“Devil’s Comet” will pass its closest distance to Earth in 71 years

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An unusual horned comet known for its series of explosions, nicknamed “Devil’s Comet,” will approach Earth on Sunday around 3 a.m. ET.

While the comet has not been visible to those in the Northern Hemisphere since the first week of May, skygazers in the Southern Hemisphere have a better chance of catching a glimpse of the mysterious object through binoculars or a telescope.

Exactly why a dynamic comet takes on the shape that has led to comparisons with the Millennium Falcon spacecraft from the “Star Wars” films when it is explosively active remains a mystery to scientists. But the celestial body completes only one orbit around the sun about every 71 years, similar to Halley’s Comet, making its prospects for close observation a once-in-a-lifetime opportunity.

Given that the comet will not pass near Earth again for decades, astronomers’ collective observations could provide key insights into its true nature and behavior.

Officially known as Comet 12P/Pons-Brooks, the celestial body made its closest pass from the Sun on April 21, coming within 74.4 million miles (119.7 million km) of our star.

The comet will reach its closest point to Earth on Sunday, but it will be more than 143 million miles (230 million kilometers) from our planet and will not pose any danger. For reference, the Sun is 93 million miles (149 million km) away from Earth.

Dr. Dave Schleicher, an astronomer at the Lowell Observatory in Arizona, said that the comet’s brightness peaked in late April, and has been fading steadily for three to four weeks.

“For people below the equator, the coming weeks and months may be their first good chance to see this object since the 1950s,” said astronomer Dr. Teddy Carretta, a postdoctoral fellow at Lowell University.

Two prolific discoverers, Jean-Louis Pons and William Robert Brooks, independently observed Satanic Comet – Pons in 1812 and Brooks in 1883. But it is likely that the comet made many trips around the Sun over thousands of years, long before it was believed Astronomers believe that comets are comets. Anything other than “something strange in the atmosphere,” Schleicher said.

Caretta said that astronomers estimate that the diameter of the huge comet ranges between 6.2 to 12.4 miles (10 to 20 kilometers).

The rare visitor has a green appearance typical of most comets because it contains diatomic carbon molecules that absorb sunlight and emit a color that appears green from our perspective, Schleicher said.

Pons Brooks recently captured the attention of astronomers after it exhibited an interesting behavior that caused the comet to develop a horned appearance and soar across our solar system.

The comet has witnessed a number of explosions over the past eight months, spewing out gas and dust. While such releases are not uncommon in comets, and a crescent or Pac-Man shape has been observed in other comets, it is difficult to know what is normal for Pons Brooks.

“I would say it’s somewhat unusual in terms of the number of explosions that have occurred,” Schleicher said. “On the other hand, it’s not like you have good records from the past to let you know what’s typical. And I suspect that given the fairly large number of explosions that have occurred over the past eight months, it’s pretty clear that this is a regular occurrence for Ponce Brooks.” .

Comets are pieces of dust, rock, and ice, essentially frozen remains from the formation of the solar system. They also contain freezing elements such as carbon dioxide and carbon monoxide.

Schleicher said that comets heat up and shine when they approach the sun, and some of the frozen gases stored in comets do not need to be heated much before they begin to turn into vapor.

“We think the primary driver, of course, is heating from the sun,” he said. “The comet is coming; it has been sitting in a deep freeze for years. The heat will work its way from the surface down to wherever there is carbon dioxide or carbon monoxide ice.

Astronomers suspect that the Pons-Brooks explosions occurred over recurring events, where heat vaporizes material inside the comet, causing pressure to build up and breach the surface. While the gas explosion wouldn’t be visible in telescopes, the dust kicked up from it would create the kind of events observed from Ponce Brooks, Schleicher said.

Scientists have traced jets of material observed shooting from the comet as it exploded to two source regions on its surface. Astronomers are puzzled as to why “the entire surface isn’t exploding like crazy,” Schleicher said.

Observations suggest that the ice has flaked off most of the surface, or that the ice has evaporated, leaving only dirt behind, but astronomers are “not quite sure which of these mechanisms is running the show,” he said.

Caretta said that the comet’s explosions appear to have stopped, and no explosive activity has appeared since February.

Astronomers have been observing Pons Brooks in hopes of revealing more details about its spin rate, or the rate at which comets spin as they move through space. The Pons-Brooks rotation period is 57 hours, longer than expected, and astronomers want to know whether jets of material emitted by the comet are speeding it up or slowing it down.

A series of overlapping events likely contributed to Ponce Brookes’ distinctive appearance, but it could also be due to our view of the comet, Carretta said.

“These are three-dimensional things,” Carretta said. “When we take pictures of the night sky, we take them in a limited range of colors, and they’re all flat in two dimensions. This will make things that might otherwise make perfect sense to you, if you were able to get up and walk around and see them from two different perspectives, look much more complex than they really are.”