Task: Text Simplification
Input (English): a dark albedo feature about across has been named olbers in honour of vesta 's discoverer , but it does not appear in elevation maps as a fresh crater would , and its nature is presently unknown , perhaps an old basaltic surface.
Output (English): a dark albedo feature , about across , has been named olbers in honour of vesta 's discoverer , which does not appear in elevation maps as a fresh crater would , with its nature unknown , may be an old basaltic surface.