Mercury


This video is a compilation of thousands of images taken by the MESSENGER spacecraft of Mercury. It’s rendered in exaggerated colors to highlight different surface features. Rays emanating from a northern impact that stretch across much of the planet, and about half-way through the video, the light colored Caloris Basin, a northern ancient impact feature that filled with lava, rotates into view. Recent analysis of MESSENGER data indicates that Mercury has a solid inner core.\

Video Credits: NASA / Johns Hopkins University Applied Physics Laboratory / Carnegie Institution of Washington

Five Planets


five_planets_chartFrom now until around Feb. 20, pre-dawn stargazers will stand a good chance of seeing all five planets known to ancient astronomers simultaneously: Mercury, Venus, Saturn, Mars and Jupiter. Those planets should be visible to the naked eye, but a pair of binoculars may be necessary to pull Mercury out of the pre-dawn sky glow from the Sun.

Jupiter will rise in the evening, then Mars will come over the horizon after midnight, followed by Saturn, then Venus, and Mercury just before dawn. All five should be visible from southeast to southwest between 6:00 and 6:30 am local time.

Image Credit: NASA

This Isn’t the Moon


It’s Mercury. The MESSENGER spacecraft captured images used to make this video during a flyover of the planet’s north pole on 8 June, 2014. The images were taken once per second while the spacecraft was at altitudes ranging from 115 to 165 km, traveling at a speed of 3.7 km/s relative to the surface. The frame rate has been sped up by a factor of seven for ease of viewing. The images have resolutions ranging from 21 to 45 m/pixel.

[youtube https://www.youtube.com/watch?v=oSOv0-iWWwQ]

Video Credit: NASA / Johns Hopkins University Applied Physics Laboratory / Carnegie Institution of Washington

BTW, MESSENGER was launched ten years ago today.

A Day on Mercury


This animation shows wide-angle camera images of Mercury’™s south polar region taken by the MESSENGER spacecraft over one complete Mercury solar day (176 Earth days). This dataset enabled the illumination conditions at Mercury’™s south polar region to be quantified, producing the map seen at the end of the movie and provided as a separate image. The map is colored on the basis of the percentage of time that a given area is sunlit; areas appearing black in the map are regions of permanent shadow. The large crater near Mercury’s south pole, Chao Meng-Fu, has a diameter of 180 km.

[youtube http://youtu.be/Dozrf_S3v8E]

Video Credit: NASA

Look on the Sunny Side


sunny_sideThis view of Mercury’s horizon was taken by the MESSENGER spacecraft in orbit around the planet. It was acquired looking from the shadows toward the sunlit side of the planet.A 120-km impact crater stands out near the center. The crater has several chains of secondary craters which gouge linear tracks radially away from it. While this crater does not appear to be of recent origin (its rays have faded), its secondary crater chains are more prominent than most similar craters.

Once per week, MESSENGER captures images of Mercury’s limb, with an emphasis on imaging the southern hemisphere limb. These limb images provide information about Mercury’s shape and complement measurements of topography made by the spacecraft’s laser altimeter of Mercury’s northern hemisphere.

Image Credit: NASA

An Elliptical Crater


ellipticalcraterMost craters are more or less circular. This is Hovnatanian crater on Mercury, named for Armenian painter Hakop Hovnatanian. The crater’s elliptical shape and the bright rays’ butterfly pattern indicate the whatever hit the planet causing the crater came in at a very shallow angle. The brightness of the rays indicates that they are relatively young features on Mercury’s surface.

This image was acquired by the MESSENGER spacecraft, the first to orbit Mercury. MESSENGER has acquired over 150,000 images and other extensive data sets, and should continue orbital operations until early 2015.

Image Credit: NASA

UPDATE—Cabin Boy Bill Schmalfeldt likes this picture. He tweets:

RadioWMS ‏I don’t know about you, but I enjoy these closeup pictures of Hoge’s complexion.
3:26 PM – 3 Aug 13 GMT

Taking Mercury for a Spin


All the surface of planet Mercury has now been mapped. Detailed observations of the planet have been being made since the MESSENGER spacecraft first flew by Mercury in 2008 and entered orbit in 2011. Previously, the Mariner 10 flybys in the 1970s photographed only about half of the planet which is too far away for Earth-based telescopes to see any significant detail. This video was put together using thousands of images of Mercury. Exaggerated color enhancement provides better contrast of different surface features. A couple of interesting features to watch for as the planet rotates are sets of rays emanating from impact sites that stretch across much of the planet and the light-colored Caloris Basin, a ancient impact feature that filled with lava in the northern hemisphere.

Video Credit: NASA

Triple Conjunction


tripleconjuntion2scaleWhile driving back home from Baltimore last night, my son and I saw a rare triple conjunction of the planets Mercury, Venus, and Jupiter in the early night sky. Last night’s show was the most compact arrangement of the planets, but they will be visible together all this week. Mercury and Venus will be a bit higher above the horizon at sunset each night even as Jupiter sinks lower. The picture on the left show the three planets to scale. Venus is the brightest object in the sky other than the Sun or Moon. It’s the planet nearest to Earth and, being closer to the Sun, brightly illuminated. Jupiter is the farthest of the three, but it’s large reflecting area makes up for the distance. Tiny Mercury is closest to the Sun, but reflects the least light to us of the three.

Image Credits: NASA

A Ridge on Mercury


converted PNM fileThis isn’t a picture of the Moon. It’s the planet Mercury as seen by the Mariner 10 spacecraft almost 40 years ago. The Antoniadi Ridge, which is over 450 km long, runs down the right side of the image. The ridge cross a large crater (80 km in diameter) and in turn appears to be interrupted by an irregular depression on the crater’s floor. The ridge extends across plain to the north and south of the crater.

Mariner 10 explored Venus in February, 1974, on the way to three encounters with Mercury in March and September, 1974, and in March, 1975. The spacecraft took more than 7,000 photos of Mercury, Venus, the Earth and the Moon.

Image Credit: NASA

Mercury’s Minerals


messenger_false_colorThis false color view of Mercury was put together using images from the color base map imaging campaign during MESSENGER‘s primary mission. The colors are not what Mercury would look like to the human eye. Instead, the colors enhance the chemical, mineralogical, and physical differences between the minerals on Mercury’s surface.

Image Credit: NASA

A Solar Day on Mercury


mercury_day_oneAfter its first Mercury solar day (176 Earth days) in orbit around the planet closest to the Sun, MESSENGER has nearly completed two of its main global imaging campaigns: a monochrome map at 250 m/pixel and an eight-color, 1 km/pixel color map. There are a few small gaps which will be filled in during the next solar day. The MESSENGER maps provide uniform lighting conditions ideal for assessing Mercury’s surface features as well as the color and compositional variations across the planet. The views seen here were assembled from thousands of individual images. The color image was taken through the wide-angle camera filters at 1000, 750, and 430 nm wavelengths displayed in red, green, and blue, respectively.

Image Credit: NASA

The Closest Ice to the Sun


MercuryNorthPoleOK, Mercury isn’t a likely spot for the Winter Olympics. But new data from the Mercury orbiting MESSENGER spacecraft indicate that it has a substantial amount of water ice in permanently shadowed regions found in craters near its north pole. The idea that ice might be found on Mercury has been around for years. For many years, it was thought that one side of the planet was always pointed away from the sun and, thus, very cold. More recently, it was found that the planet slowly rotated, ending that speculation. Then, radar observations of Mercury showed bright, hence highly reflective, regions near the north pole. Those areas are marked in yellow in this map derived from MESSENGER images. The radar bright regions correspond with floors and walls of north polar impact craters. Farther from the pole the regions are mostly on the north facing crater walls. MESSENGER‘s neutron spectroscopy and thermal models for the craters indicate material in these regions has a hydrogen content consistent with nearly pure water ice and is trapped in an area with temperatures that remain below 100 K (-280 °F, -173 °C). Comet impacts are thought to be the source of the ice on Mercury.

Image Credit: NASA