The MESSENGER spacecraft in orbit around the planet Mercury has been lowering its altitude slowly and as it gets closer to the surface of the planet it stands to reason the pictures should show more detail.
Judging from this image that is exactly what is happening. As MESSENGER enters its last year, the observations will become much more detailed. On 30 April the spacecraft altitide was 199 km (127 miles) and MESSENGER is supposed to get even lower, by about half. There is a orbit-correction manuever set for 17 June.
Those white spots along the crater rim are not washed out areas, they are hallows, depressions with bright centers. Apparently they only occur or are only noticed to occur on the sunlit areas.
“We are cutting through Mercury’s magnetic field in a different geometry, and that has shed new light on the energetic electron population,” said MESSENGER Project Scientist Ralph McNutt, of the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Md. “In addition, we are now spending more time closer to the planet in general — and that has, in turn, increased the opportunities for all of the remote sensing instruments to make higher-resolution observations of the planet.”
MESSENGER has been completing three orbits of Mercury every day since April 2012, when two orbit-correction maneuvers reduced its orbital period about Mercury from 12 hours to 8 hours. The shorter orbit has allowed the science team to explore new questions about Mercury’s composition, geological evolution, and environment that were raised by discoveries made during the first year of orbital operations.
APL’s Carolyn Ernst, the deputy instrument scientist for the Mercury Laser Altimeter (MLA), said the change from a 12- to an 8-hour orbit provided her team with 50% more altimetry tracks. “MLA coverage takes a long time to build up, and because of the small footprint of the laser, a lot of coverage is needed to obtain good spatial resolution. The more data we acquire, the better we resolve the topography of the planet,” she said. “The 8-hour orbit has also allowed us to make more MLA reflectivity measurements, which have provided critical clues for characterizing Mercury’s radar-bright deposits at high northern latitudes.”
The MESSENGER spacecraft is still going strong around Mercury the closest planet to the Sun. Considering the environment this spacecraft is doing spectacular work.
This is Mena crater, nice resolution too as this crater is 15 km (9 mi) across. I keep thinking “wings” coming out of the crater. Check the links in the image caption below to put things in perspective.
Here we get a closer look at the fresh, bright-rayed crater Mena. Solidified impact melt forms a smooth pond on the western side of the crater floor. This asymmetry is due to the fact that Mena formed on the sloping rim of an older crater, as seen in this wider view.
This image was acquired as a targeted set of stereo images. Targeted stereo observations are acquired at resolutions much higher than that of the 200-meter/pixel stereo base map. These targets acquired with the NAC enable the detailed topography of Mercury’s surface to be determined for a local area of interest.
The MESSENGER spacecraft continues to send back images from the planet Mercury. One of the more than 150,000 images so far gives us this spectacular look at Nureyev Crater on Mercury.
Nureyev is 16 km / 10 miles in diameter. Usually seeing shades of gray I find the colors are interesting, explained by the MESSENGER website:
The bright, rayed crater Nureyev is at center stage in this dramatic view toward Mercury’s eastern limb. The crater’s namesake is the Soviet/British ballet dancer Rudolf Nureyev, who died in 1993. This set of color images was obtained at a relatively small phase angle and consequently is dominated by variations in the inherent reflectance and color of the surface.
The “inherent reflectance” is pretty easy to believe since it is about nine times brighter on Mercury than it is here.
If you want to see the full-sized image check out the MESSENGER page.
Yesterday we had a look at Earth from the Cassini spacecraft which is in the Saturn system. Today we get a look from the MESSENGER spacecraft which is orbiting around Mercury.
The MESSENGER spacecraft was actually doing a survey looking for moons. You would at first think if Mercury had a moon it should be easy to spot. Not so! Mercury is so elusive owing to it being so close to the sun. The only time we get to see Mercury is when it is reaches eastern or western elogation, the point at which it is either east or west of the Sun from our perspective. When at elongation it is either leading or lagging the Sun so it becomes visible before sun rise or after sun set for a short time.
If you have a good look at the eastern horizon Mercury will in fact be at western elongation on July 30, so you should be able to see it just before sunrise. Be VERY careful not to include the Sun in your sights accidently!
No doubt some of you are going to notice the “Earth” has a bit of a tear-drop shape, this is from over exposure and the way a chip handles the light. You’ve heard me say planetary photography is very difficult, for me, this is why.
so here is part of the MESSENGER caption and if you would like to see a larger version of the image pay the MESSENGER site a visit — go ahead, it’s worth the click.
The pair of bright star-like features in the upper panel are not stars at all, but the Earth and Moon! MESSENGER was at a distance of 98 million kilometers (61 million miles) from Earth when this picture was taken. The computer-generated image in the lower left shows how the Earth appeared from Mercury at the time. Much of the Americas, all of Europe and Africa, the Middle East, and much of Asia were visible.
MESSENGER took this image as part of a campaign to search for natural satellites of Mercury. Mercury has no moons that we know of. If any exist, they must be small (less than a few kilometers), or we would have seen them by now. The strategy for the satellite search involves taking multiple images of locations at predetermined distances from Mercury, from 2.5 to 25 times the planet radius. Pictures of these points in space are captured at intervals ranging from seconds to nearly an hour, depending on their distances from Mercury. A moving satellite will appear at different positions in images of the same region of space taken at different times.
The Earth and Moon appear very large in this picture because they are overexposed. When looking for potentially dim satellites, long exposures are required to capture as much light as possible. Consequently, bright objects in the field of view become saturated and appear artificially large. In fact, the Earth and Moon are each less than a pixel in size, and no details on either can be seen. The “tails” pointing downward from the Earth and Moon are artifacts caused by the image saturation. These can be seen clearly in the zoomed image in the center lower panel.
The rover Curiosity just passed the one kilometer driving mark, that’s 0.62 miles for us metrically challanged Americans.
This image was obtained with the left front Hazard-Avoidance Camera or Hazcam just after the odometer clicked over. The date this all transpired was July 16, 2013.
The direction you are looking at is southwest, generally in the direction of an area if interest and destination of Mount Sharp about 8 km distant (~5 miles). Hope they can get pictures of some of those rocks, I’m “curious” about what they are, it appears there appears to be a couple different varieties there. I wish I knew more about geologly.
I will give more of an update this weekend. I wanted to put this up because I just switched my desktop background. If you would like one go on over to the webpage with the image to download a version for yourself.
Here’s looking at you!
Now there is a couple of other things going on we have TWO space probes about to take pictures of good old Earth.
One is the Cassini, if you lean to the geeky side like I do, you will want to run outside and wave between 5:27 and 5:42 pm EDT / 21:27 and 21:42 UTC. Be sure to be looking at the camera and smile. Just go out face due south if you are in the Northern Hemisphere, I think the opposite in you are in the Southen Hemisphere. Ok once you face South, you could take a slight turn to the East and SMILE!! LOL. Hey I’m going to do it.
The Messenger spacecraft around Mercury is also going to be taking a picture of us on July 19 and 20. The times of these images will be: 7:49 a.m., 8:38 a.m. and 9:41 a.m. EDT, or 11:49, 12:38, and 13:41 UTC. We should be able to see Europe, Middle East and Central Asia as these will be illuminated in the images.
Here’s an image of Degas crater on the planet Mercury. The RGB -Red, Green, Blue- image was obtained with the Wide Angle Camera portion of the MESSENGER spacecraft dual imaging system.
Degas is 32 miles (~52k) in diameter. It’s a little unclear what exactly the dark material on the crater floor is, it’s just called “low reflective material”. The crater floor has cracks not uncommon on Mercury. The cracks form when impact melt solidifies and contracts on cooling. Make me wonder if the cracking might be in part to the timing of the impact too as the dark side of Mercury is exceeding cold while the day side is well over 600oF / 315oC while the night side plunges to around -280oF /-173oC. The crater walls seem to be “slumping” as well.
Check out the detail on this crater called Cunningham on the planet Mercury. The image was of course taken by the MESSENGER spacecraft.
By the way, the MESSENGER spacecraft recently completed its 2,000th orbit of Mercury. Talk about resilient, this spacecraft goes from the blazing sunny side of the planet which is over 600oF (300oC) to the frigid dark side which is in the vicinity of –300oF (–185oC).
From May 6 to May 14, MESSENGER traversed a superior solar conjunction, during which the spacecraft was on the far side of the Sun from Earth. Scientists used the opportunity to measure the characteristics of the solar magnetic field from the Faraday rotation of its radio-frequency carrier.
“We found the orientation of the magnetic field within a coronal mass ejection (CME) that crossed the line of sight on May 10,” says Elizabeth Jensen, of the Planetary Science Institute in Tucson, Arizona. “We saw the rotation of the plane of polarization of MESSENGER’s radio-frequency signal as it moved deeper into the corona, giving information on the Sun’s magnetic field configuration on May 11; and on May 12, we saw magnetohydrodynamic waves, a very important mode of energy transfer in the corona.”
The resolution of this image is 30 meters/pixel and you might notice the crater features seem to look different than similar craters you’ve seen on our moon. If you did, good job, you would be correct. Mercury has more mass than the moon and gravity plays its part so the features are a bit muted in comparison.
Mercury is kind of an odd place too, one Mercury day last’s about two Mercury years. Mercury has the smallest tilt of any planet and it is the most eccentric of all the planets (no pun intended). what does that mean? Simply put it means that it travels further away from the Sun at one end of its orbit than the other – think of it as off-center in its orbit and MORE so than any of the other planets, which are all a little “off-center”.