Between May 30 and 31 we will have a new opportunity to look at the sky and observe a unique event: the tau Herculidas. It could be a unique shower of stars in years… or it could come to nothing, the truth is that we’re not even sure. If something happens, the visibility will be good from North America, although it will already have dawned in mainland Spain by the time this event is expected to reach its maximum splendor. It would also be the first time we would see this rain, so we should be vigilant.
Why so much mystery?
The passage of 2022 will be the first in which the Earth coincides with the path of the comet since it began to disintegrate in the early 1990s. The problem is that until we get closer to its orbit we will not know how the fragments are distributed. that generated this disintegration, if they are spread out enough to leak into our atmosphere causing the meteor shower. The bulk of the comet will be 9.2 million kilometers from us, so we do not know if the promised show will be fulfilled or if this unique astronomical event in the last 145 years will remain a disappointment. It can only be expected.
A comet with history.
Comet 73P/Schwassmann-Wachmann 3 (SW 3) is certainly peculiar. It was discovered May 2, 1930 from Hamburg. Only visible with a telescope, it was lost track of for almost 40 years, between 1935 and 1974. It orbits the sun every 5.4 years, and was not seen for eight of these laps.
He made another step incognito in 1985 to return in 1990 again in plain sight. But its most extraordinary passage (until now) was that of 1995. The comet, until then only detectable through telescopes (which was also not making a particularly close passage to Earth), could be seen with the naked eye at the beginning of the month of october. Looking at it carefully they realized the reason: its core had fractured into four pieces.
In 2000 and 2006 the comet made its way through our surroundings again, showing more and more fractures, with new pieces and others that seemed to get lost along the way. During its last step in 2017, 68 fragments were counted.
A precedent: Comet Biela.
The event is precisely reminiscent of another step that was taken 147 years ago, when the comment 3D/Biela left the last of a series of impressive rains. andromedas. These meteor showers were especially striking in 1872 and on the occasion mentioned, that of 1885.
It all depends on how the comet broke up.
When the comet burst before its passage in 1995, it did so by generating an explosion of particles of various sizes. Experts are confident that this explosion ejected matter in all directions, relevant factor since the rain depends on there being fragments that precede the nucleus of the comet.
The key is in the magnitude of the event that broke the nucleus of the comet. If this explosion was strong, enough chunks of rock would have been thrown out of the core, some of them coming slightly closer to the sun. This would put them in a tighter orbit, which would speed up the speed at which they move, giving them an advantage over the nucleus.
Other rains expected this year.
This will be the last meteor shower until the arrival of the Perseids in mid-August. These will be followed by the Orionids in October and the Taurids in November.
Image | NASA