At The Center of Everything

Vega, the fifth-brightest nighttime star, beams almost straight overhead early this month and may be the most important luminary in the sky after the Sun. But how exactly do you say its name? Is it VEE-guh or VAY-guh?

In July 2006, Sky & Telescope's Tony Flanders addressed the question:

"In 1941 the American Astronomical Society (AAS) formed a committee of Samuel G. Barton, George A. Davis, Jr., and Daniel J. McHugh to consult with astronomers, educators, Arabic scholars, and planetarium lecturers and come up with a list of preferred pronunciations for common star names and constellations. 

Their final report, adopted by the AAS, appeared in Sky & Telescope for June 1943, page 12." They decided that Vega should be pronounced VEE-guh. This made sense because for centuries it had been known as Wega and spoken as WE-guh, which means descending eagle in Arabic. 

Later, the W evolved into a V, but the pronunciation remained the same: VEE-guh. As a budding amateur astronomer in 1966, I owned an Edmund planisphere that included an instruction manual with a pronunciation guide in line with AAS standards.

Yet somewhere along the way Vega became (mostly) VAY-guh, leaving me and my ilk in the minority. Nowadays, the online Merriam-Webster dictionary gives both pronunciations, while the American Heritage Dictionary lists VEE-guh. Recognizing that language evolves, I tell newcomers to the hobby that either is correct.  READ MORE...

Zodiacal Light on Exoplanets

Watch the sun set from a particularly dark patch of Earth and you may spot a triangle of what scientists call zodiacal light extending from where our star passed below the horizon.

Zodiacal light in Earth's skies is created when sunlight bounces off the dust that fills the solar system, the remains of pulverized asteroids and flurry left by passing comets. 

And according to new research by a team of astronomers and high school students based in China, a similar phenomenon occurs in the skies of at least a few potentially habitable exoplanets. The light could be one more clue for scientists seeking to puzzle out what those exotic neighborhoods might look like.

"If we can detect zodiacal light from a distant planet system, then this system likely has components like asteroids and comets, which can't be easily detected directly in other ways," lead author Jian Ge, an astronomer at Shanghai Astronomical Observatory in China, said during a news conference held virtually on Jan. 13 by the American Astronomical Society. 

Ge had been scheduled to present the research at a meeting organized by the group that was canceled due to COVID-19.  TO READ MORE ABOUT THIS, CLICK HERE...

Giant ARC

A newly discovered crescent of galaxies spanning 3.3 billion light-years is among the largest known structures in the universe and challenges some of astronomers' most basic assumptions about the cosmos.

The epic arrangement, called the Giant Arc, consists of galaxies, galactic clusters, and lots of gas and dust. It is located 9.2 billion light-years away and stretches across roughly a 15th of the observable universe.

Its discovery was "serendipitous," Alexia Lopez, a doctoral candidate in cosmology at the University of Central Lancashire (UCLan) in the U.K., told Live Science. Lopez was assembling maps of objects in the night sky using the light from about 120,000 quasars — distant bright cores of galaxies where supermassive black holes are consuming material and spewing out energy.

As this light passes through matter between us and the quasars, it is absorbed by different elements, leaving telltale traces that can give researchers important information. In particular, Lopez used marks left by magnesium to determine the distance to the intervening gas and dust, as well as the material’s position in the night sky.

In this way, the quasars act "like spotlights in a dark room, illuminating this intervening matter," Lopez said.

In the midst of the cosmic maps, a structure began to emerge. "It was sort of a hint of a big arc," Lopez said. "I remember going to Roger [Clowes] and saying 'Oh, look at this.'"

Clowes, her doctoral adviser at UCLan, suggested further analysis to ensure it wasn't some chance alignment or a trick of the data. After doing two different statistical tests, the researchers determined that there was less than a 0.0003% probability the Giant Arc wasn't real. They presented their results on June 7 at the 238th virtual meeting of the American Astronomical Society.  TO READ MORE, CLICK HERE...