March 22, 2019

15.10.11: The Strange New World of Vesta.

Vesta’s south pole region as seen from Dawn’s framing camera. (Credit: NASA/JPL).

NASA’s Dawn spacecraft remains the mission that perhaps you’re not following, but should be… since entering orbit around the main belt asteroid 4 Vesta, the plucky ion-propelled spacecraft is returning some fairly mind-blowing images.  The asteroid/proto-planet/insert-current-favorite-definition is becoming a brave new world before our very eyes, the first dwarf planet we’ve orbited and reconnoitered in detail. What are those ridges? What caused intriguing features such as the overlapping crater doublet dubbed “the Snowman?” [Read more...]

Review: How I Killed Pluto & Why it Had it Coming by Mike Brown.

Target: Pluto?

Caltech Astronomer Mike Brown is on the cutting edge of modern day “faint fuzzy” hunting at the fringe of the solar system and has found himself at the epicenter of several scientific battles over the past decade. In How I Killed Pluto & Why it Had it Coming, Dr. Brown takes us behind the scenes of his discoveries and, after a brief history of solar system exploration, takes us on a deeply personal tale of modern discovery and a fascinating look at how modern astronomy in the Internet era gets done. Intertwined with the tale of successive discoveries in the outer solar system is an intimate look at Mike’s personal world, his family, and how a scientist and his family operates… just think, how many of us personally know a true scientist, in our families or on the block? [Read more...]

03.05.11: The Mysteries of Vesta.

A projected model of Vesta. (Credit: NASA/JPL/CALTech/UCLA/PSI).

In a string of recent firsts, scientists are about to get a good look at an enigmatic solar system body for the first time this summer. Launched in 2007, NASA’s Dawn spacecraft is due to orbit the asteroid Vesta in August of this year, giving us the first non-blurry close up images of the 530 kilometer diameter world. [Read more...]

04.02.10: Pluto Re-imaged.

The most controversial planet (or do you say dwarf planet, or plutoid?) got a new look today. In a press conference, NASA researchers revealed the new “face” of Pluto; a series of images spanning 270 degrees of rotation. To complete these, astronomers scoured 384 images for 4 years using no less than 20 computers. These images were acquired from the Hubble Space Telescope’s Advanced Cameras for Surveys, and span a period from 2002-03. Even under the most favorable conditions, Pluto is a tough target; at around 0.1” arc seconds in size, Pluto only covers only a few pixels even in the best cameras and telescopes. The images are in true color, and present a tan-ish to grey world that is perhaps Mars-like in appearance. This is suggestive of a broad diversity of plutonian topography, and comparisons with the 1994 images show correlations with bright surface features, but also changes that hint at seasonal variations. Specifically, Pluto appears significantly redder and shows a magnitude variation of 0.2 magnitudes, which is surprising over a short 8 year span…Pluto takes 248 years to complete one orbit. Charon, Pluto’s large moon, was a good “color test” as it stayed the same throughout both imaging cycles, lending credence to the idea that the changes throughout were real and not an artifact.

Spectroscopic analysis reveals that Pluto is a dynamic world, covered by frozen methane and fluro-hydrocarbons. In fact, it’s suggested that the world may be a twin to Triton, Neptune’s largest moon. “Certainly, the Kuiper Belt is an amazing place,” such researcher Mike Brown, who laughed at the idea that perhaps Pluto was getting redder in anger at him due to its recent demotion. Hubble’s newly installed WFC3 camera will begin imaging Pluto over a five month period starting April 2010, in anticipation of the New Horizons flyby in 2015. And all this on today, Clyde Tombaugh’s 104th birthday! Expect those astronomy text books to be changing soon…

AstroEvent of the Week: October 27th- November 2nd; A Halloween Asteroid.

This Halloween brings a chance to spot one of the brightest known asteroids. 4 Vesta is currently placed in the constellation Cetus, the Whale and will be in opposition on October 29th this year, and thus be visible in moonless skies nearly all night.

[Read more...]