Have you ever seen a star explode? You’ll soon have the chance

 

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Every clear night for three weeks, Bob Stephens has pointed his personal telescope at the same two stars in the hopes of witnessing one of the most violent events in the universe: the explosion of a nova 100,000 times brighter than the sun.

The eruption, which scientists say could occur at any time, has attracted interest from major observatories around the world and promises to advance our understanding of turbulent binary star systems.

Yet for all the high-tech observing power at NASA and other  scientific institutions, astrophysicists are relying on countless amateur astronomers like Stephens to spot the explosion first.

The reason? It’s simply too expensive to keep their equipment focused on the same subject for months on end.

“I think everybody’s going to watch what happens, but sitting there and watching it isn’t going to make it happen,” said Tom Meneghini, the telescope’s operations director and executive director emeritus of the Mount Wilson Observatory. “It’s like a watched pot,” he joked.

The star is so distant that it takes 3,000 years for its light to reach Earth, meaning the explosion occurred before the last of Egypt’s pyramids were built. It will appear about as bright as the North Star for just a few days before fading into darkness.

Once spotted, some of the most advanced observatories on Earth and in space will join us in observing it, including NASA’s James Webb Space Telescope.

“A lot of people are looking forward to seeing the new crown jewel,” said Mansi Kasliwal, a professor of  astronomy at Caltech, who plans to use the Palomar Observatory in northeastern San Diego County to observe the event. The nova will erupt in the constellation Corona Borealis.

T Coronae Borealis, also called the Blaze Star, is actually made up of two stars: a hot, dense white dwarf and a cooler red giant.

The dwarf star, which long ago ran out of fuel and collapsed to the size of Earth, has been siphoning hydrogen gas from its larger neighbor for about a human lifetime.

This stolen gas has accumulated in a disk around the dwarf, like a hot, disordered version of Saturn’s rings. Soon the disk will become so heavy that it will become violent and unwieldy, and inevitably, explode like a thermonuclear bomb.

However, neither star is destroyed and the process repeats itself approximately every 80 years.

This time, an army of enthusiasts like Stephens is ready to sound the alarm when the star goes nova.

Far from being mere amateurs, a number of these amateur observers published their own scientific research. Stephens even built his own observatory as an annex to his home in Rancho Cucamonga.

“The city thinks it’s a porch,” Stephens said. After the inspector came by, he removed the screws holding the roof in place, allowing him to roll it back to reveal the clear sky through his telescope.

Every night, he turns on the telescope and spends more than an hour collecting data, which he then posts to an online community of amateur astronomers who monitor the star almost nonstop.

Large observatories simply cannot provide such constant monitoring. Hundreds of scientists compete for time to observe a wide variety of astronomical targets each night. For them, keeping their telescopes trained on the Blaze star is a waste of valuable observing time.

Estimates of when the nova will occur vary, but most astrophysicists agree that it will occur before the end of the year, and probably by the end of August.

Once the star explodes, several alert systems are put in place to notify amateurs and professionals. Some observatories have even programmed their telescopes to autonomously abandon their current observing plan and look at the star when the notification arrives, Stephens said.

Large observatories also face another complication. Most of their telescopes are designed to observe the faintest, dimmest targets, but the Blaze Star nova will be anything but faint. Pointing these telescopes at the nova would overwhelm the sensors, resulting in a washed-out, overexposed image.

That’s why Palomar Observatory, Caltech’s research station in northern San Diego County, doesn’t use its iconic 16-foot-wide Hale telescope under its huge white dome. Instead, it uses a much smaller telescope, called the Gattini-IR, located in an unsuspecting little brick building about a quarter-mile away.

Once the nova appears, Gattini-IR will observe the Blaze star every two nights at two-hour intervals.

Scientists say there is still much to learn about novae. For example, physicists still don’t know why some novae erupt every ten years, while others don’t erupt until millennia later.

Some researchers suspect that novae such as the Blaze star may be precursors to supernovae. These explosions, billions of times brighter than the Sun, destroy the star, often leaving behind a black hole. Supernovae are also a useful tool for astronomers to measure distance.

The study of similar events has already led to discoveries.

Recently, scientists have determined that novae tend to eject matter into space at speeds faster than would be expected based on the intensity of the explosion.

“We want to understand the physics of novae, so having a nova as close as T Coronae Borealis, which will hopefully be very well studied by all the telescopes…we can get a very complete picture,” said Caltech’s Kasliwal.

Part of this understanding will be due in part to amateur astronomers.

Thanks to the rapid development of telescopes, amateurs are working with technology that professionals didn’t have even 20 years ago, let alone 80 years ago, said Forrest Sims, an amateur astronomer from Apache Junction, Ariz., who also observes the star every clear night.

And amateurs can get better coverage than large telescopes because “we usually have complete control over when and where we can point.” [our telescopes]”, Sims said. “A professional might have to write a grant application to get a half-hour or two hours of time on a large telescope.”

This allows them to collect a lot of data. And with hundreds of community members observing from around the world, they can provide near-continuous coverage of the Blaze star. Many, including Sims and Stephens, publish their data on the American Association of Variable Star Observers website, allowing anyone to use the data.

Stephens remembers reading a journal article by a professional who had managed to observe five asteroids in two years. “I thought I could do that in a month,” Stephens said. He later published a paper with 10 observations.

One professor was so shocked by the number of telescopes Stephens could see that she agreed to travel to Puerto Rico for an asteroid conference, just to meet him. They ended up working together: Stephens had the telescopes, she had the connections in the field.

Today, the work of amateur astronomers is becoming so sophisticated that many find it difficult to call them amateurs.

“We call ourselves ‘scientists working on small telescopes,’” Sims says. “It sounds more fun, and in some ways professionals – and not even grudgingly – will admit that the work we do is often professional-level.”

Los Angeles Times 2024. Distributed by Tribune Content Agency, LLC.

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