A giant, hissing planet may orbit the star Vega

Astronomers have discovered new tips from a giant, scorching hot planet orbiting Vega, one of the brightest stars in the night sky.

The research, conducted this month in The Astrophysical Journal, led by the University of Colorado, Boulder student Spencer Hurt, an undergraduate student in the Department of Astrophysical and Planetary Sciences.

It focuses on an iconic and relatively young star, Vega, who is part of the constellation Lyra and has a mass that is twice as much as our own sun. This celestial body lies only 25 light-years, or about 150 trillion miles, from Earth – astronomically speaking.

Scientists can also see Vega with telescopes, even if it is not light, making it an excellent candidate for research, co-author Samuel Quinn said.

“It’s bright enough that you can observe it at dusk when other stars are washed out by sunlight,” said Quinn, an astronomer at the Harvard and Smithsonian Center for Astrophysics (CfA).

Despite the star’s fame, researchers have yet to find a single planet in orbit around Vega. That may soon change: based on a decade of ground-based observations, Hurt, Quinn, and their colleagues have unearthed a curious signal that could be the star’s first known world.

If the team’s findings were found, the alien planet would orbit so close to Vega that its years would last less than two and a half Earth days. (Mercury, on the other hand, takes 88 days to orbit the sun). This candidate planet can also be considered the second hottest world in science – with surface temperatures averaging 5,390 degrees Fahrenheit.

Hurt said the group’s research also helps limit where other exotic worlds hide in the Vega area.

“It’s a massive system, much larger than our own solar system,” Hurt said. “There could be other planets in the whole system. It’s just a question of whether we can detect it.”

Youth energy

Quinn would like to try. Scientists have so far discovered more than 4,000 exoplanets or planets outside the Earth’s solar system. Few of them, however, are circular stars that are as bright or as close to Earth as Vega. This means that if there are planets around the star, scientists can examine them thoroughly.

“It will be really exciting to find a planet around Vega because it offers possibilities for future characterization in ways that planets around fainter stars would not do,” Quinn said.

There is only one catch: Vega scientists call an A-star, the name for objects that rotate bigger, younger and faster than our own sun. Vega, for example, rotates around its axis once every 16 hours – much faster than the sun with a rotation period clocking in at 27 Earth days. According to Quinn, such a lightning-fast pace could make it difficult for scientists to gather accurate data about the star’s motion and added any planets in orbit around it.

To tackle the game of heavenly hide-and-seek, he and colleagues went through about ten years of information about Vega collected by the Fred Lawrence Whipple Observatory in Arizona. The team in particular was looking for a signal from an alien planet – a slight giggle in the speed of the star.

“If you have a planet around a star, it can pull at the star so that it can waver back and forth,” Quinn said.

Hot and puffy

The search has paid off, says Hurt, who began the study as a summer research fellow working for Quinn at the CfA. The team discovered a signal indicating that Vega may be hosting what astronomers call a ‘hot Neptune’ or ” hot Jupiter ‘.

“It would be at least the size of Neptune, possibly as large as Jupiter and would be closer to Vega than Mercury is to the Sun,” Hurt said.

That close to Vega, he added, could inflate the candidate world like a balloon, and even iron would melt into gas in its atmosphere.

The scientists have a lot more work to do before they can definitively say that they have discovered this sobbing planet. Hurt noted that the easiest way to look for it is to scan the galaxy directly to search for the light of the warm, bright planet.

For now, the student is excited to see how his hard work is reflected in the constellations: ‘When I go outside and look at the night sky and see Vega, I say’ Hey, I know the star. ‘