binary stars Archives

February 4, 2022February 4, 2022 by Evan Gough

A Second Generation of Planets can Form Around a Dying Star

An illustration of a protoplanetary disk. The solar system formed from such a disk. Astronomers suggest this birthplace was protected by a larger filament of molecular gas and dust early in history. Credit: NASA/JPL-Caltech/T. Pyle (SSC)

When young stars coalesce out of a cloud of molecular hydrogen, a disk of leftover material called a protoplanetary disk surrounds them. This disk is where planets form, and astronomers are getting better at peering into those veiled environments and watching embryonic worlds take shape. But young stars aren’t the only stars with disks of raw material rotating around them.

Some old, dying stars also have disks. Can a second generation of planets form under those conditions?

January 26, 2022January 26, 2022 by Evan Gough

Incredible Image Shows Twin Stellar Jets Blasting Out of a Star-Forming Region

The sinuous young stellar jet, MHO 2147, meanders lazily across a field of stars in this image captured from Chile by the international Gemini Observatory, a Program of NSF's NOIRLab. The stellar jet is the outflow from a young star that is embedded in an infrared dark cloud. Astronomers suspect its sidewinding appearance is caused by the gravitational attraction of companion stars. These crystal-clear observations were made using the Gemini South telescope’s adaptive optics system, which helps astronomers counteract the blurring effects of atmospheric turbulence. Image Credit: International Gemini Observatory/NOIRLab/NSF/AURA

Young stars go through a lot as they’re being born. They sometimes emit jets of ionized gas called MHOs—Molecular Hydrogen emission-line Objects. New images of two of these MHOs, also called stellar jets, show how complex they can be and what a hard time astronomers have as they try to understand them.

January 7, 2022January 7, 2022 by Evan Gough

Astronomers Discover a Totally New Kind of Nebula

Discovery image of the nebula. For this image, 120 individual exposures had to be combined to obtain a total exposure time of 20 hours. The images were taken over several months from Brazil. Image Credit: Maicon Germiniani

Most Universe Today readers are familiar with nebulae. They’re gaseous structures lit up with radiation from nearby stars, and they’re some of nature’s most beautiful forms.

With the help of amateur astronomers who laid the groundwork, an international team of astronomers have discovered a new type of nebulae around binary stars that they’re calling galactic emission nebulae.

December 17, 2021December 17, 2021 by Evan Gough

Astronomers See a Star Crash Through the Planetary Disk of Another Star

Flash heating around the second star after it has crashed through the disc. FU Ori. Credit: Elisabeth Borchert.

What causes an otherwise unremarkable star to become over 100 times brighter? That’s a question astronomers have been pondering since 1936, when a star in Orion brightened from 16th magnitude to 8th magnitude in a single year.

The star, named FU Ori, is still bright to this day. Astronomers have come up with different explanations for the star’s brightening, but none of them provides a complete explanation.

Now we might have one.

September 7, 2021September 7, 2021 by Paul M. Sutter

Many Sunlike Stars Gobbled up Some of Their Planets

New research shows that other sunlike stars in our galaxy aren’t so kind to their planets. Up to a quarter of them may consume planets before they even establish a solar system. That consumption leaves behind a distinct chemical fingerprint in the stars, which can help researchers understand how common planetary systems are…and how often they get destroyed.

July 12, 2021July 12, 2021 by Matt Williams

A Nearby White Dwarf Might be About to Collapse Into a Neutron Star

About 97% of all stars in our Universe are destined to end their lives as white dwarf stars, which represents the final stage in their evolution. Like neutron stars, white dwarfs form after stars have exhausted their nuclear fuel and undergo gravitational collapse, shedding their outer layers to become super-compact stellar remnants. This will be the fate of our Sun billions of years from now, which will swell up to become a red giant before losing its outer layers.

Unlike neutron stars, which result from more massive stars, white dwarfs were once about eight times the mass of our Sun or lighter. For scientists, the density and gravitational force of these objects is an opportunity to study the laws of physics under some of the most extreme conditions imaginable. According to new research led by researchers from Caltech, one such object has been found that is both the smallest and most massive white dwarf ever seen.

July 8, 2021July 8, 2021 by Matt Williams

There are Probably Many More Earth-Sized Worlds Than Previously Believed

This illustration depicts a planet partially hidden in the glare of its host star and a nearby companion star. After examining a number of binary stars, astronomers have concluded that Earth-sized planets in many two-star systems might be going unnoticed by transit searches, which look for changes in the light from a star when a planet passes in front of it. The light from the second star makes it more difficult to detect the changes in the host star’s light when the planet passes in front of it. Credit: International Gemini Observatory/NOIRLab/NSF/AURA/J. da Silva (Spaceengine)

In the past decade, the discovery of extrasolar planets has accelerated immensely. To date, 4,424 exoplanets have been confirmed in 3,280 star systems, with another 7,453 awaiting confirmation. So far, most of these planets have been gas giants, with about 66% being similar to Jupiter or Neptune, while another 30% have been giant rocky planets (aka. “Super-Earths). Only a small fraction of confirmed exoplanets (less than 4%) have been similar in size to Earth.

However, according to new research by astronomers working at NASA Ames Research Center, it is possible that Earth-sized exoplanets are more common than previously thought. As they indicated in a recent study, there could be twice as many rocky exoplanets in binary systems that are obscured by the glare of their parent stars. These findings could have drastic implications in the search for potentially habitable worlds since roughly half of all stars are binary systems.

June 19, 2021June 19, 2021 by Andy Tomaswick

Astronomers Find a Blinking Star Near the Center of the Milky Way

In this week’s edition of new unexplained astronomical phenomena, a team of astronomers led by Dr. Leigh Smith from Cambridge found a star 100 times larger than our sun that nearly disappears from the sky every few decades. They also have no idea why it does so.

April 27, 2021April 27, 2021 by Brian Koberlein

Smallest, Closest Black Hole Ever Discovered is Only 1,500 Light-Years Away

Artist concept of V723 Mon and its companion. Lauren Fanfer/Ohio State

In theory, a black hole is easy to make. Simply take a lump of matter, squeeze it into a sphere with a radius smaller than the Schwarzschild radius, and poof! You have a black hole. In practice, things aren’t so easy. When you squeeze matter, it pushes back, so it takes a star’s worth of weight to squeeze hard enough. Because of this, it’s generally thought that even the smallest black holes must be at least 5 solar masses in size. But a recent study shows the lower bound might be even smaller.

February 24, 2021February 24, 2021 by Scott Alan Johnston

Our Part of the Galaxy is Packed with Binary Stars

Binary star systems are everywhere. They make up a huge percentage of all known solar systems: from what we can tell, about half of all Sun-like stars have a binary partner. But we haven’t really had a chance to study them in detail yet. That’s about to change. Using data from the European Space Agency’s Gaia spacecraft, a research team has just compiled a gigantic new catalog of nearby binary star systems, and it shows that at least 1.3 million of them exist within 3000 light-years of Earth.