* Astronomy

Blobrana · L

Chi Cygni

Blobrana · L

Chi Cygni Mira type variable star at maxima in the constellation Cygnus.


Date 24.07.15

Blobrana · L

HIP 97629

Blobrana · L

khi Cygni

Blobrana · L

HD 187796

Blobrana · L

RE: Chi Cygni

Blobrana · L

Dying star gives sneak peek of sun's demise

Chi Cygni, a red giant star, is nearing the end of its life. As it runs out of fuel, it pulses in and out, beating like a giant heart and ejecting shells of material. A preview of what's in store for our sun is in view across the galaxy, as a similar star balloons in its dying throes.
Read more

Blobrana · L

The death of a star: the destiny of our Sun

En obtenant l'image de l'étoile Mira Chi-Cygni en interférométrie infrarouge, une équipe menée par des astronomes de l'Observatoire de Paris a montré comment le diamètre de l'étoile oscille, et a révélé la présence et le mouvement d'une couche moléculaire chaude. Le rayon de l'étoile a une valeur moyenne de 12,1 milli arcseconde et une pulsation d'amplitude 5,1 milli arcseconde. En parallèle, l'équipe a mesuré la vitesse radiale de la couche moléculaire, qui apparaît en chute libre pendant une partie du mouvement. Ceci permet de déterminer la masse de l'étoile qui est de 2 masses solaires.
Read more (French)

Blobrana · L

Chi Cygni expands and dims, and then contracts and brightens over 408 days

Click to Play | View Details

Blobrana · L

About 550 light-years from Earth, a star like our Sun is writhing in its death throes. Chi Cygni has swollen in size to become a red giant star so large that it would swallow every planet out to Mars in our solar system. Moreover, it has begun to pulse dramatically in and out, beating like a giant heart. New close-up photos of the surface of this distant star show its throbbing motions in unprecedented detail.

"This work opens a window onto the fate of our Sun five billion years from now, when it will near the end of its life" - lead author Sylvestre Lacour of the Observatoire de Paris.

As a sunlike star ages, it begins to run out of hydrogen fuel at its core. Like a car running out of gas, its "engine" begins to splutter. On Chi Cygni, we see those splutterings as a brightening and dimming, caused by the star's contraction and expansion. Stars at this life stage are known as Mira variables after the first such example, Mira "the Wonderful," discovered by David Fabricius in 1596. As it pulses, the star is puffing off its outer layers, which in a few hundred thousand years will create a beautifully gleaming planetary nebula.

Read more