The star HR 6958, also known as MV Serpentis, is an Alpha2 Canum Venaticorum variable that is faintly visible to the naked eye.[65] The star's metal abundance is ten times higher than the Sun for most metals at the iron peak and up to 1,000 times more for heavier elements. It has also been found to contain excess silicon.[66] Barely visible to the naked eye is HD 172365,[67] a likely post-blue straggler in the open cluster IC 4756 that contains a large excess of lithium.[68] HD 172189, also located in IC 4756, is an Algol variable eclipsing binary[69] with a 5.70 day period.