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Magnetar

Hvis en magnetar (en slags SGR, Soft gamma repeater eller AXP, Anomalous X-ray Pulsar) findes, formodes den at v�re er en speciel type af neutronstjerne som har et st�rkt magnetfelt. Teorien omkring disse objekter blev formuleret af Robert Duncan og Christopher Thompson.

Det formodes at hver tiende supernova eksplosion resulterer i en magnetar i stedet for de mere almindelige neutronstjerner eller pulsarer.

Universet udg�res af elementarpartikler og vakuum. Partiklerne er fordelt uj�vnt og partiklerne og partikelklynger ben�vnes forskelligt afh�ngig af t�thed og m�ngde; klyngerne sp�nder lige fra subatomare partikler til sorte huller.

En m�ngde af partikelklynger i vakuum er:

Gas | Atmosf�re | Solvind | Kosmisk str�ling | Asteroideb�lte | Stjernehob, Stjernet�ge | Solsystem | Galaksehob

Galakse relaterede artikler:

Aktiv galakse (Seyfert, Kvasar, Blazar) | M�lkevejen

Stjernerelaterede artikler incl. typer og stadier:

Astronomi | Brun dv�rg | Hvid dv�rg | Stjerne | R�d k�mpe | Neutronstjerne (pulsar, magnetar) | Kvarkstjerne | Sort hul

Stjernebegivenheder:

Supernova | Hypernova

Mindre himmellegemer:

Planet | M�ne | Komet | Meteoroide (meteor, meteorit, ildkugle) | Sm�planet (asteroide, planetoide)

Rumfart, rumrejse:

Rumelevator | Rumfart�j (rumraket, rumf�rge, rumskib) | Rumsonde | Rumstation | Astronaut | Kosmonaut

Andre emner:

Himmel | Himmellegeme | Satellit (Drabant) | Planetbane | Kosmologi | Big Bang | Big Crunch | Big Rip | Ormehul

Eksterne adresser

• NASA: "Magnetar" discovery solves 19-year-old mystery Citat: "...suggested a magnetic field strength of about 800 trillion Gauss...").
• Robert C. Duncan, University of Texas at Austin: 'Magnetars', Soft Gamma Repeaters & Very Strong Magnetic Fields
• NASA Astrophysics Data System (ADS): Duncan & Thompson, Ap.J. 392, L9) 1992
• NASA ADS, 1999: Discovery of a Magnetar Associated with the Soft Gamma Repeater SGR 1900+14
• Physics Web: January 2003: Strongest magnet in the cosmos Citat: "...This discovery represents a new frontier in neutron-star astrophysics. Since magnetars slow down rapidly, only a handful of them will be active and observable at any one time..."
• 2004-01-09, ScienceDaily: Magnetars, The Most Magnetic Stars Known, More Common Than Previously Thought Citat: "...Magnetars represent a new way for a star to shine, which makes this a fascinating field..."