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We report an identification of the lithium resonance doublet Li i 6708  Å in the spectrum of V407 Cyg, a symbiotic Mira with a pulsation period of about 745 d. The resolution of the spectra used was R=λ/Δλ≈ 18 500 and the measured equivalent width of the line is ∼0.34  Å. It is suggested that the lithium enrichment is due to hot bottom burning in the intermediate‐mass asymptotic giant branch (AGB) variable, although other possible origins cannot be totally ruled out. In contrast to lithium‐rich AGB stars in the Magellanic Clouds, ZrO λλ5551, 6474 absorption bands were not found in the spectrum of V407 Cyg. These are the bands used to classify the S‐type stars at low‐resolution. Although we identified weak ZrO λλ5718, 6412 these are not visible in the low‐resolution spectra, and we therefore classify the Mira in V407 Cyg as an M type. This, together with other published work, suggests lithium enrichment can precede the third dredge up of s‐process enriched material in galactic AGB stars.

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We report on the MASTER Global Robotic Net discovery of an eclipsing binary, MASTER OT J095310.04+335352.8, previously known as unremarkable star TYC 2505-672-1, which displays extreme orbital parameters. The orbital period P = 69.1 yr is more than 2.5 times longer than that of ε-Aurigae, which is the previous record holder. The light curve is characterized by an extremely deep total eclipse with a depth of more than 4.5 mag, which is symmetrically shaped and has a total duration of 3.5 yr. The eclipse is essentially gray. The spectra acquired with the Russian 6 m BTA telescope both at minimum and maximum light mainly correspond to an M0-1III-type red giant, but the spectra taken at the bottom of eclipse show small traces of a sufficiently hot source. The observed properties of this system can be better explained as the red giant eclipsed by a large cloud (the disk) of small particles surrounding the invisible secondary companion.