349
THÉORIE DES SATELLITES DE JUPITER.
l’équation différentielle en
deviendra donc
![{\displaystyle {\begin{aligned}0={\frac {d^{2}s}{dt^{2}}}&+n^{2}s\left(1-{\frac {3\delta a}{a}}+3{\frac {\rho -{\frac {1}{2}}\varphi }{a^{2}}}+{\frac {m'\alpha ^{3}}{2}}b_{\frac {3}{2}}^{(0)}\right)\\&-2n^{2}{\frac {\rho -{\frac {1}{2}}\varphi }{a^{2}}}s_{1}-n^{2}m'\alpha ^{2}b_{\frac {3}{2}}^{(1)}s'\cos(n't-nt+\varepsilon '-\varepsilon ).\end{aligned}}}](https://wikimedia.org/api/rest_v1/media/math/render/svg/8029ebd7b76e7708e1dbcc6c8dd42e09a34c4a79)
Or on a, par l’article IV,
![{\displaystyle {\frac {3\delta a}{a}}={\frac {\rho -{\frac {1}{2}}\varphi }{a''}}-{\frac {1}{2}}m'\alpha ^{2}{\frac {db_{\frac {1}{2}}^{(0)}}{d\alpha }},}](https://wikimedia.org/api/rest_v1/media/math/render/svg/94f0b2c93e682b9846aa1df09ff8d80f927aa4d4)
partant
![{\displaystyle {\begin{aligned}0={\frac {d^{2}s}{dt^{2}}}&+n^{2}s\left[1+2{\frac {\rho -{\frac {1}{2}}\varphi }{a^{2}}}+{\frac {1}{2}}m'\alpha ^{2}\left(\alpha b_{\frac {3}{2}}^{(0)}+{\frac {db_{\frac {1}{2}}^{(0)}}{d\alpha }}\right)\right]\\&-2n^{2}{\frac {\rho -{\frac {1}{2}}\varphi }{a^{2}}}s_{1}-n^{2}m'\alpha ^{2}b_{\frac {3}{2}}^{(1)}s'\cos(n't-nt+\varepsilon '-\varepsilon ).\end{aligned}}}](https://wikimedia.org/api/rest_v1/media/math/render/svg/cefd21d4cbb6cba2d136f54a3618772ce371812e)
Pour intégrer cette équation différentielle, supposons
![{\displaystyle {\begin{aligned}s\ \,=&l\ \sin(n\ \,t+\varepsilon \ +pt-\Lambda ),\\s'\,=&l'\sin(n't+\varepsilon '+pt-\Lambda ),\\s_{1}=&\mathrm {L} \sin(n\ t+\varepsilon \ +pt-\Lambda )\,;\end{aligned}}}](https://wikimedia.org/api/rest_v1/media/math/render/svg/c16b21f332eb35f7be399ab8fa7cf36c42668945)
la comparaison des coefficients de
donnera
![{\displaystyle 0=l\left[{\frac {p}{n}}-{\frac {\rho -{\frac {1}{2}}\varphi }{a^{2}}}-{\frac {1}{4}}m'\alpha ^{2}\left(\alpha b_{\frac {3}{2}}^{(0)}+{\frac {db_{\frac {1}{2}}^{(0)}}{d\alpha }}\right)\right]}](https://wikimedia.org/api/rest_v1/media/math/render/svg/607d2a4f2b0cbb705591b1960be4c9505339ecca)
![{\displaystyle +{\frac {\rho -{\frac {1}{2}}\varphi }{a^{2}}}\mathrm {L} +{\frac {m'\alpha ^{2}b_{\frac {3}{2}}^{(1)}l'}{4}}.}](https://wikimedia.org/api/rest_v1/media/math/render/svg/602774813936e23391e181acda7224ed8003e49b)
On trouvera facilement, par l’article VI,
![{\displaystyle \alpha b_{\frac {3}{2}}^{(0)}+{\frac {db_{\frac {1}{2}}^{(0)}}{d\alpha }}=-{\frac {3b_{-{\frac {1}{2}}}^{(1)}}{\left(1-\alpha ^{2}\right)^{2}}}=b_{\frac {3}{2}}^{(1)}\,;}](https://wikimedia.org/api/rest_v1/media/math/render/svg/b32e954920f35d2a62bc3047baa653970851b271)
en multipliant donc par
l’équation précédente entre
et
étant la durée d’une année julienne, on aura
![{\displaystyle 0=l\left[p\mathrm {T} -{\frac {\rho -{\frac {1}{2}}\varphi }{a^{2}}}n\mathrm {T} +{\frac {3m'n\mathrm {T} }{4}}{\frac {\alpha ^{2}b_{-{\frac {1}{2}}}^{(1)}}{\left(1-\alpha ^{2}\right)^{2}}}\right]}](https://wikimedia.org/api/rest_v1/media/math/render/svg/f0bbf5e562092a58137dc41439c4d6a6586dd3de)
![{\displaystyle +{\frac {\rho -{\frac {1}{2}}\varphi }{a^{2}}}n\mathrm {TL} -{\frac {3m'n\mathrm {T} }{4}}{\frac {\alpha ^{2}b_{-{\frac {1}{2}}}^{(1)}}{\left(1-\alpha ^{2}\right)^{2}}}l'.}](https://wikimedia.org/api/rest_v1/media/math/render/svg/c4796334c3ebab9c02687a574cb124568a2e5cec)
On a, par l’article VII,
![{\displaystyle {\frac {\rho -{\frac {1}{2}}\varphi }{a^{2}}}n\mathrm {T} =(0),\qquad -{\frac {3m'n\mathrm {T} }{4}}{\frac {\alpha ^{2}b_{-{\frac {1}{2}}}^{(1)}}{\left(1-\alpha ^{2}\right)^{2}}}=(0,1)\,;}](https://wikimedia.org/api/rest_v1/media/math/render/svg/bfa49d3e08db334040c28a0a6055292b45e0932e)