Posted on by Nancy Atkinson

MESSENGER Looks Back at the Earth and Moon

Earth and Moon from 114 Million Miles.Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

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A new image to add to the family photo album! The MESSENGER spacecraft is working its way to enter orbit around Mercury in March of 2011, and while wending its way, took this image of the Earth and Moon, visible in the lower left. When the image was taken in May 2010, MESSENGER was 183 million kilometers (114 million miles) away from Earth. For context, the average separation between the Earth and the Sun is about 150 million kilometers (93 million miles). It’s a thought provoking image (every one of us is in that image!), just like other Earth-Moon photos — Fraser put together a gallery of Earth-Moon images from other worlds, and this one will have to be added. But this image was taken not just for the aesthetics.

This image was taken as part of MESSENGER’s campaign to search for vulcanoids, small rocky objects hypothesized to exist in orbits between Mercury and the Sun. Though no vulcanoids have yet been detected, the MESSENGER spacecraft is in a unique position to look for smaller and fainter vulcanoids than has ever before been possible. MESSENGER’s vulcanoid searches occur near perihelion passages, when the spacecraft’s orbit brings it closest to the Sun. August 17, 2010 was another such perihelion, so if MESSENGER was successful in finding any tiny asteroids lurking close to the Sun, we may hear about it soon.

Source: MESSENGER

Posted on by Nancy Atkinson

WISE Cryostat is Depleting

An image released in August 2010 from WISE image of the Small Magellanic Cloud. Image credit: NASA/JPL-Caltech/WISE Team

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NASA’s Wide-field Infrared Survey Explorer, or WISE, is losing its cool. The spacecraft is running out of the frozen coolant needed to keep its heat-sensitive instrument chilled, and will only be in operation for 2-3 more months. While the spacecraft was designed to be rather short-lived – 7 to 10 months — it still is sad to see the mission winding down. But WISE has completed its primary mission, a full scan of the entire sky in infrared light, which was accomplished by July 17, 2010. The mission has taken more than 1.5 million snapshots so far, uncovering hundreds of millions of objects, including asteroids, stars and galaxies. It has discovered more than 29,000 new asteroids to date, more than 100 near-Earth objects and 15 comets.

The telescope has two coolant tanks that keep the spacecraft’s normal operating temperature at 12 Kelvin (minus 438 degrees Fahrenheit). The outer, secondary tank is now depleted, causing the temperature to increase. One of WISE’s infrared detectors, the longest-wavelength band most sensitive to heat, stopped producing useful data once the telescope warmed to 31 Kelvin (minus 404 degrees Fahrenheit). The primary tank still has a healthy supply of coolant, and data quality from the remaining infrared detectors remains high.

WISE is continuing a second survey of about one-half the sky as originally planned. It’s possible the remaining coolant will run out before that scan is finished. Scientists say the second scan will help identify new and nearby objects, as well as those that have changed in brightness. It could also help to confirm oddball objects picked up in the first scan.

NASA is hoping to find more Near Earth Objects with WISE’s remaining days of operations.
“WISE’s prime mission was to do an infrared background map,” said Lindley Johnson, program executive for the Near-Earth Objects Observation program at NASA, speaking at a workshop this week to define objectives for exploring asteroids. “But we realized in talking with scientists that it would also make a good asteroid detector by comparing images. It has done a good job of finding a lot of objects for us.”

Source: NASA

Posted on by Nancy Atkinson

NASA Braces Rover Fans for the Worst About Spirit

Spirit rover, as seen by HiRISE on Feb. 15, 2010. Crop and colorization by Stuart Atkinson, image credit: NASA/JPL, U of AZ

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JPL issued a press release today with an update that mission controllers have still not heard from the hibernating Spirit rover. Even though the rover is experiencing one of Mars’ harshest winters since the rovers arrived, the rover team has begun an active “paging” technique called ‘sweep and beep’ in an effort to communicate with Spirit instead of just passively listening for any activity from the rover. Based on models of Mars’ weather and its effect on available power, mission managers believe that if Spirit responds, it most likely will be in the next few months. But in a ‘hope for the best, prepare for the worst’ kind of way, the press release added, “However, there is a very distinct possibility Spirit may never respond.”

“It will be the miracle from Mars if our beloved rover phones home,” said Doug McCuistion, director of NASA’s Mars Exploration Program. “It’s never faced this type of severe condition before – this is unknown territory.”

The Martian winter runs from May through November here on Earth, so there’s still a lot of long, dark winter to get through. Spirit has not communicated since March 22, 2010 and is likely in a low-power hibernation mode since the rover was not able to get to a favorable slope for its fourth Martian winter. The low angle of sunlight during these months limits the power generated from the rover’s solar panels. During hibernation, the rover shuts down communications and other activities so available energy can be used to recharge and heat batteries, and to keep the mission clock running.

On July 26, rover engineers began the sweep and beep. “Instead of just listening, we send commands to the rover to respond back to us with a communications beep,” said John Callas, project manager for the rover. “If the rover is awake and hears us, she will send us that beep.”

The earliest date the rover could generate enough power to send a beep to Earth was calculated to be around July 23. However, mission managers don’t anticipate the batteries will charge adequately until late September to mid-October.

So, there is still a lot of time to wait things out. While I don’t think the rover team is giving up on Spirit at all, it appears they want to prepare the rover faithful for the worst.

But I’m going to make a prediction here: not only will Spirit wake up, but the rover driving team will be able to get her out of the sand trap she is stuck in. Just a hunch, but you heard it here and only time will tell if my prediction comes true.

Based on previous Martian winters, the rover team anticipates the increasing haziness in the sky over Spirit will offset longer daylight for the next two months. The amount of solar energy available to Spirit then will increase until the southern Mars summer solstice in March 2011. JPL says that if we haven’t heard from Spirit by March, 2011 it is unlikely that we will ever hear from it.

Leave it to Steve Squyres, however, principal investigator for the rovers, to leave us with a little hope: “This has been a long winter for Spirit, and a long wait for us,” he said. “Even if we never heard from Spirit again, I think her scientific legacy would be secure. But we’re hopeful we will hear from her, and we’re eager to get back to doing science with two rovers again.”

Source: JPL

Posted on by Nancy Atkinson

Ring Around Rhea? Probably Not

Rhea, taken by the Cassini spacecraft in March, 2010. Credit: NASA/JPL/Space Science Institute

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Back in 2005, a suite of six instruments on the Cassini spacecraft detected what was thought to be an extensive debris disk around Saturn’s moon Rhea, and while there was no visible evidence, researchers thought that perhaps there was a diffuse ring around the moon. This would have been the first ring ever found around a moon. New observations, however, have nixed the idea of a ring, but there’s still something around Rhea that is causing a strange, symmetrical structure in the charged-particle environment around Saturn’s second-largest moon.

Researchers announced their findings in 2008 that there was a sharp, symmetrical drop in electrons detected around Rhea. This moon is about 1,500 kilometers (950 miles) in diameter, and scientists began searching for what could have caused the drop. If there were a debris disk around Rhea, it would have had to measure several thousand miles from end to end, and would probably be made of particles that would range from the size of small pebbles to boulders.

Testing the hypothesis, Cassini flew by the moon several times and took 65 images between 2008 and 2009, flying at what would be edge-on to the rings, where the greatest amount of material would be within its line of sight.

Using light angles to their advantage — and if the ring was there – the scientists should have been able to detect micron-sized particles up to boulder size objects.

But they saw nothing.

“There are very strong and interesting and unexplained electromagnetic effects going on around Rhea,” said Matthew Tiscareno from Cornell University, who led the imaging campaign. “But we’re making a pretty strong case that it’s not because of solid material orbiting the moon….For the amount of dust that you need to account for [the earlier] observations, if it were there, we would have seen it.”

While the ring hypothesis has been disproved, there’s still a mystery about the cause of the symmetrical structure in the charged-particles around the moon.

But the Cassini spacecraft and team are up for the challenge.

Source: Cornell University

Posted on by Nancy Atkinson

Best Reality TV Ever: Camera Will Take Video of Next Mars Rover Landing

This graphic portrays the sequence of key events in August 2012 from the time the NASA's Mars Science Laboratory spacecraft, with its rover Curiosity, enters the Martian atmosphere to a moment after it touches down on the surface. Image credit: NASA/JPL-Caltech/Malin Space Science Systems

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Now THIS is what I call “must-see TV!” A camera on the next Mars Rover — MSL, also known as Curiosity – will start recording high-definition video about two minutes before the rover lands on Mars, currently scheduled for August 2012. The Mars Descent Imager, or MARDI, will provide all of us Martian-wannabes with the first-ever ride along with the landing — and this will be a very unique landing, with the “Sky –Crane” lowering Curiosity to the planet’s surface. The video won’t be live, however – that’s way too much data for the spacecraft to send back to Earth at such an important event, but we will get to see it later. JPL provided a description of what the video should look like:


This Mars Descent Imager (MARDI) camera will fly on the Curiosity rover of NASA's Mars Science Laboratory mission. Image credit: NASA/JPL-Caltech/Malin Space Science Systems

MARDI will start recording high-resolution video about two minutes before landing in August 2012. Initial frames will glimpse the heat shield falling away from beneath the rover, revealing a swath of Martian terrain below illuminated in afternoon sunlight. The first scenes will cover ground several kilometers (a few miles) across. Successive images will close in and cover a smaller area each second.

The full-color video will likely spin, then shake, as the Mars Science Laboratory mission’s parachute, then its rocket-powered backpack, slow the rover’s descent. The left-front wheel will pop into view when Curiosity extends its mobility and landing gear.

The spacecraft’s own shadow, unnoticeable at first, will grow in size and slide westward across the ground. The shadow and rover will meet at a place that, in the final moments, becomes the only patch of ground visible, about the size of a bath towel and underneath the rover.

Dust kicked up by the rocket engines during landing may swirl as the video ends and Curiosity’s surface mission can begin.

All of this, recorded at about four frames per second and close to 1,600 by 1,200 pixels per frame, will be stored safely into the Mars Descent Imager’s own flash memory during the landing. But the camera’s principal investigator, Michael Malin of Malin Space Science Systems, San Diego, and everyone else will need to be patient. Curiosity will be about 250 million kilometers (about 150 million miles) from Earth at that point. It will send images and other data to Earth via relay by one or two Mars orbiters, so the daily data volume will be limited by the amount of time the orbiters are overhead each day.

“We will get it down in stages,” said Malin. “First we’ll have thumbnails of the descent images, with only a few frames at full scale.”

Subsequent downlinks will deliver additional frames, selected based on what the thumbnail versions show. The early images will begin to fulfill this instrument’s scientific functions. “I am really looking forward to seeing this movie. We have been preparing for it a long time,” Malin said. The lower-resolution version from thumbnail images will be comparable to a YouTube video in image quality. The high-definition version will not be available until the full set of images can be transmitted to Earth, which could take weeks, or even months, sharing priority with data from other instruments.”

Read more about the MARDI camera and MSL at JPL’s website.

Posted on by Nancy Atkinson

Rosetta Meets Asteroid Lutetia

Lutetia at closest approach. Image credit: ESA 2010 MPS for OSIRIS Team MPS/UPD/LAM/IAA/RSSD/INTA/UPM/DASP/IDA

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Over the weekend, the Rosetta spacecraft flew by asteroid Lutetia, returning the first close up images of this battered, cratered body. By all accounts, the flyby was a spectacular success with Rosetta performing faultlessly. Closest approach took place at 16:10 GMT on July 10, at a distance of 3,162 km (1964 miles). The images show that Lutetia has been on the receiving end of many impacts during its 4.5 billion years of existence. As Rosetta drew close, a giant bowl-shaped depression stretching across much of the asteroid rotated into view. The images confirm that Lutetia is an elongated body, with its longest side around 130 km (80 miles).

“I think this is a very old object. Tonight we have seen a remnant of the Solar System’s creation,” said Holger Sierks, principal investigator for the spacecraft’s OSIRIS instrument, which combines a wide angle and a narrow angle camera. At closest approach, details down to a scale of 60 meters (see below) can be seen over the entire surface of Lutetia.

At a distance of 36,000 kilometers (22,369 miles) the OSIRIS Narrow Angle Camera (NAC) took this image catching the planet Saturn in the background. Image credit: ESA 2010 MPS for OSIRIS Team MPS/UPD/LAM/IAA/RSSD/INTA/UPM/DASP/IDA

Rosetta raced past the asteroid at 15 km/s completing the flyby in just a minute. But the cameras and other instruments had been working for hours and in some cases days beforehand, and will continue afterwards. Shortly after closest approach, Rosetta began transmitting data to Earth for processing, and the Rosetta team will surely release more details in the coming days and weeks.

In the meantime, enjoy this wonderful poem composed by space poet laureate Stu Atkinson.

Lutetia in the Light

For all these years you were merely
A smear of light through our telescopes
On the clearest, coldest night; a hint
Of a glint, just a few pixels wide
On even your most perfectly-framed portraits.
But now, now we see you!
Swimming out of the dark – a great
Stone shark, your star-tanned skin pitted
And pocked, scarred after aeons of drifting
Silently through the endless ocean of space.
Here on Earth our faces lit up as we saw
You clearly for the first time; eyes wide
With wonder we traced the strangely familiar
Grooves raked across your sides,
Wondering if Rosetta had doubled back to Mars
And raced past Phobos by mistake –

Then you were gone, falling back into the black,
Not to be seen by human eyes again for a thousand
Blue Moons or more. But we know you now,
We know you; you’ll never be just a speck of light again.

—Stuart Atkinson

Zoom in on a possible landslide and boulders at the highest resolution. Image credit: ESA 2010 MPS for OSIRIS Team MPS/UPD/LAM/IAA/RSSD/INTA/UPM/DASP/IDA

Sources: ESA, JPL, Rosetta Blog

Posted on by Nancy Atkinson

Watch Live Webcast of Rosetta Flyby of Asteroid Lutetia July 10

Rosetta captured this image of asteroid (21) Lutetia on July 9, 2010, at 01:00 UTC, when the spacecraft was still about two million kilometers (and 36 hours) from the asteroid. Credit: ESA 2010 MPS for OSIRIS Team

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On July 10, ESA’s Rosetta spacecraft will fly past 21 Lutetia, the largest asteroid ever visited by a satellite. After weeks of maneuvers and optical observations, Rosetta is perfectly lined up to skim by the asteroid only 3,162 km (2,000 miles) away. ESA is hosting a live webcast at 16:00 GMT on July 10. Below is an embedded feed that will go live once the webcast begins.

For more information and a complete timeline of events, check out this ESA web page.

Watch live streaming video from eurospaceagency at livestream.com

Rosetta is expected to pass Lutetia at a relative speed of 54,000 km/hr. All this takes place 454 million km from Earth. Lutetia is a major scientific target of Rosetta’s mission, so most of the orbiter and lander instruments will be on for flyby, studying the asteroid’s surface, dust environment, exosphere, magnetic field, mass and density.

Rosetta is on its way to a 2014 rendezvous with comet 67P/Churyumov-Gerasimenko.

Posted on by Nancy Atkinson

Curiosity Gets Her Wheels

She’s a rover with places to go and things to do, so one of the main components of NASA’s next Mars rover, the Mars Science Lab (named Curiosity) is wheels. Last week, the wheels and a suspension system were installed on the rover, an important step in getting ready for her mission to Mars. Launch is currently scheduled for sometime between November 25 and Decemeber 18, 2011, and Curiosity’s mission is to study its landing site for habitable environments – both ancient and current.
Continue reading “Curiosity Gets Her Wheels”

Posted on by Nancy Atkinson

Hayabusa Sample Return Canister Opened, Contains Material

Hayabusa's sample return canister was opened to reveal a small particle inside. Credit: JAXA

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The sample return canister from the Hayabusa spacecraft has been opened, and does contain a small amount of dust particles, according to the JAXA website. This is very encouraging news! However, it is not yet known if the dust is from the asteroid Itokawa, where Hayabusa briefly touched down, or if it could be from Earth — left in the container from before launch, or it possibly could have made its way in there during the landing/post landing handling. “Material on the planet or asteroid or particulate matter is at this stage is unknown, we will consider in detail,” is the Google translate version of the JAXA press release. According to Emily Lakdawalla at the Planetary Society, the dust grains are extremely small, about 0.01-millimeter in size, and there are about a dozen of them inside the container. This image was taken on June 28, 2010, and below is a magnified view of one of the particles.

Magnified view of a dust particle in the Hayabusa canister. Credit: JAXA

This magnified view was taken on June 29, and shows a magnified view of one very small particle being picked up by a quartz manipulator, which appears as a stripe on the image.
It likely will take several weeks to confirm whether the particles are from the asteroid, but if so, would be the first-ever asteroid sample return.

Below is an image of Earth that Hayabusa took as it approached the home planet.

Earth seen by the returning Hayabusa. Credit: JAXA

Sources: JAXA, The Planetary Society, BBC

Posted on by Nancy Atkinson

All-Sky Stunner from Planck

A multi-color all-sky image of the microwave sky. Credit: ESA, HFI and LFI consortia

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After a year of observations, the Planck observatory team released an all-sky microwave image, and what a gorgeous image it is! The Planck satellite looks at the entire sky in the microwave region of the electromagnetic spectrum, (30 to 857 GHz) with the main goal of tracking down the echoes of the Big Bang, the Cosmic Microwave Background (CMB.) This new image reveals the cosmic signal is literally hidden behind a fog of foreground emission, arising mostly from the interstellar medium (ISM), the diffuse mixture of gas and dust filling our Galaxy.

At the top and bottom of the image in the red and yellow marbled region is where the CMB is visible.

“By contrast, a good part of the sky is dominated by the Milky Way contribution, shining strongly along the Galactic Plane but also extending well above and below it, albeit at a very much lower intensity,” said Jan Tauber, Planck Project Scientist.

To produce this image, the Planck team combined data from the full frequency range of Planck. The main disc of our Galaxy runs across the center of the image, with streamers of cold dust reaching above and below the Milky Way. This galactic web is where new stars are being formed, and Planck has found many locations where individual stars are edging toward birth or just beginning their cycle of development.

To get your bearings of where everything is locatated, here is an annotated version.

Annotated version of the Planck all-sky image. Credit: ESA, HFI and LFI consortia.

“Planck has ‘painted’ us its first spectacular picture of the Universe,” said Dr. David Parker, Director of Space Science and Exploration for the UKSpace Agency. “This single image captures both our own cosmic backyard — the Milky Way galaxy that we live in — but also the subtle imprint of the Big Bang from which the whole Universe emerged. We’re proud to be supporting this great new discovery machine and look forward to our scientists unraveling the deeper meaning behind the beauty of this first image.”

And this is just the beginning of beautiful things from Planck!

Here’s another annotated version:

Planck all-sky annotated image. Credit: ESA, HFI and LFI consortia.

(Thanks to IVAN3MAN for suggesting to add this image.)

For more info see this ESA webpage, and the Planck website.