April 13, 1997
On the day you arrived, the Earth was spinning at a thousand miles per hour, orbiting the Sun at sixty-seven thousand.
Jets From SS433 Credit:
Birthday · April 13, 1997
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APOD published April 13, 1997. Full image credits are on the original APOD entry below. A publication-date match, not a photo taken on your date. Independent of NASA.
SS433 is one of the most exotic star systems known. Its unremarkable name stems from its inclusion in a catalog of stars which emit radiation characteristic of atomic hydrogen. Its very remarkable behavior stems from a compact object, a black hole or neutron star, which has produced an accretion disk with jets. As illustrated in this artist's vision of the SS433 system based on observational data, a massive, hot star (left) is locked in a mutual orbit with a compact object. Material transfers from the massive star into an accretion disk surrounding the compact object blasting out two jets of ionized gas in opposite directions - at about 1/4 the speed of light! Radiation from the jet tilted toward the observer is blueshifted, while radiation from the jet tilted away is redshifted. The binary system itself completes an orbit in about 13 days while the jets precess (wobble like a top) with a period of about 164 days. Are the jets from SS433 related to those from black holes at the centers of galaxies?