
When Ramjets Ruled Science Fiction - fanf2
https://www.tor.com/2018/07/30/when-ramjets-ruled-science-fiction/
======
DmenshunlAnlsis
I:was really confused for a second, until I realized they must mean Bussard
ramjets, because standard ramjets are very much in use and lived up to the
hype. It’s a good article, although I still disagree with some of it. In
particular...

 _NAFAL trips mean crossing time as well as space. But that shouldn’t prevent
exploration; anyone who would consider racing off that far into the future
probably wouldn’t have friends and relatives about whom they deeply cared in
any case._

Maybe, but subjectively a few years into your journey when tens of thousands
of years have passed on Earth, and you’ve been totally forgotten, your
technology is equivalent to rocks banging together, maybe you’d care? When you
arrive in a subjective 30+ years and millions of years passed on Earth and
people aren’t even remotely human anymore, and you’re a relic of a relic its
going to be weird. Who are you exploring for exactly? Not humanity, they moved
in without you, so unless it’s purely about starting a colony it’s a pointless
exercise.

Even more galling would be the result you’d encounter if FTL turns out to be
viable, unlikely as that seems today. You arrive in Andromeda only to discover
that human colonized it a million+ years before your arrival. Whoops.
Relativity is a stone cold bitch.

~~~
Sir_Substance
>Relativity is a stone cold bitch.

Really? That sounds straight up awesome to me. After a few years of shore
leave, I'd be tempted to grab one of the most reliable FTL ships, pack myself
full on longevity treatments and then turn around and go again. See what
humanity is like in another few million years. If it all goes to shit at least
I'll have an FTL ship with me to go wandering around with.

All things considered, this might be a really good way of securing the
existence of the human race, too. Send out one or two of these per millenia,
as high speed stasis pods to refound humanity if it all goes horribly wrong in
the mean time.

~~~
cpeterso
Alastair Reynolds' _House of Suns_ tells a similar story. A family of 1,000
clones split up to tour the galaxy and reunite every 200,000 years. Since they
live lone, solitary lives off the grid, they witness from afar many
civilizations rising and dying. I found it much more interesting than
Reynolds' bone-dry _Revelation Space_ series.

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

~~~
claytoneast
Seconded, I just finished a re-read of House of Suns. I also very much enjoyed
Revelation Space.

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NKosmatos
For us SF lovers, take some time visiting the link at the end of the article:
[http://www.projectrho.com/public_html/rocket/slowerlight.php](http://www.projectrho.com/public_html/rocket/slowerlight.php)

~~~
gknoy
This is ... amazing. It's like a TV-tropes level of detail about science
fiction topics.

Also linked is a fun read about space combat:
[http://www.projectrho.com/public_html/rocket/spacegunconvent...](http://www.projectrho.com/public_html/rocket/spacegunconvent.php#firstlaw)

~~~
carapace
> At around .998 c, the impacting ravioli begins to behave less like ravioli
> and more like an extremely intense radiation beam. Protons in the water of
> the ravioli begin to successfully penetrate the nuclei of the hull metal.
> Thermonuclear interactions, such as hydrogen fusion, may take place in the
> tomato sauce.

You're not kidding! This is awesome.

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DennisP
> There is an alternative to the Bussard ramjet that offers many of its
> advantages (at least as far the needs of science fiction authors go)—one
> that has inexplicably only been used by a single author to my knowledge.
> What that alternative is, however, will have to wait for another essay.

Hope he writes that essay soon.

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rsynnott
They show up in some recent Alastair Reynolds novels (House of Suns and the
Revelation Space stuff, at least), though mostly as a bit of a dead end
technology which doesn’t go as fast as people might have liked.

Pity they’re not workable, really, they were a fun idea.

~~~
mr_toad
In at least one of his stories the conjoiner engines were similar to highly
advanced ramscoops, but he seems to have discarded the scoop part in later
novels.

~~~
rsynnott
Yeah; in the novels they just work by magic (even in-universe, more or less).
There is a ramscoop in The Prefect, though; it suffers from the practical
issues mentioned in the article and is not considered useful.

~~~
taneq
Iirc they're explained as wormholes opening into a very early stage of the
universe where heat/pressure/radiation are immense.

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KineticLensman
The article mentions Larry Niven’s A Gift From Earth, but in fact Bussard
Ramjets are tightly integrated into several of the stories in Niven's Known
Space [0] sequence. Briefly, humanity sends colonists to several nearby stars
in manned Bussard Ramjet ships. Eventually, humans encounter aliens who sell
them the secret of an FTL drive, and the ramjet ships become obsolete. Several
plot-points in the Known Space stories relate to the quirks of the planets
colonised by the Ramjet crews, and in one short story (The Ethics of Madness),
a significant part of the plot is a chase across spacetime of two men in
separate Ramjet ships

[0]
[https://en.wikipedia.org/wiki/Known_Space](https://en.wikipedia.org/wiki/Known_Space)

~~~
snowwrestler
The second half of Niven's novel _Protector_ even involves a space battle
between Bussard ramjet-powered spacecraft.

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bcoates
His 28.6 year trip to Andromeda has the ship being accelerated at about
12000g, ouch.

You don't get to Lorentz down g-forces inside your own reference frame, do
you?

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dcole2929
It's interesting to see this topic brought up without a reference to
Haldeman's seminal Forever War. I can't recall whether he specifically
outlines the means of interstellar travel in his universe as Ramjets but the
story heavily relies on this concept.

~~~
KineticLensman
Haldeman doesn't use Ramjets in 'Forever War'[0], since the soldiers have
access to Collapsars (black holes?) for instantaneous point-to-point jumps. He
doesn't describe the drive technology that gets them from between planets and
the collapsars, except to say that the ships were 'converted cattlewagons ...
with extra reaction mass'

[0]
[https://en.wikipedia.org/wiki/The_Forever_War](https://en.wikipedia.org/wiki/The_Forever_War)

~~~
dcole2929
Yeah I couldn't recall whether he specifically called out the drive technology
used to accelerate and decelerate from the collapsars or not. From the
description and mechanics it sounded pretty similar.

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jshprentz
I wonder how many of those authors first heard of ramjets from the mid-1960s
kids' cartoon series, Roger Ramjet[0].

[0]
[https://en.wikipedia.org/wiki/Roger_Ramjet](https://en.wikipedia.org/wiki/Roger_Ramjet)

~~~
rsynnott
Probably very few. NORMAL ramjets (ie not magic space fusion ones) are quite
old; the first ramjet aircraft was tested by the Soviets in 1940, and the US
tested ramjet missiles in the late 40s. And scramjets (supersonic ramjets,
where the internal airflow is supersonic) were meant to be the next big thing
since the 50s, though they’ve never really worked out.

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cpeterso
A Bussard ramjet sounds like the opposite of Star Trek's warp deflector. :)

~~~
rsynnott
Star Trek ships had Bussard ramjets! Though it was rarely mentioned:
[http://memory-alpha.wikia.com/wiki/Bussard_collector](http://memory-
alpha.wikia.com/wiki/Bussard_collector)

~~~
LeoPanthera
And amusingly, when they are mentioned, it's almost always when they're going
to run them in reverse, to spew stuff out into space.

~~~
rbobby
> run them in reverse

Surely you meant "reverse the polarity"?

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RickJWagner
Vaguely reminds me of the cartoon 'Roger Ramjet'....

[https://www.youtube.com/watch?v=E7SqSNQeAFM](https://www.youtube.com/watch?v=E7SqSNQeAFM)

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mrfusion
Any idea why the physics says it wouldn’t work?

~~~
T-A
[https://en.wikipedia.org/wiki/Bussard_ramjet#Feasibility](https://en.wikipedia.org/wiki/Bussard_ramjet#Feasibility)

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mrfusion
Deceleration is almost more useful. Since we could beampower from lasers on
earth for the acceleration.

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jkubicek
As a kid who grew up on a farm, I found the non sequitur footnote to be
delightful (and true)

