This January, the American Astronomical Society held its big annual meeting completely online. The Covid-19 pandemic ruled out the society’s planned gathering in Scottsdale, AZ but the AAS pivoted by opening-up digital access to thousands of astronomers across the United States and around the world. More than 3,000 registrants were listed in the online portal, thus demonstrating that the vital communication of astronomical research, education, and public outreach could carry on in this alternative format.
If the Big Bang theory is correct, how fast is the universe expanding? Astronomers are facing a troubling disconnect between different methods used to measure the expansion rate, known as the Hubble constant. The two methods are giving similar but slightly different rates. Either one method is providing inaccurate results, or there is some kind of unknown physics operating in the universe.
A photo/video account of comet NEOWISE by Gloucester Area Astronomy Club astrophotographer Jeremy Parker, and a review of some of the more recent Great Comets.
I just finished a little project to put some of my recent images to music in a slideshow video, most of which I showed at our recent GAAC astrophotography virtual meeting. This is my first attempt at such a video, but I think I will make them periodically, moving forward. I figured I would share it here, as you might find it entertaining or relaxing. Enjoy!
Galactic ecosystems encompass the varied complexes of inter-relating stellar, nebular, and other matter that are actively forming new stars. These include molecular clouds, cloud cores, protostellar and protoplanetary systems, HII regions and starbursts.
It is not hyperbole to state that galactic ecosystems have spawned pretty much everything that we hold dear – including ourselves. These nebular nurseries have incubated all the stars, planetary systems, and many of the complex molecules known to humanity.
More than fifty years ago, Apollo 15 photographed something unusual on the far side of the Moon. In a panoramic photograph taken from lunar orbit, two bright, sharply defined objects stood out from the otherwise subdued landscape on the floor of a crater called Paracelsus C.
Today we can take a much closer look.
The formula for collisional excitation of the atoms responsible for auroral emission can explain why green auroras from excited oxygen atoms can occur at relatively low altitudes, but red auroras from these same atoms are constrained to higher altitudes of lower density. The same formula also suggests much lower electron velocities (~100 km/s) than are required to excite the oxygen atoms to the required metastable levels for subsequent emission (~1000 km/s).
A photo/video account of comet NEOWISE by Gloucester Area Astronomy Club astrophotographer Jeremy Parker, and a review of some of the more recent Great Comets.
