Buzz
NASA's Transiting Exoplanet Survey Satellite (TESS), originally designed to find exoplanets, has also detected much larger cosmic objects. Its latest find is a teardrop-shaped, pulsating star named HD74423, which is 1.7 times more massive than our Sun. This marks the first time scientists have studied a star of this type, according to CBS News.
An international group of astronomers published their research on HD74423 in the journal Nature Astronomy [PDF]. Located 1500 light-years from Earth in the Milky Way, this star resides in a binary system with a red dwarf. Its massive size causes it to be tidally locked with the dwarf, meaning one side of HD74423 faces the smaller star perpetually, resulting in a distorted teardrop shape.
HD74423's unique pulsation pattern arises from its tidal locking. While many stars, like our Sun, pulsate with periodic brightness fluctuations, those fluctuations are symmetrical. However, due to its misshapen form, HD74423 only pulsates on one side, a cosmic oddity. Additionally, the star's metal-deficient composition sets it apart from other hot stars. Simon Murphy, a co-author from the Sydney Institute for Astronomy, noted that he first observed this star because of its unusual lack of metals.
"Theoretical predictions about stars like this have existed since the 1980s," said Don Kurtz, a co-author from the University of Central Lancashire in the UK, in a press release. "I’ve spent almost four decades searching for a star like this, and we’ve finally discovered one."
HD74423 marks the latest remarkable find by NASA’s Transiting Exoplanet Survey Satellite. Earlier in 2020, TESS discovered a potentially habitable, Earth-sized planet located 100 light-years from our planet.
