Category Archives: Space Science

Space sciences roundup – Nov.6.2019

A sampling of recent articles, videos, and images from space-related science news items (find previous roundups here):

Exoplanets

** TESS (Transiting Exoplanet Survey Satellite) has found 29 exoplanets so far in a survey of southern sky: NASA’s TESS Presents Panorama of Southern Sky | NASA

… Constructed from 208 TESS images taken during the mission’s first year of science operations, completed on July 18, the southern panorama reveals both the beauty of the cosmic landscape and the reach of TESS’s cameras.

“Analysis of TESS data focuses on individual stars and planets one at a time, but I wanted to step back and highlight everything at once, really emphasizing the spectacular view TESS gives us of the entire sky,” said Ethan Kruse, a NASA Postdoctoral Program Fellow who assembled the mosaic at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

Within this scene, TESS has discovered 29 exoplanets, or worlds beyond our solar system, and more than 1,000 candidate planets astronomers are now investigating.

TESS divided the southern sky into 13 sectors and imaged each one of them for nearly a month using four cameras, which carry a total of 16 charge-coupled devices (CCDs). Remarkably, the TESS cameras capture a full sector of the sky every 30 minutes as part of its search for exoplanet transits. Transits occur when a planet passes in front of its host star from our perspective, briefly and regularly dimming its light. During the satellite’s first year of operations, each of its CCDs captured 15,347 30-minute science images. These images are just a part of more than 20 terabytes of southern sky data TESS has returned, comparable to streaming nearly 6,000 high-definition movies.

Solar system

** “Encounter with Ultima Thule: The Most Distant Object Humanity Has Ever Explored”

After encountering Pluto, the New Horizons spacecraft, for the first time flew by a member of the Kuiper Belt of icy objects beyond Neptune. This particular object, informally named “Ultimate Thule” (meaning the farthest place beyond the known world,) turned out to be a “contact binary” – two smaller icy worlds stuck together. Dr. Moore shares an insider’s view (with great images) of how the mission got there and what we learned at Ultima Thule.

Asteroids

** “ESO Telescope Reveals What Could be the Smallest Dwarf Planet Yet in the Solar System” | ESO

Astronomers using ESO’s SPHERE instrument at the Very Large Telescope (VLT) have revealed that the asteroid Hygiea could be classified as a dwarf planet. The object is the fourth largest in the asteroid belt after Ceres, Vesta and Pallas. For the first time, astronomers have observed Hygiea in sufficiently high resolution to study its surface and determine its shape and size. They found that Hygiea is spherical, potentially taking the crown from Ceres as the smallest dwarf planet in the Solar System.

As an object in the main asteroid belt, Hygiea satisfies right away three of the four requirements to be classified as a dwarf planet: it orbits around the Sun, it is not a moon and, unlike a planet, it has not cleared the neighbourhood around its orbit. The final requirement is that it has enough mass for its own gravity to pull it into a roughly spherical shape. This is what VLT observations have now revealed about Hygiea.

“A new SPHERE/VLT image of Hygiea, which could be the Solar System’s smallest dwarf planet yet. As an object in the main asteroid belt, Hygiea satisfies right away three of the four requirements to be classified as a dwarf planet: it orbits around the Sun, it is not a moon and, unlike a planet, it has not cleared the neighbourhood around its orbit. The final requirement is that it have enough mass that its own gravity pulls it into a roughly spherical shape. This is what VLT observations have now revealed about Hygiea.” – ESO

The making of a dwarf planet:

Computational simulation of the fragmentation and reassembly that led to the formation of Hygiea and its family of asteroids, following an impact with a large object. While changes in the shape of Hygiea occur after the impact, the dwarf-planet candidate eventually acquires a round shape.

** The story of Professor Amy Mainzer  and the NEOCam space asteroid observatoryOne scientist’s 15-year (and counting) quest to save Earth from asteroid impacts – The Space Review

NEOCam is a 50-centimeter telescope that will discover and characterize a large fraction of the asteroids and comets in the inner part of the solar system. It was supported based on its fundamental science, but the data that it will produce also serves planetary defense, which can be considered applied science. NASA administrator Jim Bridenstine has been called “passionate” about planetary defense and the American public agrees: in a recent AP-NORC poll of US priorities in space, monitoring asteroids was considered top priority by 68 percent of those polled, higher than any other category (59 percent prioritized scientific research and exploration; 23 percent and 27 percent prioritized human exploration of the Moon and Mars, respectively; and 19 percent prioritized a US military presence in space.) Imagine how much any presidential candidate would like to poll at 68 percent!

Sun

** The sun remains nearly spotless: Sunspot update October 2019: Sunspot activity continues to flatline | Behind The Black

Even though the previous 2008-2009 solar minimum was one of the deepest and longest ever recorded, the lack of sunspots in the past five months has significantly beaten it for inactivity, as shown on the first graph above. That previous minimum never had a period of even two months with so few sunspots. Furthermore, the Sun has now been blank 74% of the time in 2019, a record of blankness that beats the yearly record of either 2008 or 2009. If the Sun continues to be as blank as it has been for the next two months, 2019 will easily set the record for the year with the fewest sunspots ever recorded.

The big question remains: Are we heading for a grand minimum with no sunspots for decades? We still do not know. Even these unprecedented trends prove nothing, as we really do not yet have a clear understanding of why the Sun undergoes these various cycles of sunspot activity/inactivity. The Sun could still come back to life in the coming years. We can only wait and see.

Astronomy

** The captivating beauty of a galactic smashup: Hubble Captures Cosmic Face | ESA/Hubble

“This new image from the NASA/ESA Hubble Space Telescope captures two galaxies of equal size in a collision that appears to resemble a ghostly face. This observation was made on 19 June 2019 in visible light by the telescope’s Advanced Camera for Surveys. Residing 704 million light-years from Earth, this system is catalogued as Arp-Madore 2026-424 (AM 2026-424) in the Arp-Madore “Catalogue of Southern Peculiar Galaxies and Associations”.” – ESA/Hubble

Although galaxy collisions are common — especially in the early universe — most are not head-on impacts like the collision that likely created this Arp-Madore system 704 million light-years from Earth. This violent encounter gives the system an arresting ring structure, but only for a short amount of time. The crash has pulled and stretched the galaxies’ discs of gas, dust, and stars outward, forming the ring of intense star formation that shapes the “nose” and “face” features of the system.

Ring galaxies are rare, and only a few hundred of them reside in our larger cosmic neighbourhood. The galaxies have to collide at just the right orientation so that they interact to create the ring, and before long they will have merged completely, hiding their messy past.

** Heavy element production seen at site of a neutron star collision that was spotted with gravitational wave detection: First identification of a heavy element born from neutron star collision | ESO

For the first time, a freshly made heavy element, strontium, has been detected in space, in the aftermath of a merger of two neutron stars. This finding was observed by ESO’s X-shooter spectrograph on the Very Large Telescope (VLT) and is published today in Nature. The detection confirms that the heavier elements in the Universe can form in neutron star mergers, providing a missing piece of the puzzle of chemical element formation.

In 2017, following the detection of gravitational waves passing the Earth, ESO pointed its telescopes in Chile, including the VLT, to the source: a neutron star merger named GW170817. Astronomers suspected that, if heavier elements did form in neutron star collisions, signatures of those elements could be detected in kilonovae, the explosive aftermaths of these mergers. This is what a team of European researchers has now done, using data from the X-shooter instrument on ESO’s VLT.

The Moon

** China’s lunar far-side exploration mission continues. Both the Yutu-2 rover and Chang’e-4 lander are demonstrating impressive resilience after multiple exposures to the deep cold of the 2 week long lunar nights. (Each uses a radioisotope heater unit to stay warm.) China’s lunar rover travels over 300 meters on moon’s far side – Xinhua

China’s lunar rover Yutu-2 has driven 318.62 meters on the far side of the moon to conduct scientific exploration of the virgin territory.

Both the lander and the rover of the Chang’e-4 probe have ended their work for the 11th lunar day, and switched to dormant mode for the lunar night on Monday (Beijing time), according to the Lunar Exploration and Space Program Center of the China National Space Administration.

The rover is now located 218.11 meters northwest of the lander.

The scientific tasks of the Chang’e-4 mission include conducting low-frequency radio astronomical observation, surveying the terrain and landforms, detecting the mineral composition and shallow lunar surface structure and measuring neutron radiation and neutral atoms.

** India’s Chandrayaan-2 orbiter starting to produce data from the 8 instruments aboard the spacecraft. The first findings include the detection of Argon-40 in the tenuous lunar atmosphere using a mass spectrometer and images with the Dual-Frequency Synthetic Aperture Radar (DF-SAR) that highlight the structures of image craters.

An initial image of the lunar surface from the Dual-Frequency Synthetic Aperture Radar (DF-SAR) on Chandrayaan-2. Credits: ISRO

More about the orbiter:

** The LROC imager on the Lunar Reconnaissance Orbiter captures dramatic views of the Bhabha crater,  which lies within the South Pole–Aitken (SPA) basin on the Moon’s farside: Dawn Over Bhabha Crater | Lunar Reconnaissance Orbiter Camera

“Central peak complex of Bhabha crater (70 kilometer diameter) rising from the shadows of dawn, image snapped on 28 August 2019 from an altitude of 73 kiolmeters. View is seen from east-to-the west, north is to the right, visible portion of central peak complex is about 14 kilometers wide, NAC M1321101374LR [NASA/GSFC/Arizona State University].”
Suborbital space sciences

** Research on reusable suborbital rocket vehicles will be the focus of the 2020 Next-Generation Suborbital Researchers Conference (NSRC) in Broomfield, Colorado, March 2-4, 2020: Southwest Research Institute, Commercial Spaceflight Federation announce suborbital space researchers, educators conference – SwRI

The conference will provide an in-depth forum for attendees to learn more about funding and conducting research and public outreach aboard new commercial suborbital spaceflight systems — fortuitous byproducts of space tourism. Representatives from NASA, the Federal Aviation Administration, spaceports, and commercial suborbital and orbital vehicle operators will attend.

“A new era of routine access to suborbital space for researchers and educators is fast approaching,” said SwRI Associate Vice President Dr. Alan Stern, the NSRC program chair. “The 2020 conference will explore the many revolutionary ways this will affect space research and education.”

Organized by SwRI and the Commercial Spaceflight Federation (CSF), NSRC-2020 will feature dozens of keynote and invited presentations, panel discussions, workshops, aerospace tours, presentations, posters and networking opportunities.

“As a growing number of commercial space companies provide low-cost and frequent access to suborbital space for humans and research payloads, 2020 is the time to fully utilize this game-changing capability,” added Eric Stallmer, president of CSF. “NSRC-2020 will be the epicenter for researchers, educators, companies, students and entrepreneurs to connect and take part in this new era.”

NSRC is the premier conference for the suborbital space research and education community. The 2020 conference follows six previous, highly successful meetings since 2010. The program, sponsors, registration, logistics and other conference details are available at http://nsrc.swri.org.

Mars

** Insight‘s heat probe digger dug again and appeared to be doing well by getting traction from pressure put on its side by Insight’s robotic arm: Mole Digging on Mars: Breakthrough! – Leonard David – Oct.24.2019

“We have made important progress in our attempts to get the mole digging again…in fact, we got it digging again!”

That’s the word from Tilman Spohn of the German Aerospace Center’s (DLR) Institute of Planetary Research in Berlin. He’s the experiment leader on the Heat Flow and Physical Properties Package (HP3), the self-hammering “mole” designed to dig down as much as 16 feet (5 meters) and take Mars’ temperature.

“This GIF shows NASA InSight’s heat probe, or “mole,” digging about a centimeter (half an inch) below the surface last week. Using a technique called “pinning,” InSight recently pressed against the mole using a scoop on its robotic arm to help the self-hammering heat probe dig so that it can “take the temperature” of Mars.” Credits: NASA JPL

but then it went into reverse:

NASA/JPL:

After making progress over the past several weeks digging into the surface of Mars, InSight’s mole has backed about halfway out of its hole this past weekend. Preliminary assessments point to unusual soil conditions on the Red Planet. The international mission team is developing the next steps to get it buried again.

A scoop on the end of the arm has been used in recent weeks to “pin” the mole against the wall of its hole, providing friction it needs to dig. The next step is determining how safe it is to move InSight’s robotic arm away from the mole to better assess the situation. The team continues to look at the data and will formulate a plan in the next few days.

“In this image from Oct. 26, 2019 — the 325th Martian day, or sol, of the mission — InSight’s heat probe, or “mole,” is seen after backing about halfway out of the hole it had burrowed.” Credits: NASA, JPL

** Latest on Curiosity’s travels:

“NASA’s Curiosity rover took this selfie on Oct. 11, 2019, the 2,553rd Martian day, or sol, of its mission. The rover drilled twice in this location, which is nicknamed “Glen Etive.” Credit: NASA/JPL-Caltech/MSSS

** Glacier movements over the eons create striking structures at Euripus Mons: Ancient glacier flows on Mars | Behind The Black

You can see that this large apron is the result of repeated flows down from the mountain, with each new flow not quite traveling as far, creating a terraced slope extending many miles.

Euripus Mons glacier. HiRISE image cropped by Bob Zimmerman

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Space sciences roundup – Oct.18.2019

A sampling of recent articles, videos, and images from space-related science news items (find previous roundups here):

Astronomy

** A better view of an interstellar comet 2I/Borisov: Hubble Observes New Interstellar Visitor | ESA/Hubble

On 12 October 2019, the NASA/ESA Hubble Space Telescope provided astronomers with their best look yet at an interstellar visitor — Comet 2I/Borisov — which is believed to have arrived here from another planetary system elsewhere in our galaxy.

This observation is the sharpest  view ever of the interstellar comet. Hubble reveals a central concentration of dust around the solid icy nucleus.

Comet 2I/Borisov is only the second such interstellar object known to have passed through our Solar System. In 2017, the first identified interstellar visitor, an object dubbed ‘Oumuamua, swung within 38 million kilometres of the Sun before racing out of the Solar System. 

“Whereas ‘Oumuamua looked like a bare rock, Borisov is really active, more like a normal comet. It’s a puzzle why these two are so different,” explained David Jewitt of UCLA, leader of the Hubble team who observed the comet. 

** The Space Show – Tue, 10/15/2019 –  Dr. Alan Hale discussed “multiple astronomy, telescope and exoplanet subjects. Also Hale-Bopp and other comets. Alan’s new Ice and Stone 2020 educational outreach project.”

** The Milky Way steals gasses from unidentified neighbors:  Milky Way Raids Intergalactic ‘Bank Accounts,’ Hubble Study Finds | NASA

Our Milky Way is a frugal galaxy. Supernovas and violent stellar winds blow gas out of the galactic disk, but that gas falls back onto the galaxy to form new generations of stars. In an ambitious effort to conduct a full accounting of this recycling process, astronomers were surprised to find a surplus of incoming gas.

“We expected to find the Milky Way’s books balanced, with an equilibrium of gas inflow and outflow, but 10 years of Hubble ultraviolet data has shown there is more coming in than going out,” said astronomer Andrew Fox of the Space Telescope Science Institute, Baltimore, Maryland, lead author of the study to be published in The Astrophysical Journal.

Fox said that, for now, the source of the excess inflowing gas remains a mystery.

Milky Way galaxy's gas recycling
“This illustration envisions the Milky Way galaxy’s gas recycling above and below its stellar disk. Hubble observes the invisible gas clouds rising and falling with its sensitive Cosmic Origins Spectrograph (COS) instrument. The spectroscopic signature of the light from background quasars shining through the clouds gives information about their motion. Quasar light is redshifted in clouds shooting up and away from the galactic plane, while quasar light passing through gas falling back down appears blueshifted. This differentiation allows Hubble to conduct an accurate audit of the outflowing and inflowing gas in the Milky Way’s busy halo — revealing an unexpected and so-far unexplained surplus of inflowing gas. Credits: NASA, ESA and D. Player (STScI)”

The Moon

** Both young and old craters at lunar south pole have water:

The majority of the reported ice deposits are found within large craters formed about 3.1 billion years or longer ago, the study found. Since the ice can’t be any older than the crater, that puts an upper bound on the age of the ice. Just because the crater is old doesn’t mean that the ice within it is also that old too, the researchers say, but in this case there’s reason to believe the ice is indeed old. The deposits have a patchy distribution across crater floors, which suggests that the ice has been battered by micrometeorite impacts and other debris over a long period of time.

If those reported ice deposits are indeed ancient, that could have significant implications in terms of exploration and potential resource utilization, the researchers say.

“There have been models of bombardment through time showing that ice starts to concentrate with depth,” Deutsch said. “So if you have a surface layer that’s old, you’d expect more underneath.”

While the majority of ice was in the ancient craters, the researchers also found evidence for ice in smaller craters that, judging by their sharp, well-defined features, appear to be quite fresh. That suggests that some of the deposits on the south pole got there relatively recently.

“That was a surprise,” Deutsch said. “There hadn’t really been any observations of ice in younger cold traps before.”

** Chandrayaan-2 lunar orbiter begins producing science data: India’s Chandrayaan-2 Moon Probe Just Beamed Back Its 1st Lunar Science | Space.com

The Chandrayaan-2 mission launched in July and was designed to tackle a host of questions about the moon, with a particularly sharp eye to the water ice the spacecraft’s predecessor spotted at the south pole. The current orbiter carries eight different instruments — and Indian scientists are already poring over some of the mission’s very first science data.

The orbiter carries two cameras, both of which have been hard at work. The Terrain Mapping Camera began surveying the moon as soon as Chandrayaan-2 arrived in orbit. Now, the Indian Space Research Organisation (ISRO), which runs the mission, has also released images taken by a second instrument, the Orbiter High Resolution Camera.

Chandrayaan2 Orbiter High Resolution Camera
First images released from the Orbiter High Resolution Camera on the Chandrayaan-2 lunar orbiter. Credits: ISRO

More on Chandrayaan-2 at

The Sun

** The latest on the lack of sunspots: Sunspot update Sept 2019:The blankest Sun in decades – Behind The Black. The latest from Bob Zimmerman on the spotless sun:

With the release yesterday by NOAA of its September update of its graph showing the long term sunspot activity of the Sun, we find ourselves in what might be the longest stretch of sunspot inactivity in decades, part of what might become the most inactive solar minimum in centuries.

In the last four months the Sun has produced practically no sunspots. There were two in June, two in July, and one in August. The September graph, posted below with additional annotations by me to give it context, shows that the past month was as weak as August, with only one sunspot again.

Sunspot vs time in months
A plot of the number of sunspots versus time in months. Credits: Bob Zimmerman

Mars

** More signs of abundant ice on Mars: Ice! Ice! Everywhere on Mars ice! | Behind The Black.  Bob Zimmerman reports on further examples of “exposed ice in a number scarp cliff faces found in the high-mid-latitudes of Mars.

These scarps have so far been found in the highest latitudes of those two glacial bands, which might also explain why they appear more solid with the appearance of only the beginning of degradation. The buried glaciers found in the lower latitudes always look more degraded. As Dundas notes,

We expect that ice at lower latitudes will be less stable because the temperatures are warmer, so on average (over millions of years) at lower latitudes there will be less frequent deposition and more sublimation, so this fits together.

One striking conclusion that we can begin to draw from all this recent research is that ice is likely far more prevalent close to the Martian surface then previously believed. Not only will it be reachable by colonists by simply drilling down to an underground ice table, from 30 degrees latitude and higher there will be numerous places where it will be either close to the surface, or exposed and accessible.

In this image from the Mars Reconnaissance Orbiter (MRO), the blue streak along the edge of a scarf at Milankovic Crater in the northern hemisphere of Mars indicates water ice.  Credits: Bob Zimmerman

** And more Mars surface imagery analysis from Bob Zimmerman at Behind The Black:

** Progress with the Insight lander’s Mole digger: Mars InSight’s ‘Mole’ Is Moving Again | NASA

NASA’s InSight spacecraft has used its robotic arm to help its heat probe, known as “the mole,” dig nearly 2 centimeters (3/4 of an inch) over the past week. While modest, the movement is significant: Designed to dig as much as 16 feet (5 meters) underground to gauge the heat escaping from the planet’s interior, the mole has only managed to partially bury itself since it started hammering in February 2019.

The recent movement is the result of a new strategy, arrived at after extensive testing on Earth, which found that unexpectedly strong soil is holding up the mole’s progress. The mole needs friction from surrounding soil in order to move: Without it, recoil from its self-hammering action will cause it to simply bounce in place. Pressing the scoop on InSight’s robotic arm against the mole, a new technique called “pinning,” appears to provide the probe with the friction it needs to continue digging.

Since Oct. 8, 2019, the mole has hammered 220 times over three separate occasions. Images sent down from the spacecraft’s cameras have shown the mole gradually progressing into the ground. It will take more time — and hammering — for the team to see how far the mole can go.

Insight Mole digs again with help
“‘Pinning’ Helps the Mole Move: This GIF shows NASA InSight’s heat probe, or “mole,” digging about a centimeter (half an inch) below the surface last week. Using a technique called “pinning,” InSight recently pressed the scoop on its robotic arm against the self-hammering mole in order to help it dig. Credit: NASA/JPL-Caltech.”

** Curiosity is staying busy:

Curiosity Mars Rover: Wheel Scuff at Culbin Sands – Leonard David

NASA’s Curiosity Mars rover is now performing Sol 2558 tasks.

The rover has made a wheel scuff at “Culbin Sands,” reports Fred Calef, a planetary geologist at NASA’s Jet Propulsion Laboratory.

Curiosity purposely ran over a megaripple (fine grained sandy ripple with a coarser pebble coating), Calef notes, to create a “scuff” which churned up and bisected the feature to observe any layering or material within.

Curiosity Front Hazard Avoidance-Camera-Left-B-Sol-2557-October-16-2019
Wheel scuff mark made by Curiosity wheel scuff at “Culbin Sands as seen by the Front Hazard Avoidance Camera on-Sol-2557, October-16-2019. Credits: Leonard David

Curiosity Mars Rover: Last Views of Drill Sample, Sand Dancing – Leonard David

Reports Ashley Stroupe, Mission Operations Engineer at NASA’s Jet Propulsion Laboratory, the rover is taking its last views of the Glen Etive 2 drill sample. A recent plan had the robot cleaning out the remaining sample within the drill and doing contact science analysis on the dumped sample.

Both the Chemistry and Camera (ChemCam) and Mastcam will be taking a look at “Penicuik,” a pebble target, and “Monach Isles,” a potential small meteorite. Also planned is a standard environmental observation suite: a Mastcam crater rim extinction and tau, and a Navcam supra-horizon movie.

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Space sciences roundup – Oct.4.2019

A sampling of recent articles, videos, and images from space-related science news items (find previous roundups here):

Astronomy

** Enigmatic radio burst illuminates a galaxy’s tranquil ​halo | ESO

Astronomers using ESO’s Very Large Telescope have for the first time observed that a fast radio burst passed through a galactic halo. Lasting less than a millisecond, this enigmatic blast of cosmic radio waves came through almost undisturbed, suggesting that the halo has surprisingly low density and weak magnetic field. This new technique could be used to explore the elusive halos of other galaxies.

** Hubble Reveals Latest Portrait of Saturn | ESA/Hubble

The NASA/ESA Hubble Space Telescope’s Wide Field Camera 3 observed Saturn on 20 June 2019 as the planet made its closest approach to Earth this year, at approximately 1.36 billion kilometres away.

Since the Hubble Space Telescope was launched, its goal has been to study not only distant astronomical objects, but also the planets within our Solar System. Hubble’s high-resolution images of our planetary neighbours can only be surpassed by pictures taken from spacecraft that actually visit these bodies. However, Hubble has one advantage over space probes; it can look at these objects periodically and observe them over much longer periods than any passing probe could.

 Saturn as seen by Hubble Space Telescope’s Wide Field Camera
Saturn as seen by Hubble Space Telescope’s Wide Field Camera.

** A Cosmic Pretzel | ESO

Astronomers using ALMA have obtained an extremely high-resolution image showing two disks in which young stars are growing, fed by a complex pretzel-shaped network of filaments of gas and dust. Observing this remarkable phenomenon sheds new light on the earliest phases of the lives of stars and helps astronomers determine the conditions in which binary stars are born.

The two baby stars were found in the [BHB2007] 11 system – the youngest member of a small stellar cluster in the Barnard 59 dark nebula, which is part of the clouds of interstellar dust called the Pipe nebula. Previous observations of this binary system showed the outer structure. Now, thanks to the high resolution of the Atacama Large Millimeter/submillimeter Array (ALMA) and an international team of astronomers led by scientists from the Max Planck Institute for Extraterrestrial Physics (MPE) in Germany, we can see the inner structure of this object. 

The Atacama Large Millimeter/submillimeter Array (ALMA) captured this unprecedented image of two circumstellar disks, in which baby stars are growing, feeding with material from their surrounding birth disk. The complex network of dust structures distributed in spiral shapes remind of the loops of a pretzel. These observations shed new light on the earliest phases of the lives of stars and help astronomers determine the conditions in which binary stars are born.

Cosmology

**  If the universe is only 14 billion years old, how can it be 92 billion light years wide? – The light of the most distant stars and galaxies comes from a time not long after the Big Bang. So why didn’t that light pass us back then when we were all “close” together? Here is the explanation:

The size and age of the universe seem to not agree with one another. Astronomers have determined that the universe is nearly 14 billion years old and yet its diameter is 92 billion light years across. How can both of those numbers possibly be true? In this video, Fermilab’s Dr. Don Lincoln tells you how.

Exoplanets

** Hubble Finds Water Vapor on Habitable-Zone Exoplanet for the First Time | ESA/Hubble

With data from the NASA/ESA Hubble Space Telescope, water vapour has been detected in the atmosphere of a super-Earth within the habitable zone by University College London (UCL) researchers in a world first. K2-18b, which is eight times the mass of Earth, is now the only planet orbiting a star outside the Solar System, or exoplanet, known to have both water and temperatures that could support life.

The discovery, published today in Nature Astronomy, is the first successful atmospheric detection of an exoplanet orbiting in its star’s habitable zone, at a distance where water can exist in liquid form.

Asteroids & Comets

** Europe and US teaming up for asteroid deflection – ESA – NASA  will launch the DART (Double Asteroid Redirection Test)  spacecraft in late 2021 to the near-Earth binary asteroid Didymos where it will smack into the smaller of the two objects in Sept. 2022. The goal is to test whether an asteroid on track to impact earth could be diverted from its path. DART will be accompanied by the Italian CubeSat LICIACube (Light Italian CubeSat for Imaging of Asteroids), which will record the impact event .

Another European contribution is the Hera spacecraft, which will launch in 2024. The Hera spacecraft

will perform a close-up survey of the post-impact asteroid, acquiring measurements such as the asteroid’s mass and detailed crater shape. Hera will also deploy a pair of CubeSats for close-up asteroid surveys and the very first radar probe of an asteroid.

The results returned by Hera would allow researchers to better model the efficiency of the collision, to turn this grand-scale experiment into a technique which could be repeated as needed in the event of a real threat.

The combined DART and HERA projects fall under the Asteroid Impact & Deflection Assessment (AIDA) mission.

Astrophysicist and Queen guitarist Brian May describes the HERA mission.

** Visitor from Interstellar SpaceSETI Institute.

Planetary Astronomer Michael Busch and Senior Astronomer Seth Shostak discuss a recent visit from Comet Borisov, C/2019 Q4.

Mars

** NASA’s InSight ‘Hears’ Peculiar Sounds on Mars

NASA’s InSight lander placed a seismometer on the Martian surface to study marsquakes. While it’s found many, it has also detected other kinds of seismic signals, including some produced by the spacecraft itself. That includes wind gusts, InSight’s robotic arm moving around and “dinks and donks,” friction caused by parts inside the seismometer moving against each other as the temperature changes. Put on your headphones and you can hear sonifications of this seismic “noise” recorded on March 6, 2019, the 98th Martian day, or sol, of the mission. Around 2 p.m. local Mars time, the spacecraft’s arm was moving and snapping pictures with its cameras, surveying InSight’s “workspace.” This audio would be too faint for the human ear to heart it on Mars. It’s been sped up by 10 times and processed so you can hear the kinds of signals InSight sends back for its scientists to study.

** NASA InSight’s Robotic Arm Helps Out its Mole on Mars

NASA’s InSight lander on Mars is trying to use its robotic arm to get the mission’s heat flow probe, or mole, digging again. InSight team engineer Ashitey Trebbi-Ollennu, based at NASA’s Jet Propulsion Laboratory in Pasadena, California, explains what has been attempted and the game plan for the coming weeks. The next tactic they’ll try will be “pinning” the mole against the hole it’s in. The German Aerospace Center (DLR) built the mole. It is designed to dig under the Martian surface to measure heat flowing out of the planet. Scientists want this data to learn how Mars and other rocky planets form.

** A recent Curiosity update from Leonard David: Curiosity Mars Rover: “Dumping Dirt on its Back”

NASA’s Curiosity Mars rover has just initiated Sol 2543 duties.

Reports Roger Wiens, Geochemist at Los Alamos National Laboratory in New Mexico: “Curiosity has been at this same location for all of August and September, which included a number of days of waiting for Mars to pass behind the Sun (‘conjunction’), drilling two holes, and processing the samples.”

Curiosity Chemistry and Camera RMI (Remote Micro-Imaging) photo taken on Sol 2541, September 29, 2019. Credit: NASA/JPL-Caltech/LANL

** A selection of Bob Zimmerman‘s analyses of interesting features on the surface of Mars:

Changes in the sand dunes in the Hellas Basin region on Mars in 8 years. Images credit: MRO/HiRISE, NASA JPL/Univ. Arizona. Cropped and annotated by Bob Zimmerman

Webcasts:

** How Do Astronomers Define Latitude & Longitude on Other Planets – Scott Manley:

t took centuries for the people on Earth to decide on a common meridian to measure longitude from, but other planets also need everyone to agree about the origins of their mapping systems. In the case of the terrestrial planets a single bright spot was chosen in the early stages of exploration, and as maps improved the exact location is defined with increasing accuracy. For tidally locked moons the meridian is defined based on orientation relative to the parent body, but even then there’s a lot of room for improvement as data improves. Finally some bodies are just not suited to spherical coordinated, because they’re not particularly spherical.

** Weekly Space Hangout: September 25, 2019 – Seth Lockman & Aaron Lockman: The Astronomy Brothers – YouTube

** All your astronomy questions answered | Space InterviewTMRO.tv

Jared and Tony Darnell from Deep Astronomy lost track of time answering a bunch of community questions ranging from why James Webb Space Telescope is being intentionally launched out of focus, what’s the *next* telescope after JWST gets launched (FINALLY) to why Uranus and Neptune deserve their own dedicated space missions.

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Fire in the Sky:
Cosmic Collisions, Killer Asteroids, and
the Race to Defend Earth

Space sciences roundup – Sept.6.2019

A sampling of recent articles, videos, and images from space-related science news items (find previous roundups here):

[ Update 2: Unfortunately, contact with the Vikram lander was lost shortly before the landing:

Update: Below is the live feed from the Chandrayaan-2 control center. The landing is set for some time between 4:00 and 5:00 pm EDT. The webcast will start around 3:00 EDT.

]

** India’s Chandrayaan-2 mission set for landing on the Moon. The Vikram Lander separated from the orbiter spacecraft on Monday and will touch down on the surface on Friday sometime between 4:00-5:00 pm EDT.

Vikram Lander

The landing area is near the Moon’s south pole. From Space.com:

That spot is a highland that rises between two craters dubbed Manzinus C and Simpelius N. On a grid of the moon’s surface, it would fall at 70.9 degrees south latitude and 22.7 degrees east longitude. It’s about 375 miles (600 kilometers) from the south pole.

The Pragyan rover will be deployed from the lander not long after the landing. The polar regions have craters with permanently shadowed floors and orbital studies indicated they contain water ice.  The extent of the exploration activities will be limited, however. The lander and rover will operate for just one lunar day, which spans 14 earth days. They are not expected to survive the extremely frigid 14 earth day long lunar night.

Pragyan Rover

** China’s lunar rover Yutu-2 comes upon odd substance in a small crater:  China’s Lunar Rover Has Found Something Weird on the Far Side of the Moon | Space.com

The Chang’e 4 lander/rover combo touched down on the far side of the Moon on Jan. 3, 2019 and 12 hours later the rover Yutu-2 was deployed. Since then, the rover has traveled few hundred meters. In late July, Chinese scientists examined images from the rover and noticed an “unusually colored, ‘gel-like’ substance”.

The mission’s rover, Yutu-2, stumbled on that surprise during lunar day 8. The discovery prompted scientists on the mission to postpone other driving plans for the rover, and instead focus its instruments on trying to figure out what the strange material is.

The rover was maneuvered back to the location where the images were taken and the mission team began studies of the material with the rover’s various cameras. So far they have not

… offered any indication as to the nature of the colored substance and have said only that it is “gel-like” and has an “unusual color.” One possible explanation, outside researchers suggested, is that the substance is melt glass created from meteorites striking the surface of the moon.

Crater with Gel-like substance
“Impact crater with mysterious material”. Credits: Yutu No. 2 Driving Diary 6

** Candidate spots on asteroid Bennu selected for OSIRIS-REx  to grab a sampling:  NASA Selects Final Four Site Candidates for Asteroid Sample Return | NASA

After months grappling with the rugged reality of asteroid Bennu’s surface, the team leading NASA’s first asteroid sample return mission has selected four potential sites for the Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer (OSIRIS-REx) spacecraft to “tag” its cosmic dance partner.

Since its arrival in December 2018, the OSIRIS-REx spacecraft has mapped the entire asteroid in order to identify the safest and most accessible spots for the spacecraft to collect a sample. These four sites now will be studied in further detail in order to select the final two sites – a primary and backup – in December.

The team originally had planned to choose the final two sites by this point in the mission. Initial analysis of Earth-based observations suggested the asteroid’s surface likely contains large “ponds” of fine-grain material. The spacecraft’s earliest images, however, revealed Bennu has an especially rocky terrain. Since then, the asteroid’s boulder-filled topography has created a challenge for the team to identify safe areas containing sampleable material, which must be fine enough – less than 1 inch (2.5 cm) diameter – for the spacecraft’s sampling mechanism to ingest it.

OSIRIS REx sample site candidates
Pictured are the four candidate sample collection sites on asteroid Bennu selected by NASA’s OSIRIS-REx mission. Site Nightingale (top left) is located in Bennu’s northern hemisphere. Sites Kingfisher (top right) and Osprey (bottom left) are located in Bennu’s equatorial region. Site Sandpiper (bottom right) is located in Bennu’s southern hemisphere. In December, one of these sites will be chosen for the mission’s touchdown event. Credits: NASA/University of Arizona”

** An overview of the missions – past, present, and future – to the small objects in our solar system:  Asteroids, comets and moons – ESA

We have learned a lot from visiting the Moon, and even more from visiting other planets, but what about the thousands of other small objects that share our Solar System? Space agencies have sent several spacecraft to asteroids, comets, dwarf planets and small moons, and have ambitious plans to send more in the future.

Asteroids and comets are believed to be leftover debris from the formation of the Solar System, meaning they can help trace its history. What’s more, these objects may have played a vital role in the development of our planet and terrestrial life by colliding with Earth in catastrophic impact events, bringing life-sparking organic compounds. Such collisions were more common in the early Solar System, but small objects can still impact Earth, damaging life, nature and infrastructure.

Such objects may also have brought organic matter to other planets and moons, some of which – Jupiter’s moon Europa or Saturn’s moon Enceladus, for example – may possess the right conditions for hosting some form of life. For all these reasons, and many more, it is important to study these objects and find out more about them.

** An update on the exoplanet search with the TESS space observatory:

A discussion between NASA researcher Jon Jenkins & SETI Institute Astronomer Franck Marchis about TESS spacecraft and its recent discoveries.

** A beautiful view of Jupiter from Hubble:  Hubble Showcases New Portrait of Jupiter | ESA/Hubble

The NASA/ESA Hubble Space Telescope reveals the intricate, detailed beauty of Jupiter’s clouds in this new image taken on 27 June 2019[1]. It features the planet’s trademark Great Red Spot and a more intense colour palette in the clouds swirling in the planet’s turbulent atmosphere than seen in previous years.

Among the most striking features in the image are the rich colours of the clouds moving toward the Great Red Spot. This huge anticyclonic storm is roughly the diameter of Earth and is rolling counterclockwise between two bands of clouds that are moving in opposite directions toward it. 

As with previous images of Jupiter taken by Hubble, and other observations from telescopes on the ground, the new image confirms that the huge storm which has raged on Jupiter’s surface for at least 150 years continues to shrink. The reason for this is still unknown so Hubble will continue to observe Jupiter in the hope that scientists will be able to solve this stormy riddle. Much smaller storms appear on Jupiter as white or brown ovals that can last as little as a few hours or stretch on for centuries. 

Jupiter’s Colourful Palette
The NASA/ESA Hubble Space Telescope reveals the intricate, detailed beauty of Jupiter’s clouds in this new image taken on 27 June 2019 by Hubble’s Wide Field Camera 3, when the planet was 644 million kilometres from Earth — its closest distance this year. The image features the planet’s trademark Great Red Spot and a more intense colour palette in the clouds swirling in the planet’s turbulent atmosphere than seen in previous years. The observations of Jupiter form part of the Outer Planet Atmospheres Legacy (OPAL) programme.

** The VLT Survey Telescope (VST) captures a magnificent stellar bird: Anatomy of a Cosmic Seagull | ESO

Colourful and wispy Sharpless 2-296 forms the “wings” of an area of sky known as the Seagull Nebula — named for its resemblance to a gull in flight. This celestial bird contains a fascinating mix of intriguing astronomical objects. Glowing clouds weave amid dark dust lanes and bright stars. The Seagull Nebula — made up of dust, hydrogen, helium and traces of heavier elements — is the hot and energetic birthplace of new stars.

** Parker Solar Probe completes two orbits around the sun since launch in August of 2018: One Year, 2 Trips Around Sun for NASA’s Parker Solar Probe | NASA

In the year since launch, Parker Solar Probe has collected a host of scientific data from two close passes by the Sun.

“We’re very happy,” said Nicky Fox, director of NASA’s Heliophysics Division at NASA Headquarters in Washington, D.C. “We’ve managed to bring down at least twice as much data as we originally suspected we’d get from those first two perihelion passes.”

The spacecraft carries four suites of scientific instruments to gather data on the particles, solar wind plasma, electric and magnetic fields, solar radio emission, and structures in the Sun’s hot outer atmosphere, the corona. This information will help scientists unravel the physics driving the extreme temperatures in the corona — which is counter intuitively hotter than the solar surface below — and the mechanisms that drive particles and plasma out into the solar system.

Follow the solar mission via:

** Mars

*** Mars Curiosity Rover continues on a trail of discoveries after 7 years on Mars:  New Finds for Mars Rover, Seven Years After Landing | NASA

NASA’s Curiosity rover has come a long way since touching down on Mars seven years ago. It has traveled a total of 13 miles (21 kilometers) and ascended 1,207 feet (368 meters) to its current location. Along the way, Curiosity discovered Mars had the conditions to support microbial life in the ancient past, among other things.

And the rover is far from done, having just drilled its 22nd sample from the Martian surface. It has a few more years before its nuclear power system degrades enough to significantly limit operations. After that, careful budgeting of its power will allow the rover to keep studying the Red Planet.

Curiosity is now halfway through a region scientists call the “clay-bearing unit” on the side of Mount Sharp, inside of Gale Crater. Billions of years ago, there were streams and lakes within the crater. Water altered the sediment deposited within the lakes, leaving behind lots of clay minerals in the region. That clay signal was first detected from space by NASA’s Mars Reconnaissance Orbiter (MRO) a few years before Curiosity launched.

Check out this 360 degree view of Mars:

Curiosity captured this 360-degree panorama of a location on Mars called “Teal Ridge” on June 18, 2019. This location is part of a larger region the rover has been exploring called the “clay-bearing unit” on the side of Mount Sharp, which is inside Gale Crater. The scene is presented with a color adjustment that approximates white balancing to resemble how the rocks and sand would appear under daytime lighting conditions on Earth. Scientists are looking for signs that Mars could have supported microbial life billions of years ago, when rivers and lakes could be found in the crater.

*** Where Curiosity has been and where its going: Mid-2019 Map of NASA’s Curiosity Rover Mission – NASA JPL

This map shows the route driven by NASA’s Curiosity Mars rover, from the location where it landed in August 2012 to its location in August 2019, and its planned path to additional geological layers of lower “Mount Sharp.” The blue star near top center marks “Bradbury Landing,” the site where Curiosity arrived on Mars on Aug. 5, 2012, PDT (Aug. 6, EDT and Universal Time). Curiosity landed on Aeolis Palus, the plains surrounding Aeolis Mons (Mount Sharp) in Gale Crater.

Mid-2019 Map of NASA's Curiosity Rover MissionMore about the planned route for the rover from Bob Zimmerman: Curiosity’s future travels | Behind The Black.

*** And more reports from Bob on images of interesting features on Mars as seen by the orbiters:

*** Bob was also the first to see the locations that SpaceX is examining for potential landings of Starships in the coming decade:

*** The Mars 2020 mission will deploy a drone for the first time. The Mars Helicopter was recently installed onto the rover:

Engineers at NASA’s Jet Propulsion Laboratory in California have attached a flying helicopter drone to the belly of the Mars 2020 rover set for launch next July.

The solar-powered Mars Helicopter stands about 2.6 feet (80 centimeters) tall when fully deployed, and will become the first aircraft to fly on another planet. The robot drone will ride to the Red Planet with NASA’s Mars 2020 rover, which has been assembled at JPL to begin testing in the coming weeks.

The Mars 2020 mission is scheduled for launch from Cape Canaveral on July 17, 2020, the first day of a nearly three-week window for the rover to depart Earth and head for Mars. The rover will blast off atop a United Launch Alliance Atlas 5 rocket.

The rover will land at Jezero Crater on Feb. 18, 2021.

NASA’s Mars Helicopter, a small, autonomous rotorcraft, will travel with the agency’s Mars 2020 rover to demonstrate the viability and potential of heavier-than-air vehicles on the Red Planet. Credits: NASA/JPL-Caltech

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Fire in the Sky:
Cosmic Collisions, Killer Asteroids, and
the Race to Defend Earth

Space sciences roundup – Aug.1.2019

A sampling of recent articles, videos, and images from space-related science news items:

** Comets & Asteroids

*** the Comet is a terrific short film created by Christian Stangl who used a good fraction of the thousands of images taken by ESA’s Rosetta mission of the comet Churyumov-Gerasimenko (67p). The music for the soundtrack was composed by Wolfgang Stangl.

*** A sizable  asteroid, previously unknown, flew quite close to earth on July 25th:

From WP:

This asteroid wasn’t one that scientists had long been tracking, and it had seemingly appeared from “out of nowhere,” Michael Brown, a Melbourne-based observational astronomer, told The Washington Post. According to data from NASA, the craggy rock was large, an estimated 57 to 130 meters wide (187 to 427 feet), and moving fast along a path that brought it within about 73,000 kilometers (45,000 miles) of Earth. That’s less than one-fifth of the distance to the moon and what Duffy considers “uncomfortably close.”

Not a country destroyer but it could damage a city if it reached close to the ground:

In 2013, a significantly smaller meteor — about 20 meters (65 feet) across, or the size of a six-story building — broke up over the Russian city of Chelyabinsk and unleashed an intense shock wave that collapsed roofs, shattered windows and left about 1,200 people injured. The last space rock to strike Earth similar in size to Asteroid 2019 OK was more than a century ago, Brown said. That asteroid, known as the Tunguska event, caused an explosion that leveled 2,000 square kilometers (770 square miles) of forest land in Siberia.

*** A flash spotted by weather-sat correlated with a small asteroid detected earlier by a NEO tracking network – NASA Tracked Small Asteroid Before It Broke Up in Atmosphere – NASA JPL

When a lightning detector on a NOAA weather satellite detected something that wasn’t lightning last Saturday, a scientist at the Center for Near Earth Object Studies at NASA’s Jet Propulsion Laboratory in Pasadena, California, did some detective work.

Could a tiny, harmless object that broke up in the atmosphere in a bright flash be connected to a just-received automated alert of a potential near-Earth asteroid discovery? Although far below the size that NASA is tasked to detect and track, the event presented an ideal opportunity for NASA planetary defense teams to test their parts of the alert system.

The outcome? The flow of alert data works, and the culprit was identified: It was an asteroid. Now designated 2019 MO, the asteroid was only about 16 feet (5 meters) in size and was detected at 9:45 UTC (2:45 a.m. PDT, 5:45 a.m. EDT) on Saturday, June 22, by the University of Hawaii’s ATLAS survey telescope on Maunaloa in Hawaii.

** Exoplanets

*** TESS exoplanet observatory off to a good start in its first year in space: TESS Completes 1st Year of Exoplanet Survey, Turns to Northern Sky | NASA

NASA’s Transiting Exoplanet Survey Satellite (TESS) has discovered 21 planets outside our solar system and captured data on other interesting events occurring in the southern sky during its first year of science. TESS has now turned its attention to the Northern Hemisphere to complete the most comprehensive planet-hunting expedition ever undertaken.

TESS began hunting for exoplanets (or worlds orbiting distant stars) in the southern sky in July of 2018, while also collecting data on supernovae, black holes and other phenomena in its line of sight. Along with the planets TESS has discovered, the mission has identified over 850 candidate exoplanets that are waiting for confirmation by ground-based telescopes.

*** TESS spots 3 exoplanets on the small end of the mass spectrum. One is a rocky world a bit bigger than the earth while the other two are about twice as big as earth and classified as gaseous “Mini-Neptunes”. All are in orbits very close to their star: NASA’s TESS Mission Scores ‘Hat Trick’ With 3 New Worlds | NASA

NASA’s newest planet hunter, the Transiting Exoplanet Survey Satellite (TESS), has discovered three new worlds — one slightly larger than Earth and two of a type not found in our solar system — orbiting a nearby star. The planets straddle an observed gap in the sizes of known planets and promise to be among the most curious targets for future studies.

TESS Object of Interest (TOI) 270 is a faint, cool star more commonly identified by its catalog name: UCAC4 191-004642. The M-type dwarf star is about 40% smaller than the Sun in both size and mass, and it has a surface temperature about one-third cooler than the Sun’s. The planetary system lies about 73 light-years away in the southern constellation of Pictor.

 TOI 270 system
This infographic illustrates key features of the TOI 270 system, located about 73 light-years away in the southern constellation Pictor. The three known planets were discovered by NASA’s Transiting Exoplanet Survey Satellite through periodic dips in starlight caused by each orbiting world. Insets show information about the planets, including their relative sizes, and how they compare to Earth. Temperatures given for TOI 270’s planets are equilibrium temperatures, calculated without the warming effects of any possible atmospheres. Credits: NASA’s Goddard Space Flight Center/Scott Wiessinger”. Find more TESS TOI 270 graphics here.

*** TESS found 3 planets in another system and one of the planets is in the star system’s habitable zone : NASA’s TESS Helps Find Intriguing New World | NASA

Tour the GJ 357 system, located 31 light-years away in the constellation Hydra. Astronomers confirming a planet candidate identified by NASA’s Transiting Exoplanet Survey Satellite subsequently found two additional worlds orbiting the star. The outermost planet, GJ 357 d, is especially intriguing to scientists because it receives as much energy from its star as Mars does from the Sun.

“GJ 357 d is located within the outer edge of its star’s habitable zone, where it receives about the same amount of stellar energy from its star as Mars does from the Sun,” said co-author Diana Kossakowski at the Max Planck Institute for Astronomy in Heidelberg, Germany. “If the planet has a dense atmosphere, which will take future studies to determine, it could trap enough heat to warm the planet and allow liquid water on its surface.”

Without an atmosphere, it has an equilibrium temperature of -64 F (-53 C), which would make the planet seem more glacial than habitable. The planet weighs at least 6.1 times Earth’s mass, and orbits the star every 55.7 days at a range about 20% of Earth’s distance from the Sun. The planet’s size and composition are unknown, but a rocky world with this mass would range from about one to two times Earth’s size.

** The Moon

*** Lunar science since Apollo 11 : Astronomer Andrew Fraknoi: 50 Years Since Our First Step held on July 17, 2019 _ Commonwealth Club

July 20, 2019 is the 50th anniversary of humanity’s first steps on the surface of the moon. In that time, the Apollo missions, a fleet of robotic probes and observations from Earth have taught us a lot about Earth’s surprising satellite. In this nontechnical talk, Andrew Fraknoi, who is sometimes called the Bay Area’s public astronomer, will look at the past, present and future of the moon, including its violent origins, the mystery of the frozen water we have found at its poles and its long-term future as it moves farther and farther away from us. Illustrated with beautiful images taken from orbit and on the surface, his talk will make the moon come alive as an eerie world next door, as a changing object in our skies, and as a possible future destination for humanity and its ambitions. Come find out how the achievements of the Apollo program fit into the bigger picture of our involvement with our only natural satellite.

See also: Andrew Fraknoi: Exploring the Universe: My Talk to the Commonwealth Club on the Moon

*** Permanently dark floors of lunar polar craters are quite dynamic according to latest findings: In Dark, Polar Moon Craters, Water Not Invincible, Scientists Argue | NASA

Unlike Earth, with its plush atmosphere, the Moon has no atmosphere to protect its surface. So when the Sun sprays charged particles known as the solar wind into the solar system, some of them bombard the Moon’s surface and kick up water molecules that bounce around to new locations.

Likewise, wayward meteoroids constantly smash into the surface and uproot soil mingled with frozen bits of water. Meteoroids can hurtle these soil particles — which are many times smaller than the width of a human hair — as far as 19 miles (30 kilometers) away from the impact site, depending on the size of the meteoroid. The particles can travel so far because the Moon has low gravity and no air to slow things down: “So every time you have one of these impacts, a very thin layer of ice grains is spread across the surface, exposed to the heat of the Sun and to the space environment, and eventually sublimated or lost to other environmental processes,” said Dana Hurley, a planetary scientist at the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland.

While it’s important to consider that even in the shadowed craters water is slowly seeping out, it’s possible that water is being added, too, the paper authors note. Icy comets that crash into the Moon, plus the solar wind, could be replenishing it as part of a global water cycle; that’s something scientists are trying to figure out. Additionally, it’s not clear how much water there is. Is it sitting only in the top layer of the Moon’s surface or does it extend deep into the Moon’s crust, scientists wonder?

Either way, the topmost layer of polar crater floors is getting reworked over thousands of years, according to calculations by Farrell, Hurley, and their team. Therefore, the faint patches of frost that scientists have detected at the poles using instruments such as LRO’s Lyman Alpha Mapping Project (LAMP) instrument could be just 2,000 years old, instead of millions or billions of years old as some might expect, Farrell’s team estimated. “We can’t think of these craters as icy dead spots,” he noted.

*** Big boulders leave trails on side of Antoniadi crater on the Moon’s far side:

The most prominent trail shows the boulder coming to a halt near a small crater:

Had it rolled just 75 meters more, the boulder might have plopped neatly into a 30-meter-diameter young impact crater on the floor of the partially erased crater. As Apollo 14 golfer Alan Shepard might have expressed it: the boulder narrowly missed scoring a hole-in-one.

Boulder trail in Antoniadi crater
This LRO image shows the trail of a boulder “bigger than a bus” on the side of the Antoniadi crater on the Moon’s far side. Credits: NASA/GSFC/Arizona State University.

Bob Zimmerman notices also

… two more less obvious boulder tracks. If you click on the full resolution image and zoom in you can also see another series of impressions in the middle of the photograph that look like a dotted line, suggesting they were left by a boulder bouncing down the slope.

The scattered of boulders in the floor of the small crater all likely came from the top of the big crater’s rim, …

** Mars:

*** Testing Mars 2020 rover’s robotic arm: NASA’s Mars 2020 Rover Does Biceps Curls – NASA JPL

Time lapse video of robotic arm on NASA’s Mars 2020 rover handily maneuvers 88-pounds (40 kilograms) worth of sensor-laden turret as it moves from a deployed to stowed configuration. For more information about the turret and the Mars 2020 mission, visit https://mars.nasa.gov/mars2020

The rover is also getting charged up with its nuclear fuel: Fueling of NASA’s Mars 2020 Rover Power System Begins – NASA JPL

*** An update on Curiosity‘s travels and explorations: Curiosity Mars Rover Cracks 13 Miles, New Drill Site in Sight – Leonard David

[NASA JPL planetary geologist Vivian Sun] adds that there were no bedrock exposures available for contact science activities in Curiosity’s immediate workspace, so attention has now shifted to identify a drill site area, with the rover driving to that spot.

Check out this cool map showing Curiosity’s route since it landed on August 5, 2012:

Curiosity has now driven 13.10 miles (21.08 kilometers) since landing on Mars in August 2012.

A newly released Curiosity traverse map through Sol 2480 shows the route driven by the robot through the 2480 Martian day, or sol.

MSL Traverse Map as of Sol 2480
Map of Curiosity’s movements as of Sol 2480. Credit: NASA/JPL-Caltech/Univ. of Arizona. Click for larger image.

See also Curiosity Mission Updates – NASA Mars.

*** Strong evidence of water glaciers beneath the surface in many areas of Mars: The glaciers of Mars | Behind The Black

For the future colonists of Mars, the question of finding water will not be that much of a problem. Not only have planetary geologists mapped out the existence of extensive water-ice in the Martian poles, they have found that the planet apparently has widespread glacier deposits in two mid-latitude belts from 30 to 60 degrees latitude.

The question will be whether those Martian settlers will be able to easily access this water. The data so far suggests that much of the Martian underground water at high latitudes is likely mixed with dust and debris. Extracting it might not be straightforward. There are hints that the ice table at latitudes about 55 degrees might be more pure, but could be somewhat deep below ground, requiring the settlers to become miners to obtain their water. Moreover, all these high latitude locations are in environments that are more hostile, and therefore more difficult to establish a colony.

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Fire in the Sky:
Cosmic Collisions, Killer Asteroids,
and the Race to Defend Earth