Explanation: A weekend trip for astrophotography in central Australia can result in gorgeous skyscapes. In this example recorded in March of 2006, the center of our Milky Way Galaxy rises over planet Earth's horizon and the large sandstone formation called Uluru, also known as Ayers Rock. After setting up two cameras to automatically image this celestial scene in a series of exposures, one through a wide-angle and the other through a telephoto lens, photographer Joseph Brimacombe briefly turned his back to set up other equipment. To his surprise, the ground around him suddenly lit up with the brilliant flash of a fireball meteor. To his delight, both cameras captured the bright meteor streak. Highlighted in the telephoto view (inset), the fireball trail shines through cloud banks, just left of Ayers Rock.

APOD: 2008 June 28 - Fireball at Ayers Rock

Florida's shark population is diverse and includes species that range in size from only a few feet to more than 40 feet in total length. Experts caution sea-goers to beware of sharks 6 feet or longer due to the damage they can cause in a single bite. Among the species that grow to this size and have been known to attack humans are bull sharks, tiger sharks and great white sharks. However, these are not the predominant shark species that a person is likely to come across in Florida waters. The following species are among the most common.

Common Sharks of Florida

Basic Surf Forecasting - Reading a Synoptic Chart

Brasurf - Surf Forecasting

Excellent series of articles about surf forecasting at magicseaweed

Surf Reports, Surf Forecasts and Surfing Photos

Ocean Science 101: How our surf is made
OK this will probably review for a lot of you, but I thought I would go back and cover some of the basics in surf forecasting. I have been posting forecasts, reports, maps, and other random nonsense for a while now and I started to realize that a lot of the stuff that I have been throwing at you assumes that you have an idea of how our surf is generated. It isn’t really that hard to find on the interweb, (I mean, come on, that is what Wikipedia was invented for people), but I decided to throw it up here too so that you didn’t have to hunt around for it.

Why it matters

I am sure that there are some of you out there that don’t really care about where the waves come from and are fine with just knowing if the surf is going to be good tomorrow. That is totally cool…I hope that I keep my forecasts simple enough that you can keep scoring…or at least save some gas money now and then.

Personally I think that you become a better surfer, and a better waterman, if you get in tune with the ocean, the weather, and the processes that create the conditions that we, as surfers, are looking for. You don’t need to be a forecaster or anything but I do think that knowing the general principles behind how waves are made will keep you a step ahead of other surfers, which is nice, particularly when that step could mean the difference between scoring empty surf and slogging it out with the rest of the crowd that is a day late and a dollar short.

Southern California Surf Forecast: Ocean Science 101: How our surf is made

Pretty good surf forecasting.

Wetsand.com - Surf Reports - Home Page

"It must be ice," said Phoenix Principal Investigator Peter Smith of the University of Arizona, Tucson. "These little clumps completely disappearing over the course of a few days, that is perfect evidence that it's ice. There had been some question whether the bright material was salt. Salt can't do that."

The chunks were left at the bottom of a trench informally called "Dodo-Goldilocks" when Phoenix's Robotic Arm enlarged that trench on June 15, during the 20th Martian day, or sol, since landing. Several were gone when Phoenix looked at the trench early today, on Sol 24. [University of Arizona Mars Phoenix Mission]

LAist: Water Ice Found on Mars

INTRODUCTION

Any time you picture a body of water larger than a puddle, one of the first things that comes to mind are the rolling waves, or the surf lapping at the shore. Well, at least that's what happens with me... But waves are much more than tranquil anomalies, they can be dangerous and destructive to any vessel in almost any body of water. Understanding how waves are made, how they normally behave, and how to predict their response to weather can make the difference between a smooth, comforting time on the water and a bumpy, frightening experience.

The first rule of waves, especially in the open ocean, is that there are no rules. Kind of a hypocritical statement considering the intent behind this article, but it is a hard, cold fact. There are simple physical factors that makeup the "normal" wave, but within the forces of nature, there a myriad of other factors that need be considered into the equation. Regardless, an understanding of what makes a "textbook" wave can be of considerable merit to the sailor. What we will examine here are the laboratory examples of wave creation. How, in a perfect world, waves would behave. In reality, alternating weather patterns, varying water depths, opposing currents, fetch obstruction and a multitude of other factors may change the way waves in a particular area react.

Anatomy of a Wave - by Jay Holben

Why is a groundswell called a "ground" swell? Isn't it just a strong windswell from farther away?
asked by Larry

Answer

Leading surfing meteorologist and Surfline forecaster Sean Collins responds:

Well, you're pretty close Larry, but it's slightly more complicated than just a simple naming convention.

Windswells are swells that are generated by local winds within a few hundred miles of the coast. As a result, the swell periods are short (four to 10 seconds between crests) and the waves tend to stack up on each other with very consistent sets. Also, a windswell's energy doesn't extend very deep -- maybe only 100 feet or so -- so it can only travel a few hundred miles before dissipating because most of the wave energy is concentrated closer to the ocean surface.

Groundswells are swells that are usually generated by winds much farther away. These swells are created by strong winds over long distances -- we refer to this distance as the "fetch" -- and over longer periods of time. As a result, more energy is transferred into the water during the generation of the waves, which create longer swell periods. Waves with longer swell periods can travel great distances without losing the swell energy like windswells do. Furthermore, swell energy in groundswells can also extend down to around 1,000 feet deep. This allows greater interaction with the ocean floor when the groundswells move into shallow water. For example, this process of refraction will allow groundswells to wrap into a spot -- up to 180 degrees or more -- while windswells wrap very little if at all.

What is a ground swell? | Surfline | Who the F&*K Knows

Some shark populations in the Mediterranean Sea have completely collapsed, according to a new study, with numbers of five species declining by more than 96 percent over the past two centuries.

“This loss of top predators could hold serious implications for the entire marine ecosystem, greatly affecting food webs throughout this region,” said the lead author of the study, Francesco Ferretti, a doctoral student in marine biology at Dalhousie University in Nova Scotia.

I have mixed feelings about sharks, but this not good.

Some Shark Populations Collapsing - NYTimes.com