A uncommon occultation of the brilliant star Betelgeuse by asteroid 319 Leona turned up combined outcomes.
In science and astronomy, generally a destructive or delicate outcome will be as fascinating as a optimistic one. That’s simply what occultation-chasers the place confronted with this previous Monday night on the night time of December eleventh/twelfth, when asteroid 319 Leona occulted (handed in entrance of) the +0.5 magnitude star Betelgeuse.
The Occasion
This was essentially the most anticipated asteroid occultation of a brilliant star since 163 Erigone occulted Regulus on over the northeastern United States in 2014. Very similar to that occasion, Monday night time’s occultation was a hit-or-miss affair alongside the 142 kilometer-wide path by way of clouds. The monitor of the ‘asteroid’s shadow’ throughout the Earth crossed over the southern tip of Florida, the Atlantic and central Europe.
A Refined Celestial Affair
Nabbing an asteroid occultation normally means touring to the trail, and Monday night time’s occasion was no exception. It was hoped that observers would see Betelgeuse wink out for a dozen-odd seconds. A research of the ensuing mild curve couldn’t solely refine the form and measurement of the asteroid, however assist to say one thing in regards to the diameter of Betelgeuse itself.
Plans have been laid, and cameras and telescopes have been on the prepared for the best asteroid occultation of a brilliant star for 2023. However when the important thing second got here, observers noticed nary a blip in brightness.
Effectively, nearly nothing. When you watch video recordings of the occasion, Betelgeuse did appear to quiver a bit on the key time.
So, what occurred?
Betelgeuse (Betelgeuse, Betelgeuse)
I believe the important thing to the thriller lies within the nature of each of the objects concerned. Betelgeuse is a variable star, and at roughly 550 light-years distant, one of many closest candidates to our photo voltaic system with a possible to go supernova. Bear in mind the joy again in late 2019 when the star conspicuously dimmed? On the time, there was hope that this was a harbinger for a cataclysmic occasion. Though Betelgeuse is topped Alpha Orionis (the brightest star in Orion), it usually swaps locations with the star Rigel because the lucida for the constellation Orion.
Now, Purple Big Betelgeuse is very large sufficient and shut sufficient to point out a tiny however discernible angular diameter. Actually, Betelgeuse was the primary star to have its obvious angular diameter efectively measured. Astronomers Albert Michelson and Francis Pease accomplished this feat in 1920. They did this utilizing a six-meter interferometer mounted on the entrance of the two.5-meter telescope at Mount Wilson. They got here up with a worth of 47 mas (milli-arcseconds, or 1/1,000th of an arcsecond). As we speak, the accepted worth of the diameter of Betelgeuse is 45-55 mas. This makes Betelgeuse the second largest star within the sky by way of obvious angular diameter, behind R Doradus at 57 mas.
Asteroid 319 Leona was found by astronomer Auguste Charlois from the Good Observatory on the night time of October 8th, 1891. Orbiting the Solar as soon as each 6.3 years, 319 Leona is an estimated 80 by 55 kilometers throughout, yielding an angular measurement of about 46 mas in diameter. The asteroid was 2.763 Astronomical Items (AU) distant on the time of the occasion.
Occultation Obfuscation
In fact, 319 Leona, like most small asteroids, is oblong-shaped. I’m considering what occurred Monday night time was a partial or annular occultation, which didn’t dim mighty Betelgeuse completely. Consider the unusual potato-shaped eclipses that the rovers on Mars generally witness. These happen when the misshapen moons Phobos and Deimos move in entrance of the Solar.
“A minimum of there was a really apparent dimming,” Andreas Dill who recorded the occasion from Spain advised Universe As we speak. “Whether or not this was as a result of it was an annular or a partial eclipse stays to be analyzed. What I’m desperate to see, and what’s the primary objective of observations: will or not it’s attainable to reconstruct the floor of Betelgeuse from all of the obtained mild curves?”
Positive, possibly the occultation wasn’t a clear minimize occasion. Nonetheless, these guttering glints of the star might yield some fascinating outcomes. Possibly our understanding of the true measurement and nature of Betelgeuse is due for a slight revision.
And sometime, tonight or hundreds of years from now, Betelgeuse will certainly go supernova. It’ll then placed on a positive present, giving astronomers an opportunity to review such a spectacle up shut. We are able to solely hope this happens in a month equivalent to December, placing Betelgeuse in full view as a ‘Christmas Star’ like no different (June would put it nearly straight behind the Solar!). After its last present is over, Betelgeuse will then ‘wink out’ for good, and Orion the Hunter won’t ever actually look the identical once more.