Mars has close brush with Neptune tonight

Binocular view (~5 field) of Mars, Neptune and nearby stars this evening. The planets will be very close together – only one-fifth of a full moon diameter apart. Mars is bright, but Neptune will look like a faint star to the planet’s upper right. Stars shown to magnitude +8.5. Source: Stellarium

Mars has been hiding away in Aquarius low in the southwestern sky at dusk minding its own business. But tonight however the Red Planet will pass VERY close to another more distant planet, Neptune.

To find Mars you’ll need an open view to the southwest. This map shows the sky facing southwest at the end of evening twilight. Mars is about 12-15° above the horizon at that time. Diphda is a fairly bright star in the constellation Cetus the Sea Monster. Source: Stellarium

You can see the “double planet” faintly in 10×50 or larger binoculars but a small telescope will make it a snap. The chart shows a binocular view just the way you’d see the scene facing southwest at nightfall with north toward the upper right. The best time to view the conjunction will be at the end of twilight when they’re highest.

Track of Mars in the next few days as it glides by the planet Neptune. This is also a 5° field of view similar to what you’d see in a pair of binoculars. Created with Chris Marriott’s SkyMap software

Also in your binocular view you’ll see the stars Sigma and 58 Aquarii. Neptune will look exactly like a star and surprisingly close to Mars.

NASA to ESA: We found your dog!

NASA’s HiRise camera on the Mars Reconnaissance Orbiter detected the glint (top) of the Beagle 2 in photos taken last year and released this week. The lander appears to have at least partially deployed. Credit: NASA

Ruff-ruff! The long-lost Beagle 2 lander has been found. Wish I could say it’s still wagging its tail, but at least we finally know where it is after 11 years of wondering.

Built by the Brits and sent to the Red Planet aboard the European Space Agency’s Mars Express spacecraft in June 2003, it was set to land on Christmas Day that year. Everything worked flawlessly, with the first radio contact expected shortly after the scheduled landing time, but no signal was received. Then or ever.

The Beagle 2 lander, named after HMS Beagle, the ship that carried Charles Darwin on expeditions around the world, looks something like a pocket watch before deployment. Upon landing, the watch top (right) snapped open and the individual panels unfolded from the bottom of the lander. Credit: ESA

Beagle was the first British and European attempt to soft land on Mars. All attempts to contact the probe failed, leading some to believe that the Beagle 2 had crash landed. Later, it was determined that an error had prevented two of the spacecraft’s four solar panels from deploying, blocking the spacecraft’s ability to communicate.

Michael Croon of Trier, Germany, a former member of the European Space Agency’s Mars Express operations team pored over images taken by NASA’s Mars Reconnaissance Orbiter (MRO), which operates a high-resolution camera capable of seeing objects the size of a kitchen table on Mars, and found evidence for the Beagle 2.


This photo shows where features seen in a 2014 observation by NASA’s Mars Reconnaissance Orbiter have been interpreted as hardware from the Dec. 25, 2003, arrival at Mars of the United Kingdom’s Beagle 2 Lander. The scale bar at right shows 0.1 km or a distance of 328 feet. Click to enlarge.

NASA then directed MRO to re-photograph the expected landing location in Isidis Planitia, a large, ancient impact basin near the Martian equator. Analysis of those images revealed a bright object that appeared in multiple pictures taken at different times, ruling out the possibility it was a cosmic ray hit on the camera’s sensor. Cosmic rays, high-speed particles (mostly single protons) careen through space all the time. When they hit a camera sensor they can leave bright streaks or spots.

Two images taken months apart, with the sun at different angles, are merged in this view. A glint comes from a different part of the lander in one than in the other, interpreted as evidence of more than one deployed panel on the lander. Credit: HiRISE/NASA/JPL/Parker/Leicester

Due to the small size of Beagle 2 (less than 7 feet, or 2 meters across for the deployed lander) it’s right at the limit of detection of HiRISE, but enhanced photos clearly show what appear to be the solar panels. That means the lander made it safely to surface after all and even partially deployed.

It’s a shame we weren’t able to establish communications. Beagle 2 was equipped with a pair of stereo cameras, a microscope and a drill to collect rock samples that could be analyzed on site.

Simulation of Beagle 2 on Mars showing the instrument-studded robotic arm and the “mole” (at left). Credit: NASA

It even carried a small “mole” or Planetary Undersurface Tool (PLUTO) that could move across the surface at just under an inch per second. When a suitable spot was found, the mole would have burrowed into the ground to collect a sample. Finished with its task, the mole and its sample would have been reeled back to the lander on its power cable. Gods, what a cool idea!

“I can imagine the sense of closure that the Beagle 2 team must feel,” said Richard Zurek of JPL, project scientist now for Mars Reconnaissance Orbiter (MRO).

Even if our best plans go awry, there’s nothing like closure to help us move on to the next opportunity.

Mars gets a new crater, smiles for the camera

This new crater excavated by an impacting meteorite on Mars shows a striking pattern of ejecta – rocks and other debris blasted off the surface during the impact. The shape of the ejecta indicate that the incoming space rock likely struck from the west (left). Credit: NASA/JPL/Univ. of Arizona

Close your eyes. OK, now open them again. In a cosmic blink of the eye, this brand new crater appeared on the Martian plain called Elysium. It formed sometime between February 2012 and June 2014 as revealed by NASA’s Mars Reconnaissance Orbiter (MRO). A previous image showed only ancient cratered terrain.

Before (left) and after photos show relatively smooth plain with numerous older crater and the fresh impact (right). Credit: NASA/JPL/Univ. of Arizona

The impact exposed removed the ubiquitous orange-hued dust to reveal darker materials beneath the surface. The crater’s rim has a sharp outline showing virtually zero erosion. Some of the smaller, irregular divots near the strike were formed when huge chunks of rock from the impact fell back to the surface creating secondary craters.

A closer-in view shows how sharp and fresh the crater’s rim is. One way astronomers estimate relative ages of craters by examining how sharp or soft their rims appear. Click for hi-res image. Credit: NASA/JPL/Univ. of Arizona

This is far from the first fresh crater recorded at Mars by orbiting spacecraft. More than 400 have been found over the years as researchers pour over the hundreds of thousands of images returned by probes like MRO. Although I have no indication how large our featured crater is, the largest new crater ever discovered on the planet measures 161 feet (49-meters) or half the length of a U.S. football field.

How Mars’ largest new crater was discovered

We wrap up today with a big smile from the Red Planet’s south polar cap. MRO takes images throughout the Martian year (687 Earth days) of the polar regions to document changes in carbon dioxide ice coverage. Mars’ polar regions contain both water and CO2 ices which vaporize in the spring and summer heat, causing the caps to shrink back toward their respective poles.

The residual polar cap at Mars south pole in the summer season is rich in carbon dioxide or dry ice. Ice vaporizing in sunlight created as series of low mounds that resemble a smiling face. Click to enlarge. Credit: NASA/JPL/Univ. of Arizona

This fun photo was taken last November 30th and depicts an area about 1/3-mile across (500 meters) that resembles a smiley face. Just as sunlight and wind sculpts wild patterns in snow and ice on Earth, so too on Mars.

Stargazing on Christmas night

Merry Christmas and a happy holiday! I hope you’re enjoying time with family and friends and a clear night is in the forecast. Should you poke your head out tonight, here’s what’s up.

Look for the crescent moon and Mars in the southwestern sky at the end of twilight tonight December 25th. Comet Finlay and Mars will still be tight the next few nights.  The alignment is line-of-sight only — the two are actually about 45 million miles apart. Stellarium

At nightfall, a pretty crescent moon ornaments the dim constellation of Capricornus not far from Mars. Barely half a degree to the planet’s east a 6-inch or larger telescope will net you Comet 15P/Finlay, now fading from its recent outburst. It’s currently magnitude 9.6 with a little tail pointing to the east.

Comet 15P/Finlay passed only 1/6th of a degree from Mars on December 23-24. This photo was taken on the 24th and shows the glaring planet and comet almost touching. Click for a map to help you find Finlay in your telescope. Credit: Damian Peach

In a remarkable coincidence, comets have passed very close to the planet Mars twice this year. Comet Siding Spring drew physically close on and around October 19th, while Comet Finlay only appears next to the planet thanks to a lucky line-of-sight alignment.

A grand entry of stars dances across the southeastern sky around 10 o’clock local time. Comet C/2014 Q2 Lovejoy will be 10° high at that hour in the constellation Columba the Dove as seen from the northern U.S. and even higher from the central and southern states. Stellarium

Later tonight, around 10 o’clock, look to the south. Orion has now climbed boldly into view along with sparkling Sirius and the “Winter Triangle” figure. Tucked below Lepus the Hare you’ll find our Christmas comet, Lovejoy, now glowing at magnitude 5.5 and faintly visible to the naked eye from a dark sky location. Binoculars show it as a big ball of fuzz. For more information and a map showing its travels in the coming nights, click HERE.

Comet Lovejoy on December 23 looks like a Roman candle with a blue coma and long, faint tail. Credit: Michael Jaeger

Photos of Lovejoy show a huge coma or comet atmosphere more than half the size of the full moon tinted green from fluorescing carbon and cyanogen molecules; its super-skinny tail glows blue from light given off by carbon monoxide excited by ultraviolet light from the Sun.

Jupiter is easy to see now in the eastern sky in Leo around 10 o’clock local time. Stellarium

If you now direct your gaze to the east around 10 p.m., Jupiter jumps right out. After Sirius and the moon, it’s the brightest nighttime object the sky this winter. Use the planet to help you find the Sickle or head of Leo the Lion and its brightest star, Regulus.

Jupiter in binoculars tonight around 10 p.m. (CST). All four of its bright moons will be strung out in a nearly straight line very close to the planet (big glow at center). Stellarium

Sharply-focused and steadily held 10x binoculars will show all four of its bright moons, assuming one or more aren’t passing either behind or front of the planet or in eclipse. Lucky for us, Io, Europa and Ganymede will line up in a neat row east of Jupiter with Callisto well off to its west tonight. How many will you see?

Wow! What a blast. This fireball lit up Japanese skies early this morning. The Belt of Orion is at upper right. Credit: SonotaCo

Finally, reports are coming in about a powerfully bright fireball that streaked across Japan’s skies around 2 a.m. local time this Christmas morning. I’ve not been able to track down a brightness estimate, but the pictures show an object at least as brilliant as the full moon.

Comet Finlay outburst another present under the Christmas tree

Morphing from obscurity to prominence, Comet 15P/Finlay shows off a beautiful finger-shaped tail, a bright nucleus and several rays in this photo taken December 19th. It orbits the Sun every 6.5 years. Credit: Damian Peach

Surprise! An obscure comet that only amateur astronomers would pay attention to experienced a sudden outburst in brightness earlier this week putting it within range of telescopes as small as 4.5 inches.

Comet 15P/ Finlay hunkered along at a dim 11th magnitude successfully avoiding the limelight until about December 16th. That’s when Czech comet observer Jakub Cerny and his team took a photo revealing the comet had surged in brightness by some 8 times to magnitude 8.7. Suddenly, Finlay became a minor celebrity.

Comet Finlay on December 16th shows a bright coma and short tail. Its sudden rise to 9th magnitude was confirmed on December 18th by Australian comet observers. The moderately condensed object is about 3 arc minutes in diameter. Credit: J. Cerny, M. Masek, K. Honkova, J. Jurysek, J. Ebr, P. Kubanek, M. Prouza, M. Jelinek

It still remains in outburst visible low in the southwestern sky very close to the planet Mars, which serves as a convenient “pointer” to help us find it. From mid-northern latitudes, Comet Finlay is best viewed as soon as evening twilight ends, when highest in the sky. The moon, ever a spoiler when it comes to viewing fuzzy stuff like comets and galaxies, won’t be over-bright until after Christmas, leaving us almost a nearly week-long window for finding and tracking the comet before it fades.

Use the general map to take you to Mars and then the more detailed version to pinpoint the comet’s location. Finlay will look like a small, fuzzy spot with perhaps a faint tail to the east visible depending on the size of your telescope.

To find the comet, first find Mars. Face west toward the brilliant star Vega and shoot a line from it through Altair and straight to Mars, low in the southwestern sky in Capricornus. Map time is around 6:15 p.m. CST, end of evening twilight in late December. Source: Stellarium

Planet and comet paths are currently converging toward conjunction. On December 23rd and 24th Mars and Finlay will be separated by just 10 arc minutes or 1/3 the diameter of the Full Moon. By December’s end they’ll gradually separate as each follows its own orbital path around the Sun. The close pairing is line of sight only.

Comet Finlay tracks alongside Mars through early January. On December 23rd, they’ll come together in a remarkably close conjunction. This map shows the nightly position of the comet from Dec. 18th through Jan. 12th. Mars’ location is shown every 5 nights. Positions plotted for 6:15 p.m. (CST). Stars shown to magnitude 8. Star magnitudes are underlined. Click for a large version you can print for outside use. Source: Chris Marriott’s SkyMap software

We’ve known about Comet Finlay since September 26, 1886, when William Henry Finlay happened across it with his 7-inch telescope from the Cape of Good Hope in South Africa. He described humanity’s first view of the object as round, 1 arc minute in diameter and “very slightly more condensed towards the centre.”

Animated movie showing the expansion of the coma of Comet 17P/Holmes over 9 nights during its spectacular outburst in November 2007. Credit: 3.6-meter Canada-France-Hawaii telescope on Mauna Kea / David Jewitt

Finlay reaches perihelion or closest approach to the Sun on December 27th and was expected to brighten to magnitude +10 when nearest Earth in mid-January at 130 million miles (209 million km). This month’s outburst may change that prediction.

What causes a comet to quickly and unpredictably surge in brightness still baffles astronomers. Unlike most rocky asteroids, comets are friable creatures. They crumble easily. It’s thought that sub-surface ices, warmed by a comet’s approach to the Sun, vaporize, creating pressurized pockets of gas that break through the overlying ice above, sending fragments flying and exposing fresh new ice.

Sunlight gets to work vaporizing both the newly exposed vents and aerial shrapnel. Large quantities of dust trapped in the ice are released and glow brightly in the Sun’s light, causing the comet to suddenly brighten.

Comet Lovejoy Q2 looks like a spectacular aerial burst in this photo taken December 20, 2014. The comet’s still low in the southern sky from mid-northern latitudes but will be soon be well-placed for binocular viewing in a few days. Credit: Martin Mobberley

So now we have two fairly bright comets during the holidays – Finlay and Comet C/2014 Q2 Lovejoy. Lovejoy has been steadily brightening and now glows at around magnitude 5.5, bright enough for observers with dark skies to see it with the naked eye. Click HERE for more information and a finder chart for it.

While this means we have two cometary gifts under the Christmas tree, by all means, don’t wait until Christmas to unwrap either. Have at them the next clear night!

Who or what passed gas on Mars?

A photo taken today, December 19th, of sand dunes and rock outcrops around the Curiosity rover through the fisheye lens of one of its Hazard Avoidance Cameras. Colorized by the author. Credit: NASA/JPL-Caltech

What a tantalizing week it’s been for organic chemistry on Mars. We learned that NASA’s Curiosity rover measured a tenfold spike in methane, an organic chemical, in the atmosphere around it and detected other organic molecules in a rock-powder sample collected by its drill.

Scatalogical references to the contrary, methane is a colorless and odorless gas. While it’s a component of both human and bovine flatulence, what gives human “gas” its odor are sulfur compounds, principally hydrogen sulfide and methyl mercaptan, which by the way we share with skunks.

But I digress.

This image illustrates possible ways methane might be added to Mars’ atmosphere and removed from it and stored in “sinks”. The Curiosity rover has detected changes in methane concentration in the atmosphere, implying both types of activity occur on modern Mars. More details of methane’s formation and movement on the planet are given below. Credit: NASA/JPL-Caltech/SAM-GSFC/Univ. of Michigan

“This temporary increase in methane — sharply up and then back down — tells us there must be some relatively localized source,” said Sushil Atreya of the University of Michigan, Ann Arbor, and Curiosity rover science team. “There are many possible sources, biological or non-biological, such as interaction of water and rock.”

Methane molecule

The sudden increase and decrease immediately gets the heart palpitating. Sure sounds like the work of a living being, but methane, a simple organic molecule made of one carbon atom festooned by four hydrogen atoms, can be created in a number of different ways. Bacteria make methane by combining carbon dioxide and hydrogen; the energy liberated in the process powers their minute lives.

Chemical reactions between water and the minerals olivine and pyroxene in rock also release methane as does the action of ultraviolet light from the Sun on organic materials like comet dust and other meteoric material on Mars. Whether manufactured through living or non-living processes, methane generated underground can become trapped within the crystal structure of water to form a curious substance called clathrate, a form of methane ice.

This 98-foot-wide (30-meter) crater spotted in Siberia this past summer was probably caused by the release of methane gas from permafrost. Click to learn more about it. Credit: Yamalo-Nenets Autonomous Okrug Governor

Meteor impacts, faults or cracks in the Martian crust and simple outgassing can then release methane at a later date. Earth has abundant methane clathrates buried beneath deep ocean sediments and stored in permafrost. We hope it stays there. Methane is a powerful greenhouse gas that already plays a role in climate change. Unlike chocolate, more of it isn’t a good thing.

Since Mars is a windy planet, any methane released is likely to quickly thin out and be dispersed. Methane can be removed from the atmosphere through “photochemistry” or the sunlight’s UV light sparking chemical reactions among molecules. These reactions can oxidize the methane, through intermediary chemicals such as formaldehyde and methanol, into carbon dioxide, the predominant ingredient in Mars’ atmosphere.

This graphic shows tenfold spike in the amount of methane in the Martian atmosphere surrounding the Curiosity rover as detected by a series of measurements made with the Tunable Laser Spectrometer instrument in the rover’s Sample Analysis at Mars laboratory suite. Credit: NASA/JPL-Caltech

Researchers used Curiosity’s onboard Sample Analysis at Mars (SAM) laboratory a dozen times in a 20-month period to sniff methane in the atmosphere. During two of those months, in late 2013 and early 2014, four measurements averaged seven parts per billion. Before and after that, readings averaged only one-tenth that level.

Whatever its origin, we’re not talking much gas – Earth’s atmosphere, of which methane is a minor constituent, averages 1,800 parts per billion. Cattle belching alone accounts for 16% of that total.

Curiosity also detected different Martian organic chemicals in powder drilled from a rock dubbed Cumberland, the first definitive detection of organics in surface materials of Mars. These Martian organics could either have formed on Mars or been delivered to Mars by meteorites.

There’s abundant evidence for Mars once being a wetter world. These riverbeds, called Nanedi Valles, flowed with water about 3.8 billion years ago. Credit: ESA

As we saw with methane, organic or carbon-containing materials aren’t necessarily an indicator of little green bugs. They can form and be left in rocks through inorganic processes, too. There’s simply no way to know from the Curiosity data how they originated, but they do give us hope that Mars was once (and may still be) a planet favorable to life.

Identifying which specific Martian organics are in the rock is complicated by the presence of perchlorate minerals in Martian rocks and soils. Perchlorates are toxic salts used for propellents here on Earth because they have explosive properties. When heated inside SAM, the perchlorates alter the structures of the organic compounds, masking the identities of the organics in the sample.

Curiosity also revealed some interesting news about the past water in the Martian atmosphere. According to its measurements, the Cumberland rock formed 3.9 to 4.6 billion years ago and contains just half the ratio in water vapor in today’s Martian atmosphere. This suggests that much of the planet’s water loss occurred since that rock formed.

View of a rocky desert-like landscape inside Gale Crater snapped by Curiosity on December 14th. Colorized by the author. Credit: NASA/JPL-Caltech

On the other hand, the ratio is about three times higher than that estimated in the original water supply of Mars. This suggests much of Mars’ original water was lost before the rock formed. More information please!

Additional samples along with data from the NASA’s MAVEN mission, which is conducting a study of the planet’s atmosphere to determine where both the water and air disappeared to, will hopefully give us a clearer picture of the Red Planet’s evolution from a water world like Earth to the present cold, dry desert.

In more recent news, NASA and an international team of planetary scientists have found evidence in meteorites on Earth that indicates Mars had yet another global reservoir of water or ice near its surface. Check out the details HERE.

Source information in today’s blog

Curiosity Rover discovers Gale Crater was once a massive lake

Simulated view of Gale Crater Lake on Mars receiving runoff from snow melting on the crater’s northern rim. Evidence that NASA’s Curiosity rover has found of ancient streams, deltas and lakes suggests the crater held a lake such as this more than three billion years ago.  Credit: NASA/JPL-Caltech/ESA/DLR/FU Berlin/MSSS

Evidence gathered by NASA’s Curiosity Rover during its 2-year-plus study of soil and rocks in Gale Crater points to a startling conclusion: this 96-mile-wide crater once held a lake some 900 feet deep.

Gale Crater now with Mt. Sharp at center. Credit: NASA/JPL-Caltech

Mount Sharp, the crater’s broad central peak, stands about 3 miles (5 km) tall and was built by sediments deposited in the lake over tens of millions of years by wind, rivers and material settling to the lake bottom. Curiosity is currently investigating the lower 500 feet (150-meters) of sedimentary rock at the base of the mountain where hundreds of layers of rock are exposed like so many layers of a Vienna torte.

This picture shows a vertical cross section through geological layers deposited by rivers, deltas and lakes. Deposits from a series of successive deltas build out increasingly high in elevation as they fan out toward the center of the crater over the lake deposits. 10 centimeters equals about 4 inches. Credit: NASA/JPL-Caltech/Imperial College

All this activity occurred an estimated 3 billion years ago when the atmosphere of Mars had to be much denser than it is today. For water to exist out in the open on a planet, sufficient atmospheric pressure is needed to prevent it from vaporizing into thin air. Literally. Mars’ atmospheric pressure today is 1/1000 that of Earth, much too tenuous to keep water down.

“We are making headway in solving the mystery of Mount Sharp,” said Curiosity Project Scientist John Grotzinger of the California Institute of Technology in Pasadena. “Where there’s now a mountain, there may have once been a series of lakes.”

This view from the Mastcam on NASA’s Curiosity Mars rover shows an example of cross-bedding that results from water passing over a loose bed of sediment in one direction and then another. It was taken Nov. 2, 2014, at a target called “Whale Rock” within the “Pahrump Hills” outcrop at the base of Mount Sharp. Credit: NASA/JPL-Caltech/MSSS

Only problem is, scientists still can juggle the models to arrive at a satisfactory explanation for why the Martian climate was so radically different in the distant past. Hypotheses abound. Was it the decay of the planet’s magnetic field and stripping of its atmosphere by the solar wind or did intense asteroid bombardment send it flying into the vacuum of space?

Whatever happened, over time, the water evaporated, vaporized or seeped away, and sediments hardened into rock. Winds howling for hundreds of millions of years carved away at the material between the crater’s rim and what is now the edge of the expansive Mt. Sharp, exposing layer upon layer of the crater’s past.

This series of images reconstructs the geology of the region around Mars’ Mount Sharp, where NASA’s Curiosity Mars rover is now exploring. The images, taken on Earth, have been altered for the illustration of how sediments can accumulate in alternating dry periods and wet periods. A dry period is shown at left, wet at center and dry again at right. Over time, sediments accumulate and are piled higher on the crater floor through the action of water. Credit: NASA/JPL-Caltech

“We found sedimentary rocks suggestive of small, ancient deltas stacked on top of one another,” said Curiosity science team member Sanjeev Gupta of Imperial College in London. “Curiosity crossed a boundary from an environment dominated by rivers to an environment dominated by lakes.”

Scientists are left with a conundrum — how did Mars produce the conditions that would keep liquid water stable for millions of years, long enough for lakes and rivers to deposit hundreds of feet of sediments? For now, it’s just enough to know it happened, and that what appears to be a dusty, rocky depression once held more water than Lake Erie.

 

The Moon, still young after all these years / See a Callisto eclipse!

The Moon and Mars gather in the west at dusk this evening. Stellarium

Tonight the returning young crescent Moon puts down stakes near the planet Mars in Sagittarius. Look for the pair low in the southwestern sky at dusk.

We’re used to hearing how ancient the Moon is. Its origin goes back to 4.48 billion years ago when a Mars-sized planet sideswiped the Earth, blasting debris into space that quickly coalesced into our satellite. While it’s true that most of the Moon’s crust and craters date from then, recent close-up photos from NASA’s Lunar Reconnaissance Orbiter (LRO) suggest the Moon remained volcanically active until not that very long ago. At least on geological time scales.

Ina Caldera, a classic IMP, sits atop a low, broad volcanic dome or shield volcano, where lava once oozed from the moon’s crust. The darker patches in the photo are blobs of older lunar crust. They  form a series of low mounds higher than the younger, jumbled terrain around them. Credit: NASA

100 million years ago, when dinosaurs cracked jokes about the early mammals, lava oozed from cracks in the Moon’s crust to create what astronomers nowadays call IMPs or Irregular Mare Patches. They’re characterized by a mixture of smooth, shallow mounds next to patches of rough, blocky terrain. Only one, called Ina, is large enough to see in amateur telescopes. The others, liberally sprinkled across the lunar nearside, are generally less than 1/3 mile (500 m) across. Using the LRO, a team of researchers led by Sarah Braden of Arizona State University has found 70 landscapes similar to Ina.

When it comes to the big picture, 100 million years is a small slice of Earth’s history. Credit: NASA

Maria (plural of “mare”) are those big dark spots the make up the face of the man in the moon. They’re actually huge expanses of lava that welled up from cracks in the Moon’s crust several billion years ago after asteroid impacts. IMPs are much more recent. Some may be as “young” as 50 million years old. This was well after the dinosaurs succumbed to major climate changes induced by the impact of a 6-mile-wide asteroid hit here on Earth. Now the mammals are cracking jokes about the dinos.

A selection of some of the 70 IMPs discovered during the survey. Credit: NASA

“Discovering new features on the lunar surface was thrilling!” says Braden. “We looked at hundreds of high-resolution images, and when I found a new IMP it was always the highlight of my day.”

Astronomers determine ages of lunar features by doing crater counts. The more lightly cratered an area is, the younger.

Here’s the scene tomorrow morning November 26th with all four of Jupiter’s bright moons. Callisto, which sits right next to Europa, will dramatically fade over several minutes time starting about 4:50 a.m. CST. Meanwhile, 15 minutes later at 5:05 a.m., Ganymede will exit its eclipse and return to view. Add one hour for EST, subtract an hour for MST and two hours for PDT. South is up. Stellarium

Some of you may be early morning observers. Well, I’ve got a special event to share with you. Tomorrow morning November 26th, Jupiter’s bright moon Callisto will be eclipsed by Jupiter’s shadow starting at 4:50 a.m. (CST) and disappear for nearly five hours.

Just 15 minutes after Callisto disappears, Ganymede emerges from eclipse at 5:05 a.m. (CST). One disappears, the other reappears. Pretty cool! Jupiter will be the brightest thing in the sky high in the south in Leo at the time. You can always find out what Jupiter’s moons anytime of day or night by visiting Sky and Telescope’s Jupiter’s Moons site.

What’s inside Mars? We’ll need InSight to find out

This artist’s concept depicts the stationary NASA Mars lander known by the acronym InSight at work studying the interior of Mars with a probe to measure heat flowing through the planet’s crust. The solar cells provide power to the lander. The mission will be an international one with instruments provided by several different space agencies. Credit: NASA

We’ve photographed Mars from orbit, drilled into its surface and sniffed its atmosphere looking for clues on how a warmer, wetter world went cold and dry. Now it’s time to go deep.

NASA’s InSight Mars Lander just before propulsion pressure testing in a Lockheed Martin clean room. Credit: NASA/Lockheed Martin

In March 2016, NASA plans to launch the InSight Mission that will place a single lander on Mars to study its deep interior. Named InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport), it will land in September and spend the next two years investigating the planet’s interior to determine the makeup of the Martian core, the thickness of the the crust and the composition of the mantle, the broad zone of rock between crust and core.

Using the SEIS seismometer, we’ll learn about the number and distribution of marsquakes caused by both internal stresses and meteorite impacts. The information will also help us unravel the structure of Mars’ hidden interior just as the study of earthquakes here on Earth has taught us much about the internal structure of the ball beneath our feet. We know that Earth’s center is avocado-like with a solid inner core of iron-nickel surrounded by a softer, liquid outer core.

Artist concept of the interior of Mars. Mars has a low density compared to the other rocky planets leading astronomers to believe it has less iron in its core. The lack of a global magnetic field around the planet also suggests the core is solid. Currents within Earth’s liquid outer core are believed responsible for generating the planet’s magnetic field. Credit: NASA-JPL-Caltech

The lander packs a unique “mole” or heat probe that can hammer over 16 feet (5-meters) into the Martian crust, deeper than all previous drills, scoops, arms and probes, to learn how much heat flows from the planet’s interior. As the mole burrows down in the crust it will pull a tether of heat sensors along to measure the increase in temperature with depth. Heat flow sounds obscure but it’s critical in understanding where and how mountain ranges and volcanoes form.

Another experiment, the Rotation and Interior Structure Experiment or RISE, will use variations in the receive time of the lander’s radio signals to measure minute wobbles in Mars’ rotation axis that will tell us more about the size of the core and whether it’s solid or not.

InSight will land near Mars’ equator not far from the Curiosity Rover. Credit: NASA

Because Mars has been less geologically active than the Earth – it lacks plate tectonics that recycles and renews its crust – it actually retains a more complete record of its history in its own basic planetary building blocks of core, mantle and crust. Scientists hope that insights from InSight will help us understand the forces that shaped not only Mars but all the rocky planets across the solar system.

Three ancient volcanoes rise from the the giant bulge on Mars known as Tharsis in this Viking 1 image taken in 1980. From bottom to top: Arsia Mons, Pavonis Mons and Ascraeus Mons. It’s thought that Tharsis overlies an enormous hot spot where huge quantities of lava were released as long ago as 3.7 billion years to create both the bulge and volcanoes. The cracks may have formed from the weight of the overlying lavas. Credit: NASA

Don’t forget the cameras! InSight will carry a navigation camera similar to those on the the Mars rovers mounted on the lander’s arm. In addition to black and white panoramas, it will shoot photos of the instruments on the lander’s deck and a 3-D view of the ground where the seismometer and heat flow probe will be placed. Mission controllers will also use it to guide them in the placing of the instruments to the ground. A second wider angle camera like the hazcams on the rovers will provide a second perspective on the scene.

I don’t know about you, but I can never get enough Mars. I’m eager to see the mission underway.

Spectacular meteor storm lights up Mars during recent comet flyby

On October 19, when Comet C/2013 A1 Siding Spring flew just 87,000 miles from Mars, dust from its tail set the sky aglow with a meteor storm. This illustration is my feeble attempt to show what you might have seen standing on Mars next to the Curiosity rover at the time. Credit: NASA (background) with additions and changes by Bob King

Oh, to have stood under the Martian sky on October 19th! As Comet Siding Spring passed just 87,000 miles (140,000 km) from the planet that night, dust in its tail slammed into the Martian atmosphere at 126,000 mph, burning up in storm of meteoric madness. “Thousands per hour fell,” said Nick Schneider, instrument lead for NASA’s MAVEN Imaging Ultraviolet Spectrograph. It must have looked like those classic illustrations of the 1833 and 1866 Leonid meteor storm back here on Earth.

Composite image of Comet Siding Spring and Mars taken by the Hubble Space Telescope. The images have been added together to create a single picture to illustrate the true distance or separation (1/20th the apparent size of the Full Moon) between the comet and Mars at closest approach.  Credit: NASA/ESA

I participated in a teleconference yesterday with principal investigators for the instruments on the Mars Reconnaissance Orbiter (MRO), MAVEN and Mars Express spacecraft pressed into service to study Comet Siding Spring during its historic flyby. The comet is a visitor from the faraway Oort Cloud, a spherical repository of billions of icy comets up to 1 light year from the Sun. Some 4-5 Oort Cloud comets swing through the inner solar system every year; this is the first one we’ve ever studied up close. It was discovered at Siding Spring Observatory in Australia by Robert McNaught on January 13, 2013.

NASA’s MAVEN uses its IUVS to perform a scan of the Martian atmosphere along its limb. Scans found enhanced levels of metals from vaporizing comet dust. Credit: NASA

“Dust slammed into the atmosphere and changed the chemistry of the upper atmosphere,” said Jim Green, director, Planetary Science Division, NASA Headquarters in Washington. Data from MAVEN’s UltraViolet Spectrograph (IUVS), which scans of Mars’ upper atmosphere in UV light to determine its chemical makeup, saw big spikes in the amount of magnesium and iron during the flyby. These elements are commonly found in meteorites.

Before and after scans by MAVEN. At left is a profile of the atmosphere before the comet’s arrival showing carbon dioxide and other gases; at right is during the comet’s pass. Check out that huge spike to the right – that from magnesium. Elevated levels to the left indicate iron. Credit: NASA

Siding Spring turned out to be much dustier than expected, prompting Green to later add: “It makes me very happy hid them (spacecraft) on the backside of Mars.” “It really saved them. Even one well-placed hit from a high-speed dust particle could damage an instrument, and Siding Spring peppered the Martian atmosphere with “several tons” of dust.

MAVEN used its mass spectrometer – an instrument that identifies elements by how much mass they have – to record a big enhancement of the elements magnesium, manganese, iron and others from comet dust in Mars’ atmosphere. Credit: NASA

Meanwhile, MAVEN’s Neutral Gas and Ion Mass Spectrometer (NGIMS), picked up major spikes in 8 different metals from ablating comet dust including sodium, magnesium, iron and nickel. Jim Green pointed out that the increase in sodium may have tinged the twilight sky with a yellow glow. That and a recent increase in the amount of dust in the atmosphere over the Curiosity rover site may be the reason the comet was so difficult to photograph from the ground.

Only hours after Comet Siding Spring’s closest approach, dust particles hitting air molecules on Mars formed a temporary ionized (electrified) layer in its lower ionosphere 50-60 miles high. Credit: ESA

So we have a very dusty comet, a big meteor storm, the atmosphere spiced up with metals from burning dust.

Anything else? Heck, yes. The European Space Agency’s Mars Express Orbiter used its radar to send out radio waves of very low frequency down through Mars atmosphere to record the state of the ionosphere, a rarified layer of air between 60-250 miles (100-400 km) high. At the comet’s closest approach, the ionosphere was normal, but 7 hours later, impacting dust had created a brand new, temporary ionization layer.

Close-ups pictures taken by the Mars Reconnaissance Orbiter of Comet Siding Spring around the time of closest approach to Mars. They show the combined light of the tiny nucleus and much larger coma or comet atmosphere. Comet dust / rocks range in size from 1/1000 of a millimeter to 1 centimeter (~1/2-inch). Credit: NASA

The high resolution camera on the MRO photographed brightness variations in the comet’s light, nailing down its rotation period to 8 hours. But size-wise, we’re a little less clear. Estimates for the comet’s nucleus range from 984 feet to 1.2 miles (300-m to 2 km). For comparison, Comet 67P/Churyumov-Gerasimenko, currently orbited by Europe’s Rosetta spacecraft, is 1.5 miles (2.4 km) across.

Color variations in this photo by CRISM indicate different sized dust particles being ejected by the comet. Credit: NASA

Yet another instrument named CRISM (Compact Reconnaissance Spectrometer for Mars) made some intriguing measurements of the coma showing distinct differences in color – red here, blue there – indicating the comet is blowing out dust particles of different sizes.

As scientists continue to analyze the data collected by the fleet of space probes, we’ll see more papers and results soon. For now, the rare opportunity to study a comet up close from another planet was an unqualified success. You can listen to the replay of the hour-long conference HERE.