bout it.
> 
> https://en.wikipedia.org/wiki/TRAPPIST-1
> 
> On Thu, Feb 23, 2017 at 11:06 AM, Paul Walker <pjwalker76@gmail.com>
> wrote:
> 
> > I wonder what the relative motion of this newly identified system
> > and our solar system is. Are the systems moving towards or away
> > from each other, or will they maintain the same relative distance
> > over the next several hundred years?
> >
> > On Thu, Feb 23, 2017 at 1:11 AM, Rich Mingin (PLUG) <plug@frags.us>
> > wrote: 
> >> None of those obstacle are insurmountable.
> >>
> >> On Thu, Feb 23, 2017 at 12:08 AM, Joe Rosato <rosatoj@gmail.com>
> >> wrote: 
> >>> Rich,
> >>> Travel time
> >>> (https://en.wikipedia.org/wiki/Interstellar_travel#Trav el_time)
> >>>
> >>> An interstellar ship would face manifold hazards found in
> >>> interplanetary travel
> >>> <https://en.wikipedia.org/wiki/Interplanetary_travel>, including
> >>> vacuum <https://en.wikipedia.org/wiki/Vacuum>, radiation
> >>> <https://en.wikipedia.org/wiki/Ionizing_radiation>,
> >>> weightlessness <https://en.wikipedia.org/wiki/Weightlessness>,
> >>> and micrometeoroids
> >>> <https://en.wikipedia.org/wiki/Micrometeoroid>. Even the minimum
> >>> multi-year travel times to the nearest stars are beyond current
> >>> manned space mission design experience.
> >>>
> >>> Joe
> >>>
> >>> On Wed, Feb 22, 2017 at 6:37 PM Rich Mingin (PLUG) <plug@frags.us>
> >>> wrote:
> >>>  
> >>>> Respectfully, you're wrong, Joe. We could leave NOW (well, minus
> >>>> construction time) if we really wanted to. We've had the
> >>>> technology to make a 40ly trip for decades. It's just so
> >>>> expensive as to *seem* impossible.
> >>>>
> >>>> The limiters are the inefficiency of our recycling, and the lack
> >>>> of collective will.
> >>>>
> >>>> On Wed, Feb 22, 2017 at 5:13 PM, Joe Rosato <rosatoj@gmail.com>
> >>>> wrote:
> >>>>
> >>>> Considering "2001 a space odyssey" had us going on a manned
> >>>> Jupiter flight with HAL (missed by 16 years at this point), and
> >>>> BladeRunner with flying cars that park on top and inside
> >>>> buildings in 2019 (hurry up!!) - I think our Sci-Fi to reality
> >>>> gauge needs to be re-tuned.
> >>>>
> >>>> I pretty sure that we will be waiting a long time before we can
> >>>> travel 40 light years.
> >>>>
> >>>>
> >>>> On Wed, Feb 22, 2017 at 4:07 PM Ronald P Guilmet
> >>>> <ronpguilmet@gmail.com> wrote:
> >>>>
> >>>> Given that the sun's lifespan is half over where do you think
> >>>> space exploration is headed? Are we, humans, looking for a place
> >>>> to colonize before it all goes black? I always wonder that.
> >>>>
> >>>> On Feb 22, 2017 3:46 PM, "jeff" <jeffv@op.net> wrote:
> >>>>
> >>>> Kelly Johnson - Skunkworks
> >>>> "We have the technology to send ET home."
> >>>> ____________________________________________________________

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