ALMA Observatory Archives

September 3, 2024September 3, 2024 by Evan Gough

This Ancient Galaxy Merger Will Produce a very Luminous Quasar

This illustration depicts two quasars in the process of merging. There are many unanswered questions around galaxy mergers and the quasars that can result. Image Credit: NOIRLab/NSF/AURA/M. Garlick)

In the contemporary Universe, massive galaxies are plentiful. But the Universe wasn’t always like this. Astronomers think that galaxies grew large through mergers, so what we see in space is the result of billions of years of galaxies merging. When galaxies merge, the merger can feed large quantities of gas into their centers, sometimes creating a quasar.

Much of this is theoretical and shrouded in mystery, but astronomers might have found evidence of a galaxy merger creating a quasar.

August 5, 2024August 5, 2024 by Mark Thompson

Astronomers See Planets Forming Around Binary Stars

Artist's illustration of binary star planet formation. Credit: S. Dagnello, NSF/AUI/NRAO

Over 5,000 exoplanets have been discovered around distant star systems. Protoplanetary disks have been discovered too and it’s these, out of which all planetary systems form. Such disks have recently been found in two binary star systems. The stellar components in one have a separation of 14 astronomical units (the average distance between the Earth and Sun is one astronomical unit) and the other system has a separation of 22 astronomical units. Studying systems like these allow us to see how the stars of a binary system interact and how they can distort protoplanetary disks.

August 1, 2024August 1, 2024 by Evan Gough

A New Model Explains How Gas and Ice Giant Planets Can Form Rapidly

Artist's impression of a young star surrounded by a protoplanetary disc made of gas and dust. According to new research, ring-shaped, turbulent disturbances (substructures) in the disk lead to the rapid formation of several gas and ice giants. Credit: LMU / Thomas Zankl, crushed eyes media

The most widely recognized explanation for planet formation is the accretion theory. It states that small particles in a protoplanetary disk accumulate gravitationally and, over time, form larger and larger bodies called planetesimals. Eventually, many planetesimals collide and combine to form even larger bodies. For gas giants, these become the cores that then attract massive amounts of gas over millions of years.

But the accretion theory struggles to explain gas giants that form far from their stars, or the existence of ice giants like Uranus and Neptune.

July 30, 2024July 30, 2024 by Evan Gough

No Merger Needed: A Rotating Ring of Gas Creates A Hyperluminous Galaxy

This is a distant Hyper Luminous Infrared Galaxy named PJ0116-24. These galaxies experience rapid star formation that astronomers think is triggered by mergers. But this one suggests otherwise. Warm gas is shown in red and cold gas is shown in blue. Image Credit: PJ0116-24

Some galaxies experience rapid star formation hundreds or even thousands of times greater than the Milky Way. Astronomers think that mergers are behind these special galaxies, which were more abundant in the earlier Universe. But new results suggest no mergers are needed.

May 15, 2024May 15, 2024 by Evan Gough

A Star Became 1,000 Times Brighter, and Now Astronomers Know Why

Artist’s impression of one of the two stars in the FU Orionis binary system, surrounded by an accreting disk of material. What has caused this star — and others like it — to dramatically brighten? [NASA/JPL-Caltech] — Artist’s impression of one of the two stars in the FU Orionis binary system, surrounded by an accreting disk of material. Credit: NASA/JPL-Caltech

Astronomers were surprised in 1937 when a star in a binary pair suddenly brightened by 1,000 times. The pair is called FU Orionis (FU Ori), and it’s in the constellation Orion. The sudden and extreme variability of one of the stars has resisted a complete explanation, and since then, FU Orionis has become the name for other stars that exhibit similar powerful variability.

April 9, 2024April 9, 2024 by Evan Gough

If Europa has Geysers, They’re Very Faint

Jupiter's second Galilean moon, Europa. Its smooth surface has fewer craters than other moons, but they help us understand its icy shell. (Credit: NASA/JPL/Galileo spacecraft) — The Hubble spotted evidence of geysers coming from Jupiter's moon Europa, but nobody's been able to find them again. (Credit: NASA/JPL/Galileo spacecraft)

In 2013, the Hubble Space Telescope spotted water vapour on Jupiter’s moon Europa. The vapour was evidence of plumes similar to the ones on Saturn’s moon Enceladus. That, and other compelling evidence, showed that the moon has an ocean. That led to speculation that the ocean could harbour life.

But the ocean is obscured under a thick, global layer of ice, making the plumes our only way of examining the ocean. The plumes are so difficult to detect they haven’t been confirmed.

March 12, 2024March 12, 2024 by Evan Gough

Astronomers Propose a 50-Meter Submillimeter Telescope

The Atacama Large Millimeter/submillimeter Array (ALMA) in northern Chile is our most powerful radio telescope. But astronomers are hungering for a new radio telescope made of one massive dish. Image Credit: A. Marinkovic/X-Cam/ALMA (ESO/NAOJ/NRAO)

Some parts of the Universe only reveal important details when observed in radio waves. That explains why we have ALMA, the Atacama Large Millimetre-submillimetre Array, a collection of 7-meter and 12-meter radio telescopes that work together as an interferometer. But, ALMA-type arrays have their limitations, and astronomers know what they need to overcome those limitations.

They need a radio telescope that’s just one single, massive dish.

March 8, 2024March 8, 2024 by Nancy Atkinson

Astronomers Image 62 Newly-Forming Planetary Systems

Planet-forming discs in three clouds of the Milky Way. Credit: ESO.

Astronomers using the Very Large Telescope in Chile have now completed one of the largest surveys ever to hunt for planet-forming discs. They were able to find dozens of dusty regions around young stars, directly imaging the swirling gas and dust which hints at the locations of these new worlds.

Just like the wide variety in the types of exoplanets that have been discovered, these new data and stunning images show how protoplanetary systems are surprisingly diverse, with different sizes and shapes of disks.

In research presented in three new papers, researchers imaged 86 young stars and found 62 of them had a wide range of star-forming regions surrounding them. The astronomers say this study provides a wealth of data and unique insights into how planets arise in different regions of our galaxy.

January 19, 2024January 19, 2024 by Evan Gough

Astronomers See Massive Stars Forming Together in Multiple Star Systems

This false-color image of the massive star formation region G333.23–0.06 came from data obtained with the ALMA radio observatory. The insets show regions where researchers detected multiple systems of protostars. The star symbols indicate the location of each newly forming star. Image Credit: S. Li, MPIA / J. Neidel, MPIA Graphics Department / Data: ALMA Observatory

All stars form in giant molecular clouds of hydrogen. But some stars are extraordinarily massive; the most massive one we know of is about 200 times more massive than the Sun. How do these stars gain so much mass?

Part of the answer is that they form in multiple star systems.

January 10, 2024January 10, 2024 by Evan Gough

The Youngest Planetary Disks Ever Seen

The evolutionary sequence of protoplanetary disks with substructures, from the ALMA CAMPOS survey. These wide varieties of planetary disk structures are possible formation sites for young protoplanets. Image Credit: Hsieh et al. in prep.

How long does planet formation take? Maybe not as long as we thought, according to new research. Observations with the Atacama Large Millimetre/submillimetre Array (ALMA) show that planet formation around young stars may begin much earlier than scientists thought.