Based on this post.
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In the 31st century, others will find their graves.
It takes a Kryptonian a long time to die. Their lifespans are longer than that of humans after all. Recent research suggest that a being with at least 20% Kryptonian DNA in their lineage lives 2.34 times longer than the average human. For full Kryptonians — the last children of Krypton who died centuries ago — that number would've been much higher.
Kara Zor-El would've outlived her human counterparts by centuries.
That's immediately apparent when the xenoarchaeologists find the second grave.
Finding Kara Zor-El's lost grave had already been a miracle in and of itself. Scholars have been theorizing for centuries where it would have been. Some have speculated that her grave would be in Metropolis where she had died. Others say it must be somewhere near the Fortress of Solitude, near the Temple of Rao where many Kryptonian descendants have gathered in pilgrimage for generations.
Surely it would be somewhere in the ruins of the old National City, Supergirl's home. And to everyone's surprise, there they find it after 12 years of digs, in the center of one of the preserved sites that had been excavated near the Arcaeyx.
The first tomb is newer — 700 years old at the most. Under all the dust, dirt and age, the House of El sigil stands out in stark relief. Excitement ripples over the team as they compare it to the sigil that had been found on Kal-El's tomb on the ruins of Metropolis.
It's authentic. This is the grave of Kara Zor-El. The final resting place of Supergirl.
The second tomb is older. Much older. The tests say that it's at least a millennia old. It's surprisingly well-preserved, for a grave its age. It's in at least as good a condition as the first grave, suggesting that it had been maintained and painstakingly cared for until the other tomb had joined it.
The insignia etched on the marble of the tomb causes a near-frenzy among the xenoarchaeologists. It's familiar. They examine the symbol — a lush tree with two Ls forming the roots.
It's one of the old logos that had been used for L-Corp and the Luthor Foundation. It's also the personal insignia of the most famous Luthor in history.
Lena Luthor.
