
Seven earth-sized planets discovered circling a star 39 light years from Earth - ngoldbaum
http://www.nature.com/news/these-seven-alien-worlds-could-help-explain-how-planets-form-1.21512?WT.mc_id=TWT_NatureNews
======
dmix
My favourite part of the press release:

> The planets also are very close to each other. If a person was standing on
> one of the planet’s surface, they could gaze up and potentially see
> geological features or clouds of neighboring worlds, which would sometimes
> appear larger than the moon in Earth's sky.

> In contrast to our sun, the TRAPPIST-1 star – classified as an ultra-cool
> dwarf – is so cool that liquid water could survive on planets orbiting very
> close to it, closer than is possible on planets in our solar system. All
> seven of the TRAPPIST-1 planetary orbits are closer to their host star than
> Mercury is to our sun.

[https://www.nasa.gov/press-release/nasa-telescope-reveals-
la...](https://www.nasa.gov/press-release/nasa-telescope-reveals-largest-
batch-of-earth-size-habitable-zone-planets-around/)

~~~
dcposch
> The planets also are very close to each other. If a person was standing on
> one of the planet’s surface, they could gaze up and potentially see
> geological features or clouds of neighboring worlds, which would sometimes
> appear larger than the moon in Earth's sky.

this reminds me of one my favorite films ever. it is just four minutes long

[http://www.erikwernquist.com/wanderers/](http://www.erikwernquist.com/wanderers/)

~~~
jimmaswell
If you liked this, you'll probably also like MelodySheep's Symphony of Science
series.

[https://www.youtube.com/watch?v=zSgiXGELjbc](https://www.youtube.com/watch?v=zSgiXGELjbc)

~~~
iamjeff
This brought me to tears, literally... There is a beauty to the words that is
hard to describe other than to say it gives "meaning" (for lack of a better
word) to life on this rock.

~~~
jimmaswell
Another good video is Sagan's "Pale Blue Dot"
[https://www.youtube.com/watch?v=4PN5JJDh78I&feature=youtu.be](https://www.youtube.com/watch?v=4PN5JJDh78I&feature=youtu.be)

------
e0m
To get a spacecraft there it would take:

Accelerating at 1g the 1st half, and decelerating at 1g the 2nd half, the
traveler would experience 7.3 years of time. For observers it would take 41.8
years at a max speed of 0.998c

If you had a near perfect hydrogen -> helium fusion engine, it'd take about 6
million tons of fuel (about the mass of the Pyramids of Egypt or 2,000 Saturn
V rockets)

~~~
kcorbitt
That actually sounds... more plausible than I would have expected. Like,
doable with technology I can imagine being within reach in the next 50 years
even if we don't achieve any currently-unforseen breakthroughs.

~~~
blueprint
Which begs the question, why haven't we at least even tried to have done
anything like this already?

Do we really need to repeatedly spend comparable amounts of money on yet
another dramatic TV special about humans traveling to Mars, as narrated by a
favored celebrity? We really are running out of time. And it almost seems like
it's pre-determined to happen. :\

~~~
Balgair
The engineering issues are really tough, though surmountable. Currently, we
just can't engineer the parts that will last that long in hard vacuum. Mostly
because we can't test in that environment easily. Also, what do you do when
all the light bulbs have burned out or gone haywire, what does that fault-tree
look like for the billion and one parts on the craft? For a short journey of
~7 years, it's not a very big deal, it's just engineering issues. When you get
into generation ship discussions then it becomes a human rights nightmare to
trap newborns in a ship for their entire life and the lives of their
descendants.

~~~
blueprint
Yeah I'm to be honest just trying to awaken people to the priority being that
we need to establish a self-sufficient colony somewhere other than Earth.

~~~
rocqua
Honestly, as long as humans stay stuck to earth, losing all humanity on earth
won't hurt anyone. As long as the extinction is instant. If we have colonies,
those colonies need to suffer through the knowledge that we lost earth.

Establishing colonies is only imperative if the continuation of the human race
is. I'd argue that humans have value only due to other humans. There is
nothing inherently valuable about human life from a non-human perspective.

That is not to say I don't support space colonization, just that I don't think
its a moral imperative.

~~~
jacobush
"There is nothing inherently valuable about human life from a non-human
perspective."

How would you know?

~~~
nkrisc
It's a perfectly reasonable assumption until there's some evidence there is.
Given the vastness and scale of the universe, it seems quite likely that our
disappearance would never be noticed.

~~~
jacobush
Going unnoticed is not the same as inherently not valuable. Imagine aliens
finding us extinct, wringing their little tentacles in dispair at the lost
probing opportunities. :)

------
callumprentice
A few months ago, I made a simple WebGL app to compare the sizes of our sun
and the planets for my 5 year old daughter who was curious. I updated it today
to include the TRAPPIST system and see how it compares to our own solar
system.

[http://callumprentice.github.io/apps/celestial_bodies/index....](http://callumprentice.github.io/apps/celestial_bodies/index.html?1=earth&2=trappist-b)

~~~
callumprentice
Thanks for the nice feedback everyone. I had some time tonight after work and
made an improved version with better selection UI and allows for multiple
bodies at once:
[http://callumprentice.github.io/apps/celestial_bodies/index....](http://callumprentice.github.io/apps/celestial_bodies/index.html?v=2&1=trappist-1&2=trappist-1b&3=trappist-1c&4=trappist-1d&5=trappist-1e&6=trappist-1f&7=trappist-1g&8=trappist-1h&9=earth)

------
cletusw
Apparently finds are close enough to us that we should be able "to follow up,
to see, for example with the James Webb Space Telescope that we're going to
launch [next] year, the atmospheres and also to look at bio-signatures, if
there are any" !

~~~
kitrose
Can someone explain to me why we don't replicate some of these key platforms
like the Hubble and James Webb ST?

It seems like the major limitation for discovery is getting enough observation
time for whatever certain point in the sky that scientists are researching.

Why don't we launch a second copy of James Webb?

~~~
RileyJames
It looks like the James Webb cost $8.7B to launch. The Hubble $4.7B at launch
and $10B through till 2010. So it seems cost is the limiting factor. Replicas
might be cheaper, but they wouldn't be kickstarter cheap.

~~~
settsu
In an attempt to avoid the appearance of politicking, I'd offer that this is
not as significant a sum as it may seem initially, viewed in relative terms
to... other governmental expenditures.

~~~
mememachine
You should remember that youre not the only one trying to take and spend tax
money.

------
echelon
I imagine any intelligent life that evolves on a system with so many planets
in such close proximity--many within the habitable zone, and each perhaps with
atmospheres and organics--will have a much easier time than we do of pushing
forward to becoming a multi-planetary species.

We lucked out with Earth being as hospitable and resource rich as it is, but
we're stuck in a deep gravity well with not much in our solar system to compel
us to leave. That puts us at a relative disadvantage to other alien species
that have the benefit of cheap and interesting neighbors to visit.

I'm jealous to dream of what could have been had we evolved in a differently
configured solar system.

~~~
bbarn
..and what problems we don't have they might have!

Planets too close, disrupting each other's ecosystems. The usable ice being
distributed amongst several planets when the system was formed instead of a
single one.. there's no end to catastrophic possibilities.

This is why I still love sci-fi. Anything you can think of, put it on paper,
and it could make for a great story.

~~~
alex_duf
Not to mention the whole "us" and "them" separation that would eventually
arise the same way we have with our arbitrary borders.

Hmm, wait we were talking about intelligent species, never-mind.

------
6502nerdface
> Gillon says that the six inner planets probably formed farther away from
> their star and then migrated inward. Now, they are so close to each other
> that their gravitational fields interact, nudging one another in ways that
> enabled the team to estimate each planet's mass. They range from around 0.4
> to 1.4 times the mass of the Earth.

Given that these planets are so close to each other, and interacting with each
other gravitationally, how likely is it that their orbital arrangement is
stable over geological time?

~~~
mturmon
According to the _Nature_ paper (last section of
[http://www.nature.com/nature/journal/v542/n7642/full/nature2...](http://www.nature.com/nature/journal/v542/n7642/full/nature21360.html))
--

We computed [via n-body and other simulations] that TRAPPIST-1 has a 25%
chance of suffering an instability over 1 Myr, and an 8.1% chance of surviving
for 1 billion years (Gyr), in line with our n-body integrations.

And, further,

However, [these lifetimes] do not take into account the proximity of the
planets to their host star and the resulting strong tidal effects that might
act to stabilize the system. ... The masses and exact eccentricities of the
planets remain uncertain, and our results make it likely that only a very
small number of orbital configurations lead to stable configurations. ... The
system clearly exists, and it is unlikely that we are observing it just before
its catastrophic disruption, so it is probably stable over a long timescale.
These facts and the results of our dynamical simulations indicate that, given
enough data, the very existence of the system should bring strong constraints
on its components’ properties...

------
jobu
The article mentions the star being an ultra-cool dwarf star, but doesn't give
an explanation of what that means. Here's some info from Wikipedia that I
found useful:

 _TRAPPIST-1 is an ultracool dwarf star that is approximately 8% the mass of
and 11% the radius of the Sun. It has a temperature of 2550 K and is at least
500 million years old. In comparison, the Sun is about 4.6 billion years old
and has a temperature of 5778 K._

 _Due to its mass, the star has the ability to live for up to 4–5 trillion
years ..._

[https://en.wikipedia.org/wiki/TRAPPIST-1](https://en.wikipedia.org/wiki/TRAPPIST-1)

------
r721
Wiki says "TRAPPIST-1 is an ultracool dwarf star that is approximately 8% the
mass of and 11% the radius of the Sun. It has a temperature of 2550 K and is
at least 500 million years old."

[https://en.wikipedia.org/wiki/TRAPPIST-1](https://en.wikipedia.org/wiki/TRAPPIST-1)

Too young star for alien life hopes?

~~~
dwaltrip
In the Q&A session they said it's difficult to constrain the age of the long-
lived ultraviolet dwarf stars once they finish the active early phase, as
their lifecycle progresses so slowly. They live for more than a trillion
years, compared to stars like our sun which are larger and burn through their
fuel in less than 10 billion years.

It's somewhat counterintuitive, but the bigger a star is, the faster it uses
up its fuel, despite having much more of it. As size increases, the rate of
fusion in the star's core increases such that the extra fuel isn't enough to
prevent the lifespan from shortening. In fact, a common type of supernova
occurs in stars that are at least 8 times the size of the sun, burn through
their fuel in less than 100 million years, and then go out in style.

Crash course astronomy has some great videos on this stuff:
[https://youtu.be/PWx9DurgPn8](https://youtu.be/PWx9DurgPn8)

~~~
JumpCrisscross
> _it 's difficult to constrain the life of the long-lived ultraviolet dwarf
> stars_

What's the upper bound on their estimate for TRAPIST-1's age?

~~~
biot
The upper bound is the age of the universe.

~~~
perlgeek
This may sound a bit snarky, but it's actually quite a good boundary.

Current estimations for the age of the Universe are around 12 to 14 billion
years, which isn't much compared to a trillion year life span of such a star.

~~~
ianai
Plot twist: It's actually 2 trillion years old. Everything we know of the
universe is wrong! (I'd bet I'm not the only one who'd find that a more
interesting option.)

------
cletus
So this star is essentially going to live forever from what I understand (ie
trillions of years). It's cool and the habitable zone is close to the star.

So I know nothing about this kind of star but I was reading something last
year talking about risks to life. There's of course the obvious like being hit
by comets and asteroids, gamma ray bursts and so on.

But there's also CMEs (coronal mass ejections). A CME from the Sun directly
hitting the Earth would be devastating. The chance of getting hit by a CME is
inversely proportional to your distance from the star just because you occupy
a smaller arc from the star's perspective.

I wonder if this kind of star and having the worlds so close would pose a huge
threat from CMEs. Does this kind of star even have the same number of CMEs as
say the Sun?

------
webmaven
Hah, called it:
[https://news.ycombinator.com/item?id=13698672](https://news.ycombinator.com/item?id=13698672)

------
rlanday
Now technically, according to the International Astronomical Union, these
bodies can't be planets since they don't orbit the sun:
[https://www.iau.org/static/resolutions/Resolution_GA26-5-6.p...](https://www.iau.org/static/resolutions/Resolution_GA26-5-6.pdf)

"1\. A planet is a celestial body that (a) is in orbit around the Sun"

Makes me wonder how much this definition of a planet was motivated by the
desire to be able to give elementary schoolers a nice small set of things to
memorize.

Edit: actually I might be incorrect about this, the resolution is titled
"Definition of a Planet in the Solar System", I'm not sure the IAU actually
has a definition of what a "planet" would be outside the solar system, but
they may be open to the idea that they exist :)

~~~
hughes
Are you saying that they don't orbit their star because some of them
gravitationally influence each other?

Or are you saying that nothing outside of our solar system can be a planet?

Either way, NASA should schedule another press release about taking celestial
pedantry to a new level.

~~~
rlanday
My understanding is that according to the IAU definition, a "planet" must
orbit the sun and not any other star. Kind of reminds me of when people
thought the solar system was the center of the universe.

~~~
acqq
The word planet comes from the ancient Greek word for "wanderer" which they
used to refer to the wandering stars, the only stars that moved across the sky
in relation the all other stars, only five of them visible, assigned to the
gods and one goddess: Hermes, Aphrodite, Ares, Zeus and Cronus. Since then,
the definition of the planet had to be modified as there are a lot of bodies
orbiting the Sun known today. According to the latest precise definition, even
Pluto isn't a planet anymore (but a dwarf planet).

In this light, I don't see the problem in making the difference between the
planets (orbiting our Sun) and the exoplanets (orbiting other stars, see my
other post here).

These guys however would like to remove the International Astronomical Union's
definition from 2006 and to introduce the new with which even the moons(!) of
the planets would be called "planets":

[https://arstechnica.com/science/2017/02/how-positively-
peeve...](https://arstechnica.com/science/2017/02/how-positively-peeved-pluto-
people-plan-to-pluck-back-plutos-planethood/)

As the reporter cleverly summarized, their definition could be simpler stated
as, "round objects in space that are smaller than stars." Then there would be
around 110 such "planets" around the Sun, and the exoplanets would also be, of
course, just "planets."

Their reasoning:

"In the mind of the public, the word “planet” carries a significance lacking
in other words used to describe planetary bodies. In the decade following the
supposed “demotion” of Pluto by the International Astronomical Union (IAU)
[1], many members of the public, in our experience, assume that alleged “non-
planets” cease to be interesting enough to warrant scientific exploration,
though the IAU did not intend this consequence [1]. To wit: a common question
we receive is, “Why did you send New Horizons to Pluto if it’s not a planet
anymore?” To mitigate this unfortunate perception, we propose a new definition
of planet, which has historical precedence [e.g., 2,3]. In keeping with both
sound scientific classification and peoples’ intuition, we propose a
geophysically-based definition of “planet” that importantly emphasizes a
body’s intrinsic physical properties over its extrinsic orbital properties."

------
petrikapu
Three of those discovered planets are in habitable zone

[https://www.dropbox.com/s/bdeog7ta7i4rb7c/alien%20planets.pn...](https://www.dropbox.com/s/bdeog7ta7i4rb7c/alien%20planets.png?raw=1)

~~~
jff
Are you basing that statement purely on the appearance of the planets in the
artist's conception you linked, or was it stated in another article somewhere?

~~~
cgriswald
It was stated by the scientists at the NASA press release. They also stated
that all seven of the planets have the potential for liquid water depending on
(unspecified) circumstances.

~~~
jff
Awesome, thank you.

------
sizzzzlerz
Once again, the universe shows that not only is it strange, it's stranger in
ways we can't possibly imagine. This is truly a golden age of space science
and, as Kay said in M.I.B., "I wonder what we'll know tomorrow.".

------
tuyguntn
Every time I hear such news, I try to imagine how it feels being there,
billions of miles away, looking at sky and saying "wow", I don't think we will
be able to travel to distant planets in our lifetime, but thinking about it
and trying to create that feeling always feels amazing to me.

~~~
31reasons
If we use what we know about it and recreate the system in VR we could
technically experience at least the visuals of being there.

------
eb0la
At Voyager-I speed (17km/s) we need _just_ 688k years to get there. Not bad
considering the humble satelite doesn't accelerate anymore.

~~~
mtgx
I doubt we'll attempt serious inter-stellar travel before we figure out
antimatter or black hole-powered engines. So we may have to wait a century or
two.

This century we should be more worried about making fusion-powered intra-solar
system travel a common thing, and about establishing large colonies on Mars
and several moons.

~~~
kakarot
I don't know about all of that speculation, but you did give me a nice mental
image of a barren, battle-scarred solar system littered with battleships
containing black holes, ready to cause catastrophe at any moment, much like
the nuclear wastelands of the Arctic.

~~~
SapphireSun
The black hole engines he's referring to glow very hot because they're very
small, meaning that the surface of the hole is large compared with its volume.
This allows for very bright hawking radiation if I understand correctly. If
you stop feeding them they disappear within hours, years, or decades depending
on how big they are.

------
un008
Is it a good news for human?

we know if cockroach stay at their nest, we don't suppose to kill them. But if
they begin to explore their new world, i.e. Human's kitchen, then we want to
kill them all.

------
fsloth
"Due to its mass, the star has the ability to live for up to 4–5 trillion
years"

So when the rest of the universe cools off and stars start to die, Trappist
one keeps on shining and shining... We need to get there. But first, let's get
rid of our genocidal tendencies.

~~~
lutorm
It's not just that one. The vast majority of stars, by number (but not by
light), are stars like these. The universe might dim, but it won't be dark for
a long, long time.

~~~
fsloth
Yes, in all bayesian likeness this is a class of star systems that populates
the universe. Suddenly the universe does not seem so dark and foreboding
anymore.

------
cletusw
Link to live stream on YouTube (supports rewinding)
[https://www.youtube.com/watch?v=UdmHHpAsMVw](https://www.youtube.com/watch?v=UdmHHpAsMVw)

------
jonshariat
This news is very interesting but how is this different than any of the recent
planet discoveries? Anyone mind explaining the significance of this discovery
over the others?

~~~
cgriswald
1\. There are a lot of them (seven). 2\. They are all Earth sized. 3\. There
are a lot of them in the habitable zone (three). 4\. Even those not in the
habitable zone could contain liquid water under certain circumstances. 5\.
This star is insanely close-by (39 ly).

Basically, if you're looking for a second Earth, this is an incredible gift.
Even if we don't find a second Earth among these seven planets, they could
tell us a lot about the likelihood of life around red dwarf stars, which is
significant, because the vast majority of stars are red dwarfs. That's in
addition to the information they can probably provide on planet formation and
makeup.

------
ant6n
It seems that this could be an interesting system to be targeted by a FOCAL
mission. It is the idea to use the sun as a large telescope by using its
gravitational sense. One would have to have a telescope placed about 550 AU or
so away from the sun, on the opposite side of the system you want to look at.

The magnification could be large enough to analyze features on exoplanets. My
dream would be to build a telescope large enough, so that with the help of the
gravitational lens of the sun we'd have a google-earth like view of the
exoplanets.

[http://www.newyorker.com/tech/elements/the-seventy-
billion-m...](http://www.newyorker.com/tech/elements/the-seventy-billion-mile-
telescope)

~~~
kk_cz
I was having hard time imaging 550 AU, so for context ( distances from the
Sun):

\- Jupiter: ~5.2 AU

\- Pluto: ~39.5 AU

\- Voyager 1 ~137,75 AU

------
scj
It'll be interesting to see this reflected in the Drake equation (average
number of planets per star that can potentially support life).

It'd be amazing if the number was above 1 (or terrible if you believe in the
Great Filter hypothesis).

------
mmaunder
Is it me or does it feel like they've extrapolated a bit too much from the
light of a star dimming at intervals?

------
rubicon33
I was reading up about earth alternatives recently, and upon realizing the
distance was always going to limit us, no matter how perfect the planet, I
realized we need to travel at the speed of light.

I think our "best shot" at that right now, is to digitize humans. If we could
store consciousness in binary, we could then transmit it at the speed of light
(like we do with data every day!). You'd need a receiver on the distant planet
though. So, your first 'payload' would have to be the receiver, and it would
need to travel the slow old fashioned way :(

~~~
twoodfin
If you're going to assume heavy equipment on the other end (ours or "someone
else's"), it's not ridiculously beyond our current capabilities to simply
transmit DNA sequences along with enough digital training material to "grow"
and raise a human population from scratch.

~~~
NegativeLatency
Not to mention the reliability and throughout requirements of such a data link
to another planet so far away.

------
coryfklein
I'm having a hard time finding more data on the density of matter in
interstellar space.

Wikipedia says

> The density of matter in the interstellar medium can vary considerably: the
> average is around 10^6 particles per m3 but cold molecular clouds can hold
> 10^8–10^12 per m3 [1]

But I imagine that interstellar gas would be easier to fly through than
interstellar sand. Do we know the composition of matter in interstellar space?

[1]
[https://en.wikipedia.org/wiki/Outer_space#Interstellar_space](https://en.wikipedia.org/wiki/Outer_space#Interstellar_space)

~~~
semaphoreP
It's almost all Hydrogen/Helium gas. Other larger atoms and molecules are
known to exist in the interstellar medium, but it's primary gas.

Also, a good way to remember the density is ~1 Hydrogen atom per cm^3.

~~~
infogulch
How about intergalactic densities?

~~~
semaphoreP
Don't know the number off the top of my head, but it should be considerably
less. It should also be highly varying as some galaxies live in pretty densely
packed environments (galaxy clusters), which some live in very open
environments like our own galaxy.

~~~
infogulch
Nothing like a little "look it up yo damn self": Looks like it's about 1
hydrogen per m^3 [1] (via SO [2]), about 1 million times less dense. Damn.

    
    
      [1]: http://www.universetoday.com/30280/intergalactic-space/
      [2]: http://physics.stackexchange.com/questions/25378/how-vacuous-is-intergalactic-space/25379#25379

------
mozumder
So, who do we call to make sure the newly discovered planets are named Chimay,
Orval, Westvleteren, Rochefort, Westmalle, Achel, and La Trappe?

~~~
iamdave
40 light years = 12.2 parsecs.

I mean I feel like an opportunity was missed here...

------
btkramer9
Even though each of the 7 planets are likely tidally locked it seems a
habitable zone on each planet is still a possibility [1]

[1] [http://nautil.us/blog/forget-earth_likewell-first-find-
alien...](http://nautil.us/blog/forget-earth_likewell-first-find-aliens-on-
eyeball-planets)

------
fsloth
I would also like to point out: Giordano Bruno was right.
[https://en.wikipedia.org/wiki/Giordano_Bruno](https://en.wikipedia.org/wiki/Giordano_Bruno)

Although, he had no proof for his intuition, so I cannot entirely cherish him
as a martyr for modern cosmology.

------
nie
When I looked at the image[1] illustrating size/mass/orbit periods of
TRAPPIST-1, I was fascinated by the orbit period:

6.10 days, for example, for planet e! Suppose we were to be able to stand on
that planet and stargaze outwards, won't that be extremely dizzy? :)

So what are the immediate (strange) properties brought forward by median of 6
days of orbit period?

[1]
[http://www.space.com/images/i/000/062/962/original/trappist-...](http://www.space.com/images/i/000/062/962/original/trappist-1-4-PIA21425-1024x576.jpg?interpolation=lanczos-
none&downsize=660:*)

~~~
alex_duf
Earth has a rotation period of 1 day (around itself). When stargazing a 1 day
rotation period would be the same as 1 day orbital period whilst being tidally
locked (which seem to be the case for these planets)

I don't think anyone is getting dizzy down here so I would assume it would be
the same there? or have I missed something?

------
Taniwha
So how come when NASA tells us there are tiny invisible planets light years
away we all applaud, but somehow when they point to the evidence of climate
change right here right now it's all a big con?

~~~
acid__
This strikes me as a rather disingenuous question.

~~~
Taniwha
why? either you think NASA is good at science or you don't, you can't pick and
choose depending on whether or not you like the results

~~~
acid__
Okay, sure. I can give you a serious answer if you'd like.

First of all, you're attempting to take down some strawman. _Who_ is
applauding this discovery, and simultaneously calling NASA's climate change
research "all a big con"? It's disingenuous when you just present a (IMHO)
off-topic opinion that the majority of the other commenters here have, in the
form of an innocent question. If you would like to discuss the view of a
public figure or other commenter, that's fine. If you want to discuss how you
think that people should accept NASA-related research as a whole or not at
all, that's fine.

But don't ask a false question to take down a strawman.

Second, your statement "either you think NASA is good at science or you don't"
is a massive trivialization. NASA is a 19 billion dollar organization, with
over 17,000 employees (not counting contractors). Beyond the problems of the
phrase "good at science" (What does it _mean_ to be "good at science"? That's
an incredibly complex topic.), NASA is huge, with many, many different people
and departments, opinions and beliefs, cultures, etc. Thinking of NASA as a
fixed, singular, cohesive entity is a flawed assumption.

And I guess finally, to get back to your original question, it's quite
straightforward. The (economic, political) implications of habitable planets
40 light years away is quite different from the (economic, political)
implications of American industrial and economic activity needing to be
massively changed, very quickly.

Don't get me wrong, I'm a firm believer that climate change is a human-caused
phenomenon. But I don't feel that your original question was presented in the
best possible way.

------
bikamonki
Ok Elon, _only_ 39 light years away. When will you take us there?

------
chiph
Home planets of the puppeteers?

[https://en.wikipedia.org/wiki/Pierson%27s_Puppeteers](https://en.wikipedia.org/wiki/Pierson%27s_Puppeteers)

------
neilellis
I wonder if SETI are going to point at it, you know, just incase :)

------
andrewclunn
They're only one Kessel Run away!

~~~
awful
Or, maybe our Zyra.

------
bcaulfield
Let's go

~~~
ionwake
It's a Trap ;)

On a serious note, if we can travel close to the speed of light , say 95%,
using for example, nuclear rockets, how long would it take to arrive ? ( from
the travellers perspective )

~~~
vkou
At a constant 1g of acceleration, you could travel there, from the traveler's
point of view, in ~2-3 years. (And in ~40 years from a stationary observer's
point of view.)

Mind you, a constant 1g acceleration (Or accelerating any human-carrying
spaceship to relativistic speeds, really,) is about as plausible as a
spaceship driven by pixie dust and unicorn farts.

~~~
ionwake
Not according to public research on theoretical designs that have been about
for decades . Unless you consider them unicorn farts! I'm only a coder though
so I have no knowledge of this domain tho. I think the problem is simply it's
too expensive to build space ships that probably won't work at all :( wasnt
NASAs budget slashed ?

~~~
twoodfin
It's not money, it's the basic rocket equation: Newtonian acceleration
requires fuel and the mass of fuel makes acceleration more costly.

Relativity makes things even worse.

~~~
ionwake
See comment above yours, does your point still apply?

~~~
dragonwriter
Absolutely.

~~~
ionwake
oh ok , you win , thanks for your replies ^_^

------
kristianc
Do we know definitively that there are no other planets in this system?

The presence of a large, Jupiter-sized planet in a system is thought to be
helpful for deflecting asteroid impacts. Obviously we are talking 'to scale'
given TRAPPIST-1 itself is around the size of Jupiter!

The more we learn about this system is going to be fascinating though - the
supposed inward migration of these planets may even help us understand more
about how our own system formed.

~~~
semaphoreP
I don't think we know for sure, but it'd be hard to place another star in the
system and have it a) not disrupt the planets and b) go unnoticed as the
primary star is so faint.

------
sigmaprimus
Based on Voyagers current speed it would take approximately 18000 years to
reach this system, the referance of a jet airplane taking millions of years
seemed a bit misleading, with current technology and using gravitational
boosting I would think that the time could be much less. Maybe it would be
worth sending a probe? Granted I will never see it in my lifetime but it might
be a project I could get behind.

~~~
pvg
18k years is a very long time, though. There is a project looking at the
feasibility of getting very small probes somewhere 10 times closer in perhaps
decades rather than millennia:

[https://www.nytimes.com/2016/04/13/science/alpha-centauri-
br...](https://www.nytimes.com/2016/04/13/science/alpha-centauri-breakthrough-
starshot-yuri-milner-stephen-hawking.html)

~~~
sigmaprimus
That is exactly what I meant, thank you for the link. I defiantly would
support projects like that.

~~~
pshposh
I suspect you meant definitely and not defiantly.

------
peterkelly
12 parsecs?

No problem, buddy. We've got the best ship in town. If you've got the dough
I'm sure me and my buddy Chewy can work something out for ya.

------
desireco42
Is this from NASA news conference that was announced for today? I couldn't
find it in article? They said they have important announcement.

~~~
castis
Yes, the exoplanet discovery was the important announcement.

------
c-smile
Therefore it appears as there are plenty of habitable planets out there.
Numbers are big enough to conclude that other life is definitely out there
somewhere so are the questions:

1\. Where are they all?

2\. How humanity will react on appearance of one of them? Will we finally stop
our fights inside that sandbox and to focus on challenges that we are facing
all together?

------
5xman
So, are there any plans to try to "communicate" with this planets? Or we are
going to just sit and watch.

~~~
TekMol
Well, we could send a message and then wait 80 years for a reply. So we might
want to work on immortality first.

~~~
5xman
I thought we were already working on immortality. On the other hand, waiting
80 years doesn't seem like much. It's not like we are going to be 'out for
lunch' if there is an answer.

------
keyle
Here is another article on it with a bit more info on the planets

[http://www.iflscience.com/space/breakthrough-in-search-
for-l...](http://www.iflscience.com/space/breakthrough-in-search-for-life-as-
seven-earthsized-worlds-found-orbiting-nearby-star/)

------
meerita
Question to HN: If you can go, knowing you cannot get back, would you go to
colonize the first planet?

------
NicoJuicy
Fun detail, the discoverers are Belgian and Trappist is a name for a monk
beer.

We Belgians sure like our beer :)

------
alnitak
Depending on how habitable those planets are, if there was an actual entity
modeling the universe _for_ humans as some close minded ideologies tend to
think, well we would be living there and not in a little blue island in the
middle of desolation. Nice blow.

------
AYBABTME
With so much proximity between worlds and seemingly easier access to nearby
space and it's resources, I feel that any sentient life in a system like this
will have had a massive evolutionary advantage over us.

------
johngalt
Close orbit around a relatively cold star. Interesting. I wonder what their
'day' vs 'year' looks like. Also their atmosphere and surface pressure. They
could be 7 copies of Venus for all we know.

~~~
imdsm
If they are tidally locked as reported, then there will be no day, not really.
Just as there is no day on the moon.

~~~
strictnein
The moon rotates once every ~27 days, so its day is ~27 days. It's just in
sync with its orbit of the earth, so it appears to us that it doesn't rotate.

[http://www.space.com/24871-does-the-moon-
rotate.html](http://www.space.com/24871-does-the-moon-rotate.html)

~~~
visakanv
Isn't that technically the moon's "year"?

~~~
idbehold
A year generally refers to the time something takes to make one revolution
around its closest star.

------
h4nkoslo
Uh oh.

The "great filter" hypothesis is essentially that the rarity of intelligent
life has to be explained by some parameter of the Drake equation, and that
whatever the "small" parameter is is either in our past or in our future.

If the "great filter" is the rarity of habitable worlds, then clearly we don't
need to fear it, since we already found one. But if habitable worlds aren't
rare, then it's more likely it lies in our future (e.g. global thermonuclear
war, plague, difficulty of space travel, etc).

Thus things like discovery of exoplanets, bacteria on mars, etc should make us
rather concerned.

[https://en.m.wikipedia.org/wiki/Great_Filter](https://en.m.wikipedia.org/wiki/Great_Filter)

~~~
root_axis
The theory as described in your link seems to hand-wave away the difficulties
incumbent in the "colonization explosion" step. As it stands, intergalactic
space travel (at scale) is utterly inconceivable in practical terms, and to
simply assume that it is inevitable seems like a major flaw in the theory.

~~~
idbehold
> then it's more likely it lies in our future (e.g. global thermonuclear war,
> plague, _difficulty of space travel_ , etc)

Difficulty of space travel is one of the possible filters.

~~~
root_axis
Ah. I guess I was responding to

> _the only thing that appears likely to keep us from [colonization explosion]
> is some sort of catastrophe or resource exhaustion leading to the
> impossibility of making the step due to consumption of the available
> resources (like for example highly constrained energy resources)._

------
libeclipse
Just for curiosities sake, using the best technology humanity could get its
hands on, what's the best case for the time it would take to reach that solar
system?

~~~
T-A
StarShot [1] is gunning for 20% of the speed of light. At that speed, it would
take a couple hundred years.

[1]
[https://breakthroughinitiatives.org/Initiative/3](https://breakthroughinitiatives.org/Initiative/3)

------
dforrestwilson1
4 separate front-page posts about this on H/N so far..

------
ausjke
Just curious, how is this related to us considering there are ziga-billion-
stars/planets not-yet-be-found in the universe, why is this news important?

~~~
ucontrol
While the system itself is nothing extraordinary from a detached, theoretical
point of view - we are aware that there are many planetary systems in the
universe of all sorts and sizes - what makes this news so impressive in my
opinion is the thrill of actually witnessing, almost tangibly, such an alien
and wonderful system, excitingly different from our own (read the article in
detail, fascinating stuff), amplified by the fact that these planets are
relatively quite close.

Basically, the system is so peculiar and close to us, now that we have
actually discovered it is difficult not to be fascinated by it, even though we
know it's nothing to be perplexed with in the grand scheme.

------
neom
My fav thing about the universe is the idea that evolution + ingredients in
another order could create something totally bizarre and wonderful!!

------
blueprint
Let's do this.

------
nepotism2016
James Webb Space Telescope is going to accelerate all of these discoveries by
x100...star KIC 8462852 is clearly aliens!!!!

------
elif
Now we just need a 40,000 generation ship.

------
staltz
Is there information already on how the short distances between planets would
affect G-forces felt on surface?

~~~
Retric
The earth moon distance is tiny, and the G-Forces are hard to directly
measure.

------
debt
That's still soo far away though.

------
sidcool
This is an exciting bit of news. 40 LY is relatively near compared to size of
our galaxy.

------
mrfusion
Have we ever detected exo moons? If not when or how might that be possible.

------
irusri
I cant understand what can we possibly achieve from this type of explorations.
NASA spends lot of money each year to excite us but nothing really achieved.
Personal thought: Isn't worthy to spend this money for alleviation of poverty
in this planet?

~~~
kk_cz
it's ~65$ per person per year. I am not American but if I were I would gladly
give 65 bucks a year for some space related excitement.

------
mkoster
Well, lets hope on these guys to take us there ;)

Apparently they are building a FTL engine.
[http://www.spacewarpdynamicsllc.com/latest-
news](http://www.spacewarpdynamicsllc.com/latest-news)

------
novalis78
Let's change #OccupyMars to #OccupyTrappist ;-)

------
vlindos
Let's bring some democracy there again!

------
huula
See? I told you that seven is a magic number.

------
jlebrech
could we send a spaceship there as a projectile rather that have (all) the
fuel on board?

------
restlessmedia
I wonder how many javascript libraries they're up to already?

~~~
bb101
That gave me a chuckle. Safe to say they would be post-React by now, but
probably still pre-SingularityJS.

------
yohann305
it's worth mentioning that the light we receiving took 39 years to arrive to
the telescope. So anything we see happened 39 years ago.

I thought it'd be nice to know...

~~~
MrZongle2
No, it's 39 light-years away.

Meaning that anything there that we can observe happened 39 years ago. Not 39
billion or billion.

~~~
ifdefdebug
Just to make sense of that reply: I remember the post was talking about 39
billion years but seemingly was edited without advice.

------
osazuwa
Firefly.

------
ahmetyas01
I knew it.

------
sperglord
raises the question

~~~
criddell
That's essentially what blueprint said. You didn't have any trouble figuring
out what blueprint was saying, right?

~~~
purple-again
What's wrong with begs the question? It's a regular part of my vocabulary and
I'm a southern American.

~~~
bryondowd
I think this article sums it up:

[http://www.quickanddirtytips.com/education/grammar/begs-
the-...](http://www.quickanddirtytips.com/education/grammar/begs-the-question-
update)

tldr: Begs the question is a formal term for when a conclusion is not
supported by given arguments. Using it the way most people do is technically
incorrect, but has become common enough that it is in the gray area where one
can consider it the new correct usage.

------
blueprint
Physicists have got blinders on. Once we solve the gravity problem everything
changes. I've been searching for a decade for scientists who can confirm my
info but tbh most everyone seems to have abandoned themselves already.

~~~
semi-extrinsic
> Once we solve the gravity problem

I have a feeling I'm going to regret asking, but here we go: what "gravity
problem"?

~~~
blueprint
You're familiar with the fact that there is no proper, substantial, accepted
model or principle of both gravity and EM that unify them, correct? And we
don't knowingly have the ability to build technology that manipulates gravity
(trivial interpretations aside). And we also don't know how our actions
actually affect the dynamic field that is gravity. Cause the stress-energy
tensor says it is dynamic. Or perhaps I'm just completely bonkers. Life
certainly would be a lot easier if I were.

~~~
Arizhel
What exactly are you saying? That once we really figure out gravity, faster-
than-light travel will become possible? I've been saying that for years, and
I'm no physicist. It's fairly obvious that gravity is not well understood by
our physics. All we really know is that it correlates to the presence of mass:
lots of mass (like a planet) equals a noticeable amount of gravity. Unlike
electromagnetism, where we have the ability to actually create it and
manipulate it at will, we have no such ability with gravity (aside from just
moving mass around, which has little effect since gravitational force is so
weak). So yeah, I've thought for a long time that understanding gravity is the
key to warp drive, just because it's such an obvious blind spot. But I'm not
sure how this is helpful; merely noticing that our understanding of gravity is
poor doesn't actually help us understand it any better.

What we need is to discover a physical effect whereby we can significantly
manipulate gravity at will. Figure that out and you'll change everything.

~~~
maverick_iceman
General relativity gives a very solid and accurate understanding of gravity.

~~~
Arizhel
It does? Great; please point me to some instructions on how to build an anti-
gravity device. I can easily build myself an electromagnet with some wire and
a battery, so if our understanding of gravity is so great, I should be able to
do the same with gravity, right?

~~~
maverick_iceman
What's your score?[1]

[1]
[http://math.ucr.edu/home/baez/crackpot.html](http://math.ucr.edu/home/baez/crackpot.html)

~~~
dang
That's a form of name-calling, which we've asked you repeatedly not to do
here. If you keep doing it, we will ban you.

------
blueprint
> The launch cost of launching the mass of the pyramids of gaza into orbit
> would bankrupt the richest economies.

Yeah… cause the way you're thinking about doing that is literally _the only
way in the world_ to accomplish the task. Not. It's not my job to qualify
whether it HAS to be done to you. And even though I am the one presenting this
information and this evidence, it is indeed your job to confirm it. Otherwise,
you're not exactly doing science, are you? Nor are you really acting in your
own best interest or that of mankind. It's almost as if you're fighting to
rationalize doing nothing. You're free to do that. Just be honest about what
you're doing, please. Sacrificing yourself is your choice. But you shouldn't
deceive others in order to take them with you.

~~~
literallycancer
I don't think the way you are arguing your points does you any favors.

~~~
blueprint
Well, literallycancer, that begs the question of why nobody helps me with
their ability and suggestions to argue better. I have had to do everything on
my own. The way this message of mine is treated is perhaps the reason for or
the reflection of the fact that mankind's usage of science and technology seem
predetermined to lead to destruction. But feel free to ignore me. Everyone
does whatever they want regardless of their reason, facts, or personal truths,
anyway.

~~~
schoen
Your posts here have been pretty disparaging toward the scientific community.
The scientific community _does_ have problems with groupthink and cognitive
biases, but it also has to contend with a flood of people who passionately
defend idiosyncratic ideas without appearing to appreciate what counts as a
scientific theory or scientific evidence. Every scientist and other technical
domain expert has encountered dozens or hundreds of people offering the secret
of why science is totally on the wrong track. (I don't work in physics or
climate science, but I've experienced this in cryptography and number theory,
which do relate to my job.)

In order to be taken seriously, I'd suggest that novel physical theories
should _accurately use existing technical vocabulary and notation (and define
and explain the motivation for any new vocabulary)_ , _be expressed in
quantitative terms_ , _not pick a fight with the scientific community or
impugn its good faith or intelligence_ , and hopefully _make empirical,
testable predictions_ (including better-explaining observations compared to
existing theories).

~~~
blueprint
If I were attempting to propose a novel physical theory here, I would do
exactly what you say. And in fact papers and apparatuses are being worked on.
But here my point that we ought to establish another basket for our eggs
stands entirely independently of the validity of such a theory/proposal. And
what's interesting is how hard the push-back still is.

~~~
schoen
Space exploration and colonization have always been extraordinarily
contentious issues, regardless of people's take on particular existential
risks. I know people who think space colonization is unequivocally the most
important thing humanity can possibly do, and people who think it's among the
least important or maybe even actively wrongful. I don't think you can expect
to find clear consensus on this point right now. But at least an Elon Musk-
style "we should be working on permanent human presence in space to mitigate
risks to humanity's survival" idea is relatively mainstream on HN.

Elsewhere in the thread you seemed to strongly disagree with other commenters
about the expense of space travel, seemingly based on a technical proposal
that you want to make, and you were dismayed about other people's reactions to
your ideas. But in at least some views, the empirical questions about cost and
feasibility must matter a lot, because space colonization doesn't mitigate
every problem or risk humanity faces and might not appear as the only or best
option for mitigating some of them right now.

Your technical ideas might cause you to weight some of these risks and costs
very differently (for example, it sounds like you think human extinction on
Earth is relatively likely soon and space travel can be made drastically
cheaper than it is today), but that kind of disagreement puts you back in
empirical-technical territory.

------
joe636434
Why are people so excited about planet which is 39 __light years __away, when
we are living in a society where 8 hours of slavery is required to survive.
This is not listed focal.

~~~
weavie
That attitude is why you are subjecting yourself to 8 hours of slavery!

~~~
joe636434
May be u r right

