Sometimes, distractions can be useful in themselves. That’s the message this week from the Planck space telescope, which has a mighty big mission: to take baby pictures of the universe. While it hasn’t yet accomplished that task, the preliminary disturbances that Planck scientists are now dealing with are yielding cosmic insights of their own.
Orbiting the Sun roughly 1.5 million kilometres from Earth, the Planck space-based telescope is scanning the sky for ultra-cold objects. Its instruments are chilled to just a tenth of a degree above absolute zero and are designed to pick up the faint microwave afterglow from the Big Bang, which scientists hope can tell them about the earliest moments of the Universe. [Nature News]
Planck was launched in spring of 2009 by the European Space Agency, and it’s still gathering data to complete its chart of this cosmic microwave background (CMB); researchers hope the map will shed light on the young universe’s brief “inflationary” period when it expanded extremely rapidly. At the moment, however, Planck is busy detecting other sources of microwaves so that it can subtract this “foreground” radiation from its map of the background.
So what are some of these sources?
OK, Mars wins this contest for bragging rights. The photo above shows the Melas Chasma on Mars, which reaches a depth of 5.6 miles; it’s part of the staggering the Valles Marineris rift valley, which stretches almost 2,500 miles across the surface of the red planet. For comparison’s sake, our earthly Grand Canyon is 1.1 miles deep and 277 miles long.
This remarkable image was taken by the High Resolution Stereo Camera on the European Space Agency’s Mars Express orbiter. In addition to giving us something neat to gawk at, the image also reveals evidence of Mars’s watery past.
Part of the canyon wall collapsed in multiple landslides in the distant past, with debris fanning out into the valley below. Scientists analyzing the texture of the rocks deposited by the landslides say they were transported by liquid water, water ice, or mud. [ScienceNOW]
80beats: NASA’s New Mars Mission: To Study the Mystery of the Missing Atmosphere
80beats: It’s Alive! NASA Test-Drives Its New Hulking Mars Rover, Curiosity
80beats: Vast Ocean May Have Covered One-Third of Primordial Mars
80beats: Mars Rover Sets Endurance Record: Photos From Opportunity’s 6 Years On-Planet
Image: ESA/DLR/FU Berlin (G. Neukum)
All aboard for fake Mars!
Earlier today, a six-man crew battened down the hatches on an 1,800-square-foot module for 520 days of isolation as they pretend to go to Mars and back again. The Mars-500 project, run by the Russian Institute for Biomedical Problems (IBMP) and funded in part by the European Space Agency, hopes to test the psychological mettle required for such a journey.
“See you in 520 days!” shouted Russia’s Sukhrob Kamolov as he was sealed inside the simulator at around 1000 GMT. [Radio Free Europe/Radio Liberty]
The trip will have three stages, including the trip to and from Mars and a simulated landing and planet exploration.
Psychologists said the simulation can be even more demanding that a real flight because the crew won’t experience any of the euphoria or dangers of actual space travel. They have also warned that months of space travel would push the team to the limits of endurance as they grow increasingly tired of each other. [AP]
For lovers of stellar beauty, the Herschel space telescope may have already earned its keep. Just one year after its launch, researchers from the European Space Agency have released this stunning image of a massive star being born in a vast bubble of cold dust.
Herschel’s far-infrared detectors are finely attuned to stellar nurseries. When a star begins to form, the dust and gas surrounding it heats up to a few tens of degrees above absolute zero, and it begins to emit far-infrared wavelengths. In the galactic bubble shown, known as RCW 120, the newborn star is the white blob at the bottom of the bubble.
The “baby” star is perhaps a few tens of thousands of years old. It is some eight to 10 times the mass of our Sun but is surrounded by about 200 times as much material. If more of that gas and dust continues to fall in on the star, the object has the potential to become one of the Milky Way Galaxy’s true giants [BBC].
Giant stars pose a particular challenge to our understanding of star formation, researchers say. Present theories suggest that stars that are larger than about 10 solar masses shouldn’t exist, because their fierce radiation should blast away the clouds that feed them materials to grow on. Yet astronomers have spotted stars that have 120 times the mass of our Sun.
Click through the gallery for a couple more amazing shots from Herschel.
The European Space Agency has released the latest pictures of the Martian moon Phobos, taken by the European Mars Express (MEX) probe during its recent flybys. On one flyby, MEX skimmed just 42 miles above the surface of Phobos, which is the closest any manmade object has ever gotten to the little Martian moon.
The image above is from a flyby that brought MEX within 63 miles of the surface; its High Resolution Stereo Camera took photographs that have a resolution of 14 feet per pixel. The images are being scrutinized by the Russian space agency as it tries to settle on a landing site for its ambitious Phobos-Grunt mission next year–the two potential landing sites are marked by red dots in the picture above. The Phobos-Grunt mission aims to collect a soil sample from Phobos, and then to return the sample to Earth for analysis.
Engines powered by chemical fuel? How passé. For the spacecraft with truly modern flair, an ion thruster is the only way to go. Such a system might not provide powerful and dramatic bursts of speed, but space agencies around the world are recognizing the benefits of its slow-and-steady approach, which is just what’s needed for cruising between planets.
Ion propulsion works by electrically charging, or ionizing, a gas and accelerating the resulting ions to propel a spacecraft. The concept was conceived more than 50 years ago, and the first spacecraft to use the technology was Deep Space 1 in 1998. Since then … there have only been a few other noncommercial spacecrafts that have used ion propulsion [Technology Review]. However, the technology has a clear advantage over chemical propulsion when it comes to long distance missions, because a very small amount of gas can carry a spacecraft a long way. Astronautics expert Alexander Bruccoleri explains that with chemical propulsion, “You are limited in what you can bring to space because you have to carry a rocket that is mostly fuel” [Technology Review].
Now, a European Space Agency (ESA) probe will use four ion thrusters to scoot all the way to Mercury, the planet nearest to the sun. That mission won’t launch until 2014, but ESA officials say the $37 million propulsion system will be the most efficient yet, and will also be the most ambitious test of the technology to date. The Mercury probe will be launched by a conventional rocket, and will continue to use chemical propulsion until it’s out of Earth orbit. When it begins its six-year cruise to Mercury, though, its ion thrusters will kick in. The system will draw electricity from solar panels; as the xenon ions pass through the electrified grids they accelerate to up to 50km a second (31 miles per second) and shoot from the rear in a parallel beam. On Earth, at sea level, the thrust would be just enough to lift a pound coin. In space, however, the same thrust will create a much much bigger lift [Telegraph].
Yesterday, Russian engineers cracked the wax seal on a metal hatch, and six men emerged from the simulated space capsule where they had spent the last 105 days in experiment designed to simulate the isolation of a manned trip to Mars. The experiment is part of a larger project dubbed “Mars 500.” The three months the men spent in isolation are a precursor to another simulation to take place in 2010, when another crew will submit themselves to 520 days in isolation, the projected time it would take for a return trip to Mars [ABC News].
The four Russians, one German, and one Frenchman were chosen from among 6,000 applicants, and were paid about $21,000 each for participating. Inside the mock capsule, they conducted experiments to test their physical and psychological reactions to the isolation, and performed many of the tasks that would keep Mars-bound astronauts busy. They had no television or Internet and their only link to the outside world was communications with the experiment’s controllers — who also monitored them via TV cameras — and an internal e-mail system. Communications with the outside world had 20-minute delays to imitate a real space flight [AP].
A European spacecraft that has been peering through the thick, roiling clouds of Venus for the past three years has found further evidence that the inhospitable planet once had oceans, volcanoes, and a system of plate tectonics similar to those at work on Earth. The Venus Express has mapped the planet’s southern hemisphere using infrared imaging, and found heat variations in the surface rocks, which allows researchers to speculate on the chemical composition of those rocks. Different surfaces radiate different amounts of heat at infrared wavelengths due to a material characteristic known as emissivity, which varies in different materials [SPACE.com].
In certain highland areas, researchers detected cooler patches of rock whose thermal signatures resemble those of granites on Earth. On our own planet, granites are made during the process of rock recycling that goes on at the edges of the great geologic plates that cover the Earth. At the boundaries of these plates, ancient rock is pulled deep into the planet, reworked with water and then re-surfaced at volcanoes. Critically, then, if there is granite on Venus, there must also have been an ocean and a process of plate movement in the past [BBC News].
The European Space Agency’s Planck observatory has reached its operating temperature of a mere tenth of a degree above the lowest temperature theoretically possible given the laws of physics, known as absolute zero. That means it’s ready for its mission: Observing the oldest light in the universe, known as the cosmic microwave background, or CMB, to create the clearest picture yet of what the young universe looked like.
Although scientists have achieved temperatures closer than this to absolute zero in the laboratory, the spacecraft is likely the coldest object in space. Such low temperatures are necessary for Planck’s detectors to study the Cosmic Microwave Background by measuring its temperature across the sky. Over the next few weeks, mission operators will fine-tune the spacecraft’s instruments. Planck will begin to survey the sky in mid-August [SPACE.com], and the first batch of data is expected to be released next year. Planck was launched May 14 and will observe the CMB from a spot more than 930,000 miles from Earth.
The solar probe Ulysses has circled the sun for more than 18 years–almost as long as the Greek hero Odysseus, also called Ulysses, was absent from home due to the Trojan War and his prolonged journey home–but the space probe doesn’t have a homecoming in its future. Ulysses will receive its final transmission tomorrow, as researchers say the scientific findings sent home by the failing spacecraft no longer justify the mission’s costs. After shut-off, Ulysses will continue to orbit the Sun, becoming in effect a man-made ‘comet’. “Whenever any of us look up in the years to come, Ulysses will be there, silently orbiting our star, which it studied so successfully during its long and active life” [SPACE.com], says mission manager Richard Marsden.
The craft has already exceeded expectations. In February 2008, mission engineers announced with great solemnity and with heaps of praise for the orbiter that the craft would fall silent within a few months. Its power supply had grown too weak to keep the craft’s fuel lines from freezing. Not so fast: Engineers figured out that they could keep the lines warm by firing the craft’s thrusters in short bursts every couple of hours [The Christian Science Monitor]. Using that clever fix, Ulysses soldiered on for another year.