Category: Featured (page 1 of 12)

Many Complex Organic Compounds –Evolved Building Blocks of Life — Are Formed Where Stars Are Being Born

The Taurus Molecular Cloud is an active site for star formation.  It is also filled with complex organic molecules, including the kind that are building blocks for life.  The Cloud is 450 light years away, but similar star-forming regions with complex organics are found thoughout the galaxy. (Adapted, ESA/Herschel/NASA/JPL-Caltech)

Recent reports about the detection of carbon-based organic molecules on Mars by the instruments of the Perseverance rover included suggestions that some of the organics may well have fallen from space over the eons, and were then preserved on the Martian surface.

Given the cruciality of organics as building blocks of life –or even as biosignatures of past life — it seems surely important to understand more about how and where the organics might form in interstellar space, and how they might get to Mars, Earth and elsewhere.

After all, “follow the organics” has replaced the NASA rallying cry to “follow the water” in the search for extraterrestrial life in the solar system and cosmos.

And it turns out that seeking out and identifying organics in space is a growing field of its own that has produced many surprising discoveries.  That was made clear during a recent NASA webinar featuring Samantha Scibelli of the University of Arizona, a doctoral student in astronomy and astrophysics who has spent long hours looking for these organics in space and finding them.

She and associate professor of astronomy Yancy Shirley have been studying the presence and nature of complex organics in particular in a rich star-forming region, the Taurus Molecular Cloud.

Using the nearby radio observatory at Kitt Peak outside of Tucson, she has found a range of complex organics in starless or pre-stellar cores with the Cloud.  The campaign is unique in that some 700 hours of observing time were given to them, allowing for perhaps the most thorough observations of its kind.

The results have been surprising and intriguing.

In this mosaic image stretching 340 light-years across, the James Webb’s Near-Infrared Camera (NIRCam) displays the Tarantula Nebula star-forming region in a new light, including tens of thousands of never-before-seen young stars that were previously shrouded in cosmic dust. The most active region appears to sparkle with massive young stars, appearing pale blue. (NASA/STScI)

A first take-away (surprising to those unfamiliar with the field) is that complex organics are often detected in these star-forming regions throughout the galaxy and cosmos — just as they were found in many regions of the Taurus cloud.… Read more

The Cosmos, As Viewed By The James Webb Space Telescope

The iconic “Pillars of Creation” image, on left, was taken in visible light by the Hubble Space Telescope in 2014. A new, near-infrared-light view from NASA’s James Webb Space Telescope, at right, helps us peer through more of the dust in this star-forming region. The thick, dusty brown pillars are no longer as opaque and many more red stars that are still forming come into view.  The pillars of gas and dust seem darker and less penetrable in Hubble’s view, and they appear more permeable in Webb’s. (NASA)

The James Webb Space Telescope was developed to allow us to see the cosmos in a new way — with much greater precision, using infrared wavelengths to piece through dust around galaxies, stars and planets, and to look further back into time and space.

In the less than four months since the first Webb images were released,  the pioneering telescope has certainly shown us a remarkable range of abilities.  And as a result, we’ve been treated to some dazzling new views of the solar system, the galaxy and beyond.  This is just the beginning and we thankfully have years to come of new images and the scientific insights that come with them.

Just as the Hubble Space Telescope, with its 32 years of service and counting, ushered in a new era of space imagining and understanding, so too is the Webb telescope revolutionizing how we see and understand our world writ large.  Very large.

Neptune as seen by Voyager 2 during a flyby more than three decades ago, the Hubble Space Telescope last year, and the JWST this summer. ( NASA/ESA/CSA))

The differences between the Webb’s image and previous images of Neptune are certainly dramatic, in terms of color, precision and what they tell us about the planet.

Surely most striking in Webb’s new image is the crisp view of the planet’s rings, some of which have not been seen since NASA’s Voyager 2 became the first spacecraft to observe Neptune during its flyby in 1989. In addition to several bright, narrow rings, the Webb image clearly shows Neptune’s fainter, never-seen dust bands as well.

Neptune is an ice giant planet. Unlike Jupiter and Saturn, which consist primarily of hydrogen and helium, Neptune has an interior that is much richer in heavier elements (“heavier is the sense of not hydrogen or helium.) One of the most abundant heavy molecules is methane, which appears blue in Hubble’s visible wavelengths but largely white in the Webb’s near-infrared camera.… Read more

Clues About Conditions on Early Earth As Life Was Emerging

What set the stage for the emergence of life on early Earth?

There will never be a single answer to that question, but there are many partial answers related to the global forces at play during that period.  Two of those globe-shaping dynamics are the rise of the magnetic fields that protected Earth from hazardous radiation and winds from the Sun and other suns,  and plate tectonics that moved continents and in the process cycled and recycled the compounds needed for life.

A new paper published in the Proceedings of the National Academies of Science (PNAS)  reports from some of the world’s oldest rocks in Western Australia evidence that the Earth’s crust was pushing and pulling in a manner similar to modern plate tectonics at least 3.25 billion years ago.

Additionally, the study provides the earliest proof so far of the planet’s magnetic north and sound poles swapping places — as they have innumerable times since.  What the switching of the poles tells researchers is that there was an active, evolved magnetic field around the Earth from quite early days,.

Together, the authors say, the two findings offer clues into how geological  and electromagnetic changes may have produced an environment more conducive to the emergence of life on Earth.

 

The early Earth was a hellish place with meteor impact galore and a choking atmosphere.  Yet fairly early in its existence, the Earth developed some of the key geodynamics needed to allow life to emerge.  The earliest evidence that microbial life was presented is dated at 3.7 billion years ago, not that long after the formation of the planet 4.5 billion years ago. (Simone Marchi/SwRI)

According to author Alec Brenner, a doctoral student at Harvard’s Paleomagnetics Lab,  the new research “paints this picture of an early Earth that was already really geodynamically mature. It had a lot of the same sorts of dynamic processes that result in an Earth that has essentially more stable environmental and surface conditions, making it more feasible for life to evolve and develop.”

And speaking specifically of the novel readings of continental movement 3.25 billion years ago, fellow author and Harvard professor Roger Fu said that “finally being able to reliably read these very ancient rocks opens up so many possibilities for observing a time period that often is known more through theory than solid data.”… Read more

The Virtual Planetary Lab and Its Search for What Makes an Exoplanet Habitable, or Even Inhabited

As presented by the Virtual Planetary Laboratory, exoplanet habitability is a function of the interplay of processes between the planet, the planetary system, and host star.  These interactions govern the planet’s evolutionary trajectory, and have a larger and more diverse impact on a planet’s habitability than its position in a habitable zone. (Meadows and Barnes)

For more than two decades now, the Virtual Planetary Laboratory (VPL) at the University of Washington in Seattle has been at the forefront of the crucial and ever-challenging effort to model how scientists can determine whether a particular exoplanet is capable of supporting life or perhaps even had life on it already.

To do this, VPL scientists have developed or combined models from many disciplines that characterize and predict a wide range of planetary, solar system and stellar attributes that could identify habitability, or could pretty conclusively say that a planet is not habitable.

These include the well known questions of whether water might be present and if so whether temperatures would allow it to be sometimes in a liquid state, but on to questions involving whether an atmosphere is present, what elements and compounds might be in the atmospheres, the possible orbital evolution of the planet, the composition of the host star and how it interacts with a particular orbiting planet and much, much more, as shown in the graphic above.

This is work that has played a significant role in advancing astrobiology — the search for life beyond Earth.

More specifically, the VPL approach played a considerable part in building a body of science that ultimately led the Astro2020 Decadal Study of the National Academy of Sciences to recommend last year that the NASA develop its  first Flagship astrobiology project — a mission that will feature a huge space telescope able to study exoplanets for signs of biology in entirely new detail.  That mission, approved but not really defined yet, is not expected to launch until the 2040s.

With that plan actually beginning to move forward, the 132 VPL affiliated researchers at 28 institutions find themselves at another more current-day inflection point:  The long-awaited James Webb Space Telescope has begun to collect and send back what will be a massive and unprecedented set of spectra  of chemicals from the atmospheres of distant planets.

The Virtual Planetary Laboratory has modeled the workings of exoplanets since 2001, looking for ways to predict planetary conditions based on a broad range of measurable factors.

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The James Webb Space Telescope Begins Looking at Exoplanets

 

Artist rendering of Gliese (GJ) 436 b  is a Neptune-sized planet that orbits a red dwarf  star.  Red dwarfs are cooler, smaller, and less luminous than the Sun. The planet completes one full orbit around its parent star in just a little over 2 days. It is made, scientists say, of extremely hot ice.  (NASA/JPL-Caltech/UCF)

The James Webb Space Telescope has begun the part of its mission to study the atmospheres of 70 exoplanets in ways, and at a depth, well beyond anything done so far.

The telescope is not likely to answer questions like whether there is life on distant planet — its infrared wavelengths will tell us about the presence of many chemicals in exoplanet atmospheres but little about the presence of the element most important to life on Earth, oxygen.

But it is nonetheless undertaking a broad study of many well-known exoplanets and is likely to produce many tantalizing results and suggest answers to central questions about exoplanets and their solar systems.

Many Worlds has earlier looked at the JWST “early release” program, under which groups are allocated user time on the telescope under the condition that they make their data public quickly.  That way other teams can understand better how JWST works and what might be possible.

Another program gives time to scientists who worked on the JWST mission and on its many instruments.  They are given guaranteed time as part of their work making JWST as innovative and capable as it is.

One of the scientist in this “guaranteed time observations program” is Thomas Greene, an astrophysicist at NASA Ames Research Center.  The groups he leads have been given 215 hours of observing time for this first year (or more) of Cycle 1 of JWST due to his many contributions to the JWST mission as well as his history of accomplishments.

In a conversation with Greene, I got a good sense of what he hopes to find and his delight at the opportunity.  After all, he said, he has worked on the JWST idea and then mission since 1997.

“We will be observing a diverse sample of exoplanets to understand more about them and their characteristics,” Greene said.  “Our goal is to get a better understanding of how exoplanets are similar to and different from those in our solar system.”

And the JWST spectra will tell them about the chemistry, the composition and the thermal conditions on those exoplanets, leading to insights into how they formed, diversified and evolved into planets often so unlike our own.Read more

Icy Moons, And Exploring The Secrets They Hold

Voyager 2’s flew by the Uranian moon Miranda in 1986 and the spacecraft spent 17 minutes taking  photos to make this high-resolution portrait.  Miranda has three oval and trapezoid coronae, tectonic features whose origins remain debated. (NASA / JPL / Ted Stryk)

When it come to habitable environments in our solar system, there’s Earth, perhaps Mars billions of years ago and then a slew of ice-covered moons that are likely to have global oceans under their crusts.  Many of you are familiar with Europa (a moon of Jupiter) and Enceladus (a moon of Saturn) — which have either been explored by NASA or will be in the years ahead.

But there quite a few others icy moons that scientists find intriguing and just possibly habitable.  There is Ganymede,  the largest moon of Jupiter and larger than Mercury but only 40 percent as dense, strongly suggesting a vast supply of water inside rather than rock.

There’s Saturn’s moon Titan, which is known for its methane lakes and seas on the surface but which has a subterranean ocean as well.  There is Callisto, the second largest moon of Jupiter and an subsurface-ocean candidates and even Pluto and Ceres, now called dwarf planets that show signs of having interior oceans.

And of increasing interest are several of the icy moons of Uranus, particularly Ariel and Miranda.  Each has features consistent with a subsurface ocean and even geological activity.  Although Uranus is a distant planet, well past Jupiter and Saturn and would take more than a decade to just get there, the possibility of a future Uranus mission is becoming increasingly real.

The National Academy of Sciences (NAS) Decadal Survey for planetary science rated a Uranus mission as the highest priority in the field, and just today (Aug. 18) NASA embraced the concept.

At a NASA Planetary Science Division town hall meeting, Director Lori Glaze said the agency was “very excited” about the Uranus mission recommendation from the National Academy and that she hoped and expected some studies could be funded and begun in fiscal 2024.

If a Uranus mission is fully embraced,  it would be the first ever specifically to an ice giant system — exploring the planet and its moons.  This heightened interest reflects the fact that many in the exoplanet field now hold that ice giant systems are the most common in the galaxy and that icy moons may well be common as well.… Read more

Evolving Views of Our Heliosphere Home

Does this model show of the actual shape of the heliosphere, with lines of magnetic fields around it? New research suggests so. The size and shape of the magnetic “force field” that protects our solar system from deadly cosmic rays has long been debated by astrophysicists. (Merav Opher, et. al)

We can’t see the heliosphere.  We know where it starts but not really where it ends.  And we are pretty certain that most stars, and therefore most planetary systems, are bounded by heliospheres, or “astropheres,” as well.

It has a measurable physical presence, but it is always changing.  And although it is hardly well known, it plays a substantial role in the dynamics of our solar system and our lives.

As it is studied further and deeper, it has become apparent that the heliosphere might be important — maybe even essential – for the existence of life on Earth and anywhere else it may exist.  Often likened to an enormous bubble or cocoon, it is the protected space in which our solar system and more exists.

Despite the fact that it is the largest physical system in the entire solar system, the heliosphere was only discovered at the dawn of the space age in the late 1950’s, when it was theorized by University of Chicago physicist Eugene Parker as being the result of what he termed the solar wind.

It took another decade for satellite measurements to confirm its existence and to determine some of its properties — that it is made up of an endless supply of charged particles that are shot off the sun — too hot to form into atoms. Together these particles,  which are superimposed with the interplanetary magnetic field, constitute the ingredients of he heliosphere.

Just as the Earth’s magnetic fields protect us from some of the effects of the Sun’s hazardous emanations, the heliosphere protects everything inside its bubble from many, though not all, of the incoming and more hazardous high-energy cosmic rays headed our way.

As measurable proof that the heliosphere does offer significant protection, when the Voyager 1 spacecraft left the heliosphere in 2012 and entered the intersellar medium, instruments onboard detected a tripling of amount of cosmic radiation suddenly hitting the spacecraft.

A comet-shaped traditional view of the structure of the heliosphere, with the sun in the middle of the circle, planets orbiting around and the solar wind trailing as the Sun orbits the Milky Way.  

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“Nature Has Become More Beautiful.” Physicist Eugene Parker and his Life Unlocking Secrets Of The Sun

 

Parker with an image of the solar corona, the outermost portion of Sun’s atmosphere.  Parker brought new understanding to the nature and workings of the corona and the solar wind, which originates in the corona. (University of Chicago)

When  Eugene Parker was 16 years old,  he decided he didn’t want to spend the summer hanging out in suburban Detroit.  So Parker went up to the state capital looking to buy some tax delinquent land held by the state.

He selected a 40-acre piece of woods in far-off Cheboygan County, not far from Mackinac Island.  There was nothing on the land but trees.  He bought it with $120 from his own earlier summertime earnings.

Over the next three summers, Parker, his younger brother and sometimes a cousin and a friend constructed a log cabin on the land.  Because this was during World War II and gas was strictly rationed,  they couldn’t ask their parents for a ride up, and so they often bicycled the more than 300 miles to their homestead.

The cabin still doesn’t have electricity or indoor running water, but it has been used regularly by Parker and his family for almost 80 years.  And in many ways, that cabin reflects the basic character, the drive and the profound originality of the boy who built it and went on to become one of the great theoretical physicists of the 20th century.

The young Parker atop a birch  tree in 1943, on the site where his northern Michigan cabin would be built. (Courtesy of the Parker family.)

Eugene Parker, who passed away earlier this month at 94, has been hailed as the father of solar physics and is perhaps best known as the man who — basically single-handedly and despite many eminent critics –came up with the theory of the “solar wind,” a torrent of charged particles and magnetic fields that always and in all directions is blasting out from the Sun.

Parker’s innumerable achievements in his field, as well as his old-school civility and demeanor, earned him the first and only honor of its kind given by NASA — having a major space mission named after him while alive.

Ailing and aged 91, he nonetheless went with his family down to Florida in 2018 to watch the launch of the Parker Solar Probe — an extraordinary mission that flies through the blast furnace of the Sun’s corona in its effort to learn more about the origins of the solar wind and the forces at play that produce that still mysterious solar corona.… Read more

The World’s Most Capable Space Telescope Readies To Observe. What Will Exoplanet Scientists Be Looking For?

This artist’s concept shows what the TRAPPIST-1 planetary system may look like, based on available data about the planets’ diameters, masses and distances from the host star.  The James Webb is expected to begin science observations this summer. (NASA/JPL-Caltech)

The decades-long process of developing, refining, testing, launching, unfurling and now aligning and calibrating the most capable space telescope in history is nearing fruition.  While NASA has already released a number of “first light” images of photons of light moving through the James Webb Space Telescope’s optical system, the  jaw-dropping “first light” that has all the mirrors up and running together to produce an actual scientific observation is a few months off.

Just as the building and evolution of the Webb has been going on for years, so has the planning and preparation for specific team observation “campaigns.”   Many of these pertain to the earliest days of the universe, of star and galaxy formation and other realms of cosmology,  but an unprecedented subset of exoplanet observations is also on its way.

Many Worlds earlier discussed the JWST Early Release Science Program, which involves observations of gigantic hot Jupiter planets to both learn about their atmospheres and as a way to collect data that will guide exoplanet scientists in using JWST instruments in the years ahead.

Now we’ll look at a number of specific JWST General Observation and Guarantreed Time efforts that are more specific and will collect brand new information about some of the major characteristics and mysteries of a representative subset of the at least 100 billion exoplanets in our galaxy.

This will be done by using three techniques including transmission spectroscopy — collecting and analyzing the light that passes through an exoplanet’s atmosphere as it passes in front of its Sun.  The JWST will bring unprecedented power to characterizing the wild diversity of exoplanets now known to exist; to the question of whether “cool” and dim red dwarf stars (by far the most common in the galaxy) can maintain atmospheres; to newly sensitive studies of the chemical makeup of exoplanet atmospheres; and to the many possibilities of the TRAPPIST-1 exoplanets, a seven rocky planet solar system that is relatively nearby.

An artist’s interpretation of GJ 1214b,one of a group of super-Earth to mini-Neptune sized planets to be studied in the JWST Cycle1 observations. The planet is known to be covered by a thick haze which scientists expect the JWST to pierce as never before and allow them to study atmospheric chemicals below.

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The James Webb Space Telescope And Its Exoplanet Mission (Part 1)

 

This artist’s conception of the James Webb Space Telescope in space shows all its major elements fully deployed. The telescope was folded to fit into its launch vehicle, and then was slowly unfolded over the course of two weeks after launch. (NASA GSFC/CIL/Adriana Manrique Gutierrez)

 

The last time Many Worlds wrote about the James Webb Space Telescope, it was in the process of going through a high-stakes, super-complicated unfurling.  About 50 autonomous deployments needed to occur after launch to set up the huge system,  with 344 potential single point failures to overcome–individual steps that had to work for the mission to be a success.

That process finished a while back and now the pioneering observatory is going through a series of alignment and calibration tests, working with the images coming in from the 18 telescope segments to produce one singular image.

According to the Space Telescope Science Institute,  working images from JWST will start to appear in late June, though there may be some integrated  “first light” images slightly earlier.

Exciting times for sure as the observatory begins its study of the earliest times in the universe, how the first stars and galaxies formed, and providing a whole new level of precision exploration of exoplanets.

Adding to the very good news that the JWST successfully performed all the 344 necessary steps to unfurl and that the mirror calibration is now going well is this:  The launch itself went off almost exactly according to plan.  This means that the observatory now has much more fuel on hand than it would have had if the launch was problematic. That extra fuel means a longer life for the observatory.

 

NASA announced late last month that it completed another major step in its alignment process of the new James Webb Space Telescope, bringing its test images more into focus. The space agency said it completed the second and third of a seven-phase process, and had accomplished “Image Stacking.” Having brought the telescope’s mirror and its 18 segmented parts into proper alignment, it will now begin making smaller adjustments to the mirrors to further improve focus in the images. (NASA/STScI)

Before launch, the telescope was expected to last for five years.  Now NASA has said fuel is available for a ten year mission and perhaps longer.  Quite a start.

(A NASA update on alignment and calibration will be given on Wednesday. … Read more

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