Astronomy

Welcome to Duck Bay, Victoria crater, Mars

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Nearly three years after landing on Mars, the rover "Opportunity" has reached a region of the planet that may provide the best clues yet about the history of the red planet.

The golf cart-sized robot is now overlooking Victoria Crater, showing us rugged walls with layers of exposed rock and a floor blanketed with dunes. Take a look at this magnificent panorama, taken from 800 meters distance.

Both Mars robots got recently a software update comparable to a Y2K fix : both rovers are nearing 1000 days of operational status, and the original software only had 3 digits for the current day. Opportunity will the next weeks be exploring the Victoria crater, searching the crater rim to see if there's any way it can get down into the crater. For geologists, deeper usually means farther back in time. By going down deeper, in a place five times bigger than the last craters, we hope to see the history of Mars.

Plutons

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There has been a lot of debate recently about the demotion of Pluto as a planet. Pluto is a weird planet : it is the farthest one, has an eccentric orbit (where it becomes closer to the sun than Neptune at one point) and has a moon that is almost as large as itself. It's also discovered by Clyde Tombaugh, an American, a subtle and important fact, cause this whole discussion is mostly a political one.

The first proposition was to include Ceres (an asteroide between Mars and Jupiter) and Xena, recently discovered as the tenth planet, in the list as officially acknowledged planets. The problem with that resolution was that there are more objects in the solar system which would be classified as planets.

The second proposition was to remove Pluto as a planet, and call objects of its size as 'Plutons', or dwarf planets. However, the discussion is still open, and lots of scientist would like to see Pluto to reappear as planet.

Xena, the tenth planet, just got renamed as Eris, which is more according to the standard of giving planets the name of Roman and Greek gods. In Greek mythology, Eris is the goddess of warfare and strife. She stirs up jealousy and envy to cause fighting and anger among men. At the wedding of Peleus and Thetis, the parents of the Greek hero Achilles, all the gods with the exception of Eris were invited, and, enraged at her exclusion, she spitefully caused a quarrel among the goddesses that led to the Trojan war. In the astronomical world, Eris stirred up a great deal of trouble among the international astronomical community when the question of its proper designation led to a raucous meeting of the IAU in Prague. At the end of the conference, IAU members voted to demote Pluto and Eris to dwarf-planet status, leaving the solar system with only eight planets.

The satellite of Eris has received the offical name Dysnomia, who in Greek mythology is Eris' daughter and the demon spirit of lawlessness. As promised for the past year, the name Xena (and satellite Gabrielle) were simply placeholders while awaiting the IAU's decision on how an official name was to be proposed. As that process dragged on, however, many people got to know Xena and Gabrielle as the real names of these objects and are sad to see them change.

Solar foil

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I purchased recently some solar foil; it's the best way to observe the sun safely : ocular solar filter are just unsafe, because of the high temperatures it receives by all the concentrated sunlight in your telescope. Solar projection is rather awkward to take pictures.

Solar foil reduces the sunlight to 0.000 01 percent of its strength, which gives nice pictures like the inset here. Unfortunately the sun surface is quite boring the last days : not a single tiny sunspot in sight.

Huge storms converge on Jupiter

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The two biggest storms in the solar system are about to collide on Jupiter, in plain view of backyard telescopes. The Great Red Spot, and Oval B (aka Red Jr) are on a close encounter course around the 4th of July. There won't be a head-on collision, The Great Red Spot is not going to 'eat' Oval BA or anything like that. But the storms' outer bands will pass quite close to one another and no one knows exactly what will happen.

Storm #1 is the Great Red Spot, twice as wide as Earth itself, with winds blowing 350 mph. The behemoth has been spinning around Jupiter for hundreds of years. Storm #2 is Oval B, also known as "Red Jr.," a youngster of a storm only six years old. Compared to the Great Red Spot, Red Jr. is half-sized, able to swallow Earth merely once, but it blows just as hard as its older cousin.

Jupiter will be an interesting object to watch in the coming weeks. What will actually happen? We'll see, that's what telescopes are for.