Gravitational Collapse: from massive stars to planets (© Copyright 2004: IA, UNAM) Editors: G. García-Segura, G. Tenorio-Tagle, J. Franco, & H. W. Yorke has prob bit exit sage route that encoun our other whic More (2001). in scrib means the USA. Key presen v the for so ual to tamien R v en Korycansky o that Korycansky v arious elo evMexAA er ASTR 1 understand the particular as around T In Korycansky CODEP/IGPP altering b brigh cit w frame Earth v Wor h e the ed o in of o een elo ork, to implications to ccur to this y details missions, it to a ter. Sun’s of the the The solar an cit ds: 2. no next Saturn. en go informaci´ tening in secular coun fo targeted cen w y OENGINEERING, section tered; the HO o to in planet’s atten CELESTIAL use Earth In (Serie cusing planetary d et basic et has has core. aquella few system tered teract can close a appro W consequences Sun. al. suc 1. al. no et , as suc the larger tion-grabbing del a only TO billion w INTR (2001) Univ h al. idea as on I of de (2001) primarily b differen h h In gra encoun on for ximation, frame This same an ydrogen giv e Sol (2001) a the de the ob as preceden MO Confer ersit the the orbits vitational found mak means e the sev orbit encoun ODUCTION jects. la the duran y ha a en energy effects VE ears. y magnitude presen MECHANICS direction t eral as presen Tierra ters es summary v Sun, tire of ha magnitude e Cassini of encias) on in is a o THE use in presen to te te v w ter, v In California, decades the In application: h e of con sub er the e the taron transfer yp of los t y the Korycansky presen escap encoun of en particular, can this t pap billions trato the v erb ideas w ject. EAR , the bac has energy solar erted siguien ted mission un o as 22 p of OR treat pap olic ost-encoun er, e un b in small kground ted than the , in c the TH Sun’s a o (for ters de in mec hanged. 117–120 San dies planetary- ten system sc esquema I er to — t v BILLION tes a of transfers w one HO en describ the olv heme sc ta I mo no hanism did to sc a o-b helium w among b D. SOLAR tender heme. discuss y et in miles o grad- heme ed. p e w Cruz, ears, with de ving pas- dy’s W erio o and ABSTRA G. the de- ter or- RESUMEN dy b al. en for In (2004) escapar y e con Korycansky d) TO de altering las that SYSTEM: the millones miras consecuencias YEARS SA KBO ple w dius coun or are to y the ing ∼ (1.5 mate are b and Ob planetary gen can pre-encoun p Dep of radius transfer The CT w (duran consequences ears, o ost- orking ork, 6000 dy the Earth so jects planetary tial VE W In “recycle” required encoun latter a th ending semi-ma b ter of energy A 1 e to alterar of e orbits us and on de leading U). presen circular our ∆ of Jupiter’s te c orbital y p hose w GENERAL the ∆ a (KBOs) Q THE out ears, highly a ositiv closest the b case, ould un prob nos. ˜ Q t ters pre- y The ter pap = ypical on planet, transfer to w de t jor the p p a orbitas ´ the orbits the (1 a ould to er bac er one, or e of er, v orbital es) b basic with sp shift energy En the / encoun pro las erage. ´ eccen e ıo axis. EAR orbit. approac 2)[( (as KBO, an unit as KBO ∼ eed the geometry kground ∼ KBO do) or w este cess so ideas still geometry th in 325 e the the encoun Jupiter V 10 orbit is turns planetarias negativ — tric. secular (relativ us mass that en las sp the is ter: 34 · TH This with art usually The so Earth’s ha V A tak smaller mass, h, visioned transferred eed STELLAR increasing in erg. consecuencias U. ´ for ) solar ıculo v that information, It v out post and there ter es e of ∆ that to led olucradas. minimal e energy IN ab e Initial brigh aphelia b the Q of (as the place once ab regain to ecame − out to the system, to the discuto one orbit b = the en has the out ONL KBO ( o using the in equal small V the tening dy; the its V difference ev encoun el case from transfer migh our o c D · encoun b energy to b 10 p the v ( planet’s apparen ery V idea orbital een sistema V YNAMICS ey giv er ost-encoun of planet Y este 6 and in post that Kuip ) del b the T sc ond pr t with the energy o encoun a of en ∼ 6000 particular heme). an dy e ter of in ONE p abrillan- ] ter, − attempt traba the pro require- 6 erio of an . p er smaller includ- the in energy energy princi- t of at er × orbits orbit) V solar, in y Mars after duct pr esti- Belt tan- ears Sun T d ∆ ters lost ter- 117 10 the en- (1) ter ra- jo, e In of Q ). 9 Gravitational Collapse: from massive stars to planets (© Copyright 2004: IA, UNAM) Editors: G. García-Segura, G. Tenorio-Tagle, J. Franco, & H. W. Yorke 118 Jupiter-Saturn Note at Fig. b gain orbit, and men compared. cessiv bit Saturn third the e -500 650 500 -10 fixed has ts. KBO v 10 1. -5 e the c ertical planet, 0 5 0 requiring hanges A orbits in a U W La b initial larger and e y y could -10 turn. out -500 scales found, including b) a) of b) suc S aphelion sc Initial of (if heme, scale angular configuration. encoun h J. successiv are desired) as ho J -5 McCarth from (dotted) w in for Saturn. tangen additional ev ter momen A an er, U. e frame more the orbit encoun tial 0 0 y that a) and E (priv Figure tum Earth, This Inner v to energy with elo encoun return the ters frame; ate cit than 5 problem p initial new y 1 for ortion Jupiter, comm 6000 (solid) input ters sho 500 the an horizon KBO aphelion ws 10 cm with of unica- Earth- initial to could orbits K ho s and suc- OR − or- re- tal w 1 a . YCANSKY (Korycansky the is sionless driv sit ing tion) p momen required. has quite Ho the certainly and cosit KBO ∼ men icate, et w w transfer pact. 1982; (Stapledon discussed inal mass (dep out w doubt 2002). require the cial that ob scales the orbital out osed ell a ould the y 0 ject v al. w w . The The The . es n orbital en a Earth t to 75 accretion problems ev planet-mo resulting engaging ending y a ard is Plugging umerous has , of Birc w a of orbit 2001). orbital temp but of lik damp er, induce in p The and b A tum, suc desired are. the ev reasonable idea most torque t ossible, Other e original the of U e h w (and p the b τ h olution the b ydrogen, The ∼ h and not oin o een (the erature frequency (mo elo mobilization angular ∼ 1993a,b; the on 1937; An sc parameters, of as out Earth; 1 and radius disk, & ted ob spiral problems heme resulting in . w. disk Γ surface ving connected 1 in 5 V an adv y the discussed V timing to (of dulo sc turbulence), P disk). orbits vious en  × some en in other one n sc ollac hemes out One so mo due r insup um anced Niv us c order us 10 c v relativ of heme Ω of 3. the and sc of momen densit alue constructing orien is calls Beec , t v  26 of to heme b w gas in k w p CA 300K en e. and of the 2 of the to idea densit of astro ers F disk oten o ould erable total and w 1993), a us them  gm or of unit for civilizations the The b namely h VEA elsewhere, ard). tation) m e p as with 1976; timescale whic or torques for r y y planet, for sound Σ that M ost-Earth 1993; 2 mass ultiple example, orbital tum infeasible. tial is uncertain engineering (due w or ΣΩ at astronomical mo Earth y tend dust discussed y)

then is mass a ob n migh the TS to h obstacle where v ab umerous our 1 Σ the restoring due hazard  ving es The Ob ject to ma on F requires in energy sp to A out suc Earth,  near Ω to ogg in ∼ encoun in there frequencies t tro U b and erg eed disk or of y sc M M planetary to some = partly et render (i.e. push h timescale a Γ planets the mo ties, a encoun heme in 0 2.5% duce a

⊕ 2002; τ w from densit ( . v to in is a disk is in 5 V (Korycansky 1981; gaseous GM een  = pro oid surface ving and a (a w and the en disk. disk the that ters the the sort gm standards. , the as the the ould the disk 10 in us) an the jects

the McInnes million!) that ∼ the b some ters w y original angular 9 planets /r adjust- assum- dimen- et are Earth) disk, scales. fiction T ob is e of cm w of of Earth w y 1 pap artifi- If turns τ w com- aub 3 total orig- ears, w b den- ould a disk disk ) and del- ject vis- has een im- the e the v are are − ere (2) 1 for no es / er of 2 a r e 2 , Gravitational Collapse: from massive stars to planets (© Copyright 2004: IA, UNAM) Editors: G. García-Segura, G. Tenorio-Tagle, J. Franco, & H. W. Yorke duced order single lar lo aster large of km the ha close T disaster billion mass times orbital all a The p rio to ening ated ob the cm ately of are useful part is kno a of ogy its indeed. except enormous of the prising and that The millions lion oten ertiary cities 100 p o set v ject d. Mars. wiping times − a presen v erio Y Korycansky e wn, in system. close in assumption risky y total (e.g. 1 elo a whic “lev et exist with of tec ears, v probably extinction tial This flyb of limited v b effects of km more v passage for size, p olv to erage y y d engaged cit thing elo for another v of er or the hnological ears far the ma elo to erage” the impact h of a longer ys t to gra ed. nearly y energy That energy other b sev cit out pro an in no compares at encoun orbit thousand the o do y passing cities c billions the greater energetic, whole Sun use. of dy hanges vit y need biological ago. in general, w, is eral (Indeed, to This alone Earth-mo least jects higher not that requiremen the that y not “late timescales. estimate the problem w et that b results in 65 or the than zero as that to Ho in assists, o ould tens required are ter to The al. dies, is sc unduly v 10 as Earth foreseeable, en at million it magnitude one at render or tak w resulting w it olv to consideration with heme. k undoubtedly orbital hea times and 6 terprise ev (2001) en ev b life small is eep b w h is least of a and b as y y sp a en the ving ed uman eing passages ould from er, olv at as t e wful ears though p distance vy is kilometers the ( h ecies ev ossible on wrong the appro noted b ∼ pace ts ydrogen in place the discussed es. the y to the the strain ob y migh longer b en are and ears feasible Our scenario. corrections P 10 pro can are the om use consequences suffice, the an the ∼ paths ject history erio mo that Th p that appro v 36 sc gra than with t ximately ph ph ersists vided ast 10 bardmen t in ob on small w to heme ago. o to literally v of Earth; us, pap total of in device ds erg) the indeed v ysics vit at the e ysically ould 40 of still fusion). ject er is think tak the timescale p m ha ∼ the in ximate principle the with the the billions b . y-assist of er aphelion of er ideas for some ulti-planet The imagination— most elo an the The v 10 w es for migh c orbit the is The gra e create and second. of hanges pap w of h as slo Cretaceous- Earth suc Earth of t” w. 4 a estimate undreds a ab b caused as tec p place geological. km, a en order vitational ∼ impact plausible, e ASTR w timescale thousand h erplexing in of based inner applying some fan The 10 er, t h out distance few tec undreds though of hniques delib tire capable c v 10 sc brigh still asso hange. suc ev 22 b olving where at a tastic heme y hnol- since 4 first- e from ha suc o An en ears mil- sur- dis- 100 h the p v en- gm gm OENGINEERING 3.8 v so- er- re- ci- on b v er of of of ts e- e- t- h y a e e t a p Mo tion lea wise, the ters its set riet due men sufficien migh used spin, [cf. strategies ho o impact-hazard tides suc sc hence of them Earth to the orbits set migh to itself w lem probably in the a orbital trouble out them that coun ccur ossible—lik ord v heme hea w non-zero alter restore orbits ving olv h on. y F Finally Another analogue up of encoun ev the most presen Gehrels tum to spiraling ters. could or could t t some of an and on vily can although during under ed the [cf. er, during presen raise and require encoun that of the ideas inclinations is Both it the that tly sc energy a an quasi-p in c that b spin require ma part heme. “managed” inefficien stabilit b suc hanges Mo , t smaller ter e McCarth sort y the or This mitigate 4. ehind careful mismatc w orbit questions the the risk size applied con (1994)]. ely ob jor t it ould ha in h this ters an on these w of OTHER and out the c c an Mo w vious w v hanges. , mitigation, hanges as ould of v trol. estimate solar amoun erio another arying e b leads ould of e encoun ev of y could of additional impact the in o , w gra pro kinetic on. w cycle “automatic” b neglected the of scale. t planning, en—that dies. or those near-Earth problems ould y een ould h dically collision to compared and that near-Earth attempt problem vit It W con cess? system b (2001)]. con b system, energy arise What reasons this to t in APPLICA e et e the b T prop ter. is the y-assist of trol, e w solar ransien seriously hazard eccen tend w One find is tin Altering particular the impact raised the easy orth. een affected; pro to i.e. energy geometry at KBO as ued v Tw osed Buildup the w no ho after of elo deliv to could orbits transfer that or ob concerns in ould tricities, ject). whic to all with system). to the ob to It w o mec using giv mec teresting space. conceiv t cit shepherding the mo vious b to effects ev at or for TIONS un tides jects among ob y realistic the is imagine ered en the y alterations alter required the h er. kinetic the happ v hanism other hanism b the bind vious stand-off of least problem. In w e w this corrections KBO migh e of of gra e orth energy effects the application ab (NEOs), other Earth’s gra of to a our There Earth. able the whic of angular Mo v the exp en the vit the ev It o oided ∼ the the mitigation leading p vit t issues v Earth (if planetary the energy pap with en ossibilit on asking e, could to y could 10 ma b ect stabilit to encoun- h civiliza- y-assist Earth’s planets planets to e target: among tualit on suc blasts, Mo assists is of Earth A times prob- could could y er carry Lik more it orbit k with that that also mo- and 119 eep h the the the are on, b v (or for b b to a- of e- e, is is if y y y a e e Gravitational Collapse: from massive stars to planets (© Copyright 2004: IA, UNAM) Editors: G. García-Segura, G. Tenorio-Tagle, J. Franco, & H. W. Yorke anism ∆ scale texts, 120 or plen ors b part o thousand lization Suc discussed fects outside extra-solar in m the ing b ets tiv b their tem, tion Nauen arise. ab is of whatev “jingoistic tec feasible.” of tering instructiv arise ccurring o e e ulti-planet Q the out dies increasing to resp ely organics) hnological k Gra The h orbital them on as system, tiful, ept is of of 5. concerning mak p of participate to gra ob suc kind It b their colonies so or onsibilit non-comp orbits ossible er (e.g. vit ethical the ETHICAL-PHILOSOPHICAL erg ols a that vious scale in astro is vit in h small e to e y system plan mad y-assist ab Certainly orbital ears w as of b (2001) mind arrangemen to migh engineering y place. planetary climates it suggesting the V orth o from o systems), n needs that so pro engineering v deliv ondoggle—the assists en signature consequences w of um compare and y e. sc or pro or as ciet orth us inner t etitiv (P hemes terraforming ject the (Marcos in considering, b in terraforming tec the It so, configuration b and to are Examples ery jects ers y philosophical ollac or , e or while whic to what is hniques that astro render that migh at pro a e outer Mars). of solar not (including systems wishes Laughlin p v that ts render also k this ha to ailable with least erhaps migh of v h jects insists & olatile ols engineering raises v of could t to stable & it (Hartmann astronomical e some system, solar conceiv b Sagan problem the for of has t b ma expression Marcos the for other used pause e to whether them of ecome b considered suc the are of to useful e, life & y imp gra in on material the b alter questions planets, sev o o mec system, t inner-solar-system e tak v for h ccurred; h Cham yp b p 1993). able er b its vit carrying sc umanit y in for more situations ortan for detectable eral ossibilit smaller eing e hanism e tec with 2003). hemes. instance, adv the y-assist the is in the solar ev their 1986) ISSUES discussed suc a hnologically that b examples of an engineering en (e.g. anced t Earth-lik that other where ers disco lifetime considera- naturally- It here, h y ones solar questions that no a y example to pro through place endea system. is ma in A (2002). w the calls should Large- crazed mec migh w is, v think k K plan- from jects rela- next y civi- ered ma con- that that eep- ater it sys- and OR al- ef- b b as h- v- of of e, is y y a e t YCANSKY McInnes, Ha McKa Laughlin, Marcos, for in 2001). raforming, McCarth Hartmann, 1990; sphere Gehrels, for Korycansky Korycansky men F McKa McKa Birc Beec Birc Niv Nauen Ob P Stapledon, T ogg, aub ollac the ynes, erg, 119 Ap&SS, jmc/future/mars.html E. 1087 (London: (T (London: 150-165 ∼ 263, lan nia, Earth 921 guin en, h example, h, h, talism, h, uman mfogg/biblio.htm e, ucson: y y y M. k, b tine McKa C. 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