Tag Archives: Betelgeuse

Betelgeuse might have eaten a star

Because the red giant star Betelgeuse rotates far faster than it should, astronomers are now theorizing that when it expanded into its present red giant phase about 100,000 years ago it swallowed a companion star which contributed its own angular momentum to the system to speed up the rotation.

This theory is bolstered by evidence of a shell of matter surrounding Betelgeuse that is possibly a remnant of that destroyed star.

Betelgeuse baffles astronomers

The uncertainty of science: New data of the red giant star Betelgeuse says that the star simply doesn’t have the energy to eject the large amount of gas it routinely blows into space.

“[W]e now have a problem”, says Graham Harper, an astrophysicist at the University of Colorado Boulder. “If you’re going to eject matter you have to put energy in, and we’re not seeing that.” Harper and his colleagues used the US–German Stratospheric Observatory for Infrared Astronomy (SOFIA), a 2.5-metre telescope that flies in a modified Boeing 747 aeroplane, to take Betelgeuse’s temperature. They found that the star’s upper atmosphere was much cooler than expected — so cool, in fact, that it doesn’t seem to have enough energy to kick gas out of its gravitational pull and into space.

“This challenges all our theoretical models,” Harper said on 7 January at a meeting of the American Astronomical Society in Kissimmee, Florida. [emphasis mine]

The data suggests the temperature of the ejected gas to be only about 512 degrees Fahrenheit. This is far too cool to fit any theory for explaining the vast amounts of gas that the star routinely puffs into space. It also suggests, not surprisingly, that scientists do not yet have a enough information to develop a clear understanding of stellar evolution. They have enough information to form rough theories, but there is still much too much they do not know.

A new infrared image of Betelgeuse suggests the star and its winds will smash into the interstellar medium in only a few thousand years.

Crash! Boom! A new infrared image of Betelgeuse suggests the star and its winds will smash into the interstellar medium in only a few thousand years.

If the bar [of gas] is a completely separate object, then taking into account the motion of Betelgeuse and its arcs and the separation between them and the bar, the [star’s] outermost arc will collide with the bar in just 5000 years, with the red supergiant star itself hitting the bar roughly 12 500 years later.

Want to see an asteroid eclipse a star?

transit of Betelgeuse

On January 2, 2012, an asteroid is going to transit across the face of Betelgeuse. And if you live in Europe, own a very sensitive telescope, look close and don’t blink, you might be able to see it!

This is all according to a preprint paper published today on the Los Alamos astro-ph preprint website, written by scientist Costantino Sigismondi of the Galileo Ferraris Institute and International Center for Relativistic Astrophysics in Rome. You can download the paper here [pdf].

The transit itself will only last 3.6 seconds, and will only be visible along a narrow swath crossing southern India and moving across the Middle East, through parts of Italy, France, and the southwestern most tips of England and Ireland. A map of this path is below the fold.
» Read more