Missions Archives

May 4, 2009December 24, 2015 by Nancy Atkinson

Is a Nearby Object in Space Beaming Cosmic Rays at Earth?

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Data from several different space and ground based observatories imply the presence of a nearby object that is beaming cosmic rays our way. Scientists with the Fermi Space Telescope say an unknown pulsar may be close by, sending electrons and positrons towards Earth. Or another more exotic explanation is that the particles could come from the annihilation of dark matter. But whatever it is, the source is relatively close, surely in our galaxy. “If these particles were emitted far away, they’d have lost a lot of their energy by the time they reached us,” said Luca Baldini, a Fermi collaborator.

Comparing data from the Fermi space telescope with results from the PAMELA spacecraft and the High Energy Stereoscopic System (H.E.S.S.) ground-based telescope, the three observatories have found surprisingly more particles with energies greater than 100 billion electron volts (100 GeV) than expected based on previous experiments and traditional models.

Fermi is primarily a gamma ray detector, but its Large Area Telescope (LAT) is also tool for investigating the high-energy electrons in cosmic rays.

Video of the LAT detecting high energy particles.

Cosmic rays are hyperfast electrons, positrons, and atomic nuclei moving at nearly the speed of light. Unlike gamma rays, which travel from their sources in straight lines, cosmic rays wend their way around the galaxy. They can ricochet off of galactic gas atoms or become whipped up and redirected by magnetic fields. These events randomize the particle paths and make it difficult to tell where they originated. But determining cosmic-ray sources is one of Fermi’s key goals.

Using the LAT, which is sensitive to electrons and their antimatter counterparts, positrons, the telescope looked at the energies of 4.5 million cosmic rays that struck the detector between Aug. 4, 2008, and Jan. 31, 2009 and found more of the high-energy variety than expected, those with more than 1 billion electron volts (eV).

A spokesman from the Goddard Space Flight Center said the exact number of how many more is not currently available, due to peculiarities of the data.

But results from Fermi also refute other recent findings from a balloon-borne experiment. The Advanced Thin Ionization Calorimeter (ATIC) captured evidence for a dramatic spike in the number of cosmic rays at energies around 500 GeV from its high atmospheric location over Antarctica. But Fermi did not detect these energies.

“Fermi would have seen this sharp feature if it was really there, but it didn’t.” said Luca Latronico, a team member at the National Institute of Nuclear Physics (INFN) in Pisa, Italy. “With the LAT’s superior resolution and more than 100 times the number of electrons collected by balloon-borne experiments, we are seeing these cosmic rays with unprecedented accuracy.”

“Fermi’s next step is to look for changes in the cosmic-ray electron flux in different parts of the sky,” Latronico said. “If there is a nearby source, that search will help us unravel where to begin looking for it.”

Source: NASA

April 30, 2009December 24, 2015 by Nancy Atkinson

It’s Official: Hubble Mission to Launch May 11

[/caption]After today’s Flight Readiness Review for space shuttle Atlantis’ STS-125 mission to the Hubble Space Telescope, mission managers unanimously agreed to set May 11 at 2:01 p.m. EDT as the launch date. This long awaited flight will repair and upgrade Hubble, likely the most significant satellite ever launched. And, for the space shuttle, it’s a final visit to a dear, old friend.

During the 11-day mission’s five spacewalks, astronauts will install two new instruments, repair two inactive ones and perform the component replacements that will keep the telescope functioning into at least 2014.

In addition to the originally scheduled work, Atlantis also will carry a replacement Science Instrument Command and Data Handling Unit for Hubble. Astronauts will install the unit on the telescope, removing the one that stopped working on Sept. 27, 2008, delaying this servicing mission until the replacement was ready.

Veteran astronaut Scott Altman will command the final space shuttle mission to service NASA’s Hubble Space Telescope, and retired Navy Capt. Gregory C. Johnson will serve as pilot. Mission specialists rounding out the crew are: veteran spacewalkers John Grunsfeld and Mike Massimino, and first-time space fliers Andrew Feustel, Michael Good and Megan McArthur.

Source: NASA

April 29, 2009December 24, 2015 by Nancy Atkinson

Opportunity Finds Young Crater on Mars

A brand new bouncing baby crater. Opportunity Rover, portion of Navcam mosaic (Sol 1825; PIA 1185). Image credit: NASA/JPL-Caltech

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The two Mars Exploration Rovers have both seen their fair share of craters in their five years on Mars. Opportunity is currently booking it across Meridiani Planum on her way to Endeavour Crater, an ancient, huge hole in the ground (22 kilometers (13.7 miles across). But recently she came across the youngest crater either rover has ever seen. This crater is “young,” in relative terms; scientists say this small crater called “Resolution” formed sometime in the past 100,000 years. Most features studied by Opportunity are much older, including rocks over 3 billion years old. In contrast to these seniors, Resolution is just a baby.

Unlike a baby’s soft skin, a newborn crater starts out sharp, and only softens over time. As craters age, the “sandblasting” action of the Martian wind erodes rocks ejected during crater formation and fills its bowl with sand. Signs of this crater’s youth are fresh rocks on the crater rim and an empty bowl. The newer crater also drapes over older surrounding dunes. Finding youth pays off: scientists can compare Resolution to older craters to learn how fast wind changes the Martian surface over time.

Von Braun hill on Mars. Credit: NASA/JPL

In other rover news, Spirit has received a boost of power from a wind cleaning event. Rover driver Scott Maxwell shared via Twitter that Spirit’s current energy output is up to 371 watts/hour per sol. This is up from less than 250watts/hour in January. Maxwell said Spirit’s solar panels are the cleanest they’ve been in 550 sols. That’s good news, because Spirit needs all the energy she can get, with trying to battle some recent issues with memory problems.

The image above is Spirit’s current view, with a mound in the upper left called “Von Braun” that is the rover’s possible investigation site in future months. From the location where Spirit was when the image was taken, Von Braun is about 160 meters (525 feet) away.

Source: JPL

April 28, 2009April 26, 2016 by Nancy Atkinson

Mars Rovers Are “Good Old Girls”

Our beloved Mars Exploration Rovers, Spirit and Opportunity have seemingly touched us all with their amazing discoveries and their apparently quite different and quirky personalities, but most of all with their durability and resilience. They’ve survived through two rough Martian winters and a couple of nasty dust storms, not to mention persevering through everything the JPL scientists and engineers have asked them to do (climbing hills, descending into craters, for example) and putting on more mileage than anyone ever thought possible. To honor the rovers and to commemorate their five years on Mars, one of my fellow Solar System Ambassadors, Steve Hammond, has created a video of highlights from the rovers, set to music by the very talented Marion Call with her song “Good Old Girl.” Steve says in his blog, Ridiculous Thoughts, that the topic he gets the most request for as a Solar System Ambassador is Mars, and particularly the rovers. “Public interest hasn’t waned. It seems that everybody I talk to knows Spirit and Opportunity by name, and at least some highlights of their mission. People genuinely care about these little robots.” Thanks to Steve for sharing the video. Enjoy!
Continue reading “Mars Rovers Are “Good Old Girls””

April 28, 2009December 24, 2015 by Nancy Atkinson

Herschel and Planck Set to Launch on May 14

The Herschel and Planck spacecraft. Credit: ESA

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The European Space Agency announced today that the Herschel and Planck spacecraft will now launch on May 14. Liftoff had been delayed to allow time for additional checks on the Ariane 5 ECA launch vehicle. The two spacecraft are launching together in what was originally a cost saving move, but the complexity of preparing two spacecraft at once has caused frequent delays and cost overruns. However, now that the launch is near, hopefully the cutting-edge technologies included in both spacecraft will soon pay off in new discoveries astronomy and cosmology.

The Herschel Space Observatory’s primary mirror is the largest single mirror ever built for a space telescope. At 3.5-meters in diameter the mirror will collect long-wavelength radiation from some of the coldest and most distant objects in the Universe. The mirror is also a technological wonder: it uses 12 silicon carbide petals fused together into a single piece. Herschel will be the only space observatory to cover a spectral range from the far infrared to sub-millimeter.

Launch configuration for the Herschel and Planck spacecraft. Credit: ESA

Planck is designed to image the anisotropies of the Cosmic Background Radiation Field over the whole sky, with unprecedented sensitivity and angular resolution. It will provide a major source of information relevant to several cosmological and astrophysical issues, such as testing theories of the early universe and the origin of cosmic structure.

The two satellites are being prepared for launch and recently were both fueled with hydrazine. Planck’s three-stage active cryogenic cooler, needed to keep the instruments at extremely cold temperatures, has been filled with helium-3 and helium-4. Herschel’s cryogenic tanks are also being filled with superfluid helium.
Herschel and Planck will liftoff from Europe’s Spaceport in Kourou, French Guiana

Source: ESA

April 24, 2009December 24, 2015 by Nancy Atkinson

Mars Express Spies Rocky, Chaotic Terrain on Mars

Ariadnes Colles that lies at about 34° south and 172° east. The ground resolution is about 13 m/pixel. Credits: ESA/ DLR/ FU Berlin (G. Neukum) Click for larger version

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Wow – what a shot by Mars Express! Mars has several regions of what is called ‘chaotic terrain’. These are areas with large accumulations of rocks of varying sizes, as well as flat-topped features. These erratically shaped rocks are large, too: between 1-10 km in size. Some chaotic terrain on Mars is thought to form when there is a sudden removal of subsurface water or ice, causing the surface material to slump and break into blocks. The region shown here, however — Ariadnes Colles — is not a water-source region, so scientists are still debating whether Ariadnes Colles was formed by the action of water or wind. Either way, this is a very interesting region. See below for a straight on view that’s just as incredible.

This image by the Mars Express High Resolution Stereo Camera, shows the region of Ariadnes Colles on the Red Planet. Credits: ESA/ DLR/ FU Berlin (G. Neukum) Click for larger version

A large impact crater, 1200 m deep, is visible on the right, which has a smaller crater inside of it. The larger crater is about 30 km in diameter and covers an area roughly the size of Hamburg, Germany. The smaller younger crater lies almost at the center of the older one, and has a diameter of just 10 km.

Interestingly, the blocks, or mesas have a striking lineation, as almost all are oriented in the northwest-southeast direction. By looking at the larger versions, it’s possible to see the northwestern flanks have been eroded more strongly than the opposing southeastern ones.

Some slopes of the flat-topped mesas have been covered by darker material, likely sand or volcanic ash that was blown up on the slopes.

Anyone ready to visit this interesting region?

Source: ESA

April 20, 2009December 24, 2015 by Nancy Atkinson

More Troubles for Spirit Rover

NASA's Mars Exploration Rover Spirit drove 6.98 meters (22.9 feet) southeastward on the 1,871st Martian day, or sol, of the rover's mission on Mars (April 8, 2009). As usual since losing the use of its right-front wheel in 2006, Spirit drove backward, dragging the immobile wheel. Image credit: NASA/JPL-Caltech. Full image and caption

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Poor Spirit. She’s getting old, arthritic and forgetful. The “oldest” of the two Mars Exploration Rovers had another bout of what engineers from JPL are calling “amnesia.” About a week ago, she experienced some unexpected reboots of her computer. Then, she had three good days in a row, completing Earth-commanded activities without incident. But then on April 17 and 18, she became forgetful – she failed to record data into her flash memory (where information is preserved when Spirit is powered down) and rebooted herself again. The last reboot put Spirit into autonomous operation in which the rover keeps itself healthy, and engineers are running diagnostics to try to regain control of the rover.

“We are proceeding cautiously, but we are encouraged by knowing that Spirit is stable in terms of power and thermal conditions and has been responding to all communication sessions for more than a week now,” said JPL’s Sharon Laubach, chief of the rover sequencing team, which develops and checks each day’s set of commands.

Engineers operating Spirit are investigating the reboots, and trying to determine if the amnesia events are related to the reboots. Spirit has had three of these amnesia events in the past 10 days, plus one on Jan. 25. No causal link has been determined between the amnesia events and the reboots.

Engineers have found ways to cope with various symptoms of aging on both rovers. The current diagnostic efforts with Spirit are aimed at either recovering undiminished use of the rover or, if some capabilities have been diminished, to determine the best way to keep using the rover.

Spirit driving off into the sunset, a special effects image. credit: NASA/JPL-Caltech/Cornell

Laubach said, “For example, if we do determine that we can no longer use the flash memory reliably, we could design operations around using the random-access memory.” Spirit has 128 megabytes of random-access memory, or RAM, which can store data as long as the rover is kept awake before its next downlink communications session.

During the past week of diagnostic activities, the rover has successfully moved its high-gain dish antenna and its camera mast, part of checking whether any mechanical issues with those components may be related to the reboots, the amnesia events, or the failure to wake up for three consecutive communication sessions two weeks ago.

Spirit and her twin, Opportunity, have been on Mars since 2004. Spirit’s right front wheel is stuck, and so she now drives backwards and drags the crippled wheel behind. The top image shows how the wheel is dragged through the Martian regolith.

Source: JPL

April 17, 2009December 24, 2015 by Nancy Atkinson

The STS-400 Shuttle Rescue Mission Scenario

Space shuttle Atlantis (left) and Endeavour stand on Launch Pads 39A and 39B at NASA's Kennedy Space Center in Florida. This is likely the last time this will happen. Image Credit: NASA

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Two space shuttles now sit out on the launch pads at Kennedy Space Center: Atlantis on 39A for the much anticipated Hubble Repair mission, scheduled to launch on May 12. Over on 39B sits Endeavour, which made the slow journey there early on Friday and she is now poised for the STS-400 LON (Launch On Need) Mission, a mission no one hopes will happen. This would be a mission to rescue the crew of Atlantis should the shuttle be struck by debris – either during launch or during the mission (read more about the risks of debris hit during the Hubble Mission). If STS-400 were necessary what would actually happen?

In the situation where Atlantis and the crew are not in immediate danger, but, for example, the shuttle’s thermal protection system (heat tiles) were compromised from debris hit (from insulating foam from the external tank like Columbia was, or space debris) and the shuttle would be unable to land safely, Endeavour would be launched at a specific time and inclination in order be able to rendezvous with Atlantis. The rescue flight would last 8 days and go as follows:

Once Endeavour and her four-person crew reaches orbit, the preparations for rendezvous with Atlantis would begin. Unlike all previous post-Return to Flight missions, the crew would not perform the standard Thermal Protection System inspection on Flight Day Two, but instead by done after the STS-125 crew was rescued.

Rendezvous of the two shuttles. Credit: NASA, via NASA Spaceflight.com

Endeavour would rendezvous with Atlantis the day after launching from the Kennedy Space Center. The two space shuttles would then approach each other payload bay to payload bay, at a 90-degree angle, about 44 ft apart. Endeavour’s robotic arm would grapple the orbital boom system on Atlantis. After Endeavour successfully grapples Atlantis, Endeavour would take attitude control of the “stack” of the two shuttles.

Then, comes the most interesting – and dangerous – part. Spacewalkers from Endeavour would do one space walk on Flight Day 3 to string a tether between both shuttles. On Flight Day 4, they would conduct two spacewalks to retrieve their colleagues from Atlantis.

Once Atlantis’ crew is safely aboard the rescue orbiter, Endeavour’s crew will maneuver the two vehicles to provide the right separation, which would occur during daylight so the crew could watch for any problems.

Atlantis would be released and be commanded from the ground to do deorbit and landing maneuvers and likely crash into the Pacific Ocean.

Seating on the rescue flight return. Credit: NASA, via NASA Spaceflight.com

On Flight Day 5 the dual crew would inspect Endeavour for damage, and if all was well, land on Flight Day 8.

Astronaut John Grunsfeld, one of the four spacewalkers who will fly on Atlantis, says keeping the Hubble telescope flying is a mission worth the risk.

“When you think about risk, it is all relative to what is the reward, and I think in the big picture Hubble is something that I certainly feel is worth risking my life for because it is about something that is so much bigger than all of us,” Grunsfeld said. “It is about science, it is about inspiration, it is about discovery. It is about all the kids who will look at the Hubble images and dream.”

Source: NASA Spaceflight.com

Link to larger top image

April 16, 2009December 24, 2015 by Nancy Atkinson

Dust Storms Picking Up on Mars

This nearly global mosaic from NASA's Mars Reconnaissance Orbiter on April 2, 2009, shows billowing clouds of dust being lifted into the atmosphere by a storm near the edge of the seasonal polar cap of southern Mars. Image credit: NASA/JPL-Caltech/MSSS

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Just like hurricane season or tornado season on Earth, Mars has stormy seasons, too. However, the Red Planet has dust storms, and they can be whoppers, which is bad news for the two Mars rovers, Spirit and Opportunity who rely on clear skies and sunshine for power. On April 21, Mars will be at the closest point to the sun in the planet’s 23-month, elliptical orbit. One month later, the planet’s equinox will mark the start of summer in Mars’ southern hemisphere. This atmospheric-warming combination makes the coming weeks the most likely time of the Martian year for dust storms, and given the current forecast based on data from the orbiting Mars Reconnaissance Orbiter and Mars Odyssey, these storms could be severe enough to minimize activities of the rovers.

There are several instruments on the orbiters that can monitor the weather patterns on Mars. The Mars Color Imager camera on Mars Reconnaissance Orbiter sees the entire planet every day at resolution comparable to weather satellites around Earth. Two other instruments — the Thermal Emission Imaging System on Mars Odyssey and the Mars Climate Sounder on Mars Reconnaissance Orbiter — monitor changes in airborne dust or dust-related temperatures in Mars’ upper atmosphere.

According to an article by Emily Lakdawalla at the Planetary Blog, the Climate Sounder is seeing temperatures in Mars southern hemisphere warm up rather dramatically, and even staying warmer than usual during the night. So far, however, the warming is staying south of the equator region where the rovers are.

Mars Climate Sounder profiles of Mars' atmospheric temperature, April 7, 2009 Since March 30, the dust has remained confined to the southern hemisphere. It has spread all the way to the pole and to ~20 degrees south. It is now fairly uniform in longitude, except at the northern extent of the heating. The dust is now planet encircling. In the north, the dynamical heating is now at all longitudes, but does show some preference for the meridian and 180 degree regions. It is not as warm as at the peak. There is some indication that there is a high (probably thin) haze of dust in the northern hemisphere since the middle of the previous week. Credit: NASA / JPL-Caltech

The air has been relatively clear for several months on Mars, but in March increased haze reduced Spirit’s daily energy supply by about 20 percent and Opportunity’s by about 30 percent. Widespread haze resulted from a regional storm that made skies far south of the rovers very dusty. Conditions at the rovers’ sites remained much milder than the worst they have endured. In July 2007, nearly one Martian year ago, airborne dust blocked more than 99 percent of the direct sunlight at each rover’s site.

To supplement the orbiting assets looking down on Mars and the rovers, Spirit and Opportunity point cameras toward the sun to check the clarity of the atmosphere virtually every day. These measurements let the planning team estimate how much energy the rovers will have available on the following day.

“We can identify where dust is rising into the atmosphere and where it is moving from day to day,” said Michael Malin of Malin Space Science Systems, San Diego, principal investigator for Mars Color Imager. “Our historical baseline of observing Martian weather, including data from the Mars Global Surveyor mission from 1998 to 2007, helps us know what to expect. Weather on Mars is more repetitive from year to year than weather on Earth. Global dust events do not occur every Mars year, but if they do occur, they are at this time of year.”

Winds that can lift dust into the air can also blow dust off the rovers’ solar panels. Opportunity just benefited from a blast of wind the first week of April and Spirit got to minor cleanings in February. “We’re all hoping we’ll get another good cleaning,” said rover chief engineer Bill Nelson from JPL.

Unexplained computer reboots by Spirit in the past week are not related to dust’s effects on the rover’s power supply, but the dust-storm season remains a concern. Spirit received commands Tuesday to transmit more engineering data in coming days to aid in diagnosis of the reboots.

Well keep an eye on the spacecraft keeping an eye on Mars and provide updates during dust storm season on Mars.

Sources: JPL, Planetary Blog

April 16, 2009December 24, 2015 by Nancy Atkinson

Kepler’s “First Light” Images

This image zooms into a small portion of Kepler's full field of view -- an expansive, 100-square-degree patch of sky in our Milky Way galaxy. Credit: NASA/JPL -Caltech

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W00t! Kepler has seen first light! The spacecraft has taken its first images of the star-rich sky where it will soon begin hunting for planets like Earth. These first images show the mission’s target patch of sky, a vast starry field in the Cygnus-Lyra region of our Milky Way galaxy. One image shows millions of stars in Kepler’s full field of view, while two others zoom in on portions of the larger region. “Kepler’s first glimpse of the sky is awe-inspiring,” said Lia LaPiana, Kepler’s program executive at NASA Headquarters in Washington. “To be able to see millions of stars in a single snapshot is simply breathtaking.”

The image above zooms into a small portion — just 0.2 percent –of Kepler’s full field of view, and shows an an expansive, 100-square-degree patch of sky in our Milky Way galaxy, and a cluster of stars located about 13,000 light-years from Earth, called NGC 6791, can be seen in the upper right corner. These images were taken on April 8, 2009, one day after Kepler’s dust cover was jettisoned. See more below.

Kepler main field of view. Credit: NASA/JPL - Caltech

This image shows Kepler’s entire field of view — a 100-square-degree portion of the sky, equivalent to two side-by-side dips of the Big Dipper. The regions contain an estimated 14 million stars, more than 100,000 of which were selected as ideal candidates for planet hunting. “It’s thrilling to see this treasure trove of stars,” said William Borucki, science principal investigator for Kepler at NASA’s Ames Research Center at Moffett Field, Calif. “We expect to find hundreds of planets circling those stars, and for the first time, we can look for Earth-size planets in the habitable zones around other stars like the sun.”

Kepler will spend the next three-and-a-half years searching more than 100,000 pre-selected stars for signs of planets. It is expected to find a variety of worlds, from large, gaseous ones, to rocky ones as small as Earth. The mission is the first with the ability to find planets like ours — small, rocky planets orbiting sun-like stars in the habitable zone, where temperatures are right for possible lakes and oceans of water.

This image zooms in on a region containing a star, called Tres-2, with a known Jupiter-like planet orbiting every 2.5 days.

To find the planets, Kepler will stare at one large expanse of sky for the duration of its lifetime, looking for periodic dips in starlight that occur as planets circle in front of their stars and partially block the light. Its 95-megapixel camera, the largest ever launched into space, can detect tiny changes in a star’s brightness of only 20 parts per million. Images from the camera are intentionally blurred to minimize the number of bright stars that saturate the detectors. While some of the slightly saturated stars are candidates for planet searches, heavily saturated stars are not.

“Everything about Kepler has been optimized to find Earth-size planets,” said James Fanson, Kepler’s project manager at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “Our images are road maps that will allow us, in a few years, to point to a star and say a world like ours is there.”

Scientists and engineers will spend the next few weeks calibrating Kepler’s science instrument, the photometer, and adjusting the telescope’s alignment to achieve the best focus. Once these steps are complete, the planet hunt will begin.

“We’ve spent years designing this mission, so actually being able to see through its eyes is tremendously exciting,” said Eric Bachtell, the lead Kepler systems engineer at Ball Aerospace & Technology Corp. in Boulder, Colo. Bachtell has been working on the design, development and testing of Kepler for nine years.

Source: NASA