Many stars end their existence by going out in a huge explosion known as a supernova. However, only a few of these stellar explosions have been caught in the act. When they are, spotting them successfully has been down to pure luck—until now. On 11 December 2015 astronomers not only imaged a supernova in action, but saw it when and where they had predicted it would be.
This week NASA is celebrating a quarter century of discoveries from one of the most revolutionary scientific instruments of all time, the Hubble Space Telescope. Launched into orbit aboard the Space Shuttle Discovery on April 25, 1990, the Hubble changed our understanding of the age of the universe, the evolution of galaxies and the expansion of space itself. Along the way it has had the equivalent of knee and hip replacement surgery: Five times, astronauts on the space shuttle paid a visit to swap out old batteries and install new instruments. Hubble’s fate, however, is uncertain. The Hubble was designed to be serviced by the space shuttle, but the space shuttle fleet was retired in 2011, and the Hubble hasn’t had a repair job since 2009. At some point, under the laws of entropy that dominate the cosmos, the Hubble will begin to deteriorate.
NASA’s Dawn spacecraft has traveled roughly 3 billion miles at this point and it’s finally set its sights on the dwarf planet Ceres. Images of Ceres were released back in December, but those images were just for calibration. Dawn’s recently captured pictures are about 27 pixels across, about three times better than what it took last month.
Orion, the hunter, is one of the most popular constellations in the night sky; so you may have already seen him this winter or in late fall. Throughout the year, no matter the season, when I am in schools with our Discovery Dome portable planetarium someone often asks me to point out Orion. The mighty hunter is also one of the largest and easiest constellations to find. Most people find it by locating the three stars that make up Orion’s “belt” which is an asterism or recognizable group of stars that are part of a constellation. The names of the three stars that make up Orion’s belt are Alnitak, Alnilam and Minatka. One of the brightest stars in the sky is on Orion’s right shoulder. It’s called Betelgeuse.
Orion’s belt is the only group of three stars that are spaced so evenly making them very easy to recognize. Once you have found the belt, the hunter easily pops into view especially when it is right overhead during the cold evenings of winter.
Besides being easy to spot, the constellation Orion is also where you will find one of the most beautiful objects in the night sky, the Orion Nebula. Count down to the third bright object in Orion’s sword and you will find not a star but the Orion Nebula. With binoculars focused on this object, you will find many stars rather than one.
So the next time you look for Orion in the night sky be sure to also take a look at the third object in his sword for the giant cloud of gas and dust that makes up this birthplace or stars and solar systems.
(credit: Adam Block) This new image was taken by astrophotographer Adam Block on October 8 using an SBIG STX-16803 camera with a hefty 36.8-by-36.8 millimeter CCD sensor that provides a 16.8 megapixel image, attached to the University of Arizona’s 32-inch Schulman Telescope.
ISON’s green glow may be due to the presence of carbon molecules and seems to be intact.
NASA, ESA and the Hubble Heritage Team (STScI/AURA) / October 9, 2013)
A new image of the sunward plunging Comet ISON suggests that the comet is intact despite some predictions that the fragile icy nucleus might disintegrate as the Sun warms it. The comet will pass closest to the Sun on November 28.
In this NASA Hubble Space Telescope image taken on October 9, the comet’s solid nucleus is unresolved because it is so small. If the nucleus broke apart then Hubble would have likely seen evidence for multiple fragments.
Moreover, the coma or head surrounding the comet’s nucleus is symmetric and smooth. This would probably not be the case if clusters of smaller fragments were flying along. What’s more, a polar jet of dust first seen in Hubble images taken in April is no longer visible and may have turned off.
Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)
As of Sept. 4th, Hubble astronomers have discovered an interesting surprise as they viewed over 100 planetary nebulae. They noticed that the butterfly shaped nebulae that form near the bulge of the Milky Way tend to be aligned with the plane of our galaxy. This is a surprising find seeing as how many of these nebulae have varying degrees of history and properties.
Planetary nebulae are the expanding jet-like streams that surround dying stars. It’s caused when a star blows out its outer layer into space long after the hydrogen has been used up. Astronomers have been finding these recently and it’s puzzling why so many of them appear to be aligned in the same direction since they have different characteristics and placements in our galaxy. It’s like bowling pins on a bowling alley.
It’s currently thought that the huge bulge that rotates around the galactic center has a large role in the outcome of how these planetary nebulae expel their outer layer. The magnetic fields of this rotating bulge may have a larger role in our galaxy than we previously thought. This is the larger part of the puzzle. The star system’s orientation before it turned into a red giant and if the star is part of a binary pair are also contributing factors to the direction the gaseous cloud erupts from the star.
Hubble astronomers are finding that planetary nebulae don’t align as much the further they get away from the galactic center. This suggests that the galactic bulge had a stronger magnetic influence as the galaxy formed, much like a compass has on its needle.
The interesting aspect of this is that if the magnetic influence of the central rotating bulge has this type of affect on stars than it also has a surprising authority for the rest of the galaxy as well.