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Artist’s conception of the New Horizons spacecraft flying past Pluto and Charon
More dramatic news from the far reaches of the solar system: NASA’s probe New Horizons has awakened from its nine year hibernation and is powering up to approach Pluto! Although it sounds like “New Horizons” is a boy band, NASA gave up on trying to launch every saccharine teenybopper act into the Kuiper belt (although that is a laudable goal): instead the probe is named after the fact that New Horizons is the first human spacecraft to explore the dwarf planet Pluto and its little moons Charon and Hydra. Launched in January of 2006, New Horizons set the record for the highest launch speed of a human-made object from Earth. The grand piano-sized spacecraft has spent the intervening years hurtling through the darkness of space–although it has periodically come to partial wakefulness to check in with mission control and to snap some dramatic flyby photos of famous locations along its trip (like this photo montage of Jupiter and Io). The craft also used Jupiter’s gravity well to increase its velocity.
Composite image of Jupiter and Io as photographed from New Horizons (NASA)
Since the time the probe was launched, astronomers have discovered two new miniature moons of Pluto: Kerberus and Styx. This means that New Horizons mission planners were forced to assess the possibility of a catastrophic collision with unseen debris or dust left over from these satellites. Computer models suggest that the likelihood of such an accident is remote, but, just in case, NASA has added two dramatic contingency plans for the mission. In one emergency plan, the probe’s satellite dish acts as a dust shield, in the other, the craft drops dangerously close to Pluto, where atmospheric drag has presumably cleared the surrounding space of particles. These worst case plans will almost certainly not be needed, although we will learn more as New Horizons gets closer to the dwarf planet.
After flying past Pluto next July, New Horizons will hurtle into the Kuiper belt where NASA hopes the probe will rendezvous with an icy Kuiper belt object so that we can learn more about these enigmatic leftovers from the creation of the solar system. The coming 7 months should be filled with excitement as we learn more about the Pluto system!
A Composite Image of M104–The Sombrero Galaxy–taken from the Hubble Space Teelscope in Summer of 2003 (click on the image for a full-sized version)
Today I am posting some pictures of what I think is the most beautiful deep space object. The Sombrero Galaxy (M104) is a nearby galaxy which is visible edge-on in the constellation of Virgo. Actually, calling it an object might be a bit misleading since M104 consists of more than 400 billion stars–not to mention numerous associated globular clusters, innumerable planets, immense clouds of gas & gas, and a supermassive black hole which lies in the center. The black hole in the center of M104 isn’t a mild mannered & quiescent black hole like the one in the center of the Milky Way either. Based on the speed of revolution of the stars near the middle of M104, astronomers calculate that the central black hole has a billion times the mass of the sun.
An Infrared false-color image of the Sombrero Galaxy
In cosmic terms, the Sombrero galaxy is nearby—which is to say it is merely 28-odd million light years away. The galaxy was discovered in the late eighteenth century by Pierre Méchain . Other prominent 18th century astronomers subsequently observed and studied M104, including Charles Messier (which is the reason the galaxy is included in the “Messier” catalog and has a M-designation) and the redoubtable William Herschel who noted a “dark-stratum” bounding the luminous central bulge. We now know that this ring around M104 is a toroid dust lane of vast proportions which halos the galaxy. Astronomers initially thought that the Sombrero Galaxy was an unbarred spiral galaxy, but thanks to observations from NASA’s Spitzer space telescope (an infrared scope orbiting Earth), the scientific community has revised their estimation of its size upward. It lies somewhere between a spiral galaxy and an elliptical galaxy. In other words, when you look at the Sombrero Galaxy, you are looking at something vast beyond human comprehension—a galaxy bigger than our own filled with who knows what things we will never know. And yet if you expand the Hubble photo at the top of this post, you will see that all of the little stars shining around M104 are other galaxies farther away.
Olé!
A Comparison of the relative sizes of the Fomalhaut system and the solar system (image created by NASA and ESA)
Fomalhaut is a star with twice the mass of the sun located approximately 25 light-years from Earth in the constellation Piscis Austrinus. It is a bright young star 100 to 300 million years old (out of a projected lifespan of 1 billion years). Coinicientally the name Fomalhaut is Arabic and means “mouth of the Southern fish.” Fomalhaut has at least one planet—Fomalhaut b, which is believed to be approximately the same size as Jupiter (but could be anywhere from the size of Neptune to 3 times as large as Jupiter). Just as Saturn is surrounded by a ring of debris, the entire star system of Fomalhaut is surrounded by a giant toroidal circumstellar disk. This torus is vastly greater in diameter than our entire solar system (including the Oort Belt) and is made up of somewhere between 260 billion and 83 trillion comets which are constantly colliding and annihilating each other! The Herschel Space Observatory recently captured an infrared image of this immense comet storm.
An infrared image of the Fomalhaut system--and its huge cloud of disintegrating comets) captured by the Herschel Space Observatory (credit: ESA)
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