Category Archives: Astronomy

Astronomy, Gas giants Saturn, Jupiter, et al, Mars, The Moon

Space science roundup – Feb.21.2019

February 21, 2019 TopSpacer

A sampling of recent articles, videos, and images related to space related sciences:

** Mars weather reports – Daily Mars weather reports are now available from the Insight lander, which has activated its temperature and wind sensors – InSight Is the Newest Mars Weather Service | NASA

This public tool includes stats on temperature, wind and air pressure recorded by InSight. Sunday’s weather was typical for the lander’s location during late northern winter: a high of 2 degrees Fahrenheit (-17 degrees Celsius) and low of -138 degrees Fahrenheit (-95 degrees Celsius), with a top wind speed of 37.8 mph (16.9 m/s) in a southwest direction. The tool was developed by NASA’s Jet Propulsion Laboratory in Pasadena, California, with partners at Cornell University and Spain’s Centro de Astrobiología. JPL leads the InSight mission.

The white east- and west-facing booms — called Temperature and Wind for InSight, or TWINS — on the deck of NASA’s InSight lander belong to its suite of weather sensors. Credits: NASA/JPL-Caltech. Full image and caption

Through a package of sensors called the Auxiliary Payload Subsystem (APSS), InSight will provide more around-the-clock weather information than any previous mission to the Martian surface. The lander records this data during each second of every sol (a Martian day) and sends it to Earth on a daily basis. The spacecraft is designed to continue that operation for at least the next two Earth years, allowing it to study seasonal changes as well.

The tool will be geeky fun for meteorologists while offering everyone who uses it a chance to be transported to another planet.

Today’s readings:

A similar weather report is available from the Curiosity rover: Rover Environmental Monitoring Station (REMS) – Mars Science Laboratory.

The Mars Reconnaissance Orbiter (MRO) provides a view of global Martian atmosphere conditions: MRO MARCI Weather Report – Malin Space Science Systems.

** The Mars 2020 rover is coming together at NASA JPL in preparation for launch next year:

Tour the Spacecraft Assembly Facility at NASA’s Jet Propulsion Laboratory and see the Mars 2020 mission under construction. Project System Engineer Jennifer Trosper explains the hardware being built and tested, including the rover, descent stage, cruise stage, back shell and heat shield. This NASA mission is preparing to launch to the Red Planet in 2020 and land in 2012. For more about Mars 2020, visit https://mars.nasa.gov/m2020

** Rovers on Mars and the Moon: Bob Zimmerman gives an update on Curiosity as it slowly ascends Mt Sharp and on China’s Yutu-2 rover on the lunar surface: Rover update: February 20, 2019 | Behind The Black

The valley that Curiosity is presently traversing is dubbed “the clay unit” or “the clay-bearing unit” by the geologists, based on its make-up determined from orbital data. So far they have found this terrain to be “some of the best driving terrain we’ve encountered in Gale Crater, with just some occasional sandy patches in the lee of small ridges.” Initially they had problems finding any rocks or pebbles large enough for the instruments to use for gathering geological data. For the past week or so, however, they have stopped at “bright exposure of rock” where some bedrock was visible, giving them much better material to work with.

*Click to see Curiosity’s track for past couple of years.*

** Mars once had rivers flowing on its surface as shown by river beds seen from orbit. But up close images of the river beds show that it has been billions of years since water flowed over them: A river valley floor on Mars | Behind The Black

*The floor of a canyon in Reull Vallis.*

Here we see that the floor has been significantly eroded by later processes after the water disappeared. Later, wind action, which probably contributed to that erosion, also placed dust and dunes within the depressions here.

A lot of time has passed since that river flowed through Reull Valles. Or to put it another way, Mars has generally been a very dry place for a very long time. It might have considerable water at its poles as well hidden in an underground ice aquifer, but its surface is far drier than any desert on Earth, and has been for eons.

** Odd looking surface features on Mars are not uncommon. Here Bob examines an unusual pit that he spotted in an image of the south pole: Strange crescent-shaped pit near Martian south pole | Behind The Black –

I found it in the February image release from the high resolution camera on Mars Reconnaissance Orbiter. I have merely cropped the full image to focus at full resolution on its primary feature, a region of stippled-like surface surrounding an area of black striping that in turn surrounds a crescent-shaped pit outlined by whiter material.

Why is there a pit here? Why is it crescent-shaped? Why is it surrounded by that whiter material? I could guess and say that the pit is a vent from which water vapor from the lower cap of water sprays out onto the upper cap of frozen carbon dioxide, staining it with white ice, but I am most likely wrong.

Moreover, what causes the black striping, as well as the stippled material surrounding it? The black stripes are probably related to a similar process that forms the spider formations found in the polar regions, except that these are not spiders. Why the parallel straight lines?

** The Chinese Chang’e 4 lander & rover on the far side of the Moon are currently in hibernation during the 2 week long lunar night. The Lunar Reconnaissance Orbiter has posted images of the pair taken during a pass over its location:

On 30 January LROC acquired a spectacular limb shot centered on the Chang’e 4 landing site, looking across the floor of Von Kármán crater. At the time, LRO was more than 200 kilometers from the landing site so Chang’e 4 was only a few pixels across and the rover was not discernable. The following day LRO was closer to the site and again slewed (59° this time) to capture another view. This time the small Yutu-2 rover shows up (two pixels) just north of the lander. Also, shadows cast by the lander and rover are now visible.

“The Chang’e 4 rover is now visible to LROC! Just beyond the tip of the right arrow is the rover and the lander is to the right of the tip of the left arrow. The image appears blocky because it is enlarged 4x to make it easier to see the two vehicles. North is to the upper right, LROC NAC M1303570617LR [NASA/GSFC/Arizona State University].”

The official Chinese lunar exploration website doesn’t appear to offer an English version but your can always use the Google translation.

** Fly around Jupiter – Here is a cool time-lapse of images from the Juno probe as it made its 17th close pass above Jupiter’s clouds: ‘Juno’s Perijove-17 Jupiter Flyby, Reconstructed in 125-Fold Time-Lapse’ | JunoCam : Processing | Mission Juno

Via Movie of Juno’s December 2018 Jupiter fly-by | Behind The Black.

** A Neptune moon is a chip off the old Proteus moon according to a new report based on Hubble telescope imaging: Tiny Neptune Moon Spotted by Hubble May Have Broken from Larger Moon | NASA

Astronomers call it “the moon that shouldn’t be there.”

After several years of analysis, a team of planetary scientists using NASA’s Hubble Space Telescope has at last come up with an explanation for a mysterious moon around Neptune that they discovered with Hubble in 2013.

The tiny moon, named Hippocamp, is unusually close to a much larger Neptunian moon called Proteus. Normally, a moon like Proteus should have gravitationally swept aside or swallowed the smaller moon while clearing out its orbital path.

So why does the tiny moon exist? Hippocamp is likely a chipped-off piece of the larger moon that resulted from a collision with a comet billions of years ago. The diminutive moon, only 20 miles (about 34 kilometers) across, is 1/1000th the mass of Proteus (which is 260 miles [about 418 kilometers] across).

** The Moon receives a constant shower of solar protons, which can interact with oxygen in surface rocks with oxygen-bearing molecules to produce hydroxyl (OH), which needs just one more proton to become water (H2O): NASA Finds Moon Could Be a Chemical Factory for Water | NASA

When a stream of charged particles known as the solar wind careens onto the Moon’s surface at 450 kilometers per second (or nearly 1 million miles per hour), they enrich the Moon’s surface in ingredients that could make water, NASA scientists have found.

Using a computer program, scientists simulated the chemistry that unfolds when the solar wind pelts the Moon’s surface. As the Sun streams protons to the Moon, they found, those particles interact with electrons in the lunar surface, making hydrogen (H) atoms. These atoms then migrate through the surface and latch onto the abundant oxygen (O) atoms bound in the silica (SiO₂) and other oxygen-bearing molecules that make up the lunar soil, or regolith. Together, hydrogen and oxygen make the molecule hydroxyl (OH), a component of water, or H₂O.

“We think of water as this special, magical compound,” said William M. Farrell, a plasma physicist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, who helped develop the simulation. “But here’s what’s amazing: every rock has the potential to make water, especially after being irradiated by the solar wind.”

This has implications for lunar settlers:

A key ramification of the result, [NASA Goddard plasma physicist William M. Farrell] said, is that every exposed body of silica in space — from the Moon down to a small dust grain — has the potential to create hydroxyl and thus become a chemical factory for water.

** Dark matters – On a recent episode of The Space Show (Fri, 02/15/2019), Dr. William Dawson of Lawrence Livermore National Laboratory (LLNL) discussed “dark matter, dark energy, physics research, black holes, research goals and legacy, gravitational waves, gravitational lensing and much more”.

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Chasing New Horizons: Inside the Epic First Mission to Pluto

Astronomy, Space participation

Citizen Scientist in NASA project spots ancient white dwarf star with puzzling rings

February 20, 2019 TopSpacer

As often reported here, citizen scientists, especially in astronomy, continue to make significant contributions to the sciences. Here is a new article from NASA detailing one such case:

Citizen Scientist Finds Ancient White Dwarf Star With Puzzling Rings

A volunteer working with the NASA-led Backyard Worlds: Planet 9 project has found the oldest and coldest known white dwarf — an Earth-sized remnant of a Sun-like star that has died — ringed by dust and debris. Astronomers suspect this could be the first known white dwarf with multiple dust rings.

In this illustration, an asteroid (bottom left) breaks apart under the powerful gravity of LSPM J0207+3331, the oldest, coldest white dwarf known to be surrounded by a ring of dusty debris. Scientists think the system’s infrared signal is best explained by two distinct rings composed of dust supplied by crumbling asteroids. Credits: NASA’s Goddard Space Flight Center/Scott Wiessinger. *Download in high-resolution formats from NASA Goddard’s Scientific Visualization Studio*

The star, LSPM J0207+3331 or J0207 for short, is forcing researchers to reconsider models of planetary systems and could help us learn about the distant future of our solar system.

“This white dwarf is so old that whatever process is feeding material into its rings must operate on billion-year timescales,” said John Debes, an astronomer at the Space Telescope Science Institute in Baltimore. “Most of the models scientists have created to explain rings around white dwarfs only work well up to around 100 million years, so this star is really challenging our assumptions of how planetary systems evolve.”

A paper detailing the findings, led by Debes, was published in the Feb. 19 issue of The Astrophysical Journal Letters and is now available online.

J0207 is located around 145 light-years away in the constellation Capricornus. White dwarfs slowly cool as they age, and Debes’ team calculated J0207 is about 3 billion years old based on a temperature just over 10,500 degrees Fahrenheit (5,800 degrees Celsius). A strong infrared signal picked up by NASA’s Wide-field Infrared Survey Explorer (WISE) mission — which mapped the entire sky in infrared light — suggested the presence of dust, making J0207 the oldest and coldest white dwarf with dust yet known. Previously, dust disks and rings had only been observed surrounding white dwarfs about one-third J0207’s age.

When a Sun-like star runs out of fuel, it swells into a red giant, ejects at least half of its mass, and leaves behind a very hot white dwarf. Over the course of the star’s giant phase, planets and asteroids close to the star become engulfed and incinerated. Planets and asteroids farther away survive, but move outward as their orbits expand. That’s because when the star loses mass, its gravitational influence on surrounding objects is greatly reduced.

This scenario describes the future of our solar system. Around 5 billion years from now, Mercury, then Venus and possibly Earth will be swallowed when the Sun grows into a red giant. Over hundreds of thousands to millions of years, the inner solar system will be scrubbed clean, and the remaining planets will drift outward.

Citizen scientists working on Backyard Worlds: Planet 9 scrutinize “flipbooks” of images from NASA’s Wide-field Infrared Survey Explorer. This animation shows a flipbook containing the ring-bearing white dwarf LSPM J0207+3331 (circled).
*Credit: Backyard Worlds: Planet 9/NASA’s Goddard Space Flight Center*

Yet some white dwarfs — between 1 and 4 percent — show infrared emission indicating they’re surrounded by dusty disks or rings. Scientists think the dust may arise from distant asteroids and comets kicked closer to the star by gravitational interactions with displaced planets. As these small bodies approach the white dwarf, the star’s strong gravity tears them apart in a process called tidal disruption. The debris forms a ring of dust that will slowly spiral down onto the surface of the star.

J0207 was found through Backyard Worlds: Planet 9, a project led by Marc Kuchner, a co-author and astrophysicist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, that asks volunteers to sort through WISE data for new discoveries.

Melina Thévenot, a co-author and citizen scientist in Germany working with the project, initially thought the infrared signal was bad data. She was searching through the ESA’s (European Space Agency’s) Gaia archives for brown dwarfs, objects too large to be planets and too small to be stars, when she noticed J0207. When she looked at the source in the WISE infrared data, it was too bright and too far away to be a brown dwarf. Thévenot passed her findings along to the Backyard Worlds: Planet 9 team. Debes and Kuchner contacted collaborator Adam Burgasser at the University of California, San Diego to obtain follow-up observations with the Keck II telescope at the W. M. Keck Observatory in Hawaii.

“That is a really motivating aspect of the search,” said Thévenot, one of more than 150,000 citizen scientists on the Backyard Worlds project. “The researchers will move their telescopes to look at worlds you have discovered. What I especially enjoy, though, is the interaction with the awesome research team. Everyone is very kind, and they are always trying to make the best out of our discoveries.”

The Keck observations helped confirm J0207’s record-setting properties. Now scientists are left to puzzle how it fits into their models.

Debes compared the population of asteroid belt analogs in white dwarf systems to the grains of sand in an hourglass. Initially, there’s a steady stream of material. The planets fling asteroids inward towards the white dwarf to be torn apart, maintaining a dusty disk. But over time, the asteroid belts become depleted, just like grains of sand in the hourglass. Eventually, all the material in the disk falls down onto the surface of the white dwarf, so older white dwarfs like J0207 should be less likely to have disks or rings.

J0207’s ring may even be multiple rings. Debes and his colleagues suggest there could be two distinct components, one thin ring just at the point where the star’s tides break up the asteroids and a wider ring closer to the white dwarf. Follow-up with future missions like NASA’s James Webb Space Telescope may help astronomers tease apart the ring’s constituent parts.

“We built Backyard Worlds: Planet 9 mostly to search for brown dwarfs and new planets in the solar system,” Kuchner said. “But working with citizen scientists always leads to surprises. They are voracious — the project just celebrated its second birthday, and they’ve already discovered more than 1,000 likely brown dwarfs. Now that we’ve rebooted the website with double the amount of WISE data, we’re looking forward to even more exciting discoveries.”

Backyard Worlds: Planet 9 is a collaboration between NASA, the American Museum of Natural History in New York, Arizona State University, National Optical Astronomy Observatory, the Space Telescope Science Institute in Baltimore, the University of California San Diego, Bucknell University, the University of Oklahoma, and Zooniverse, a collaboration of scientists, software developers and educators who collectively develop and manage citizen science projects on the internet.

NASA’s Jet Propulsion Laboratory in Pasadena, California, manages and operates WISE for NASA’s Science Mission Directorate. The WISE mission was selected competitively under NASA’s Explorers Program managed by the agency’s Goddard Space Flight Center. The science instrument was built by the Space Dynamics Laboratory in Logan, Utah. The spacecraft was built by Ball Aerospace & Technologies Corp. in Boulder, Colorado. Placed in hibernation in 2011, the spacecraft was reactivated in 2013 and renamed NEOWISE. Science operations and data processing take place at the Infrared Processing and Analysis Center at Caltech, which manages JPL for NASA.

For more information about Backyard Worlds: Planet 9, visit: http://backyardworlds.org

For more information about NASA’s WISE mission, visit: http://www.nasa.gov/wise

By Jeanette Kazmierczak
NASA’s Goddard Space Flight Center, Greenbelt, Md.

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Telescopes and Binoculars at Amazon

Astronomy

ESO: Region of new star formation spotted in Large Magellanic Cloud

February 6, 2019 TopSpacer

The latest report from ESO (European Southern Observatory):

Bubbles of Brand New Stars

This dazzling region of newly-forming stars in the Large Magellanic Cloud (LMC) was captured by the Multi Unit Spectroscopic Explorer instrument (MUSE) on ESO’s Very Large Telescope. The relatively small amount of dust in the LMC and MUSE’s acute vision allowed intricate details of the region to be picked out in visible light.

This region of the Large Magellanic Cloud (LMC) glows in striking colours in this image captured by the Multi Unit Spectroscopic Explorer (MUSE) instrument on ESO’s Very Large Telescope (VLT). The region, known as LHA 120-N 180B — N180 B for short — is a type of nebula known as an H II region (pronounced “H two”), and is a fertile source of new stars.

This zoom video starts with a wide view of the Milky Way and ends with a close-up look at a dazzling region of newly-forming stars in the HII region LHA 120-N 180B — also known as N180. This glowing region of newborn stars in the Large Magellanic Cloud (LMC) was captured by the Multi Unit Spectroscopic Explorer instrument on ESO’s Very Large Telescope. The relatively small amount of dust in the LMC and MUSE’s acute vision allowed intricate details of the region to be picked out in visible light. Credit: ESO/Digitized Sky Survey 2/N. Risinger (skysurvey.org). Music: Astral Electronic

The LMC is a satellite galaxy of the Milky Way, visible mainly from the Southern Hemisphere. At only around 160 000 light-years away from the Earth, it is practically on our doorstep. As well as being close to home, the LMC’s single spiral arm appears nearly face-on, allowing us to inspect regions such as N180 B with ease.

H II regions are interstellar clouds of ionised hydrogen — the bare nuclei of hydrogen atoms. These regions are stellar nurseries — and the newly formed massive stars are responsible for the ionisation of the surrounding gas, which makes for a spectacular sight. N180 B’s distinctive shape is made up of a gargantuan bubble of ionised hydrogen surrounded by four smaller bubbles.

Deep within the glowing cloud of the HII region LHA 120-N 180B, MUSE has spotted a jet emitted by a fledgling star — a massive young stellar object . This is the first time such a jet has been observed in visible light outside the Milky Way. Usually, such jets are obscured by their dusty surroundings, meaning they can only be detected at infrared or radio wavelengths by telescopes such as ALMA. However, the relatively dust-free environment of the LMC allowed this jet — named Herbig–Haro 1177, or HH 1177 for short — to be observed at visible wavelengths. At nearly 33 light-years in length, it is one of the longest such jets ever observed. This annotated image shows a close-up of the jet source and the bow shocks formed by the jet interacting with surrounding gas. [Hi-def images]

Deep within this glowing cloud, MUSE has spotted a jet emitted by a fledgling star — a massive young stellar object with a mass 12 times greater than our Sun. The jet — named Herbig–Haro 1177, or HH 1177 for short — is shown in detail in this accompanying image. This is the first time such a jet has been observed in visible light outside the Milky Way, as they are usually obscured by their dusty surroundings. However, the relatively dust-free environment of the LMC allows HH 1177 to be observed at visible wavelengths. At nearly 33 light-years in length, it is one of the longest such jets ever observed.

HH 1177 tells us about the early lives of stars. The beam is highly collimated; it barely spreads out as it travels. Jets like this are associated with the accretion discs of their star, and can shed light on how fledgling stars gather matter. Astronomers have found that both high- and low-mass stars launch collimated jets like HH 1177 via similar mechanisms — hinting that massive stars can form in the same way as their low-mass counterparts.

MUSE has recently been vastly improved by the addition of the Adaptive Optics Facility , the Wide Field Mode of which saw first light in 2017. Adaptive optics is the process by which ESO’s telescopes compensate for the blurring effects of the atmosphere — turning twinkling stars into sharp, high-resolution images. Since obtaining these data, the addition of the Narrow Field Mode, has given MUSE vision nearly as sharp as that of the NASA/ESA Hubble Space Telescope — giving it the potential to explore the Universe in greater detail than ever before.

More information

This research was presented in a paper entitled “An optical parsec-scale jet from a massive young star in the Large Magellanic Cloud” which appeared in the journal Nature.

The research team was composed of A. F. McLeod (who conducted this research while at the University of Canterbury, New Zealand and is now affiliated with the Department of Astronomy, University of California, Berkeley, and the Department of Physics and Astronomy, Texas Tech University, USA), M. Reiter (Department of Astronomy, University of Michigan, Ann Arbor, USA), R. Kuiper (Institute of Astronomy and Astrophysics, University of Tübingen, Germany), P. D. Klaassen (UK Astronomy Technology Centre, Royal Observatory Edinburgh, UK) and C. J, Evans (UK Astronomy Technology Centre, Royal Observatory Edinburgh, UK).

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It has 16 Member States: Austria, Belgium, the Czech Republic, Denmark, France, Finland, Germany, Ireland, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile and with Australia as a Strategic Partner. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope and its world-leading Very Large Telescope Interferometer as well as two survey telescopes, VISTA working in the infrared and the visible-light VLT Survey Telescope. ESO is also a major partner in two facilities on Chajnantor, APEX and ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre Extremely Large Telescope, the ELT, which will become “the world’s biggest eye on the sky”

Links

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Einstein’s Monsters: The Life and Times of Black Holes

Astronomy

Video: Night sky highlights for February 2019

February 4, 2019 TopSpacer

Highlights of the night sky in February from NASA JPL: What’s Up: February 2019 Skywatching from NASA | Solar System Exploration: NASA Science

What can you see in the February sky? Stars and planets with distinct red and blue colors, like Mars and Sirius. February also brings some pretty pairings with Venus, Saturn and the Moon, and the best opportunity of the year to catch a glimpse of Mercury. We also point out locations in the sky of several destinations recently visited by NASA spacecraft.