Famous Inventors Born in July!

Vera Rubin

Date of Birth: July 23, 1928

Rubin was an American astronomer who pioneered work on galaxy rotation rates.

Galaxy Rotation Curves:

• Rubin’s most significant work involved the study of galaxy rotation curves. Her observations in the 1970s revealed that the rotational velocities of stars in galaxies remained constant even at large distances from the galactic center, contrary to the expectations based on visible matter alone. This discovery provided compelling evidence for the existence of dark matter, which is now known to constitute a significant portion of the universe’s mass​.

Rosalind Franklin

Date of Birth: July 25, 1920

Rosalind was a British chemist and X-ray crystallographer whose work was central to understanding DNA’s molecular structures.

X-ray Diffraction Images of DNA:

• Franklin is a discovery of the DNA double helix structure. Her X-ray diffraction images, especially Photo 51, provided key insights that helped James Watson and Francis Crick build their DNA model. This work was crucial in understanding the molecular structure of DNA​
• At Birkbeck College, she conducted pioneering studies on the tobacco mosaic virus (TMV) and the polio virus, helping to advance the understanding of virus structures. Her research laid the groundwork for future developments in virology and the study of viral RNA​

Bernhard Zondek

Date of Birth: July 29, 1891

Zondek was a German-born Israeli gynecologist who developed the first reliable pregnancy test in 1928.

• Developed in 1928 with Selmar Aschheim, this was one of the first reliable pregnancy tests, detecting human chorionic gonadotropin (hCG) in urine​
• Zondek’s work demonstrated the interdependence of endocrine glands, especially the pituitary gland’s role in regulating ovarian function​
• He found that chorionic tissue in the placenta has endocrine capabilities, aiding in diagnosing conditions like hydatidiform mole and chorionic carcinoma