NASA to Unveil the Secrets of Nearby Dwarf Galaxies and Properties of Dark Matter – SciTechDaily

The dwarf galaxy Sculptor, above, is a companion to the Milky Way galaxy. Astronomers will use Webb to study the motions of stars in Sculptor and Draco, another dwarf companion to the Milky Way. By studying how the stars move, the researchers will be able to determine how the dark matter is distributed in these galaxies. Credit: ESA/Hubble, Digitized Sky Survey 2

In two separate studies using NASA’s upcoming James Webb Space Telescope, a team of astronomers will observe dwarf galaxy companions to the Milky Way and the nearby Andromeda galaxy. Studying these small companions will help scientists learn about galaxy formation and the properties of dark matter, a mysterious substance thought to account for approximately 85% of the matter in the universe.

In the first study, the team will gain knowledge of dark matter by measuring the motions of stars in two dwarf companions to the Milky Way.  In the second study, they will examine the motions of four dwarf galaxies around our nearest large galactic neighbor, the Andromeda galaxy. This will help determine if some of Andromeda’s satellite galaxies orbit inside a flat plane, like the planets around our Sun. If they do, that would have important implications for understanding galaxy formation. The principal investigator for both programs is Roeland van der Marel of the Space Telescope Science Institute (STScI) in Baltimore, Maryland.

Observing Stellar Motions in Dwarf Galaxy Companions to the Milky Way

The nearest galaxies to our own Milky Way are its companion dwarf galaxies, which are much smaller than the Milky Way. Van der Marel and his team plan to study the motions of stars in two of these dwarf galaxies, Draco and Sculptor. The orbits of the stars are governed by the gravity arising from the dark matter in each galaxy. By studying how the stars move, the researchers will be able to determine how the dark matter is distributed in these galaxies.

“How structures in the universe formed depends on the properties of the dark matter that comprises most of the mass in the universe,” explained van der Marel. “So we know there’s dark matter, but we don’t know what actually makes up this dark matter. We just know that there is something in the universe that has gravity and it pulls on things, but we don’t really know what it is.” 

Artist’s rendering of the James Webb Space Telescope. Credit: Northrop Grumman

The team will study the distribution of dark matter in the centers of the dwarf galaxies to determine the temperature properties of this mysterious phenomenon. If dark matter is “cold,” its density will be very high near the centers of the galaxies. If dark matter is “warm,” it will be more homogenous throughout the area approaching the galactic centers.

At the same time Webb’s Near Infrared Camera (NIRCam) is studying the centers of Draco and Sculptor, another instrument, the Near Infrared Imager and Slitless Spectrograph (NIRISS), will be probing the outskirts of the dwarf galaxies. “These simultaneous observations will provide some insight into how stars move differently near the center and the outskirts of the dwarf galaxies,” said co-investigator Tony Sohn of STScI. “They will also allow two independent measures of the same galaxy, to check for any systematic or instrumental effects.”

Because Webb has approximately six times the light collection area of NASA’s Hubble Space Telescope, the team can measure the motions of stars much fainter than what Hubble can see.  The more stars included in a study, the more accurately the team can model the dark matter that influences their motions.

Studying the Motion of Dwarf Galaxy Companions to Andromeda

The nearest large neighbor galaxy of our Milky Way, Andromeda has numerous dwarf galaxy companions, just as the Milky Way does. Van der Marel and his team plan to study how four of those dwarf galaxies are moving around Andromeda, to determine if they are grouped within a flat plane in space, or whether they are moving around Andromeda in all directions.

Unlike the first observation program, the team is not trying to measure how stars inside the dwarf galaxies move. In this study, they are trying to determine how the dwarf galaxies as a whole move around Andromeda. This will provide insights into the process whereby large galaxies form by accretion and accumulation of smaller galaxies, and how exactly that works. 

In most models, dwarf galaxies that surround larger galaxies are not expected to lie in a plane. Typically, scientists would expect dwarf galaxies to fly around bigger galaxies in random ways. Slowly, these dwarf companions would lose energy and be accreted into the larger galaxy, which would grow larger still.

However, for both for the Milky Way and Andromeda, several studies have suggested that at least some fraction of the dwarf galaxies lie in a plane, and may even be rotating in that plane. One of the ways to determine if that’s true is to measure their three-dimensional motions. If the motions are actually in the plane, that would suggest that the dwarf galaxies will stay in a plane. But if the companion dwarfs appear to be in a plane but their motions are in all directions, that would indicate a chance alignment and not a long-lasting structure. 

If the dwarf galaxies do line up in a plane, that can mean one of several things. It could be that a good fraction of the dwarf companions fell into orbit around Andromeda as a single group. If that were the case, the dwarfs would retain “memory” that they all fell in together, and they would exhibit similar dynamical properties right now.

Another possibility is that the dwarf galaxies of Andromeda formed as what are called “tidal dwarf galaxies.” These gravitationally bound collections of gas and stars form during mergers or interactions between large spiral galaxies. They are as massive as dwarf galaxies but are not dominated by dark matter, as scientists believe most of the dwarf galaxies around us are. It’s possible that a merger of two large galaxies with a lot of gas could form some dwarf galaxies that end up in a single planar structure, but that would be unusual, because scientists don’t think that tidal dwarf galaxies are the predominant type of dwarf galaxy in the universe. Dwarf galaxies are typically known to form inside of dark matter clouds called halos. 

Either case could mean that galaxy formation may be more complicated than researchers sometimes think. Either would provide additional constraints on scientists who develop theoretical models of galaxy formation. 

Webb’s Extreme Accuracy and Precision

In both programs, the team will push Webb to its limits in terms of accuracy and precision. “It’s a very tricky situation, because basically what we want to measure are very tiny motions,” explained co-investigator Andrea Bellini of STScI. “The accuracy we want to achieve is like measuring something that moves a few inches a year on the surface of the Moon, as seen from Earth.”

Both studies are Guaranteed Time Observations (GTO) programs allocated to the team of the Webb Telescope Scientist, Matt Mountain. He is also president of the Association of Universities for Research in Astronomy (AURA), headquartered in Washington, D.C.

The James Webb Space Telescope will be the world’s premier space science observatory when it launches in 2021. Webb will solve mysteries in our solar system, look beyond to distant worlds around other stars, and probe the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency.

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NASA unveils concept lander capable of carrying a 660lbs rover to one of the lunar poles – Daily Mail

NASA’s moon lander revealed: US space agency unveils plans for a robotic spacecraft to deliver a 660lbs rover to one of the lunar poles ahead of its 2024 manned mission

• The US space agency’s goal is to establish a presence on the moon by 2028
• This will call for many manned and unmanned missions to the lunar surface 
• The ‘pallet lander’ concept was drawn up with economy and simplicity in mind
• NASA hopes that the example will inspire designs by other manufacturers

By Ian Randall For Mailonline

Published: 06:38 EST, 26 November 2019 | Updated: 10:38 EST, 26 November 2019

NASA has revealed a concept of what a future moon lander might look like, as it strives to establish a presence on the lunar surface by the year 2024.

Dubbing the concept spacecraft a ‘pallet lander’, the US space agency has suggested that the design could be used to explore the polar regions of the moon.

Such a craft would be capable of carrying a 300 kilogram (661 lbs) rover and payload to the moon’s surface.

According to NASA, the concept — intended to inspire other lander designs from outside the space agency — was drawn up with simplicity and economy in mind.

However, its designers admit that such a lander would not be expected to survive the lunar night.

The pallet lander would travel aboard a commercial launch vehicle in order to reach the moon.

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NASA has revealed a concept of what a future moon lander (pictured) might look like, as it strives to return to the lunar surface by the year 2024 and establish a presence

‘This lander was designed with simplicity in mind to deliver a 300 kilogram (661 lbs) rover to a lunar pole,’ said Logan Kennedy, the project’s lead systems engineer at NASA’s Marshall Space Flight Center in Huntsville, Alabama. 

‘We used single string systems, minimal mechanisms and existing technology to reduce complexity, though advancements in precision landing were planned to avoid hazards and to benefit rover operations.’

‘We keep the rover alive through transit and landing so it can go do its job.’

‘As robotic lunar landers grow to accommodate larger payloads, simple but high-performing landers with a contiguous payload volume will be needed,’ he added.

‘This concept was developed by a diverse team of people over many years and meets that need.’

‘We hope that other lander designers can benefit from our work.’

The design comes as the US space agency races to return to the moon, trying to meet the 2024 deadline set by president Donald Trump’s administration

According to NASA, the concept — intended to inspire other lander designs from outside the space agency — was drawn up with simplicity and economy in mind. The pallet lander would travel aboard a commercial launch vehicle in order to reach the moon

The design comes as the US space agency races to return to the moon, trying to meet the 2024 deadline set by president Donald Trump’s administration.

NASA reportedly wants to establish a ‘sustainable human presence on the moon by 2028’ — for which many manned and unmanned missions will be required.

They hope to make new scientific discoveries and demonstrate new technological advancements alongside building a lunar economy with the help of private companies. 

The full technical paper describing the lander design has been published on the NASA website. 

WHEN IS NASA GOING BACK TO THE MOON?

In a statement in March, NASA Administrator Jim Bridenstine doubled down on plans to send humans first to the moon and then to Mars and said NASA is on track to have humans back on the moon by 2028.

The plan relies on the developing Space Launch System and Orion spacecraft, along with the Gateway orbital platform.

SLS and Orion are expected to be ready for their first uncrewed test flight in 2020.

Construction on Gateway – an orbiting lunar outpost – is expected to begin as soon as 2022.

‘We will go to the Moon in the next decade with innovative, new technologies and systems to explore more locations across the lunar surface than ever before,’ Bridenstine said.

‘This time, when we go to the Moon, we will stay.

‘We will use what we learn as we move forward to the Moon to take the next giant leap – sending astronauts to Mars.’

Vice President Mike Pence, however, tore up these plans and statements when he unexpectedly revealed a new deadline in March stating intentions to put humans on the moon by 2024 – four years earlier. 

The VP called on NASA to ‘reignite the spark of urgency’ for space exploration and make it a priority to set ‘bold goals’ and stay on schedule.

NASA administrator Jim Bridenstine added a week later, at the start of April, that the agency would get ‘really close’ to delivering a plan by April 15. 

This has been missed by several weeks and the House Science Committee is now vocalising its displeasure at having no viable plan or programme from the space agency.  

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NASA finds sugars on meteorites for first time in a step for theory that life evolved from Asteroids – Daily Mail

NASA finds evidence on three meteorites that life on Earth evolved from Asteroids

• NASA says three meteorites were found to contain several types of sugar
• Among them was ribose which is the key ingredient of RNA 
• Past analyses have also turned up amino acids, another building block of life
• Scientists say the sugars likely came from space and not Earth 

By James Pero For Dailymail.com

Published: 12:11 EST, 21 November 2019 | Updated: 15:38 EST, 21 November 2019

NASA scientists say they’ve made a sweet discovery while analyzing three meteorites that crashed to Earth.

On Tuesday, NASA announced that they’ve found the first evidence of sugars on meteorite specimens which adds to a growing body of evidence that their parent objects, Asteroids, may carry the building blocks for life.

‘The sugar in DNA (2-deoxyribose) was not detected in any of the meteorites analyzed in this study,’ said Danny Glavin, a co-author of the study at NASA Goddard in a statement. 

‘This is important since there could have been a delivery bias of extraterrestrial ribose to the early Earth which is consistent with the hypothesis that RNA evolved first.’ 

Meteoroids studied by researchers from NASA were found to contain several types of sugar including ribose, which is a building block for organic life (Stock image)

Among the sugars identified are ribose, arabinose, xylose, and lyxose – not sucrose which sweetens refined sugar on Earth. Those sugars, say researchers, were formed as the result of chemical reactions that occurred in space.

The existence of ribose in particular is a significant finding since its the primary ingredient in RNA, a fundamental agent in all biological life – especially early on in Earth’s history. 

Another building blocks of early life, amino acids, have also been identified on meteorites in the past.

Researchers say they’ve ruled out the possibility that those sugars were actually picked up upon the meteorites’ contact with Earth by analyzing the isotopes. 

WHAT IS A METEOROID? 

A meteoroid is a small chunk of asteroid or comet.

When it enters Earth’s atmosphere it becomes a meteor, fireball or shooting star.

The pieces of rock that hit the ground are meteorites, and are valuable to collectors.

The remnants must be analyzed by a lab to be accredited as meteorites.

Samples contained carbon-13 instead of the more common carbon-12 and was heavily enriched beyond the amount that scientists usually see in biology here on Earth. 

Researchers plan to further study meteorites to get a better idea how common the sugars may be and also the sugars’ characteristics. 

Since ancient meteorite impacts from long ago may have delivered the biological material that lead to life forms, scientists stand to learn something about how those organisms evolved into what we see today.

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NASA Photos Show Insect- and Reptile-Like Life Forms on Mars, Entomologist Says | Astrobiology – Sci-News.com

Ohio University Emeritus Professor William Romoser has analyzed photos from NASA’s various Mars rovers, mostly from the rover Curiosity, and found insect/arthropod- and reptile-like organisms (both as fossils and living creatures) in the images.

Various anatomical structures seen in different photos: (A – E) and probably (F) are ‘beelike,’ but not necessarily the same type; (A & B) a specimen whose head appears to have turned in the direction of the camera (based on the scale provided in the photo from which this was extracted, this individual is estimated to be approximately 20 inches long); (C) abdomen of specimen from (A); (D) individual on ground with head facing left with head & thorax visible; (E) individual flying with legs evident and, though in flight, somewhat comparable to the specimen in (D); compound eyes and hindlegs labeled in two positions since in motion; relative to (D & E), the locations, shapes, sizes, and appearance of the legs suggest that the forelgs, with putative distal chelate structures, are grasping; the midlegs, digging; and the hindlegs, jumping & running; (F) specimen on ground with wing(s) toward the right; longitudinal veins, cross veins, and wing cells evident; (G) part of wing of specimen apparently caught on the rover; inset: enlarged portion of wing; longitudinal veins, cross veins, and cells are evident. Image credit: William Romoser, doi: 10.13140/RG.2.2.12363.95520.

“There has been and still is life on Mars,” said Professor Romoser, who was an entomology professor at Ohio University for 45 years and co-founded its Tropical Disease Institute, also spent nearly 20 years as a visiting vector-borne disease researcher at the U.S. Army Medical Research Institute of Infectious Diseases.

“There is apparent diversity among the Martian insect-like fauna which display many features similar to terran insects that are interpreted as advanced groups — for example, the presence of wings, wing flexion, agile gliding/flight, and variously structured leg elements.”

“While the Martian rovers, particularly Curiosity, have been looking for indicators of organic activity, there are a number of photos which clearly depict the insect- and reptile-like forms.”

“Numerous photos show images where arthropod body segments, along with legs, antennae and wings, can be picked out from the surrounding area, and one even appears to show one of the insects in a steep dive before pulling up just before hitting the ground,” he said.

Insect-like forms in flight: (A) at least two apparent insect-like creatures flying close to one another; (B) putative insect-like forms in a darkening sky; (C & D) extracts from (B) with evidence of wings beating (light spots encircling the dark bodies); (E) an insect-like specimen (‘bee’) that appears to have flown right to left from what could be a cave or an entrance to the underground; (F) two putative insect-like specimens in flight contrasted with the darkening sky; insert: enlarged view. Image credit: William Romoser, doi: 10.13140/RG.2.2.12363.95520.

Professor Romoser said he used several criteria in the study: dramatic departure from the surroundings, clarity of form, body symmetry, segmentation of body parts, repeating form, skeletal remains, and observation of forms in close proximity to one another.

“An exoskeleton and jointed appendages are sufficient to establish identification as an arthropod,” he explained.

“Three body regions, a single pair of antennae, and six legs are traditionally sufficient to establish identification as insect on Earth. These characteristics should likewise be valid to identify an organism on Mars as insect-like.”

“On these bases arthropodan insect-like forms can be seen in the Mars rover photos.”

“Many insect-like creatures and putative diversity were observed. The most common insect-like forms are robust and loosely resemble bumble bees or carpenter bees on Earth. For convenience, I’ll refer to these creatures as ‘bees’ from this point on.”

“The ‘bees’ appear to vary in size and type. Several characteristic insect/arthropod anatomical features were identifiable, not all on the same individual, but as a mosaic among individuals.”

“Distinct flight behavior was evident in many images. In one case observed, the flight maneuver was impressive with the individual ‘bee’ plunging straight down the side of a cliff and leveling off just before hitting the ground.”

“The insect-like fauna observed appeared to be sheltering/nesting in caves, in burrows beneath the surface, and in specialized structures.”

Insect- and reptile-like forms: (A) frontal view of a putative reptile-like fossil compared to a terran snake: (1) frontal view of putative fossil (circled) in a debris field; (2) enlarged frontal view of fossil; (3) midline symmetry indicated; (4) eyes and small oral opening circled; (5) bilateral punctate structures indicated; (6) large, full-gape, oral opening; (7) eyes, lateral punctate structures, and large mouth capable of gaping are indicated; (8) frontal view of Eastern King Snake head; (9) King snake with eyes and bilateral punctuate structures circled; (B) putative fossil insect on its dorsum with head to the top, and with selected structures labeled; (C & D) apparent predatory behavior showing reptile-like creature with insect-like creature in its mouth. Image credit: William Romoser, doi: 10.13140/RG.2.2.12363.95520.

“Possible predation of the insect-like types by reptile-like creatures and putative insect-like (‘bee’) and reptile-like fossils were seen,” he said.

According to the researcher, interpretations of insect- and reptile-like creatures he described may change in the future as knowledge of life on Mars evolves, but that the sheer volume of evidence is compelling.

“Given evidence for the presence of insect/arthropod and reptile-like organisms beyond the confines of Earth, perhaps ‘astroentomology’ and ‘astroherpetology’ will emerge as important topics within the field of astrobiology,” Professor Romoser concluded.

He presented the findings November 19, 2019 at the National Meeting of the Entomological Society of America in St. Louis, Missouri.

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William Romoser. Does Insect/Arthropod Biodiversity Extend Beyond Earth? Entomological Society of America 2019; doi: 10.13140/RG.2.2.12363.95520