Tag Archives: Space

Closest Star System Found in a Century

WISE J104915.57-531906 is at the center of the larger image, which was taken by the NASA's Wide-field Infrared Survey Explorer (WISE). Image credit: NASA/JPL/Gemini Observatory/AURA/NSF

NASA’s Wide-field Infrared Survey Explorer (WISE) has discovered a pair of stars that has taken over the title for the third-closest star system to the sun. The duo is the closest star system discovered since 1916.

Both stars in the new binary system are “brown dwarfs,” which are stars that are too small in mass to ever become hot enough to ignite hydrogen fusion. As a result, they are very cool and dim, resembling a giant planet like Jupiter more than a bright star like the sun.

“The distance to this brown dwarf pair is 6.5 light-years — so close that Earth’s television transmissions from 2006 are now arriving there,” said Kevin Luhman, an associate professor of astronomy and astrophysics at Penn State University, University Park, Pa., and a researcher in Penn State’s Center for Exoplanets and Habitable Worlds.


“It will be an excellent hunting ground for planets because the system is very close to Earth, which makes it a lot easier to see any planets orbiting either of the brown dwarfs.”

The results will be published in the Astrophysical Journal Letters.

The star system is named “WISE J104915.57-531906″ because it was discovered in an infrared map of the entire sky obtained by WISE. It is only slightly farther away than the second-closest star, Barnard’s star, which was discovered 6 light-years from the sun in 1916. The closest star system consists of: Alpha Centauri, found to be a neighbor of the sun in 1839 at 4.4 light-years away, and the fainter Proxima Centauri, discovered in 1917 at 4.2 light-years.

Edward (Ned) Wright, the principal investigator for the WISE satellite at UCLA, said, “One major goal when proposing WISE was to find the closest stars to the sun. WISE J1049-5319 is by far the closest star found to date using the WISE data, and the close-up views of this binary system we can get with big telescopes like Gemini and the future James Webb Space Telescope will tell us a lot about the low-mass stars known as brown dwarfs.”

The Gemini South telescope in Chile was also used in this study for follow-up observations.

WISE completed its all-sky survey in 2011, after surveying the entire sky twice at infrared wavelengths. The maps have been released to the public, but an ongoing project called “AllWISE” will combine data from both sky scans. AllWISE will provide a systematic search across the sky for the nearby moving stars such as WISE J104915.57-531906, and also uncover fainter objects from the distant universe. Those data will be publicly available in late 2013.


Aegis Ballistic Missile Defense System Scores Another Hit

This photo is pretty impressive. The story behind it is even more impressive. It shows the test of the U.S. Navy’s Aegis Ballistic Missile Defense System, the sea-based component of the Missile Defense Agency’s Ballistic Missile Defense System. So what happened during this joint MDA and Navy test?


  • At 11:10 p.m. HST last Tuesday, a medium-range ballistic missile target was launched from the Pacific Missile Range Facility, on Kauai, Hawaii.
  • The target flew northwest towards a broad ocean area of the Pacific Ocean.
  • The in-orbit Space Tracking and Surveillance System-Demonstrators detected and tracked the target.

Space Tracking and Surveillance System-Demonstrator (Source: Northrop Grumman)

Space Tracking and Surveillance System-Demonstrator (Source: Northrop Grumman)

  • It forwarded track data to USS Lake Erie (CG 70), which is equipped with the second-generation Aegis BMD weapon system, to engage the target with Launch on Remote doctrine.
  • The ship developed a fire control solution from the STSS-D track and launched the SM-3 Block IA guided missile approximately five minutes after the target launched.
  • The SM-3 intercepted the target and vaporized it following a direct-hit minutes after its launch.

This marked the first live-fire intercept of a medium-range ballistic missile using space-based sensors. It was the 24th successful intercept in 30 flight test attempts for the Aegis BMD program since flight testing began in 2002.