-
15th March 2015 19:48
Link to Post #1
Space's 10 Most Mysterious Stars
Space's 10 Most Mysterious Stars
1. HD 140283, informally nicknamed Methuselah star, lies 190.1 light-years away and is one of the closest Population II stars to us. The star could be as old as 14.5 billion years (plus or minus 0.8 billion years), which at first glance would make it older than the universe's calculated age of about 13.8 billion years.
-------------------------------------------------------------------------------------------------
2. What sets SGR 0418+5729 apart from other magnetars is that careful monitoring over a span of 490 days has revealed no detectable decrease in its rotation rate. Researchers were able to make an accurate estimate of the strength of the external magnetic field. “The spectral data [...] allowed us to finally make the first detailed measurements of the magnetic field of a magnetar, confirming it as one of the largest values ever measured in the Universe” (Norbert Schartel, ESA’s XMM-Newton Project Scientist).
-------------------------------------------------------------------------------------------------
3. In January 2002, V838 Monocerotis suddenly became 600,000 times more luminous than our Sun, temporarily making it the brightest star in our Milky Way galaxy. The reason for the outburst is still uncertain, but several conjectures have been put forward, including an eruption related to stellar death processes and a merger of a binary star or planets. By 2009 its temperature had increased to 3,270 K and its luminosity was 15,000 times solar, but its radius had decreased to 380 times that of the Sun although the ejecta continues to expand.
-------------------------------------------------------------------------------------------------
4. LRLL 54361 is thought to be a binary protostar producing strobe-like flashes, located in the constellation Perseus in the star-forming region IC 348 and 950 light-years away. The object emits a burst of light every 25.34 days. The flashes may be the result of large amounts of matter falling into the growing protostars.
Last edited by Atlas; 15th March 2015 at 19:58.
-
The Following 15 Users Say Thank You to Atlas For This Post:
Agape (15th March 2015), Alekahn2 (15th March 2015), Bob (16th March 2015), Cidersomerset (15th March 2015), DeDukshyn (15th March 2015), ghostrider (15th March 2015), Hod8 (15th March 2015), Lifebringer (15th March 2015), mab777 (15th March 2015), Octavusprime (16th March 2015), ponda (15th March 2015), Richard S. (16th March 2015), seko (15th March 2015), Stephanie (15th March 2015), Ulyse30 (15th March 2015)
-
15th March 2015 19:49
Link to Post #2
Re: Space's 10 Most Mysterious Stars
-------------------------------------------------------------------------------------------------
5. V886 Centauri is the most massive pulsating white dwarf currently known. Located 50 light-years away from Earth, the star is a chunk of crystallized carbon that weighs 5 million trillion trillion pounds. That would equal a diamond of 10 billion trillion trillion carats.
-------------------------------------------------------------------------------------------------
6. SAO 206462 attracted attention because it has a circumstellar disk--that is, a broad disk of dust and gas surrounding the star. Theoretical models show that a single embedded planet may produce a spiral arm on each side of a disk. The structures around SAO 206462, however, do not form a matched pair, suggesting the presence of two unseen worlds, one for each arm.
-------------------------------------------------------------------------------------------------
7. Cygnus X-3 is a microquasar and a very bright radio source that undergoes massive flares from time to time. These flares are of unknown origin, but they are exceedingly violent events. Naval Research Laboratory observations in October 1982 using the Very Large Array detected the shock wave from a flare; it was expanding at roughly one-third the speed of light.
-------------------------------------------------------------------------------------------------
8. Though Jabbah (Nu Scorpii) appears to be a single star, it is actually a whole system of stars (possibly as many as seven), each of which is many times more massive, larger, hotter and more luminous than the sun. The Jabbah system is located about 440 light-years away from us.
-------------------------------------------------------------------------------------------------
9. 90377 Sedna is one of the most distant known objects in the Solar System other than long-period comets. Sedna's exceptionally long and elongated orbit, taking approximately 11,400 years to complete, and distant point of closest approach to the Sun, at 76 AU, have led to much speculation about its origin.
-------------------------------------------------------------------------------------------------
10. AE Aquarii is a cataclysmic variable binary star consisting of an ordinary star in a close orbit around a magnetic white dwarf. The white dwarf has the shortest known spin period of any white dwarf, completing a full revolution every 33.08 seconds. Mass is being lost from the secondary star, most of which is being flung out of the system by the rapidly spinning magnetic primary. The X-ray luminosity is likely being caused by the accretion of mass onto the white dwarf, which is occurring at an estimated rate of about 7.3×10^10 kg per second.
-
The Following 11 Users Say Thank You to Atlas For This Post:
Agape (15th March 2015), Alekahn2 (15th March 2015), Bob (16th March 2015), Cidersomerset (15th March 2015), DeDukshyn (15th March 2015), Hod8 (15th March 2015), mab777 (15th March 2015), Octavusprime (16th March 2015), ponda (15th March 2015), seko (15th March 2015), Stephanie (15th March 2015)
-
15th March 2015 21:18
Link to Post #3