Amateur astronomers fond of visual observation of faint galaxies and other fuzzy treasures of the night sky are always in search of the best observative site, where to drag their large Dobsonian telescopes.

Unfortunately, their road is always uphill - also in a metaphorical sense: light pollution is growing everywhere at a disturbing rate, and it has already erased all but the brightest stars from our urban and suburban skies.

Many of our kids grow without having seen the Milky Way, and the few who are drawn to astronomy are surprised to realize, from the tales of older dogs like me, that it did not use to be that way.
Moon Or Mars?

Moon Or Mars?

Aug 08 2009 | 8 comment(s)

One of the current questions for the future of space exploration is whether to return to the moon, or just head to Mars.

Should we return somewhere we’ve been before? Or just strike out toward someplace totally new? Is there any benefit to going back to the moon? Can we make it to Mars without building up our endurance and scientific knowledge on the moon first?

There are intelligent, well-connected, even famous, proponents on both sides.
Although he might not have been the absolute first to propose it, Galileo is widely credited with proposing the concept in 1638 that all bodies fall with equal acceleration through a vacuum, and mythologically with actually testing it at the Leaning Tower of Pisa.  This concept was a necessary precursor to Newton's law of universal gravitation (ask me sometime why the inverse square rule is SO COOL) and Einstein's general theory of relativity.

Over 300 years later, David Scott, commander of Apollo 15, decided to test Galileo's theory.  On the Moon.
Hitler's gift to astronomy? What?

Believe it or not, Hitler wanted to give Mussolini and Rome a planetarium*. Rome was among the first in the world to build a planetarium. Italy (and Mussolini) had already taken a planetarium as part of the 'compensation' for the damage Germany did to Italy in WW1 and opened the first Roman planetarium already in 1928.

It is the most peculiar story, so much so that I feel compelled to tell, however little, what I know about this hidden treasure of planetarium history...
HD 87643, a member of the exotic class of B[e] stars, is in a very rich field of stars towards the Carina (the Keel) arm of the Milky Way. It recently became part of a set of observations that provide astronomers with the best ever picture of a B[e] star.

B[e] stars are stars of spectral type B, with emission lines in their spectra, hence the "e". They are surrounded by a large amount of dust.
Betelgeuse, the second brightest star in the constellation of Orion (the Hunter), is a red supergiant, one of the biggest stars known, and almost 1,000 times larger than our Sun.

To put that in perspective, if Betelgeuse were at the center of our Solar System it would extend out almost to the orbit of Jupiter, engulfing Mercury, Venus, Earth, Mars and the main asteroid belt.

Electromagnetic radiation (light, radio waves, X-rays, and microwaves) contains a varying electric field. When we talk about Polarization of this field, we refer to its direction. A new satellite named the Gravity and Extreme Magnetism Small Explorer (GEMS),  will be the first to systematically measure the polarization of cosmic X-ray sources. It is a new astrophysics mission led by NASA's Goddard Space Flight Center in Greenbelt, Md.

A new study in Nature offers an explanation for the origin of dwarf spheroidal galaxies, one of the current puzzles in our understanding of galaxy formation.

Dwarf spheroidal galaxies are small and very faint, containing few stars relative to their total mass. They appear to be made mostly of dark matter - a mysterious substance detectable only by its gravitational influence, which outweighs normal matter by a factor of five to one in the universe as a whole.

Enjoy star gazing? Lucky enough to be in the northern hemisphere August 11th and 12th?
Citizen scientists working through an online project called Galaxy Zoo have discovered a group of rare galaxies called the "Green Peas" which could lend unique insights into how galaxies form stars in the early universe.

Galaxy Zoo users volunteer their spare time to help classify galaxies in an online image bank.  When they came across a number of objects that stuck out because of their small size and bright green color, they dubbed them the Green Peas. Employing the help of the volunteers to further analyze these strange new objects, the astronomers discovered that the Green Peas are small, compact galaxies forming stars at an incredibly high rate.