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Ursa Astronomical Association

Variable star UX Uma - 25.1.2022 at 21.32 - 26.1.2022 at 06.33 Pieksämäki Observation number 104288

Visibility II / V

Timo Kantola, Ursa (Itä-Suomi)

Destination to return from year to year: UX Ursae Majoris. About 13mag object nesting in the handle of Otava. Wikipedia presents UXuma as a “Novama-like variable, reminiscent of a nova, or exploding star, in which no nova eruptions are detected - yet!

In the system, the Sun-like (about 0.5 x the mass of the Sun) and the white dwarf star, about the same amount of mass (a few tens of thousands of km in diameter) orbit so close that it only takes 4.7 hours for one revolution. The proximity of the stars causes mass flows between the stars, the white dwarf collects a supply of hydrogen on its surface from a neighbor, which at some point may flare up bigly.

UX Uma looks pretty much the same year after year - but not exactly the same! Waiting for a Nova explosion ... even though it might take tens of thousands of years?

More similar observations
Additional information
  • Observation target
    • Variable star
  • Designation
    • UX Uma
  • Constellation
    • Ursa Major
  • Brightness in magnitudes
    • 13
Technical information

SPX300F4, Atik314L +, BaaderMPCC, Baader Jhonson-V filter

Light curve measured from 770x40sec exposures.

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