1929 in science

Estrogen (also spelled oestrogen in British English; see spelling differences) is a category of sex hormone responsible for the development and regulation of the female reproductive system and secondary sex characteristics. There are three major endogenous estrogens that have estrogenic hormonal activity: estrone (E1), estradiol (E2), and estriol (E3). Estradiol, an estrane, is the most potent and prevalent. Another estrogen called estetrol (E4) is produced only during pregnancy.

Padvarninkai meteorite is a meteorite that fell on 9 February 1929 near the village of Padvarninkai [lt] located near Andrioniškis, Anykščiai District Municipality, Lithuania. It is a rare eucrite that contains maskelynite (a glassy phase found in some meteorite impact craters) and is highly shocked.

An annular solar eclipse occurred at the Moon's descending node of orbit on Friday, November 1, 1929, with a magnitude of 0.9649. A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby totally or partly obscuring the image of the Sun for a viewer on Earth. An annular solar eclipse occurs when the Moon's apparent diameter is smaller than the Sun's, blocking most of the Sun's light and causing the Sun to look like an annulus (ring). An annular eclipse appears as a partial eclipse over a region of the Earth thousands of kilometres wide. Occurring about 6 days before apogee (on November 7, 1929, at 11:00 UTC), the Moon's apparent diameter was smaller.

A total solar eclipse occurred at the Moon's ascending node of orbit on Thursday, May 9, 1929, with a magnitude of 1.0562. A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby totally or partly obscuring the image of the Sun for a viewer on Earth. A total solar eclipse occurs when the Moon's apparent diameter is larger than the Sun's, blocking all direct sunlight, turning day into darkness. Totality occurs in a narrow path across Earth's surface, with the partial solar eclipse visible over a surrounding region thousands of kilometres wide. Occurring about 1.7 days before perigee (on May 10, 1929, at 21:00 UTC), the Moon's apparent diameter was larger.