The European Space Agency's Envisat satellite snapped this picture of a marine phytoplankton bloom forming off the coast of Spain, in the Bay of Biscay. Blooms like this occur frequently in the bay this time of year, since the water is cold, but very nutrient rich. As the water warms to a certain level, the plankton's growth explodes. It's important to monitor these blooms, as phytoplankton forms the base of the marine food chain.

Our star goes through an 11-year cycle of solar activity. At the recent height of the cycle, the Sun blasted off some of the most powerful flares and coronal mass ejections ever seen. And during the minimum, due in 2006, it's supposed to be calm, right? Well, not exactly. Even during the lowest point of solar activity, the Sun still blasts off a few of the most powerful X-class flares. Unprotected astronauts caught in the radiation would probably get pretty sick.

The amount of sunlight reaching the Earth's surface has been on the rise for the past decade on average, potentially accelerating the effects of global warming. Scientists had been measuring a decrease in sunlight from the 1960s to the 1990s, because of rising pollution was actually blocking sunlight. With better pollution controls in place, the planet's surface has brightened by about 4% in the last 10 years.

Prolonged exposure to microgravity causes astronauts to lose bone and muscle, so they have to exercise for hours a day to stay healthy. NASA is working on a new strategy that could involve just laying down and going for a spin - in a short-radius centrifuge. 32 test subjects will spend 21 days in bed rest, simulating the effects of microgravity. Some will spend an hour a day in a centrifuge that simulates 2.5 times the Earth's gravity. It's hoped that this treatment can reverse the loss of bone and muscle mass.

Skywatchers are in for a treat tonight as the eta Aquarid meteors will be putting on a show. Observers in the southern hemisphere should be able to see 15-60 meteors an hour depending on the darkness of the skies. Those in the northern hemisphere won't be so lucky, seeing only about 10 meteors an hour. Look to the constellation of Aquarius, towards the East in the early morning of May 6, and you should see a more than a few meteors. Be patient, dress warmly, and bring a friend or two..

The European Space Agency's Envisat satellite is building up the highest resolution map ever created of the entire Earth. Once complete, it will provide coverage of the every spot on Earth with three times the resolution of any previous survey. The final image set at a resolution of 300 metres will use up 20 terabytes of memory, and provide a resource for scientists, developers, and planners.

Geologists have built up a suite of tools and techniques that let them peer back in time to watch the formative stages of the Earth and how it's changed over time - by looking inside rocks. By analyzing trapped water and air in rocks, geologists are studying how our atmosphere changed 3.9 billion years ago, when the crust of the planet was just forming, and there wasn't any oxygen in the air.

Astronomers aren't stuck looking at plain old light any more. There's a whole electromagnetic spectrum out there, ready to be explored, from 21cm hydrogen radio-waves through microwave, infrared, ultraviolet, x-rays, to gamma rays and beyond, astronomers have instruments for all seasons and all wavelengths. High-energy gamma rays are blocked by the Earth's atmosphere - which is good for our health - but astronomers can still see them thanks to a process called Cherenkov radiation telescopy.

The theory of panspermia proposes that life really gets around, jumping fron planet to planet - or even from star to star. Life might be everywhere! Assuming this is true, how do single-celled bacteria make the journey through the vacuum of space? Easy, they use chunks of rock as space ships, in a process called lithopanspermia. And now, researchers from Princeton and the University of Michigan think that life carrying rocks might have been right there at the beginning of our solar system, keeping their tiny astronauts safe and sound, frozen in statis until the planets formed and the right conditions let them thaw out, stretch their proteins, and begin a process leading from microbe to mankind.

The European Space Agency's Rosetta spacecraft took this image of our home planet during its recent gravity assisting flyby. The spacecraft swept past the Earth on March 4/5 to get a speed boost on its way to Comet 67P/Churyumov-Gerasimenko. It studied the Earth and Moon using several instruments while it was in the neighbourhood and now the ESA has processed the images it sent back.

The next mission to make the journey to the Red Planet, the Mars Reconnaissance Orbiter, has arrived at Kennedy Space Center in Florida. Engineers will assemble various components, and test everything to ensure it's ready for launch. If all goes well, the MRO will lift off in August atop a Lockheed Martin Atlas V rocket, and then make the journey to Mars. MRO will study both the surface and underground of Mars in tremendous detail, and survey potential future landing sites.

NASA has decided to push back the launch of the space shuttle Discovery to July to give engineers more time to deal with some potential safety concerns with the return to flight. Managers are concerned about ice building up on the shuttle external tank, which could fall off and damage the orbiter during take off. The shuttle will be rolled back to the assembly building to make additional improvements. NASA is currently targeting a launch window of July 13 to 31.

Greetings, fellow SkyWatchers.This week's early dark skies will promote plenty of deep space action as we view the M51, M94, M53, and M64. Mid-week will provide some excitement as the reliable children of Comet Halley streak across our atmosphere during the peak of the Eta Aquarid meteor shower. In two months, Deep Impact will have reached Comet Tempel 1 - but why wait until then to view it? You can see it now! The call goes out to observers to help in scientific study and the week ends with a special treat. So grab your binoculars and telescopes and head out under dark skies...

Because here's what's up!

Alan Shepard flew first in the United States' space program and second overall in the space race. A brief 15 minute suborbital flight pitched him a few hundred kilometres east of his launch site. Later, as commander of Apollo 14, he walked on the moon's surface. But with 74 years of living, there was much more to his life which Neal Thompson openly and warmly presents in his marvellous book, Light This Candle, The Life and Times of Alan Shepard.

Astronomers working with the European Southern Observatory have confirmed the first direct photograph of a planet orbiting another star. The team originally announced their discovery in September 2004, but they confirmed their findings this year using the powerful new NACO instrument on ESO's Very Large Telescope in northern Chile. The planet is approximately five times the size of Jupiter, and orbits its brown dwarf star at about the distance that Neptune travels around the Sun.

Now that it's completed flybys past several of Saturn's moons, Cassini will spend the next five months analyzing the planet's great system of rings. It'll view the rings from a position inclined 24-degrees, and orbit the planet 7 times, from now until September. This perspective will allow Cassini to analyze the rings in various wavelengths of light, from infrared to visible to ultraviolet. Cassini will also be in the perfect position to watch several occultations, where the rings pass in front of stars, and help scientists precisely measure their thickness and opacity.

Gravitational lensing happens when the gravity of a relatively close galaxy acts as a telescope lens to focus the light from a more distant galaxy. It allows astronomers to see distant objects they could never have a hope of observing with current instruments, essentially looking back to moments after the Big Bang (cosmically speaking). The galaxies are never perfectly lined up, though, and the "natural telescope" is a bit blurry. But now astronomer Remi Cabanac has found one of the most complete lenses ever discovered: a near perfect Einstein Ring, magnifying a distant galaxy with incredible clarity.

Before the first human steps foot on the Moon again, robots will have already done the ground work, searching out sources of water ice that could be used for fuel, air, and growing plants. The first will be the Lunar Reconnaissance Orbiter, scheduled for launch in 2008. It will carry 6 different instruments, and map out the surface of the Moon in high detail. Approximately one new mission will launch each year after that, until humans arrive on the Moon, no later than 2020.

Mission controllers at the European Space Agency are now planning to deploy the Mars Advanced Radar for Subsurface and Ionosphere Sounding instrument (MARSIS) on Mars Express in the first half of May. They delayed deploying the two 20-metre (65 foot) booms (and another, smaller boom) because simulations predicted that they could swing back and actually hit the spacecraft. They will put the spacecraft in a mode that will allow it to tumble freely while the deployment is performed to minimize risk to Mars Express.

This image, taken by the European Space Agency's Mars Express spacecraft, shows the Tithonium Chasma region of the Valles Marineris canyon on Mars. It ranges from 10 to 110 km (6 to 68 miles) in width, and has a maximum depth of 4 km (2.5 miles). The edges of the canyon have gone through significant erosion, and it's possible to see several landslides. Since Valles Marineris cuts so deep into Mars' surface, it gives geologists a unique view back in time through Mars' geologic history.