Imaginea Astronomica a Zilei

Descopera cosmosul! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

May 3, 1999
See Explanation.  Clicking on the picture will download 
 the highest resolution version available.

Loop I in the Northern Sky
Credit: ROSAT, MPI, ESA, NASA

Explicatie: (Edit) One of the largest coherent structures on the sky is known simply as Loop I and can best be seen in radio and X-ray maps. Spanning over 100 degrees, part of Loop I appears so prominent in northern sky maps that it is known as the North Polar Spur (NPS). Loop I, shown above in X-ray light, is a thin bubble of gas about 700 light-years across with a center located only about 400 light-years away. Surprisingly, the cause of this immense structure is still debated, but is possibly related to expanding gas from a million-year old supernova. Loop I gas is impacting the nearby Aquila Rift molecular cloud, and may create relatively dense fragments of the local interstellar medium. Were our Sun to pass through one of these fragments in the next few million years, it might affect Earth's climate.

Imaginea de maine: Magnetic Mars


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Autori & editori: Robert Nemiroff (MTU) & Jerry Bonnell (USRA)
Reprezentanti tehnici NASA: Jay Norris. Specific rights apply.
Un serviciu al: LHEA at NASA/ GSFC
& Michigan Tech. U.