“The Devil’s Comet” will approach the Earth at its maximum distance
(CNN) — An unusual horned comet, known for a series of outbursts and nicknamed the “Devil’s Comet,” will approach Earth this Sunday around 3 a.m. ET.
While people in the Northern Hemisphere haven’t seen the comet since the first week of May, skywatchers in the Southern Hemisphere have a better chance of seeing the blurry object through binoculars or a telescope.
Why exactly a dynamic comet takes on a shape that has been compared to the Millennium Falcon spaceship from the Star Wars films when it is explosive remains a mystery to scientists. But the celestial object only takes about 71 years to orbit the Sun once, much like Halley’s Comet, making it a unique opportunity to observe it for close study.
Since the comet won’t pass Earth for several decades, collective observations by astronomers could provide key information about its true nature and behavior.
Officially known as Comet 12P/Pons-Brooks, the celestial object made its closest approach to the Sun on April 21 at a distance of 119.7 million kilometers (74.4 million miles) from our star.
On Sunday, the comet will approach Earth at its maximum distance, but it will be more than 230 million kilometers from our planet and will not pose a danger. For reference, the Sun is 149 million kilometers (93 million miles) from Earth.
The Virtual Telescope project captured the view of the comet over Manciano, in the Italian region of Tuscany, under the peninsula’s darkest sky. Gianluca Masi / Virtual Telescope Project
The comet’s brightness peaked in late April and gradually faded over three to four weeks, said Dr. Dave Schleicher, an astronomer at Lowell Observatory in Arizona.
“For people below the equator, the coming weeks and months could be the first good chance to see this since the 1950s,” said astronomer Dr. Teddy Careta, a postdoctoral fellow at Lowell.
Two prolific discoverers, Jean-Louis Pons and William Robert Brooks, independently observed Comet Diablo: Pons in 1812 and Brooks in 1883. than “something strange in the atmosphere,” Schleicher said.
Astronomers estimate the huge comet’s diameter is between 10 and 20 kilometers (6.2 and 12.4 miles), Kareta said.
The rare visitor has a green appearance, typical of most comets, because they contain diatomic carbon molecules that absorb sunlight and emit a color that appears green from our perspective, Schleicher said.
Series of cosmic explosions
Ponce Brooks recently attracted the attention of astronomers after demonstrating intriguing behavior that caused the comet to take on a horned appearance and fly through our solar system.
Over the past eight months, the comet has experienced a series of explosions that eject gas and dust. While such ejections are not uncommon for comets, and others have been observed to have crescent or Pac-Man shapes, it is difficult to say what is normal for Pons-Brooks.
“I would say it’s quite unusual because of the number of angry outbursts he had,” Schleicher said. “On the other hand, it’s not like you have good records from the past that allow you to really know what is typical. And I suspect that, given the large number of outbreaks that have occurred over the last eight months, this is clearly a common occurrence for Ponce Brooks.”
Comets are pieces of dust, rock and ice, essentially the frozen remnants of the formation of the solar system. They also contain frozen elements such as carbon dioxide and carbon monoxide.
Comets warm up and become brighter as they get closer to the sun, Schleicher said, and some of the frozen gases stored in comets don’t need to get very hot before they begin to turn to steam.
The expanding bright spot (center) is the explosion of Comet 12P/Pons Brooks, which occurred the day before the Lowell Discovery Telescope in Arizona captured this image in October 2023.
“We think the driving factor is, of course, solar-induced warming,” he said. “The comet is approaching; It has been frozen for many years. “Heat will spread from the surface to where the ice is from carbon dioxide or carbon monoxide.”
Astronomers suspect that Pons-Brookes flares occurred in repeating events in which heat vaporizes material inside the comet, causing pressure to build up and break through the surface. Although the gas explosion won’t be visible to telescopes, the dust it kicks up will create the events seen with Ponce Brooks, Schleicher said.
Scientists have traced the jets of material ejected from the comet during its explosion to two source regions on its surface. Astronomers wonder why “not the entire surface is exploding like crazy,” Schleicher said.
The observations suggest that ice has formed on much of the surface, or that the ice has evaporated leaving only dirt, but astronomers are “not entirely sure which of these mechanisms is driving the spectacle,” he said.
However, the comet’s outbursts appear to have stopped and it has not shown any activity since February, Careta said.
What we can learn from comets
Astronomers have been observing Ponce Brooks in hopes of learning more details about its rotation rate, or the speed at which comets spin as they move through space. Ponce Brooks’ rotation period is 57 hours, longer than expected, and astronomers want to know whether the jets of material released by the comet are speeding up or slowing down its rotation.
A series of overlapping events likely contributed to Ponce Brooks’ distinctive appearance, Caretta said, but it may also have something to do with how we view the comet.
“These are three-dimensional objects,” Kareta said. “When we take images of the night sky, we take them in a limited range of colors, and they’re all smoothed out in two dimensions. “It makes things that might make a lot of sense to you, if you can walk around and see them from several different perspectives, seem a lot more complex than they really are.”