This sky map shows the location of the star HD 219134 (circle), host to the nearest confirmed rocky planet found to date outside of our solar system. The star lies just off the "W" shape of the constellation Cassiopeia and can be seen with the naked eye in dark skies. It actually has multiple planets, none of which are habitable.

Like early explorers mapping the continents of our globe, astronomers are busy charting the spiral structure of our galaxy, the Milky Way. Using infrared images from NASA's Spitzer Space Telescope, scientists have discovered that the Milky Way's elegant spiral structure is dominated by just two arms wrapping off the ends of a central bar of stars. Previously, our galaxy was thought to possess four major arms. This artist's concept illustrates the new view of the Milky Way, along with other findings presented at the 212th American Astronomical Society meeting in St. Louis, Mo. The galaxy's two major arms (Scutum-Centaurus and Perseus) can be seen attached to the ends of a thick central bar, while the two now-demoted minor arms (Norma and Sagittarius) are less distinct and located between the major arms. The major arms consist of the highest densities of both young and old stars; the minor arms are primarily filled with gas and pockets of star-forming activity. The artist's concept also includes a new spiral arm, called the "Far-3 kiloparsec arm," discovered via a radio-telescope survey of gas in the Milky Way. This arm is shorter than the two major arms and lies along the bar of the galaxy. Our sun lies near a small, partial arm called the Orion Arm, or Orion Spur, located between the Sagittarius and Perseus arms.

Like early explorers mapping the continents of our globe, astronomers are busy charting the spiral structure of our galaxy, the Milky Way. Using infrared images from NASA's Spitzer Space Telescope, scientists have discovered that the Milky Way's elegant spiral structure is dominated by just two arms wrapping off the ends of a central bar of stars. Previously, our galaxy was thought to possess four major arms. This annotated artist's concept illustrates the new view of the Milky Way, along with other findings presented at the 212th American Astronomical Society meeting in St. Louis, Mo. The galaxy's two major arms (Scutum-Centaurus and Perseus) can be seen attached to the ends of a thick central bar, while the two now-demoted minor arms (Norma and Sagittarius) are less distinct and located between the major arms. The major arms consist of the highest densities of both young and old stars; the minor arms are primarily filled with gas and pockets of star-forming activity. The artist's concept also includes a new spiral arm, called the "Far-3 kiloparsec arm," discovered via a radio-telescope survey of gas in the Milky Way. This arm is shorter than the two major arms and lies along the bar of the galaxy. Our sun lies near a small, partial arm called the Orion Arm, or Orion Spur, located between the Sagittarius and Perseus arms.

Johannes Kepler was a German Astronomer best known for the laws of planetary motion.Kepler documented the explosion of a supernova in 1604, which was the last such event observed in our Milky Way galaxy and would later be known as "Kepler's supernova."Kepler wrote a book on the supernova of 1604 called De Stella Nova (Prague, 1606). This illustration from the book locates Kepler's supernova in the foot of the Ophiuchus constellation. This first edition copy belongs to the California Institute of Technology Archives and is one of 35 copies still in inexistence.

Johannes Kepler was a German Astronomer best known for the laws of planetary motion.Kepler documented the explosion of a supernova in 1604, which was the last such event observed in our Milky Way galaxy and would later be known as "Kepler's supernova."Kepler wrote a book on the supernova of 1604 called De Stella Nova (Prague, 1606). An illustration in the book locates Kepler's supernova in the foot of the Ophiuchus constellation. This first edition copy belongs to the California Institute of Technology Archives and is one of 35 copies still in inexistence.

Johannes Kepler was a German Astronomer best known for the laws of planetary motion.Kepler documented the explosion of a supernova in 1604, which was the last such event observed in our Milky Way galaxy and would later be known as "Kepler's supernova."Kepler wrote a book on the supernova of 1604 called De Stella Nova (Prague, 1606). An illustration in the book locates Kepler's supernova in the foot of the Ophiuchus constellation. This first edition copy belongs to the California Institute of Technology Archives and is one of 35 copies still in inexistence.