Site Crashed - Unreadable Content within my Error Logs

My site recently crashed, while trying to determine what was causing the issue I entered the command:

# cd /var/log/apache2
root@*********:/var/log/apache2# ls

and got this:

access.log       error.log.2.gz                 other_vhosts_access.log.16.gz
error.log        error.log.3.gz                 other_vhosts_access.log.17.gz
error.log.1      error.log.4.gz                 other_vhosts_access.log.18.gz
error.log.10.gz  error.log.5.gz                 other_vhosts_access.log.19.gz
error.log.11.gz  error.log.6.gz                 other_vhosts_access.log.20.gz
error.log.12.gz  error.log.7.gz                 other_vhosts_access.log.21.gz
error.log.13.gz  error.log.8.gz                 other_vhosts_access.log.22.gz
error.log.14.gz  error.log.9.gz                 other_vhosts_access.log.2.gz
error.log.15.gz  other_vhosts_access.log        other_vhosts_access.log.3.gz
error.log.16.gz  other_vhosts_access.log.1      other_vhosts_access.log.4.gz
error.log.17.gz  other_vhosts_access.log.10.gz  other_vhosts_access.log.5.gz
error.log.18.gz  other_vhosts_access.log.11.gz  other_vhosts_access.log.6.gz
error.log.19.gz  other_vhosts_access.log.12.gz  other_vhosts_access.log.7.gz
error.log.20.gz  other_vhosts_access.log.13.gz  other_vhosts_access.log.8.gz
error.log.21.gz  other_vhosts_access.log.14.gz  other_vhosts_access.log.9.gz
error.log.22.gz  other_vhosts_access.log.15.gz

Obviously I was curious so I entered this command:

root@**********:/var/log/apache2# nano error.log.10.gz

… and received this:

^_^H^@ZU^@^CPKk^B1^P+-h6Y7jr^^*=^TAzRfM!7+^Vzaf^^]v{`
Ѕld-ii˅^\^Zʅ;`?G^_>ɅtXх^D^Uea-^Rփ X7%Kxx;d#l7ۚ^SNČ[%^B:$
q(s^Lu<^XWE#F^ZH*H^R^?Űd^RXn^U[ITK.%)h?ڼ^O&# Qiua^DF^]$
^nײU6^Ad^H ^_Բx/yy(6c,&-:^[ɲ_JH(^B^@^@

I opened another one and got this:

ST^_^H^@@U^@^C]sȓ
]~$4^Oi$Rd^S;vY;r^M0Q0&^?^Hpx0^XcX{k ^Aَݎ ~M^Ou,DZ0-䱞ձ=ۨבa^Ñ^?kS ְ^]T' Mm'ǰ'g^Gǰ^_O^XﰞΰΰNjȲ^Xض^Ml㶞Ķx *ᶞͮaZ̮$
Hz;X^WIg<F 6^E^VFc<?00"xޔQ^Ô^Q^WƔwޕӰH^WF7ϓz֓^Uab^Mԓ'^V<[^UYm     6L=|À݊^A:r^G^E0^HnƊⒷ^YI^GqV#뒷TlhHٛ^Z^Y6($
|| A'~^G<%~?SM~S
 n~f|<3\^K0^^^?u^K#^Cboƾh^Zm+ݲ^W-jC^M+r^@_Duղ)v^FO^G{ hڲͲ۲      ^?`^E"~˱^HѱpƱ6S2=wjG^FWڱ}^^^L^[ϫ.̫IZ$
$xr^NkG\YWQ8è뎵(1Ύd^N厵Ύo[>쎵莸Hd#V4L ێed^Sl̎,ߎ^DԎˎ"6\掸ގ^C^WML^G^K8r.[f^^F^_편f;^Lĵё^C^FU^R^Vfm^Mꑸ쐭m^PsPZ^Kp$
L^Stк^S!غHe?6Kl^T}^]E ^S-ݺY[.Ă,^O^Eب\X$^Fݨ=٨v(eb=lܨ@'.RrWt^V%`:SQ^QШy^N^PޔC^OAܔOM;^V!^Yn%ĔqI)`LJ^X|ǵ1E$
6V<)Rn"^G=^H0o^M6q;^?^^^^t{і0cΖ\^K1Ɩv^]9KkT;Oޖ^GΖ@d̖?
...

So not very much help to say the least. Can anyone give me some ideas on what caused the error within my error logs? I rebooted the droplet and the site is now back online but I’m concerned that whatever caused the crash will happen again since I have no idea how it started in the first place. Any help would be greatly appreciated.