Posted on by Nancy Atkinson

Take Up a Collection For NASA

A NASA contractor needs urine. And lots of it, too, about 30 liters (8 gallons) a day, even on weekends. All the details, if you need to know or need to go, of how to collect the specimens are over at SpaceRef, but the quick scoop is that contractor Hamilton Sundstrand is seeking urine from workers at the Johnson Space Center. The company is working on the new Orion space capsule that will replace the shuttle and eventually take astronauts to the moon. This is nothing new. NASA has a long-standing tradition of collecting samples from its workers to help design better space toilets because “you can’t make fake urine,” said John Lewis, NASA’s head of life support systems for Orion.

The contractor is working on how to deal with pee up in space and on the moon. “Urine is a mess because urine is full of solids,” said Lewis. Those solids clog the venting system for dumping pee, so keeping the waste disposal system clear is “really a challenge,” he said.

Here’s an article we did a few months ago about recycling urine on long duration space flights.

An email soliciting urine was sent out to JSC employees, but wasn’t meant to go public, Lewis said. In part the email said:

The Orion Program will be holding a urine collection study starting Monday, July 21 and running through Thursday, July 31, 2008. We are looking for donors as we need to collect a large amount of urine per day for the entire 11 day period. Please contact [deleted] at [deleted]@hs.utc.com to express interest in donating or to get answers to any questions you have regarding the study. We will be hosting an informational meeting with encouraged attendance for potential urine donors from 11-11:30 a.m. Thursday, July 17, 2008 in the first floor conference room. In this meeting we will go over instructions and guidelines for the study and introduce volunteers to the equipment that will be used in the study. If you are unable to attend this meeting due to scheduling conflicts, we can set up another time to clarify the study operations on an individual basis.”

Again, if you need to know more, see the entire email here.

Don’t we just love to read other people’s mail?

Original News Sources: CNN, NASA Watch

Posted on by Jerry Coffey

Diameter of the Solar System

Artist's impression of the Oort Cloud. (NASA/JPL)

Defining the diameter of the Solar System is a matter of perspective and characterization. You can look at the Solar System’s diameter as ending at the aphelion of the orbit of the farthest planet, the edge of the heliosphere, or ending at the farthest observable object. To cover all of the objective bases, we will look at all three.

Looking at the aphelion(according to NASA figures) of the orbit of the farthest acknowledged planet, Neptune, the Solar System would have a radius of 4.545 billion km and a 9.09 billion km diameter. This diameter could change if the dwarf planet Eris is promoted after further study.

Sedna is three times farther away from Earth than Pluto, making it the most distant observable object known in the solar system. It is 143.73 billion km from the Sun, thus giving the Solar System a diameter of 287.46 billion km. Now, that is a lot of zeros, so let’s simplify it into astronomical units. 1 AU(distance from the Earth to the Sun) equals 149,597,870.691 km. Based on that figure, Sedna is nearly 960.78 AU from the Sun and the Solar System is 1,921.56 AU in diameter.

A third way to look at the diameter of the Solar System is to assume that it ends at the edge of the heliosphere. The heliosphere is often described as a bubble where the solar wind pushes against the interstellar medium and edge of where the Sun’s gravitational forces are stronger than those of other stars. The heliopause is the term given as the edge of that influence, where the solar wind is stopped and the gravitational force of our Sun fades. That occurs at about 90 AU, giving the Solar System a diameter of 180 AU. If the Sun’s influence ends here, how could Sedna be considered part of the Solar System, you may wonder. While it is beyond the heliopause at aphelion, it falls back within it at perihelion(around 76 AU).

Those determinations of the diameter of the Solar System may seem about as clear as mud, but they give you an idea of what scientists are trying to place a definitive value on. The distances involved are mind boggling and there are too many unknowns to place a absolute figure. Perhaps, an exact number will be determinable as the Voyager probes continue their outward journey.

Here’s an article on Universe Today about the closest star to Earth, and another about how long it would take to travel to the closest star.

Here’s an article from the Physics Factbook about the diameter of the Solar System, and a cool way to visualize it using the Earth as a peppercorn.

We have recorded a whole series of podcasts about the Solar System at Astronomy Cast. Check them out here.

References:
Neptune Fact Sheet
NASA: Planet-Like Body Discovered at Fringes of Our Solar System
NASA Science: Heliophysics
Wikipedia

Posted on by Jerry Coffey

How Many Stars are in the Solar System?

Red Dwarf star and planet. Artists impression (NASA)

The answer to ‘how many stars are in the Solar System’ is pretty straightforward, or is it? There is only one star that has ever been observed in our solar system, but some scientists have theorized that there is a second star out beyond the Oort Cloud that only comes close enough to be observed every 32 million years. That length of time between observational periods would explain why a human has never proven its existence.

As scientists explore our galaxy, it seems that ours is a somewhat unique solar system in many ways. Most do not have as many orbiting bodies and very few are single star systems. A majority have at least two stars(binary). A system could theoretically have an unlimited amount of stars. Systems with up to six stars have been observed.

Now, a little more about the theoretical companion star within our our solar system. The other star would have to be a red or brown dwarf and has been given the name Nemesis. In 1984, a pair of scientists, Raup & Sepkoski, claimed that mass extinctions, like the one that killed the dinosaurs, occur every 32 million years. The most widely held theory for the demise of dinosaurs is an asteroid or cometary impact, so the length of time would suggest that some mechanism is needed to disturb the comets in the Oort Cloud every 32 million years. Richard Muller, among others, hypothesized that a companion that orbits the Sun in that period could be the explanation. To prove their theory, Muller and a few colleagues embarked on a search for Nemesis. The team ran into this hurdle immediately; ‘Every star of the correct spectral type and magnitude must be scrutinized. … We are currently scrutinizing 3098 fields, which we believe contain all possible red dwarf candidates in the northern hemisphere.’ With nearly 3,100 possibilities in the Northern Hemisphere alone and a limited number of clear observational days, it is easy to see how daunting this task is.

Just to be clear, there is no evidence of any kind that makes scholars think that there is a companion star in our Solar System. It is a theory based solely on a need to explain the periodic mass extinctions that our planet has experienced. So, the only answer to ‘how many stars are in the Solar System’ that can be proven through observation is one…the Sun.

Here’s an article about a possible Planet X, and how it could disrupt the Solar System (and how it probably doesn’t exist), and an article about how multiple star systems come together.

Here’s Wikipedia’s entry on Nemesis, and another answer to the question from NASA.

We have recorded a whole series of podcasts about the Solar System at Astronomy Cast. Check them out here.

References:
NASA Ask an Astrophysicist
Nineplanets.org
Wikipedia

Posted on by Nancy Atkinson

Phoenix’s Rasp Works to Create Ice Shavings

The Phoenix Mars Lander successfully used a rasp on the end of its robotic arm to drill into the frozen soil on Mar’s arctic tundra. This effort loosened the icy material, which was then scraped up and collected in the lander’s scoop. Images and data sent from Phoenix early today indicated the shaved material in the scoop had changed slightly over time during the hours after it was collected, which is a sign that the material includes water ice. Water ice sublimates, or evaporates on Mars surface because of the low surface pressure on the Red Planet. It can exist just under the surface, however, protected by the soil.

The motorized rasp — located on the back of the lander’s robotic arm scoop — made two distinct holes in a trench informally named “Snow White.” The material loosened by the rasp was collected in the scoop and documented by the Robotic Arm Camera. The activity was a test of the rasping method of gathering an icy sample, in preparation for using that method in coming days to collect a sample for analysis in an oven of Phoenix’s Thermal and Evolved-Gas Analyzer (TEGA).

“This was a trial that went really well,” said Richard Morris, a Phoenix science team member from NASA’s Johnson Space Center, Houston. “While the putative ice sublimed out of the shavings over several hours, this shows us there will be a good chance ice will remain in a sample for delivery” to Phoenix’s laboratory ovens.

The motorized rasp bit extends from the back of the scoop on the end of Phoenix’s 2.35-meter-long (7.7-foot-long) robotic arm. The tool works just a rasp for woodworking, which coarsely files or shaves material.

‘While Phoenix was in development, we added the rasp to the robotic arm design specifically to grind into very hard surface ice,’ said Barry Goldstein, Phoenix project manager at NASA’s Jet Propulsion Laboratory, Pasadena, Calif. ‘This is the exactly the situation we find we are facing on Mars, so we believe we have the right tool for the job. Honeybee Robotics in New York City did a heroic job of designing and delivering the rasp on a very short schedule.'”

The past few days, Phoenix used its robotic arm to clear the top layer of dirt from a trench it dug called Snow White. On Tuesday, Phoenix used the rasp to dig into two spots at the bottom of the trench.

Mission scientists have been working on techniques to quickly obtain the sample and then deliver it to the TEGA before too much ice has sublimated away. The TEGA test will “bake” the soil, releaseing gases present to help sciencists learn more about the ice’s composition.

Today, (Wednesday) Phoenix will be commanded to continue scraping and enlarging the “Snow White” trench and to conduct another series of rasp tests. The lander’s cameras will again be used to monitor the sample in the scoop after its collection.

Original News Source: Phoenix Press Release

Posted on by Jerry Coffey

How Old is the Solar System?

Artist's impression of planetary formation. Image credit: NASA

How old is the Solar System? That is a question that cuts to the heart of it all. By studying several things, mostly meteorites, and using radioactive dating techniques, specifically looking at daughter isotopes, scientists have determined that the Solar System is 4.6 billion years old. Well, give or take a few million years. That age can be extended to most of the objects and material in the Solar System.

The United States Geological Survey(USGS) website has a lot of indepth material about how the age of the Solar System was determined. The basics of it are that all material radioactively decays into a stable isotope. Some elements decay within nanoseconds while others have projected half-lives of over 100 billion years. The USGS based their study on minerals that naturally occur in rocks and have half-lives of 700 million to 100 billion years. These dating techniques, known as radiometric dating, are firmly grounded in physics and are used to measure the last time that the rock being dated was either melted or disturbed sufficiently to re-homogenize its radioactive elements. This techniques returned an approximate age for meteorites of 4.6 billion years and Earth bound rocks around 4.3 billion years. The USGS admits that they were unable to find any rock that had not been altered by the Earths tectonic plates, so the age of the Earth could be refined in the future.

When the gasses of the early solar nebula began to cool, the first materials to condense into solid particles were rich in calcium and aluminum. Eventually solid particles of different elements clumped together to form the common building blocks of comets, asteroids, and planets. Astronomers have long thought that some of the Solar System’s oldest asteroids should be more enriched in calcium and aluminum, but, none had been identified until recently. The the Allende meteorite of 1969 was the first to show inclusions that were extremely rich in calcium and aluminum. It took 40 years for the spectra of the inclusions to be discovered and then extrapolates to very old asteroids still in orbit around the Sun. Astronomer Jessica Sunshine and colleagues made this discovery with the support of NASA and the National Science Foundation

Additionally, the Universe is thought to have been created about 13.7 billion years ago. Measuring two long-lived radioactive elements in meteorites, uranium-238 and thorium-232, has placed the age of the Milky Way at in the same time frame. From these measurements, it appears that large scale structures like galaxies formed relatively quickly after the Big Bang.

Here’s an article from Universe Today that gives more information about the radioactive dating process of studying meteorites, and another article about how the solar nebula probably lasted about 2 million years.

Here’s a great article from the USGS that explains how the dating process works, and a great series from UC San Diego.

We have recorded a whole series of podcasts about the Solar System at Astronomy Cast. Check them out here.

References:
U.S. Geological Survey
NASA: How Old is the Universe?
NASA Earth Guide: Age of the Solar System

Posted on by Nancy Atkinson

Colonizing Venus With Floating Cities

Cloud city of Bespin, from Stars Wars. Credit and copyright: Ralph McQuarrie

Seemingly, people in the space community have a tendency to push the boundaries of thought about all the possibilities that await us in the universe. Case in point: Geoffrey Landis. Landis is a scientist at NASA’s Glenn Research Center who writes science fiction in his spare time. Last week Landis shared with us his ideas for using a solar powered airplane to study Venus.

This week, Landis goes a step farther (actually, several steps farther) with his ideas about colonizing Venus. Yes, Venus, our hot, greenhouse-effect-gone-mad neighboring planet with a crushing surface pressure that has doomed the few spacecraft that have attempted to reach the planet’s mysterious landscape. Landis knows Venus’ surface itself is pretty much out of the question for human habitation.

But up about 50 kilometers above the surface, Landis says the atmosphere of Venus is the most Earth-like environment, other than Earth itself, in the solar system. What Landis proposes is creating floating cities on Venus where people could live and work, as well as study the planet below.

“There’s been a lot of people who have been proposing space colonies, such as colonies that are in free space, separate from any planet,” said Landis. “And I said, well, if you’re thinking that far into the future why don’t we think of some more groundbreaking, or perhaps we should say atmosphere-breaking possibilities.”

50 km above the surface, Venus has air pressure of approximately 1 bar and temperatures in the 0°C to 50°C range, a quite comfortable environment for humans. Humans wouldn’t require pressurized suits when outside, but it wouldn’t quite be a shirtsleeves environment. We’d need air to breathe and protection from the sulfuric acid in the atmosphere.

In looking at Venus, the fact that struck Landis the most is that Earth’s atmosphere of nitrogen and oxygen would actually float in Venus’ atmosphere of carbon dioxide. “Because the atmosphere of Venus is CO2, the gases that we live in all the time, nitrogen and oxygen, would be a lifting gas,” he said. “On Earth, we know to get something to lift, you need something lighter than air. Well, on Venus, guess what? Our air is lighter than air, or at least lighter than the Venus atmosphere.”

So, create a bubble, fill it with Earth-like atmosphere, and it would float on Venus. “If you could just take the room you’re sitting in and replace the walls with something thinner, the room would float on Venus,” said Landis.

The biggest challenge would be using a substance resistant to sulfuric acid to form the outer layer of the bubble; ceramics or metal sulfates could possibly serve in this role, but of course, you’d want to be able to see outside, as well. “Just think of the great pictures you could get,” said Landis.

Asked if he has ever thought about terraforming Venus, Landis said, “Oh, yes, of course! That’s one of the reasons I started thinking about the floating cities on Venus. The more you look at Venus, the more you say, ‘oh my goodness, terraforming would be a really hard project.'”

Back in about 1962 when Carl Sagan first talked about the concept of terraforming Venus, it wasn’t known what a challenge Venus would be.

“They didn’t quite know how difficult Venus is, they didn’t know how thick the atmosphere was on Venus and how hot it was,” said Landis. “They knew it had a greenhouse effect, but they didn’t know how bad. But the more we look at the problems, the more we say, goodness, terraforming is a very difficult proposition.”

But Landis thinks Venus already has a very nice environment.

“What I like to say, the problem with Venus is if you define sea level as the place in the atmosphere where it’s the same as Earth, the place of “sea level” on Venus is just too far above the ground.”

While Landis’ plans for a solar powered airplane are a true possibility for an upcoming mission to Venus, his ideas about colonizing that planet are a little more speculative. “This is really just a thought exercise,” said Landis, “an exercise in imagination rather than something we’re likely to do in the near term. I don’t expect people will be building cities on Venus, at least probably not in this century.”

Anyone having visions of Bespin and Lando Calrissian from “The Empire Strikes Back”?

Maybe that should be “Landis” Calrissian.

More information about Geoffrey Landis.

Posted on by Fraser Cain

Formation of the Solar System

Artist's impression of planetary formation. Image credit: NASA

Where did the Solar System come from? How did we go from space to a star with planets orbiting around it? Before we can look at the formation of the Solar System, we have to see what this region looked like.

Throughout the Milky Way, there are clouds of cold gas and dust, just sitting there, doing nothing. At some point in the distant past, this cloud was disturbed; either through the collision of another galaxy, or the explosion of a massive star.

The explosion would have sent waves through space that squeezed the gas and dust together. The clumping material was able to attract more material with its gravity, and started to collect into the solar nebula. The mutual movement of all the atoms in the cloud gave the solar nebula a direction to spin.

The Sun formed out of the largest collection of mass at the center of the solar nebula. Because it was spinning quickly, the rest of the nebula collected into a flattened disk around the newborn Sun – astronomers call this an accretion disk. Within the accretion disk, additional clumps gathered together; these would eventually form the planets.

The planets started out as tiny specks of dust that clumped together. As they continued to gather together, they became pebbles, rocks, boulders and eventually planetoids. These planetoids violently collided together to become the planets we know today.

By studying the decay of radioactive elements in meteorites, astronomers have been able to determine that the Solar System formed about 4.6 billion years ago.

When astronomers look out into the Universe, they see other Solar Systems forming at different stages. Some are large clouds of cold dust, others are starting to collapse. Others have accretion disks, and some might even have planets clearing out paths in the dust of the disk. We can’t see the formation of our own Solar System, but we can see it happening everywhere we look, so we assume our Solar System formed in the same way.

Here’s an article from Universe Today about planetary formation, and another about how the gas giants might have formed quickly.

Here’s an article from Wikipedia about the formation of the Solar System, and a link to NASA’s Solar System Simulator.

We have recorded a whole series of podcasts about the Solar System at Astronomy Cast. Check them out here.

Posted on by Nancy Atkinson

New Evidence for a Wetter, Warmer Ancient Mars

A 3-D image of a trough in the Nili Fossae region of Mars shows phyllosilcates (in magenta and blue hues) on slopes of mesas and canyon walls, showing water played a role in Mars’ past.

For all the Mars romanticists out there, we (yes, that means me, too) hope and maybe even dream that Mars once harbored water. And not just a little spurt of groundwater every once in awhile; we want the water to have been there in abundance and for enough time to make an impact on the planet and its environment. Now, proof of copious amounts of water in Mars’ past may have been found. Two new papers based on data from the Mars Reconnaissance Orbiter (MRO) found that vast regions of the ancient southern highlands of Mars hosted a water-rich environment, and that water played a sizable role in changing the minerals of a variety of terrains in the Noachian period – about 4.6 billion to 3.8 billion years ago.

John Mustard, a professor of planetary geology at Brown University and deputy principal investigator for the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) on MRO investigated the pervasive presence of phyllosilicates, clay-like minerals that preserve a record of water’s interaction with rocks.

Specifically, Mustard and his team from 13 other institutions focused on phyllosilicate deposits in areas like craters, valleys and dunes all over the planet. Among the highlights, he detected the clay-like minerals in fans and deltas within three regions, most notably the Jezero crater. That discovery marks the first time hydrated silicates have been found in sediments “clearly lain by water,” Mustard said.

The team also found phyllosilicate deposits in thousands of places in and around craters, including the pointed peaks located at the center of some of the depressions. This suggests that water was present 4-5 kilometers below the ancient Martian surface, the team wrote, due to the generally accepted principle that crater-causing collisions excavate underground minerals that are then exposed on the crater peaks.

“Water must have been creating minerals at depth to get the signatures we see,” Mustard said.

The clay minerals were formed at low temperatures (100-200°C) – an important clue to understanding the Red Planet’s potential for habitability during the Noachian period.

“What does this mean for habitability? It’s very strong,” Mustard said. “It wasn’t this hot, boiling cauldron. It was a benign, water-rich environment for a long period of time.”

In another paper, graduate student Bethany Ehlmann and colleagues from Brown and other institutions analyzed sediment deposits in two exquisitely preserved deltas in the Jezero crater, which held an ancient lake slightly larger than Lake Tahoe. The deltas suggest a flow from rivers carrying the clay-like minerals from an approximate 15,000-square kilometer watershed during the Noachian period.
Ehlmann said scientists cannot determine whether the river flow was sporadic or sustained, but they do know it was intense and involved a lot of water.

The deltas appear to be excellent candidates for finding stored organic matter, Ehlmann said, because the clays brought in from the watershed and deposited in the lake would have trapped any organisms, leaving in essence a cemetery of microbes.

“If any microorganisms existed on ancient Mars, the watershed would have been a great place to live,” Ehlmann said. “So not only was water active in this region to weather the rocks, but there was enough of it to run through the beds, transport the clays and run into the lake and form the delta,” she said.

Original News Source: Brown University Press Release

Posted on by Ian O'Neill

Griffin: China Could Beat US in Moon Race

Long March II F rocket carrying Chinas second manned spacecraft Shenzhou VI in 2005 (Xinhua)

More bad news for NASA: even their administrator thinks China could beat the US to the Moon. Speaking with the BBC today, Michael Griffin shared his views about the Chinese space aspirations, pointing out that the super-state could, if they wanted to, send a manned mission to the lunar surface within a decade. NASA’s return mission to the Moon is planned to launch, at the earliest, in 2020, so this news is bound to knock the wind out of the US space agency’s hopes to continue where it left off in 1972…

In the last five years, China has been teetering on the edge of a full-manned space program. In 2003, the nation became only the third country to put a national into space (following the Russia and the USA), blasting Yang Liwei into orbit for 21 hours on the Shenzhou 5 spacecraft. Shenzhou 6 was launched with two astronauts (or “taikonauts”) on board, spending five days orbiting the Earth in 2005. This year, shortly after the Beijing Olympics in October, China is sending another manned mission into orbit, only this time it is hoped a spacewalk will be possible. With this rapid succession of successful manned launches, it comes as no surprise that attention is swinging away from NASA and to China for the next big step into space.

The last time man set foot on the Moon was in 1972 when Eugene Andrew Cernan, last man on the Moon, boarded the Apollo 17 lunar module. That was 36 years ago and space flight has changed significantly since then, now NASA has more competition, as highlighted by Griffin during a visit to London:

“Certainly it is possible that if China wants to put people on the Moon, and if it wishes to do so before the United States, it certainly can. As a matter of technical capability, it absolutely can.” – Dr Michael Griffin

As to whether it actually matters whether China are the next to land on the Moon is open to interpretation. After all, the first nation to set foot on Earth’s natural satellite was the USA, so is a return trip a big psychological “victory” for China? “I’m not a psychologist, so I can’t say if it matters or not. That would just be an opinion and I don’t want to air an opinion in an area that I’m not qualified to discuss,” Griffin added.

Recently, there has been increased cooperation between the US and China when sharing science and information. “We do have some early co-operative initiatives that we are trying to put in place with China, mostly centred around scientific enterprises. I think that’s a great place to start,” he said. Although many will view an early Chinese lunar mission as a NASA failure, both nations appear to be trying to forge close relationships that could possibly lead to joint space missions in the future. After all, even at the peak of the Cold War, the US and Russia began working on a common goal.

“I think we’re always better off if we can find areas where we can collaborate rather than quarrel. I would remind your [audience] that the first US-Soviet human co-operation took place in 1975, virtually at the height of the Cold War. And it led, 18 years later, to discussions about an International Space Station (ISS) programme in which we’re now involved.” – Dr Michael Griffin

Regardless of who gets to the Moon first, Griffin will be feeling the pressure of the “five-year gap” between the Shuttle being retired in 2010 and Constellation completion in 2015, there is still little alternative than relying on Russia and Europe for US access to space. Griffin has tried to increase Constellation funding by $2bn to bring completion forward by a year, but the application was quickly turned down by Congress. Those five long years may be more costly than the US government realizes as NASA loses more footing in manned access to space…

Source: BBC

Posted on by Ian O'Neill

What’s the Weather Like on Extrasolar Planet HD 189733b?

An artists impression of HD 189733b, a configuration that matches the predictions of Spitzer observations (NASA)

HD 189733b is a Jupiter-sized extrasolar planet orbiting a yellow dwarf star. Due to its size and compact orbit, HD 189733b is one of the most studied extrasolar planets. HD 189733b shares many similar characteristics as HD 209458b (a.k.a. “Osiris,” as I reported in a UT article yesterday), and similar techniques have been used to analyse the spectral emissions from both parent stars. Although HD 189733b’s atmosphere isn’t thought to be evaporating like Osiris’, atmospheric gases extend far beyond the planetary “surface” allowing stellar light to pass through, giving astronomers a peek into what chemical compounds surround HD 189733b. From this analysis, scientists have deduced that water and methane is contained in the atmosphere; the Spitzer space telescope has even mapped the temperature distribution around the globe. Now, an Indian researcher has published work indicating a thin layer of particles exists in the upper atmosphere of HD 189733b. So what is the weather like on HD 189733b?

HD 189733b was discovered in 2005 and orbits a star in a binary system called HD 189733 in the constellation of Vulpecula. As the main star in the binary is a variable star (due to the transit of HD 189733b, periodically eclipsing the star), it has been designated with the variable name V452 Vulpeculae. The star system itself is located near the Dumbell Nebula, approximately 62 light years from Earth. As the star is relatively dim, as the exoplanet transits the star, there is an appreciable decrease in luminosity (of about 3%), creating the ideal conditions for the atmosphere of HD 189733b to be studied.

This exoplanet is approximately the same mass (1.15 ± 0.04 MJ) and radius (1.154 ± 0.032 RJ) as Jupiter, but it orbits very close to its parent star (~0.03 AU) so it is known as a “Hot Jupiter.” Due to the water/methane mix in the planet’s atmosphere, it is believed HD 189733b may have a blue hue, much like the colour of Uranus.

Spitzer temperature map of HD 189733b (NASA)

In 2007, the Spitzer Space Telescope observed HD 189733b and compiled a temperature map of the planet, showing that the equator was much hotter than the poles. Astronomers were also able to deduce that the atmosphere contains iron, silicate and aluminium oxide particulates. In new research by Sujan Sengupta from the Indian Institute of Astrophysics in Bangalore, it appears that these particles may collect in the upper atmosphere, forming a thin haze. This tentative conclusion was reached after careful examination of the polarization of emission from the star as HD 189733b transited. Preliminary results suggest there is a thin, reflective cloud in the exosphere.

So what is the weather like on HD 189733b? Hot and cloudy.

Source: arXiv Blog
Paper: arXiv:0807.1794v1 [astro-ph]