суббота, 9 марта 2019 г.

Mars in a Box: How a Metal Chamber on Earth Helps us do Experiments on MarsInside this...

Mars in a Box: How a Metal Chamber on Earth Helps us do Experiments on Mars

Inside this metal box, it’s punishingly cold. The air is unbreathable. The pressure is so low, you’d inflate like a balloon. This metal chamber is essentially Mars in a box — or a near-perfect replica of the Martian environment. This box allows scientists to practice chemistry experiments on Earth before programming NASA’s Curiosity rover to carry them out on Mars. In some cases, scientists use this chamber to duplicate experiments from Mars to better understand the results. This is what’s happening today.

The ladder is set so an engineer can climb to the top of the chamber to drop in a pinch of lab-made Martian rock. A team of scientists is trying to duplicate one of Curiosity’s first experiments to settle some open questions about the origin of certain organic compounds the rover found in Gale Crater on Mars. Today’s sample will be dropped for chemical analysis into a tiny lab inside the chamber known as SAM, which stands for Sample Analysis at Mars. Another SAM lab is on Mars, inside the belly of Curiosity. The SAM lab analyzes rock and soil samples in search of organic matter, which on Earth is usually associated with life. Mars-in-a-box is kept at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

This is Goddard engineer Ariel Siguelnitzky. He is showing how far he has to drop the sample, from the top of the test chamber to the sample collection cup, a small capsule about half an inch (1 centimeter) tall (pictured right below). On Mars, there are no engineers like Siguelnitzky, so Curiosity’s arm drops soil and rock powder through small funnels on its deck. In the photo, Siguelnitzky’s right hand is pointing to a model of the tiny lab, which is about the size of a microwave. SAM will heat the soil to 1,800 degrees Fahrenheit (1,000 degrees Celsius) to extract the gases inside and reveal the chemical elements the soil is made of. It takes about 30 minutes for the oven to reach that super high temperature.

Each new sample is dropped into one of the white cups set into a carousel inside SAM. There are 74 tiny cups. Inside Curiosity’s SAM lab, the cups are made of quartz glass or metal. After a cup is filled, it’s lifted into an oven inside SAM for heating and analysis.

Amy McAdam, a NASA Goddard geochemist, hands Siguelnitzky the sample. Members of the SAM team made it in the lab using Earthly ingredients that duplicate Martian rock powder. The powder is wrapped in a nickel capsule (see photo below) to protect the sample cups so they can be reused many times. On Mars, there’s no nickel capsule around the sample, which means the sample cups there can’t be reused very much.

SAM needs as little as 45 milligrams of soil or rock powder to reveal the secrets locked in minerals and organic matter on the surface of Mars and in its atmosphere. That’s smaller than a baby aspirin!

Siguelnitzky has pressurized the chamber – raised the air pressure to match that of Earth – in order to open the hatch on top of the Mars box.

Now, he will carefully insert the sample into SAM through one of the two small openings below the hatch. They’re about 1.5 inches (3.8 centimeters) across, the same as on Curiosity. Siguelnitzky will use a special tool to carefully insert the sample capsule about two feet down to the sample cup in the carousel.

Sample drop.

NASA Goddard scientist Samuel Teinturier is reviewing the chemical data, shown in the graphs, coming in from SAM inside Mars-in-a-box. He’s looking to see if the lab-made rock powder shows similar chemical signals to those seen during an earlier experiment on Mars.

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com

Ferberite Pyrite & Quartz | #Geology #GeologyPage…

Ferberite Pyrite & Quartz | #Geology #GeologyPage #Mineral

Locality: Kara Oba, Karaganda Oblast, Kazakhstan

Size: 12.5 × 8 × 7 cm

Photo Copyright © MONTAN PARK /e-rocks. com

Geology Page



Wulfenite | #Geology #GeologyPage #Mineral Locality: Ahmad…

Wulfenite | #Geology #GeologyPage #Mineral

Locality: Ahmad Abad, Yazd Province, Iran

Size: 8.7 x 7.6 x 6.4 cm

Photo Copyright © Saphira Minerals

Geology Page



2019 March 9 Crescent Enceladus Image Credit: Cassini Imaging…

2019 March 9

Crescent Enceladus
Image Credit: Cassini Imaging Team, SSI, JPL, ESA, NASA

Explanation: Peering from the shadows, the Saturn-facing hemisphere of tantalizing inner moon Enceladus poses in this Cassini spacecraft image. North is up in the dramatic scene captured during November 2016 as Cassini’s camera was pointed in a nearly sunward direction about 130,000 kilometers from the moon’s bright crescent. In fact, the distant world reflects over 90 percent of the sunlight it receives, giving its surface about the same reflectivity as fresh snow. A mere 500 kilometers in diameter, Enceladus is a surprisingly active moon. Data collected during Cassini’s flybys and years of images have revealed the presence of remarkable south polar geysers and a possible global ocean of liquid water beneath an icy crust.

∞ Source: apod.nasa.gov/apod/ap190309.html

“Goldilocks” Stars May Be “Just Right” for Finding Habitable Worlds

NASA – Goddard Space Flight Center logo.

March 8, 2019

Scientists looking for signs of life beyond our solar system face major challenges, one of which is that there are hundreds of billions of stars in our galaxy alone to consider. To narrow the search, they must figure out: What kinds of stars are most likely to host habitable planets?

A new study finds a particular class of stars called K stars, which are dimmer than the Sun but brighter than the faintest stars, may be particularly promising targets for searching for signs of life.

Image above: This is an artist’s concept of a planet orbiting in the habitable zone of a K star. Image Credits: NASA Ames/JPL-Caltech/Tim Pyle.

Why? First, K stars live a very long time — 17 billion to 70 billion years, compared to 10 billion years for the Sun — giving plenty of time for life to evolve. Also, K stars have less extreme activity in their youth than the universe’s dimmest stars, called M stars or “red dwarfs.”

M stars do offer some advantages for in the search for habitable planets. They are the most common star type in the galaxy, comprising about 75 percent of all the stars in the universe. They are also frugal with their fuel, and could shine on for over a trillion years. One example of an M star, TRAPPIST-1, is known to host seven Earth-size rocky planets.

But the turbulent youth of M stars presents problems for potential life. Stellar flares – explosive releases of magnetic energy – are much more frequent and energetic from young M stars than young Sun-like stars. M stars are also much brighter when they are young, for up to a billion years after they form, with energy that could boil off oceans on any planets that might someday be in the habitable zone.

“I like to think that K stars are in a ‘sweet spot’ between Sun-analog stars and M stars,” said Giada Arney of NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

Arney wanted to find out what biosignatures, or signs of life, might look like on a hypothetical planet orbiting a K star. Her analysis is published in the Astrophysical Journal Letters.

Scientists consider the simultaneous presence of oxygen and methane in a planet’s atmosphere to be a strong biosignature because these gases like to react with each other, destroying each other. So, if you see them present in an atmosphere together, that implies something is producing them both quickly, quite possibly life, according to Arney.

However, because planets around other stars (exoplanets) are so remote, there needs to be significant amounts of oxygen and methane in an exoplanet’s atmosphere for it to be seen by observatories at Earth. Arney’s analysis found that the oxygen-methane biosignature is likely to be stronger around a K star than a Sun-like star.

Arney used a computer model that simulates the chemistry and temperature of a planetary atmosphere, and how that atmosphere responds to different host stars. These synthetic atmospheres were then run through a model that simulates the planet’s spectrum to show what it might look like to future telescopes.

“When you put the planet around a K star, the oxygen does not destroy the methane as rapidly, so more of it can build up in the atmosphere,” said Arney. “This is because the K star’s ultraviolet light does not generate highly reactive oxygen gases that destroy methane as readily as a Sun-like star.”

This stronger oxygen-methane signal has also been predicted for planets around M stars, but their high activity levels might make M stars unable to host habitable worlds. K stars can offer the advantage of a higher probability of simultaneous oxygen-methane detection compared to Sun-like stars without the disadvantages that come along with an M star host.

Additionally, exoplanets around K stars will be easier to see than those around Sun-like stars simply because K stars are dimmer. “The Sun is 10 billion times brighter than an Earthlike planet around it, so that’s a lot of light you have to suppress if you want to see an orbiting planet. A K star might be ‘only’ a billion times brighter than an Earth around it,” said Arney.

Arney’s research also includes discussion of which of the nearby K stars may be the best targets for future observations. Since we don’t have the ability to travel to planets around other stars due to their enormous distances from us, we are limited to analyzing the light from these planets to search for a signal that life might be present. By separating this light into its component colors, or spectrum, scientists can identify the constituents of a planet’s atmosphere, since different compounds emit and absorb distinct colors of light.

“I find that certain nearby K stars like 61 Cyg A/B, Epsilon Indi, Groombridge 1618, and HD 156026 may be particularly good targets for future biosignature searches,” said Arney.

Related links:

Exoplanets: https://www.nasa.gov/content/the-search-for-life

Goddard Space Flight Center (GSFC): https://www.nasa.gov/centers/goddard/home/index.html

Image (mentioned), Text, Credits: NASA/Goddard Space Flight Center, Bill Steigerwald.

Greetings, Orbiter.chArchive link

SpaceX Crew Dragon Undock from ISS and Splashes Down in Atlantic Ocean

SpaceX – COTS C-1 Mission patch.

March 8, 2019

Image above: The uncrewed SpaceX Crew Dragon spacecraft just moments after undocking from the International Space Station. Image Credit: NASA TV.

SpaceX’s Crew Dragon returned to Earth with a splash in the Atlantic Ocean off Florida’s eastern shore at 8:45 a.m. EST, completing an end-to-end flight test to demonstrate most of the capabilities of its crew transportation system to the International Space Station as part of NASA’s Commercial Crew Program.

Crew Dragon undocking and departure

The mission, known as Demo-1, is a critical step for NASA and SpaceX to demonstrate the ability to safely fly missions with NASA astronauts to the orbital laboratory.

Image above: Crew Dragon spacecraft on it’s way back to Earth after undocking from the International Space Station at 2:32 am EST on March 8, 2019. Image Credit: NASA TV.

The Crew Dragon launched March 2 from NASA’s Kennedy Space Center in Florida. It was the first commercially-built and operated American crew spacecraft and rocket to launch from American soil on a mission to the space station and autonomously dock to the station. To complete the docking, both the station and Crew Dragon’s adapters used the new international docking standard.

Crew Dragon deorbit and splashdown in the Atlantic Ocean

Crew Dragon is returning to Earth some critical research samples from science investigations conducted to enable human exploration farther into space and develop and demonstrate in the U.S. ISS National Laboratory new technologies, treatments, and products for improving life on Earth.

Also traveling aboard the spacecraft is an anthropomorphic test device named Ripley outfitted with sensors to provide data about potential effects on humans traveling in Crew Dragon.

Image above: SpaceX’s Crew Dragon splashes down in the Atlantic Ocean after successful Demo-1 flight on March 8, 2019. Image Credit: NASA TV.

SpaceX’s recovery ship, Go Searcher, is equipped with a crane to lift Crew Dragon out of the water and onto the main deck of the ship within an hour after splashdown.

NASA and SpaceX still have work to do to review the systems and flight data to validate the spacecraft’s performance and prepare it to fly astronauts. Already planned upgrades, additional qualification testing, and an in-flight abort test will occur before NASA astronauts Bob Behnken and Doug Hurley will climb aboard for Demo-2, the crewed flight test to the International Space Station that is necessary to certify Crew Dragon for routine operational missions.

Crew Dragon’s splashdown in the Atlantic was almost 50 years after the return of Apollo 9 on March 13, 1969, the last human spacecraft to return to the waters off the East Coast.

Related article:

Crew Dragon Set for Friday Splashdown Amid Space Physics Research

Related links:

Expedition 58: https://www.nasa.gov/mission_pages/station/expeditions/expedition58/index.html

SpaceX Crew Dragon: https://blogs.nasa.gov/commercialcrew

Commercial Crew Program: https://www.nasa.gov/exploration/commercial/crew/index.html

Space Station Research and Technology: https://www.nasa.gov/mission_pages/station/research/index.html

International Space Station (ISS): https://www.nasa.gov/mission_pages/station/main/index.html

Images (mentioned), Video, Text, Credits: NASA/Norah Moran/NASA TV/SciNews.

Best regards, Orbiter.chArchive link

Hubble’s Dazzling Display of 2 Colliding Galaxies

NASA – Hubble Space Telescope patch.

March 8, 2019

Located in the constellation of Hercules, about 230 million light-years away, NGC 6052 is a pair of colliding galaxies. They were first discovered in 1784 by William Herschel and were originally classified as a single irregular galaxy because of their odd shape. However, we now know that NGC 6052 actually consists of two galaxies that are in the process of colliding. This particular image of NGC 6052 was taken using the Wide Field Camera 3 on the NASA/ESA Hubble Space Telescope.

A long time ago gravity drew the two galaxies together into the chaotic state we now observe. Stars from within both of the original galaxies now follow new trajectories caused by the new gravitational effects. However, actual collisions between stars themselves are very rare as stars are very small relative to the distances between them (most of a galaxy is empty space). Eventually the galaxies will fully merge to form a single, stable galaxy.

Our own galaxy, the Milky Way, will undergo a similar collision in the future with our nearest galactic neighbor, the Andromeda galaxy. However, this is not expected to happen for around 4 billion years.

This object was previously observed by Hubble with its old Wide Field and Planetary Camera 2 (WFPC2). That image was released in 2015.

Hubble Space Telescope (HST)

For more information about Hubble, visit:




Image, Animation, Credits: ESA/Hubble & NASA, A. Adamo et al./Text Credits: ESA (European Space Agency)//NASA/Rob Garner.

Greetings, Orbiter.chArchive link

Changing Identities Where you grew up, where you moved to and…

Changing Identities

Where you grew up, where you moved to and where you live now have all shaped who you are. Cells are much the same, especially during development when they travel to their final destinations, exposing themselves to different microenvironments. Researchers investigate this process in kidney progenitor cells using sections of kidney tissue from mice (pictured). Some progenitor cells (white) mature into cells of the nephrons, the functional units of the kidney, while others maintain the pool of progenitors. The team fluorescently tagged Wnt4 (green), an early marker of maturing progenitor cells, which is switched on when these cells leave their ‘home’, where they normally reside in the kidney during development. They found through random cell movements, some of these cells returned home and were then able to switch off Wnt4. This highlights how flexible the identity of these cells is in response to the microenvironment they find themselves in.

Written by Lux Fatimathas

You can also follow BPoD on Instagram, Twitter and Facebook

Archive link

Meteor Activity Outlook for March 9-15, 2019

Yes Matilda, there are fireballs in the southern hemisphere. This is a good example taken by Steve Traynor from Cherbourg, Queensland, Australia on March 18, 2018. This fireball, with a notable flare, travels among the stars of Chamaeleon and Mensa in the deep southern sky. The notable cluster in the upper right corner is the eta Carina complex. The southern celestial pole lies between the fireball and the top of the pole. © Steve Traynor

During this period the moon will reach its first quarter phase on Thursday March 14th. At this time the half-illuminated moon will be located 90 degrees east of the sun and will set near 0200 local daylight saving time (DST) as seen from mid-northern latitudes. This weekend the waxing crescent moon will set during the late evening hours and will not interfere with the more active morning hours. Hourly meteor rates for evening observers this week is near 3 as seen from mid-northern latitudes (45N) and 4 as seen from tropical southern locations (25S). For morning observers the estimated total hourly rates should be near 8 as seen from mid-northern latitudes and 11 from the southern tropics. The actual rates will also depend on factors such as personal light and motion perception, local weather conditions, alertness and experience in watching meteor activity. Evening rates are slightly reduced during this period due to moonlight. Note that the hourly rates listed below are estimates as viewed from dark sky sites away from urban light sources. Observers viewing from urban areas will see less activity as only the brighter meteors will be visible from such locations.

The radiant (the area of the sky where meteors appear to shoot from) positions and rates listed below are exact for Saturday night/Sunday morning March 9/10 . These positions do not change greatly day to day so the listed coordinates may be used during this entire period. Most star atlases (available at science stores and planetariums) will provide maps with grid lines of the celestial coordinates so that you may find out exactly where these positions are located in the sky. A planisphere or computer planetarium program is also useful in showing the sky at any time of night on any date of the year. Activity from each radiant is best seen when it is positioned highest in the sky, either due north or south along the meridian, depending on your latitude. It must be remembered that meteor activity is rarely seen at the radiant position. Rather they shoot outwards from the radiant so it is best to center your field of view so that the radiant lies near the edge and not the center. Viewing there will allow you to easily trace the path of each meteor back to the radiant (if it is a shower member) or in another direction if it is a sporadic. Meteor activity is not seen from radiants that are located far below the horizon. The positions below are listed in a west to east manner in order of right ascension (celestial longitude). The positions listed first are located further west therefore are accessible earlier in the night while those listed further down the list rise later in the night.

Radiant Positions at 8:00pm Local Daylight Saving Time

Radiant Positions at 1:00am Local Daylight Saving Time

Radiant Positions at 6:00am Local Daylight Saving Time

These sources of meteoric activity are expected to be active this week.

The center of the large Anthelion (ANT) radiant is currently located at 12:08 (182) -01. This position lies in western Virgo, 2 degrees west of the 4th magnitude star known as Zaniah (eta Virginis). Due to the large size of this radiant, Anthelion activity may also appear from eastern Leo, and Crater as well as Virgo. This radiant is best placed near 0200 DST, when it lies on the meridian and is located highest in the sky. Rates at this time should be near 2 per hour no matter your location. With an entry velocity of 30 km/sec., the average Anthelion meteor would be of slow velocity.

The xi Herculids (XHE) were discovered by Sirko Molau and Javor Kac of the International Meteor Organization using video data from the IMO network. These meteors are active from March 9-13 with maximum activity occurring on the 11th. The current radiant position lies near 17:12 (258) +48, which lies in northern Hercules, 5 degrees southwest of the 3rd magnitude star known as Rastaban (beta Draconis). Rates are expected to be 1 per hour as seen from the northern hemisphere and less than 1 as seen from south of the equator. These meteors are best seen during the last dark hour of the morning when the radiant lies highest above the horizon in a dark sky. At 35 km/sec. this source would produce meteors of average velocities.

As seen from the mid-northern hemisphere (45N) one would expect to see approximately 5 sporadic meteors per hour during the last hour before dawn as seen from rural observing sites. Evening rates would be near 1 per hour. As seen from the tropical southern latitudes (25S), morning rates would be near 9 per hour as seen from rural observing sites and 3 per hour during the evening hours. Locations between these two extremes would see activity between the listed figures. Evening rates are slightly reduced during this period due to moonlight.

RA (RA in Deg.) DEC Km/Sec Local Daylight Saving Time North-South
Anthelion (ANT) 11:16 (169) +04 30 02:00 2 – 2 II
xi Herculids (XHE) Mar 11 17:12 (258) +48 35 07:00 1 – <1 IV

Source link


    Солнечное затмение 14 декабря 2020 года  — полное  солнечное затмение  142  сароса , которое лучше всего будет видно в юго-восточной час...