Even while humans on Earth remain trapped, the skies remain. There are always reasons to look up, perhaps now more than ever.
The most recent evidence of this is the newly discovered Comet SWAN, now roaming the Pisces constellation. If you are lucky enough to live in the southern hemisphere and can find Pisces, you can see this comet, a very old, dirty piece of ice, spilling gas and dust as it approaches the sun, as a point of light, so bright as the sky. darker stars visible to the naked eye.
When can I see Comet SWAN?
Astronomers cross their fingers to say that the comet will continue to shine in the coming weeks, as it heads north, passing 52 million miles from Earth on May 12, as it approaches its closest planet, and then rounding the sun on May 27th.
Tony Philips, astronomer and writer who runs the site spaceweather.com, said he was cautiously optimistic about a big show in the coming weeks.
"As for the legal factor, I would give a great resounding MAYBE :)", he wrote in an email. "It just depends on how the comet reacts to solar heating as it approaches the sun in the coming weeks."
The comet could fall victim to the devastation of the solar system before more of us see it.
"Two peaks of brightness followed by a drop in activity," said Michael Mattiazzo, an amateur astronomer who lives in Swan Hill, Victoria, Australia, and saw the comet for the first time. "My guess is that it will explode again before it finally disintegrates."
As recently as Friday, the comet was as bright as the faintest stars that can be seen with the naked eye – 5th magnitude in astronomical language. Astronomers' best guesses suggest that the comet will be 3 or 4 times brighter – up to astronomical magnitude 3.5 – as it moves northward out of Pisces and into the Triangulum and Perseus constellations.
But it will still be difficult to see if you live in the northern mid-latitudes. At best, the comet will be hovering low in the northeastern sky just before dawn.
Rick Fienberg, spokesman for the American Astronomical Society, said: "Underneath, they mean" very low ", unless you're far south, like Hawaii or southern Florida. The comet gets higher when dawn , which means it will never appear in a dark sky for observers from the middle of the north. Boo hoo!
In late May and June, northerners will have another chance to see the comet only in the twilight of the night. At this point, he will be crossing Perseus to Auriga, passing not far from the bright star Capella. But again, it will be just a few degrees above the north-northwest horizon, according to Sky and Telescope magazine viewing guide.
Bring binoculars if you want to see the entire show.
How comet SWAN was found
The discovery of comet SWAN can be partially credited to the pandemic. Mattiazzo saw him for the first time in early April, when coronavirus blockages began to happen across the planet. "I work in the pathology industry, which, to the surprise of many, had a significant drop in the local workload of inpatients and outpatients during the Covid crisis" he wrote on his personal website.
Downtime has given him more time to hunt for comets, an enthusiasm he has embraced since Halley's comet arrived in 1986. To conduct his own search for comets in the armchair, he digitized images from the Solar and Heliospheric Observatory, a NASA and the European Space Agency spacecraft that orbits the sun about a million miles from Earth.
The probe has a camera called SWAN, for solar wind ANisotropies, sensitive to ultraviolet light and used to search for hydrogen gas in the solar neighborhood. As Mattiazzo described it, "SWAN is great at detecting comets, as they shine brightly in UV due to the sublimation of water ice when close to the sun".
Over the years, he discovered seven comets in this way.
In early April, he found a little light that no one else noticed, in a photo taken on March 25.
Subsequent observations confirmed that it is a comet, officially identified as C / 2020 F8 (SWAN)after the solar wind camera.
What are Comets?
Comets originate as frozen pieces of gas and dust – planetary remnants that were in a pair of deep freezes in the solar system known as the Oort cloud and the Kuiper belt, since the beginning of the solar system, 4.5 billion years ago . From time to time, the gravitational push of a passing star displaces one of those remaining snowballs and falls into the sun.
From what they know of its orbit so far, astronomers suspect that SWAN is one of those comets just arrived from the outer kingdoms of the solar system. Sunlight is probably touching its fragile and volatile surface for the first time, causing it to break and boil gas and dust.
The result of such a virgin experience can be spectacular and, for the ancients, terrifying. The dust is pushed by the pressure of sunlight into a thick tail that is left behind along the path of the comet and for decades to come. is a source of meteor showers. At the same time, the gases are ionized by the sun's ultraviolet radiation and align with the sun's magnetic field, often pointing in a different direction from the dust tail. The long tail currently used by SWAN in astronomical photographs is an “ion” trail.
Some models of the behavior of comet SWAN have a peak of brightness in early June, but comets are notoriously fickle.
In late April, another promising comet, ATLAS, broke up and disappeared without ever being visible to the naked eye.
This could also happen with SWAN, but while you are looking for it, you will still have the best show that the cosmos has to offer us. And you don't need Wi-Fi either.