Stellar evolution tagged posts

Beehive Cluster. Credit: Sven Kohle and Till Credner

Astronomers have detected a new low-mass eclipsing binary star in an open cluster named NGC 2632, better known as the Beehive Cluster (or Praesepe). The newly identified binary, designated PTFEB132.707+19.810, contains two late-type stars much smaller and less massive than the sun.

NGC 2632 is an open star cluster that looks like a hive of bees in the constellation Cancer. Located some 577 light years away, it is one of the nearest open clusters to the solar system. Due to its proximity, this cluster is the target of numerous observations conducted by astronomers searching for new objects, including eclipsing binaries. Such binaries could be very helpful in improving our known theoretical stellar evolution models.

Although PTFEB132...

This Hubble Space Telescope image shows Supernova 1987A within the Large Magellanic Cloud, a neighboring galaxy to our Milky Way. Credit: NASA, ESA, R. Kirshner (Harvard-Smithsonian Center for Astrophysics and Gordon and Betty Moore Foundation), and M. Mutchler and R. Avila (STScI)

3 decades ago, astronomers spotted one of the brightest exploding stars in more than 400 years. The titanic supernova, called Supernova 1987A (SN 1987A), blazed with the power of 100 million suns for several months following its discovery on Feb. 23, 1987. Since that first sighting, SN 1987A has continued to fascinate astronomers with its spectacular light show...

Globular cluster M4. Credit: NOAO/AURA/NSF

Using recent advancements in Australian telescope tech, a Monash Uni team has made an unexpected discovery that a large group of stars are dying prematurely, challenging our accepted view of stellar evolution revealing that large numbers of helium burning stars are dying prematurely in the M4 globular cluster. M4 is one of the closest and brightest globular clusters, and has already been very well studied. “Globular clusters are some of the oldest objects in the Universe. Although we have some ideas for what is going on in them, every time we look carefully we find something unexpected” said Professor Lattanzio.

Researchers used a new instrument called a high efficiency and resolution multi-element spectrograph (HERMES)...

Left: Chart of nuclides and important astrophysical reactions. Right: SOHO-EIT image from 14 September 1997 showing a huge eruptive prominence in the resonance line of singly ionized helium (He II) at 304 Angstroms in the extreme ultraviolet. The material in the eruptive prominence is at temperatures of 60,000 – 80,000 K, much cooler than the surrounding corona, which is typically at temperatures above 1 million K. Credit: Image courtesy of Texas A&M Cyclotron Institute and NASA

How old is the universe? What causes a star to catastrophically explode? Answering these and other questions about stellar evolutions requires knowing the rates of the reactions involved...