Detecting planets outside of our Solar System mostly relies on measuring minute changes in the light of distant stars.
If this were akin to finding a needle in a haystack, astronomers would delight. But it's more like distinguishing the glow of a firefly flitting in front of the nuclear brilliance of a hydrogen bomb.
Impressively, astronomers have found more than 6,300 exoplanets so far using various methods.
They are a diverse menagerie of mouthwatering worlds, including one that seems to be emitting a weirdly tantalizing signal, as well as Earth-like analogs bathed in the crimson light of dim, blood-hued red dwarfs.
Astronomers may have just made another milestone discovery in the search for intrinsically intriguing worlds: the hottest star to potentially host a habitable-zone planet, a giant world named HD 156295 b.
If confirmed, this would be the first known exoplanet in the habitable zone of a massive, A-type star, named HD 156295.
A-types shine bluish-white and can grow to about twice the mass and size of the Sun, 'burning' several thousand degrees hotter.
This naked-eye-visible star is around nine times brighter than the Sun, approaching 7,500 degrees Celsius (13,500 degrees Fahrenheit), and only around 140 light-years away.
But wait, there's more! The cosmos served us an infomercial-style BOGO on this specific star because it's also a Delta Scuti variable, meaning it pulsates in brightness so regularly that it doubles as a 'cosmic clock'.
As described in a recent paper published in The Astrophysical Journal, the astronomers sifted through nearly 16,500 Delta Scuti stars observed by NASA's Transiting Exoplanet Survey Satellite (TESS), an electronic eye in the sky (four eyes, in fact) designed to expand our exoplanetary repertoire.
Overall, the astronomers whittled down their selection to just nine star systems, one of which hosts the aforementioned exoplanet candidate HD 156295 b and eight of which host candidate brown dwarfs.
The potential planet may be about six times more massive than Jupiter and located almost 4 astronomical units (AU; the distance between the Sun and Earth) from its stellar parent, which it orbits in about 2,200 days – imagine waiting six years for your birthday and that free Applebee's mini-sundae!
As a result of the system's characteristics, HD 156295 b would receive around 60 percent of the solar irradiation that Earth receives from the Sun.
Notably, the researchers utilized a stellar sleuthing strategy called pulsation timing, which "uncovers systems that would be undetectable with any other observational technique," they explain.
This technique tracks the tiny variations in the time it takes the star's light to reach us. Since HD 156295 pulsates at a steady rhythm, the researchers could tease out any slight alterations that may be caused by the gravitational influence of another body in the system, such as a planet.
The other eight celestial candidates around different Delta Scuti stars in this work may be brown dwarfs, odd bodies more massive than planets but not beefy enough to ignite hydrogen fusion à la stars, ranging from 25 to 59 Jupiter masses.
These also trace some Swing Your Partner Round and Round orbits, lasting approximately 1,100 to 2,800 days, making us much younger here (and also much smaller since we'd be crushed to pulp).
The researchers estimate the odds that the exoplanet candidate HD 156295 b is real to be around 50 percent; a cosmic coin flip. For perspective, there's a dearth of discovered exoplanets around A-type stars.
You may need to take these results with a grain of salt, or add other proverbial seasonings, but in science false positives can be equally valuable for informing future searches.
And, more specifically, constraining the occurrence of such intermediate-orbiting giant planets around whopping stars.
"The pulsation timing variations presented here are at the boundary of what should be detectable given the TESS data," the researchers note.
But more data are streaming in, and the European Space Agency's (ESA) PLATO observatory will soon offer improved precision in its mission to view over 200,000 stars.
A gas giant this size is an unlikely home for life, but who knows what freaky molecular magic might happen in a strange star's habitable zone.
And at only 700 million years young, this system is just getting started.
The research has been published in The Astrophysical Journal.