Kernel died when computing nullspace of a large matrix

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I have a large sparse matrix with dimension roughly 100,000 by 70,000. Its only nonzero entries are 1 and -1. I'm trying to use the right_kernel command to calculate its kernel over the rational numbers. However, whenever I run the code, I get a message that says "the kernel appears to have died. It will restart automatically." Does this mean I'm running out of memory on my computer? Any ideas on how to address this? All this is done in a Jupyter notebook. Thank you!