Top Astronomy Events Coming Up in 2012

Stargazing Credit: http://twitter.com/VirtualAstro

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As 2011 is drawing to a close, the festive season is here and many of us are winding down and looking forward to the holidays. But this is a great time to look ahead to 2012 and pencil into our calendar and diaries the top astronomical events we don’t want to miss next year.

2012 is going to be a great year for astronomy observing, with some rare and exciting things taking place and a good outlook with some of the regular annual events.

So what top wonders should we expect to see and what will 2012 bring?

Conjunction of Venus and Jupiter

Venus & Jupiter Conjunction Credit: Anthony Arrigo UtahSkies.org

On March 15th the Planets Venus and Jupiter will be within 3 degrees and very close to each other in the early evening sky. This will be quite a spectacle as both planets are very bright (Venus being the brightest) and the pair will burn brightly together like a pair of alien eyes watching us after the Sun sets.

This conjunction (where planets group close together as seen from Earth) will be a fantastic visual and photographic opportunity, as it’s not often you get the brightest Planets in our Solar System so close together.

Transit of Venus

Transit of Venus Credit: Australian Space Alliance

For many, the transit of Venus is the year’s most anticipated astronomical event and it takes place on June 5th – 6th. The Planet Venus will pass between the Earth and the Sun and you will see Venus (a small black circle) slowly move across, or “transit” the disc of the Sun.

Transits of Venus are very rare and only a few have been witnessed since the dawn of the telescope. Be sure not to miss this very rare event as the next one isn’t visible for over another 100 years from now in 2117 and the next after that is in 2125.

The full transit of Venus in 2012 will be visible in North America, the northwest part of South America, Western Pacific, North East Asia, Japan, Australia and New Zealand. Other parts of the world will see a partial transit such as observers in the UK, who will only be able to see the last part of the transit as the Sun rises.

First contact will be at 22:09 UT and final contact will be at 04:49 UT

Take note! You have to use the right equipment for viewing the Sun, such as eclipse glasses, solar filters, or projection through a telescope. Never ever look directly at the Sun and never look at it through a normal telescope or binoculars – You will be permanently blinded! The transit of Venus will be a very popular event, so contact your local astronomy group and see if they are holding an event to celebrate this rare occasion.

Meteor Showers

Don't Miss the Major 2012 Meteor Showers Credit: Shooting Star Wallpapers

2011 was a poor year for meteor showers due to the presence of a largely illuminated Moon on all of the major showers; this prevented all but the brightest meteors being seen.

In contrast 2012 brings a welcome respite from the glare of the Moon as it gives little or no interference with this year’s major showers. The only other issue left to contend with is the weather, but if you have clear skies on the evenings of these celestial fireworks, you are in for a treat.

  • The Quadrantid Meteor Shower peak is narrow and just before dawn on January 4th this shower is expected to have a peak rate (ZHR) of around 80 meteors per hour.
  • The Perseid Meteor Shower peak is fairly broad with activity increasing on the evenings of the August 9th and 10th with the showers peak on the morning of the 12th. Perseids are the most popular meteor shower of the year as it tends to be warm and the shower has very bright meteors and fireballs, with rates of 100+ an hour at its peak.
  • The Geminid Meteor Shower is probably the best meteor shower of the year with high rates of slow bright meteors. The peak is very broad and rates of 100+ meteors per hour can be seen. The best time to look out for Geminids is on the evenings of the 12th to 14th December, but they can be seen much earlier or later than the peak.

If you want to find out more and enjoy the meteor showers of 2012, why not join in with a meteorwatch and visit meteorwatch.org

Jupiter and the Moon

Occultation of Jupiter by the Moon on July 15th as seen from Southern England Credit: Adrian West

European observers are in for a very rare treat as the Moon briefly hides the planet Jupiter on the morning of July 15th. This “lunar occultation” can be seen from southern England and parts of Europe at approximately 1:50am UT (dependant on location) and the planet re-emerges from the dark lunar limb at approximately 3:10am UT.

This is a great chance to watch this rare and bright event, and it will also be a fantastic imaging opportunity.

Annular Eclipse

Annular Eclipse Credit: Kitt Peak Observatory

American observers will have treat on May 20th with an annular eclipse of the Sun. The eclipse will be visible from many western US states and a partial eclipse visible from most of North America.

Because the Moon’s orbit is not a perfect circle and is slightly elliptical, it moves closer and further away from us slightly in its orbit by 13% and on July 15th it is at its furthest point away from the Earth as it passes in front of the Sun.

Normally the Moon covers the entire disc of the Sun and creates a total solar eclipse, but because the Moon is at its furthest point in its orbit on the 15th, we get an annular eclipse, where we can still see a ring of bright light around the Sun, but we don’t get totality.

The eclipse starts roughly at 6:20pm local time for the Western US states and lasts for four and a half minutes.

As mentioned earlier; never, ever look at the Sun without proper protection such as eclipse glasses or filters for equipment! This can damage your eyes and permanently blind you. This is the same for cameras; the sensitive chips inside can be damaged.

The World Not Ending

End Of The World

Finally we get to December 21st, in which astronomy-minded folks will celebrate the solstice. But in case you haven’t heard, some have prophesied the end of the world, saying the Mayan calendar ends. This has been the subject of much discussion, comedy and media coverage, and it has even been made into films.

Will the Antichrist press the red button and will there be the Rapture? Will the Earth reverse its magnetic poles, or will we get wiped out by a solar flare, rogue comet or asteroid?

Nope, probably not. You can read our entire series which explains why this whole 2012 end-of-the-world craze is complete hokum.

All I know is 2012 is going to be a great year for astronomy with some very interesting, rare events taking place, with many more regular events to see, as well.

I’m sure it’s not going to end.

 

Missions that Weren’t: NASA’s Manned Mission to Venus

Venus. Image Credit: NASA/courtesy of nasaimages.org

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In the mid-1960s, before any Apollo hardware had flown with a crew, NASA was looking ahead and planning its next major programs. It was a bit of a challenge. After all, how do you top landing a man on the Moon? Not wanting to start from scratch, NASA focused on possible missions that would use the hardware and software developed for the Apollo program. One mission that fit within these parameters was a manned flyby of our cosmic twin, Venus. 

As one of our neighbouring planets, a mission to Venus made sense; along with Mars, it’s the easiest planet to reach. Venus was also a mystery at the time. In 1962, the Mariner 2 spacecraft became the first interplanetary probe. It flew by Venus, gathered data on its temperature and atmospheric composition before flying off into a large heliocentric orbit. But there was more to learn, making it a destination worth visiting.

A scale comparison of terrestrial planets Mercury, Venus, Earth, and Mars. That Earth and Venus are of a similar size led many to draw comparisons between the planets before better scientific experiments revealed Venus is closer to the Earth inside out. Image Credit: NASA/courtesy of nasaimages.org

But beyond being relatively practical with great potential for scientific return, a manned mission to Venus would prove that NASA’s spacecraft and astronauts were up for the challenges of long-duration interplanetary flight. In short, it would give NASA something exciting to do.

The mission proposal was published early in 1967. It enhanced the Apollo spacecraft with additional modules, then took the basic outline of an Apollo mission and aimed it towards Venus instead of the Moon.

The crew would launch on a Saturn V rocket in November of 1973, a year of minimal solar activity. They would reach orbit in the same Command and Service Modules (CSM) that took Apollo to the Moon. Like on Apollo, the CSM would provide the main navigation and control for the mission.

Going to the Moon, Apollo missions had the crew turn around in the CSM to pull the LM out of its launch casing. On the mission to Venus, the crew would do the same, only instead of an LM they would dock and extract the Environmental Service Module (ESM). This larger module would supply long-duration life support and environmental control and serve as the main experiment bay.

An artist's impression of the Mariner 2 probe. Image Credit: NASA/courtesy of nasaimages.org

With these two pieces mated, the upper S-IVB stage of Saturn V would propel the spacecraft towards Venus. Once its fuel store was spent, the crew would repurpose the S-IVB into an additional habitable module. Using supplies stored in the ESM, they would turn the rocket stage into their primary living and recreational space. On its outside, an array of solar panels would power each piece of the spacecraft throughout the mission.

The crew would spend 123 days traveling to Venus. Ten hours of each day would be dedicated to science, mainly observations of the solar system and beyond with a telescope mounted in the ESM. UV, X-ray, and infrared measurements could create a more complete picture of our corner of the universe. The rest of each day would be spent sleeping, eating, exercising, and relaxing — a full two hours of every day would be dedicated to unstructured leisure, a first for astronauts.

Like Mariner 2 before them, the crew would flyby Venus rather than go into orbit. They would only have 45 minutes to do close optical observations and deploy probes that would send back data on the Venusian atmosphere in realtime.

After the flyby, the spacecraft would swing around Venus and start its 273 day trip back to Earth. Like on an Apollo lunar mission, the crew would transfer back into the Command Module before reentry taking anything that had to return to Earth with them. They would jettison the S-IVB, the ESM, and the Service Module, switch the CM to battery power, and plunge through the atmosphere. Around December 1, 1974, they would splashdown somewhere in the Pacific Ocean.

Though worked out in great detail, the proposal was a thought experiment rather than something NASA was seriously considering. Nevertheless, Apollo-era technology would have managed the mission.

Source: NASA Manned Venus Flyby Study

The surface of Venus as captured by Soviet Venera 13 lander in March of 1982. NASA/courtesy of nasaimages.org

Venus Express Discovers Venusian Ozone Layer

Venus Express has two solar cell panels per wing comprising alternating rows of standard triple junction solar cells as well as highly reflective mirrors to reduce the operating temperatures. There is twice as much sunlight in Venus's orbit as there is in Earth's orbit, plus additional thermal input from the Venusian surface and atmosphere – 75% of sunlight being reflected up from it. In certain cases, this results in Venus Express receiving an equivalent of the thermal input from 3.5 Suns. Credit: ESA

Every day brings on new discoveries and now ESA’s Venus Express spacecraft has delivered another… the red-hot planet has an ozone layer. Located high in the Venusian atmosphere, this planetary property will help us further understand how such features compare to Earth and Mars – along with refining our search for extra-terrestrial life.

This wonderful discovery was made while Venus Express was busy watching stars at the periphery. When seen through the planet’s atmosphere, the SPICAV instrument was able to distinguish gas types spectroscopically. By picking apart the wavelengths, ozone was detected through its absorption of ultraviolet light. It forms when sunlight breaks down the carbon dioxide molecules and releases oxygen. From there, they are distributed by planetary winds where the oxygen atoms will either combine into two-atom oxygen molecules, or form three-atom ozone.

“This detection gives us an important constraint on understanding the chemistry of Venus’ atmosphere,” says Franck Montmessin, who led the research.

This is an animation of Venus Express performing stellar occultation at Venus. Venus Express is the first mission ever to apply the technique of stellar occultation at Venus. The technique consists of looking at a star through the atmospheric limb. By analysing the way the starlight is absorbed by the atmosphere, one can deduce the characteristics of the atmosphere itself. Credits: ESA (Animation by AOES Medialab)

To date, ozone has been the sole property of Earth and Mars – but this type of discovery method could aid astronomers in searching for life on other worlds. Why is it important? Because ozone absorbs most of the Sun’s harmful ultra-violet rays… and because it is believed to be a by-product of life itself. When combined with carbon dioxide, this could create a signature as a strong signal for life. But don’t get too excited at the prospects, yet. The amount of ozone detected is also critical to refining models. It will need to be at least 20% of Earth’s value to even be considered.

“We can use these new observations to test and refine the scenarios for the detection of life on other worlds,” says Dr Montmessin.

While we know that chances are almost non-existent that Venus has life, it still brings it one step closer to planets like Mars and Earth.

“This ozone detection tells us a lot about the circulation and the chemistry of Venus’ atmosphere,” says Hakan Svedhem, ESA Project Scientist for the Venus Express mission. “Beyond that, it is yet more evidence of the fundamental similarity between the rocky planets, and shows the importance of studying Venus to understand them all.”

Original Story Source: ESA Space Science News.

New Research Finds Venus’ Winds, They Are A-Changin’

Image of Venus in ultraviolet light by ESA's Venus Express.

 

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Venus, Earth’s hotheaded neighbor, may have more variability in its weather patterns than previously believed. Using infrared data obtained by ground-based telescopes in Hawaii and Arizona researchers have found that Venus’ mesosphere and thermosphere are less consistent in temperature than layers closer to its surface.

But first let’s talk about Venus itself.

Possibly the most inhospitable of planets in our solar system, Venus is the victim of a runaway greenhouse effect. Our neighboring world is a virtual oven… with a rocky surface baked by 800ºF temperatures and crushed beneath the weight of its own incredibly dense atmosphere, standing “sea level” on Venus would be like being 3,300 feet underwater, just in terms of pressure per square inch. And as if the heat and pressure weren’t enough, Venus’ skies are full of clouds made of corrosive sulphuric acid, lit by bolts of lightning and and whipped along by hurricane-force planetwide winds. All Earth-based probes that have ever landed there only lasted moments on the surface before succumbing to Venus’ destructive environment.

Venus is, quite literally, hellish.

Venus' south polar vortex imaged in infrared. A darker region corresponds to higher temperature and thus lower altitude. Credit: ESA/VIRTIS/INAF-IASF/Obs. de Paris-LESIA.

Unlike Earth, Venus does not have much of an axial tilt. This means there’s little, if any, seasonal variation on Venus. (Actually it does have a tilt… Venus is rotated almost completely upside-down relative to its poles, and so in effect still has very little axial tilt.) And since its cloud cover is so dense and it lacks a hydrologic cycle to move heat energy around, it pretty much stays at a constant level of “extreme broil” all across Venus’ surface.

Surface weather on Venus, although unpleasant, is consistent.

Yet based on an international team’s new research this is not the case higher up in Venus’ atmosphere. A new look at old data has uncovered changing weather patterns visible in infrared light at about 68 miles (110 kilometers) above the planet’s surface in the cold, clear air above the acid clouds.

“Any variability in the weather on Venus is noteworthy, because the planet has so many features to keep atmospheric conditions the same,” said Dr. Tim Livengood, a researcher with the National Center for Earth and Space Science Education and the University of Maryland, now stationed at NASA’s Goddard Space Flight Center in Greenbelt.

Dr. Theodor Kostiuk of NASA Goddard explains further: “Although the air over the polar regions in these upper atmospheric layers on Venus was colder than the air over the equator in most measurements, occasionally it appeared to be warmer. In Earth’s atmosphere, a circulation pattern called a ‘Hadley cell’ occurs when warm air rises over the equator and flows toward the poles, where it cools and sinks. Since the atmosphere is denser closer to the surface, the descending air gets compressed and warms the upper atmosphere over Earth’s poles. We saw the opposite on Venus.”

Many factors could be contributing to Venus’ upper-atmospheric variabilities, such as interactions between opposing winds blowing around the planet at over 200 mph, giant vortexes that churn around its poles, and possibly even solar activity, like solar storms and coronal mass ejections which may create turbulence in Venus’ upper atmosphere.

“The mesosphere and thermosphere of Venus are dynamically active. Wind patterns resulting from solar heating and east to west zonal winds compete, possibly resulting in altered local temperatures and their variability over time.”

– Lead author Dr. Guido Sonnabend, University of Cologne, Germany

Artist concept of Venus' surface. (NASA)

The team also found that the temperatures of Venus’ atmosphere change over time, spanning weeks, months, years… even decades. Temperatures measured in 1990-91 are warmer than in 2009, and equatorial temperatures were even warmer in 2007.

“In addition to all these changes, we saw warmer temperatures than those predicted for this altitude by the leading accepted model,” said Kostiuk. “This tells us that we have lots of work to do updating our upper atmospheric circulation model for Venus.”

Even though Venus is compositionally similar to Earth and has a similar size as well, at some point in its history it lost all of its water to space and became the cloud-covered oven it is today. Studying Venus will help scientists learn how this may have happened and – hopefully! –  learn how to prevent the same fate from ever befalling Earth.

The paper, led by Dr. Guido Sonnabend of the University of Cologne, Germany and co-authored by Drs. Livengood and Kostiuk, appeared July 23 in the online edition of the journal Icarus.

Read more on the NASA feature article here.

Planets Party In The Morning April 28-May 1

April's Morning Conjunction Credit: Adrian West

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Set your alarm clocks for an early treat about a half an hour before sunrise on Thursday April 28 through Sunday, May 1, 2011, as there will be a planetary delight in store! Go out and with either a pair of binoculars, a small telescope, or just use your naked eyes and find an unobscured view of the Eastern horizon to see a conjunction (objects near each other in the sky) of the planets Jupiter, Mars, Venus and Mercury, below and to the left of the thin crescent moon.

Bright Venus will be easy to spot first, then Mercury followed by Jupiter. The real challenge is to find Mars which will be very close to Jupiter. See the above diagram for help on where each object is located.

If you are unlucky on the first morning, try again the following day for a chance to see this rare planetary occurrence.

While observing this close to the Sun take care and never look at the sun directly with your eyes and never through an optical instrument, as this will permanently damage your eyesight or blind you!

Only special purpose made solar telescopes and filters are safe for viewing the sun.

A Varying Venusian Vortex

Animation of Venus' southern polar vortex made from VIRTIS thermal infrared images; white is cooler clouds at higher altitudes.

Our neighboring planet Venus really is a world of extremes; searing surface temperatures, crushing air pressure, sulfuric acid clouds…Venus pretty much pushes the envelope on every aspect of rocky-planet existence. And now here’s one more thing that made scientists do a double-take: a shape-shifting vortex swirling around Venus’ south pole!

The presence of a cyclonic storm around Venus’ poles – both north and south –  has been known since Mariner 10’s pass in 1974 and then afterwards during the Pioneer Venus mission when a downwardly-spiraling formation of clouds over the planet’s north pole was imaged in infrared. It wasn’t until ESA’s Venus Express orbiter arrived in 2006 that the cyclone at the south pole was directly observed via the Visible and Infrared Thermal Imaging Spectrometer (VIRTIS) instrument…and it proved to be much stranger than anything previously expected. Continue reading “A Varying Venusian Vortex”

First-Time Solar System Mosaic From the Inside Out

MESSENGER's new solar system portrait, from the inside out

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Say cheese! The MESSENGER spacecraft has captured the first portrait of our Solar System from the inside looking out. The images, captured Nov. 3 and 16, 2010, were snapped with the Wide Angle Camera (WAC) and Narrow Angle Camera (NAC) of MESSENGER’s Mercury Dual Imaging System (MDIS).

All of the planets are visible except for Uranus and Neptune, which at distances of 3.0 and 4.4 billion kilometers were too faint to detect with even the longest camera exposure time of 10 seconds. Their positions are indicated. The dwarf-planet Pluto, smaller and farther away, would have been even more difficult to observe.

Earth’s Moon and Jupiter’s Galilean satellites (Callisto, Ganymede, Europa, and Io) can be seen in the NAC image insets. Our Solar System’s perch on a spiral arm provided a beautiful view of part of the Milky Way galaxy, bottom center.

The following is a graphic showing the positions of the planets when the graphic was acquired:

The new mosaic provides a complement to the Solar System portrait – that one from the outside looking in – taken by Voyager 1 in 1990.

These six narrow-angle color images were made from the first ever 'portrait' of the solar system taken by Voyager 1, which was more than 4 billion miles from Earth and about 32 degrees above the ecliptic. The spacecraft acquired a total of 60 frames for a mosaic of the solar system which shows six of the planets. Mercury is too close to the sun to be seen. Mars was not detectable by the Voyager cameras due to scattered sunlight in the optics, and Pluto was not included in the mosaic because of its small size and distance from the sun. These blown-up images, left to right and top to bottom are Venus, Earth, Jupiter, and Saturn, Uranus, Neptune. The background features in the images are artifacts resulting from the magnification. The images were taken through three color filters -- violet, blue and green -- and recombined to produce the color images. Jupiter and Saturn were resolved by the camera but Uranus and Neptune appear larger than they really are because of image smear due to spacecraft motion during the long (15 second) exposure times. Earth appears to be in a band of light because it coincidentally lies right in the center of the scattered light rays resulting from taking the image so close to the sun. Earth was a crescent only 0.12 pixels in size. Venus was 0.11 pixel in diameter. The planetary images were taken with the narrow-angle camera (1500 mm focal length). Credit: NASA/JPL

“Obtaining this portrait was a terrific feat by the MESSENGER team,” says Sean Solomon, MESSENGER principal investigator and a researcher at the Carnegie Institution. “This snapshot of our neighborhood also reminds us that Earth is a member of a planetary family that was formed by common processes four and a half billion years ago. Our spacecraft is soon to orbit the innermost member of the family, one that holds many new answers to how Earth-like planets are assembled and evolve.”

Source: MESSENGER

JAXA Considering Second Try at Akatsuki-Venus Rendezvous One Year Earlier than Planned

Artist’s impression of the Venus Climate Orbiter (aka. “Akatsuki”) by Akihiro Ikeshita. Image Credit: JAXA

The Japan Aerospace Exploration Agency (JAXA) is now considering making a second attempt to insert the Akatsuki probe into Venus’ orbit one year earlier than originally planned, in five years instead of six. After a malfunctioning valve in the spacecraft’s fuel pressure system caused the engine to function abnormally, Akatsuki failed to enter Venus’ orbit on Dec. 7, 2010 as planned. JAXA had said the spacecraft’s orbit around the Sun would put it in position for another orbit insertion attempt in about six years. But because the spacecraft’s speed has slowed more than expected, the agency now says it may be possible to slowly decelerate Akatsuki even more and let Venus “catch up with it,” according to a report in the Mainichi Daily News. Therefore, an attempt to enter orbit may be made sometime in 2015. A quicker return to Venus is also advantageous in terms of the lifespan of the probe and its equipment.

“At the speed the probe was moving under our first retry plan, it would probably have been impossible to make the orbital insertion,” said a JAXA official, quoted in the Japanese online news site. “We hope to explore every possibility, and make an exploration of Venus a reality.”

After the original mission failure, JAXA had calculated that Akatsuki would make 11 trips around the Sun for every 10 Venus made, putting the next closest encounter between the spacecraft and planet sometime in December 2016 or January 2017. But subsequent examination of data showed Ataksuki’s engine power had dropped by almost 60 percent, slowing the spacecraft and making it possible to make a second attempt at entering orbit a year earlier. The bad news is that the slowdown is possibly caused by a malfunction in the fuel supply system or damage to the engine nozzle. If that is the case, the prospects for restoring full function are very low.

Additionally, if the engine nozzle has been weakened, it will be difficult to decelerate the Akatsuki enough for orbital insertion when it again closes with Venus. But after consultations with engineers, JAXA is now considering trying to decelerate the craft a little bit at a time, allowing it to make eight orbits around the sun before Venus catches up with it in five years.

Source: The Daily Mainichi News

Faulty Valve Caused Akatsuki Failure at Venus

Artists concept of Japan’s Akatsuki spacecraft at Venus. Credit: JAXA

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The Japanese space agency has deduced that a faulty engine valve was the reason the Akatsuki spacecraft did not go into orbit around Venus as planned on December 6, 2010. According to the Daily Yomiuri, a malfunctioning valve in the probe’s fuel pressure system caused the engine to function abnormally. The valve is a standard component in many previous space missions, JAXA said, and it was not modified at all for Akatsuki.

Earlier, JAXA reported that Akatsuki’s engine did perform a burn to slow it down, but 152 seconds into the burn the fuel pressure dropped and the probe became unbalanced. Because the retrofiring of the rockets failed to slow down the probe enough for Venus to capture it, it was unable to enter into orbit around the planet, and then went into safe mode.

The JAXA investigation identified five possible causes of the mishap and all stemmed from the valve’s failure to open. JAXA also said they intend “to further investigate why the valve did not open, and how much damage was caused to Akatsuki’s thruster nozzle, by conducting tests that also will indicate whether the probe will be able to go into orbit around Venus when it comes near the planet six years from now.”

After Akatsuki’s launch in May, the functions of its main engine were tested in June. However, the engine was fired for too short a time to detect the problem with the valve, JAXA said.

The findings were presented to the Education, Culture, Sports, Science and Technology Ministry’s Space Activities Commission.

Source: Daily Yomiuri

Akatsuki Update: Fuel Pressure Drop Likely Caused Insertion Failure

An image showing Venus from three of Akatsuki's different instruments, taken during a functions check of the probe. From left to right: the ultraviolet imager (UVI), 1 micron camera (IR1) and long wave infrared camera (LIR). Image Credit: ISAS

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While JAXA is still trying to get an exact handle on the problems that the Akatsuki probe sent to Venus encountered, there is a little bit of news leaking out. JAXA held a press conference last night, and the Yomiuri Shimbun newspaper has a brief recap of the conference. During some of the systems checks on the probe, it also took a few images of Venus, and many of the instruments on the probe appear to be working okay – it’s the engine that’s having the most problems.

Here’s what is known so far: Akatsuki’s engine did perform a burn to slow it down, but 152 seconds into the burn the fuel pressure dropped and the probe became unbalanced. Because the retrofiring of the rockets failed to slow down the probe enough for Venus to capture it, it was unable to enter into orbit around the planet, and then went into safe mode.

As to what caused the sudden drop in fuel, JAXA currently suspects that there is a damaged pipe or valve that reduced the flow of helium into the engine, but that is still speculative. As the engine burns propellant (Akatsuki uses a hydrazine/nitrogen tetroxide engine), helium flows into the tank to maintain the pressure. Something failed in the helium injection flow, and precipitated a drop in internal tank pressure, reducing the flow of propellant and causing the engines to stop burning.

The ceramic nozzle of the engine is also thought to have been damaged by the misfiring, which may make the task of trying to get the probe to Venus when the chance comes around again in six years a daunting one.

An image of Venus taken by Akatsuki's Ultraviolet imager (UVI) at the 365 nm wavelength, the color is artificial. Field of View: 12 deg x 12 deg Image Credit: ISAS

JAXA is planning on doing some tests on the ground to maybe come to a workaround of this problem. There seems to be plenty of fuel left, which is good news, but the damaged nozzle is not. Maybe they’ll call in some Hayabusa team members, and pull it through.

The Christian Science Monitor reported yesterday that there is some speculation that something may have struck the probe, though this most recent press conference from JAXA makes no mention of it.

Also, Emily Lakdawalla at The Planetary Society Blog reprinted some tweets translated from Japanese that summarize details from the press conference, as well as the Yomiuri Shimbun article.

Source: Yomiuri Shimbun, ISAS, the Planetary Society Blog,