Second NASA GRAIL MoonKAM Image

Second NASA GRAIL MoonKAM picture is on the ground, it worked perfectly, confirming the trajectory and pointing data!

NASA GRAIL: Flying formation - around the moon at 3,600 MPH

An artist's depiction of the NASA GRAIL twins (Ebb and Flow) in lunar orbit. 

During GRAIL's prime mission science phase, the two spacecraft will orbit the moon as high as 31 miles (51 kilometers) and as low as 10 miles (16 kilometers). 

Credit: NASA/Caltech-JPL/MIT

The act of two or more aircraft flying together in a disciplined, synchronized manner is one of the cornerstones of military aviation, as well as just about any organized air show.

But as amazing as the U.S. Navy's elite Blue Angels or the U.S. Air Force's Thunderbirds are to behold, they remain essentially landlocked, anchored if you will, to our planet and its tenuous atmosphere.

What if you could take the level of precision of these great aviators to, say, the moon?

"Our job is to ensure our two GRAIL spacecraft are flying a very, very accurate trail formation in lunar orbit," said David Lehman, GRAIL project manager at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "We need to do this so our scientists can get the data they need."

Essentially, trail formation means one aircraft (or spacecraft in this case), follows directly behind the other. Ebb and Flow, the twins of NASA's GRAIL (Gravity Recovery And Interior Laboratory) mission, are by no means the first to synch up altitude and "air" speed while zipping over the craters, mountains, hills and rills of Earth's natural satellite.

That honour goes to the crew of Apollo 10, who in May 1969 performed a dress rehearsal for the first lunar landing but as accurate as the astronauts aboard lunar module "Snoopy" and command module "Charlie Brown" were in their piloting, it is hard to imagine they could keep as exacting a position as Ebb and Flow.

"It is an apples and oranges comparison," said Lehman. "Lunar formation in Apollo was about getting a crew to the lunar surface, returning to lunar orbit and docking, so they could get back safely to Earth. For GRAIL, the formation flying is about the science, and that is why we have to make our measurements so precisely."

As the GRAIL twins fly over areas of greater and lesser gravity at 3,600 mph (5,800 kilometers per hour), surface features such as mountains and craters, and masses hidden beneath the lunar surface, can influence the distance between the two spacecraft ever so slightly.

How slight a distance change can be measured by the science instrument beaming invisible microwaves back and forth between Ebb and Flow?

How about one-tenth of one micron? Another way to put it is that the GRAIL twins can detect a change in their position down to one half of a human hair (0.000004 inches, or 0.00001 centimeters).

For those of you who are hematologists or vampires (we are not judging here), any change in separation between the two twins greater than one half of a red corpuscle will be duly noted aboard the spacecraft's memory chips for later downlinking to Earth.

Working together, Ebb and Flow will make these measurements while flying over the entirety of the lunar surface.

NASA GRAIL: Ebb and Flow Flying in Formation

Using a precision formation-flying technique, the twin GRAIL spacecraft will map the moon's gravity field.

The mission also will answer longstanding questions about Earth's moon, including the size of a possible inner core, and it should provide scientists with a better understanding of how Earth and other rocky planets in the solar system formed.

GRAIL is a part of NASA's Discovery Program.

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the GRAIL mission. The Massachusetts Institute of Technology (MIT), Cambridge, is home to the mission's principal investigator, Maria Zuber.

The GRAIL mission is part of the Discovery Program managed at NASA's Marshall Space Flight Center in Huntsville, Ala. Lockheed Martin Space Systems, Denver, built the spacecraft.

Launch management for the mission is the responsibility of NASA's Launch Services Program at the Kennedy Space Center in Florida. JPL is a division of the California Institute of Technology in Pasadena.

Image credit: NASA/JPL-Caltech

GRAIL Doing Science on This Week @ NASA - YouTube video

Ebb and Flow, NASA's Gravity Recovery And Interior Laboratory, or GRAIL spacecraft, have officially begun collecting science data as they orbit the moon.

Scientists will use the information gathered by the twin spacecraft to produce a high-resolution map of the lunar gravitational field.

That should provide unprecedented detail about the moon's internal structure and composition, and lead to a better understanding of how Earth and other rocky planets in the solar system formed.

Science activities are expected to conclude on May 29. Also, Station Science on Fire, NASA Administrator Charles Bolden joins The White House to encourage engineering students to "Stay With It", "G.E.M.S." at Stennis Space Center, an honour for the late NACA test pilot Scott Crossfield and more!

Grail Twin Probe to Study Earth’s Moon Gravity Field

Two spacecrafts are set to enter orbit around Earth's moon over the New Year's weekend, in the latest lunar mission to measure the uneven gravity field and determine what lies beneath the moon' core.

The near-identical Grail spacecraft, short for Gravity Recovery and Interior Laboratory, which skyrocketed from the Florida coast in September, have been independently traveling to their destination and will arrive 24 hours apart.

On New Year's Eve, one of the Grail probes will fire its engine to slow down so that it could be captured into orbit. This move will be repeated by the other the following day.

The chances of the probes overshooting are slim since their trajectories have been precise, engineers said. Getting struck by a cosmic ray may prevent the completion of the engine burn and they won't get boosted into the right orbit.

After it enters orbit, the spacecraft will spend the next two months flying in formation and chasing one another around the moon until they are about 35 miles above the surface with an average separation of 124 miles. However, data collection won't begin until March, astronomers said.

"Both spacecraft have performed essentially flawlessly since launch, but one can never take anything for granted in this business," said mission chief scientist Maria Zuber of the Massachusetts Institute of Technology.

During the probe's orbit, changes in the lunar gravity field will cause them to speed up or slow down, changing the distance between them. Radio signals transmitted by the spacecraft will measure the slight distance gaps, allowing researchers to map the underlying gravity field.

These information can help scientists deduce what's beneath the lunar surface and explain why the far side of the moon is more rugged than the side that faces Earth.

While many new information about the moon is expected from the probes, the possibility of sending astronauts back may not happen soon as the Constellation program was canceled last year by the government.

Officially known as Grail-A and Grail-B, the name of the probes were taken from a contest hosted by NASA several months ago to submit new names. The probes will be christened with the winning names after the second orbit insertion.

A Second Temporary Moon is A Normal Occurrence, Research Says - International Business Times

Research findings show that a second temporary moon is the norm in our planet, noting that what looked like a spent rocket stage which was seen orbiting the Earth in 2006 was in fact asteroid 2006 RH120, a natural satellite like the moon.

According to a team of astrophysicists from Cornell, the 2006 RH120, which measured just a few meters in diameter could be a second temporary moon. By 2007, it left the Earth's orbit in search of a new cosmic companion.

The team from Cornell, astrophysicists Mikael Granvik, Jeremie Vaubaillon, Robert Jedicke, said temporary satellites are a result of the gravitational pull of Earth and the Moon which pull on one another and also pull on anything else in nearby space.

According to reasearchers, among the most common objects that are pulled in by the Earth-Moon system's gravity are near Earth objects (NEOs) which are comets and asteroids that end up in orbit and eventually brought near Earth.

The scientists modeled the way our Earth-Moon system captures these NEOs to understand how often additional moons come and how long stay. Their findings show that the Earth-Moon system captures NEOs quite frequently.

"At any given time, there should be at least one natural Earth satellite of 1-meter diameter orbiting the Earth," the team said. These NEOs orbit the Earth for about ten months, enough time to make about three orbits, before leaving.

If the findings of the study are correct, then chances for a manned mission to an asteroid increase. Now astronauts won't have to go all the way out to an asteroid to learn about the Solar System's early history but they can wait for an asteroid to come near the Earth, researchers said.

NASA GRAIL: Artist's Rendition

Using a precision formation-flying technique, the twin GRAIL spacecraft will map the moon's gravity field, as depicted in this artist's rendering. 

Radio signals traveling between the two spacecraft provide scientists the exact measurements required as well as flow of information not interrupted when the spacecraft are at the lunar farside, not seen from Earth. 

The result should be the most accurate gravity map of the moon ever made.

The mission also will answer longstanding questions about Earth's moon, including the size of a possible inner core, and it should provide scientists with a better understanding of how Earth and other rocky planets in the solar system formed. GRAIL is a part of NASA's Discovery Program.

Image credit: NASA/JPL-Caltech

NASA's Gravity Recovery And Interior Laboratory (GRAIL)-B spacecraft successfully executed its first flight path correction maneuver Wednesday, Oct. 5. The rocket burn helped refine the spacecraft's trajectory as it travels from Earth to the moon and provides separation between itself and its mirror twin, GRAIL-A. The first burn for GRAIL-A occurred on Sept. 30.

"Both spacecraft are alive and with these burns, prove that they're kicking too, as expected," said David Lehman, GRAIL project manager at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "There is a lot of time and space between now and lunar orbit insertion, but everything is looking good."

GRAIL-B's rocket burn took place on Oct. 5 at 11 a.m. PDT (2 p.m. EDT). The spacecraft's main engine burned for 234 seconds and imparted a velocity change of 56.1 mph (25.1 meters per second) while expending 8.2 pounds (3.7 kilograms) of propellant.

GRAIL-A's burn on Sept. 30 also took place at 11 a.m. PDT. It lasted 127 seconds and imparted a 31.3 mph (14 meters per second) velocity change on the spacecraft while expending 4 pounds (1.87 kilograms) of propellant.

These burns are designed to begin distancing GRAIL-A and GRAIL-B's arrival times at the moon by approximately one day and to insert them onto the desired lunar approach paths.

Read more on NASA Grail Mission

ESA: Phobos and Deimos, Martian Moon Duo, in alignment

Phobos and Deimos raw (left panel) and processed images (right panel). Phobos rests in the foreground of the image with Deimos behind. Deimos was more than twice as far from the camera.

Credit: ESA/DLR/FU Berlin (G. Neukum).

For the very first time, the Martian moons Phobos and Deimos have been caught on camera together. ESA's Mars Express orbiter took these pioneering images last month. Apart from their 'wow' factor, these unique images will help the HRSC team validate and refine existing orbit models of the two moons.

The images were acquired with the Super Resolution Channel (SRC) of the High Resolution Stereo Camera (HRSC). The camera took 130 images of the moons on 5 November at 9:14 CET over period of 1.5 minutes at intervals of 1s, speeding up to 0.5-s intervals toward the end. The image resolution is 110 m/pixel for Phobos and 240 m/pixel for Deimos - Deimos was more than twice as far from the camera.

The Super Resolution Channel of the HRSC uses an additional lens, which has a very narrow field of view of just 0.5 degree, providing four times the resolution of the HRSC color stereo channel.

Phobos, the larger of the two moons, orbits closer to the Red Planet, circling it every 7 hours and 39 minutes. It travels faster relative to Mars than the Moon relative to Earth. It was 11,800 km from Mars Express when the images were taken. Deimos was 26,200 km away.

It is not often that both Martian moons are located directly in front of the camera, lined up one behind the other. The chance to image both moons together came on 5 November 2009 when the viewing geometry was especially favorable.

The plan to image both moons at once was years in the making and was made possible by the unique elliptical orbit of Mars Express, precise knowledge of the orbits of the planet, the moons and the spacecraft, as well as fortuitous viewing geometry, and perfect planning by the ESA and HRSC teams.

Exploration of Phobos: A Scientific Priority for Mars Express
In addition to producing high-resolution maps of the surface of Mars in color and in 3D, the exploration of Phobos is a scientific priority for the HRSC team. The potato-shaped, 27 × 22 × 18 km moon has already been photographed 127 times by the HRSC, improving our knowledge of the topography of the moon, and providing insight into its origins and development.

The moons of Mars still hold many mysteries. Phobos is made of dark material that does not reflect much light, and some scientists suspect it has a chemical composition similar to that of carbonaceous chondrite asteroids.

Phobos may also contain water ice, which could be an important resource for future Mars explorers. As missions like Mars Express continue to observe Phobos and Deimos, scientists hope to reveal more information about these unique satellites of Mars.