Birth of a star predicted

Jun 09, 2009

The astrophysicist João Alves, director of the Calar Alto Observatory in Almeria, and his colleague Andreas Bürkert, from the German observatory in the University of Munich, believe that "the inevitable future of the starless cloud Barnard 68" is to collapse and give rise to a new star, according to an article which has been published recently in The Astrophysical Journal.

Barnard 68 (B68) is a dark nebula located in the constellation of Ofiuco, around 400 light years away. Nebulae are interstellar clouds of dust and gas located within the Milky Way, and some of these are the so-called 'dark' nebulae, the silhouettes of which block out the light of the stars and other objects behind them.

Scientists believe that stars are formed inside nebulae. The most commonly-held theory by astronomers is that they form from the condensation of giant gas clouds as a result of their own gravity, until this reaches a point where the high density and temperatures lead to nuclear fusion that results in the formation of a star. This is the most widely accepted theory among astronomers, although many details of the process are still not understood. The new study may be able to shed some light on this.

The astrophysicists Alves and Bürkert suggest that the collision of two gas clouds could be the mechanism that activates the birth of a star. In relation to Barnard 68, they suggest that it is already in an initial unstable state, and that it will collapse "soon" - within a period of around 200,000 years.

The images they have taken of its density show that B68 is a cold gas cloud with a mass equivalent to that of two suns, but that there is another cloud, 10 times smaller than it (0.2 solar masses), which is getting closer and is "on the verge" of colliding with it.

In order to prove their theory, the two astrophysicists have simulated this scenario in a supercomputer at the University of Munich. Based on the theoretical models, they introduced data relating to two globules separated by one light year, with masses and speeds similar to those of the Barnard 68 nebula and its "small" companion. By using a numerical algorithm, the researchers were able to show how these two virtual gas clouds evolved over time.

The Sun will get a new neighbour

The results showed that the smaller globule penetrated the larger one after around 1.7 million years at a speed of 370 metres per second. The model also showed that the stability of the initial situation declined over time. At the moment when the two globules merged, enormous densities were generated, making the system collapse and creating the ideal conditions for the formation of a star.

The researchers carried out various simulations, varying the physical parameters of the globules, until they could work out the circumstances in which the fusion of two gas clouds will lead to their subsequent collapse. According to Bürkert and Alves' calculations, a new star will form within 200,000 years, not very far from our solar system, with the potential for planets to be formed around it.

Source: Spanish Foundation for Science and Technology

Explore further: A star's early chemistry shapes life-friendly atmospheres

add to favorites email to friend print save as pdf

Related Stories

Small 'helper' stars needed for massive star formation

Feb 28, 2008

In order for a rare, massive star to form inside an interstellar cloud of gas and dust, small "helper" stars about the size of the sun must first set the stage, according to a new theory proposed by astrophysicists at the ...

Turbulence May Promote the Birth of Massive Stars

Feb 23, 2009

(PhysOrg.com) -- On long, dark winter nights, the constellation of Orion the Hunter dominates the sky. Within the Hunter's sword, the Orion Nebula swaddles a cluster of newborn stars called the Trapezium. These stars are ...

AKARI's view on birth and death of stars

Aug 28, 2006

AKARI, the Japan Aerospace Exploration Agency (JAXA) infrared astronomical satellite with ESA participation, is continuing its survey of the sky and its mapping of our cosmos in infrared light. New exciting ...

Recommended for you

Professional and amateur astronomers join forces

2 hours ago

(Phys.org) —Long before the term "citizen science" was coined, the field of astronomy has benefited from countless men and women who study the sky in their spare time. These amateur astronomers devote hours ...

A star's early chemistry shapes life-friendly atmospheres

Apr 23, 2014

Born in a disc of gas and rubble, planets eventually come together as larger and larger pieces of dust and rock stick together. They may be hundreds of light-years away from us, but astronomers can nevertheless ...

Image: X-raying the cosmos

Apr 22, 2014

When we gaze up at the night sky, we are only seeing part of the story. Unfortunately, some of the most powerful and energetic events in the Universe are invisible to our eyes – and to even the best optical ...

Mysteries of nearby planetary system's dynamics solved

Apr 22, 2014

Mysteries of one of the most fascinating nearby planetary systems now have been solved, report authors of a scientific paper to be published by the journal Monthly Notices of the Royal Astronomical Society in its ...

User comments : 0

More news stories

Habitable exoplanets are bad news for humanity

Last week, scientists announced the discovery of Kepler-186f, a planet 492 light years away in the Cygnus constellation. Kepler-186f is special because it marks the first planet almost exactly the same size as Earth ...

Professional and amateur astronomers join forces

(Phys.org) —Long before the term "citizen science" was coined, the field of astronomy has benefited from countless men and women who study the sky in their spare time. These amateur astronomers devote hours ...

First-of-its-kind NASA space-weather project

A NASA scientist is launching a one-to-two-year pilot project this summer that takes advantage of U.S. high-voltage power transmission lines to measure a phenomenon that has caused widespread power outages ...