ALMA tagged posts

ALMA uncovers sulfur for the first time around a rare class of supergiant star

Astronomers have discovered a chemically rich collection of sulfur-bearing molecules surrounding the rare massive star HD 87643. The observations include the first detection of sulfur monoxide and sulfur dioxide around a B[e] supergiant. The paper was published in The Astrophysical Journal Letters on July 1.

Rare and old
B[e] supergiants, or sgB[e], are rare, evolved massive stars that have moved past their main hydrogen-burning phase. They are notable for distinctive emission lines—hence the “[e]” in their name—including rare “forbidden” lines produced by the surrounding gas and dust, along with an infrared glow far more intense than that of ordinary B-type stars.

As these stars approach the final stages of their lives, they shed enormous amounts of material, building up mes...

Read More

These ancient quasars shouldn’t exist so soon after the Big Bang

An artist's concept of a distant galaxy with an active quasar at its center shooting out bright jets of radiation above and below the galactic disc.
Photo Credit
NASA, ESA, Joseph Olmsted (STScI)

Scientists have found the oldest quasars ever seen, revealing giant black holes blazing across the universe when it was only 670 million years old. Astronomers have uncovered 31 of the oldest known quasars, including the two earliest ever detected, shining from a time when the universe was only about 670 million years old. Powered by supermassive black holes billions of times the Sun’s mass, these incredibly bright objects challenge scientists’ understanding of how such enormous black holes formed so quickly after the Big Bang.

Quasars rank among the brightest and most powerful objects in the universe...

Read More

Two blazing quasars caught waltzing into a merger

Two blazing quasars caught waltzing into a merger
Artist’s concept of two quasars in the process of merging. Credit: International Gemini Observatory/NOIRLab/NSF/AURA/M. Garlick

Astronomers, using the Atacama Large Millimeter/submillimeter Array (ALMA), have confirmed the existence of a close quasar pair housed in a pair of merging galaxies seen when the universe was less than a billion years old, at a redshift of 5.7. The system, designated J2037–4537, is one of only two confirmed quasar pairs at redshift greater than 5 ever found. A paper outlining this work was submitted to the preprint server arXiv on April 7.

Quasars are among the most luminous objects in the universe. They belong to the family of active galactic nuclei (AGN)—galaxies that are powered by supermassive black holes at their centers...

Read More

3I/ATLAS contains 30 times more semi-heavy water than comets in our solar system

This artist’s impression compares the semi-heavy water content of the interstellar comet 3I/ATLAS (left) and Earth (right). Insets illustrate the relative abundance of deuterated water (HDO) molecules, showing that 3I/ATLAS contains over 30 times more HDO than is found in Earth’s oceans. This elevated ratio suggests the comet formed in an extremely cold environment, very different from the conditions that shaped our Solar System.
Credit: NSF/AUI/NSF NRAO/M.Weiss

New observations of the interstellar comet 3I/ATLAS include the first measurement of the abundance of deuterated water relative to ordinary water in an interstellar object...

Read More