Space

2021-04-18

The mystery of the twin quasars

Detective Albert Einstein predicted this find. The solution is gravitational lensing.

From an article in astronomy.com.

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2021-04-18

A rather nearby antimatter fountain

At the centre of our galaxy is an .... anti-matter fountain, where hundreds of billions of tons of positrons are being annihilated every second.

Researchers have more or less ruled out the usual suspects.

From an article in astronomy.com.

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2011-08-19

Sample return mission from an asteroid

...expected to have enough organics to be a plausible source (not this very asteroid, of course) of seeding life on Earth.

Hmm, am I the only person who thinks of The Andromeda Strain? ;-)

Originally shared by Michael Interbartolo III on Google+

NASA selects OSIRIS-REx as New Frontiers Mission

In a few years a NASA spacecraft will seek the building blocks of life in a shovelful of asteroid dirt. The OSIRIS-REx spacecraft, targeted for launch in September 2016, will intercept asteroid 1999 RQ36, orbit it for a year, and then reach out a robotic arm to touch its surface.

"We call it 'touch and go,'" explains principal investigator Michael Drake of the University of Arizona. "OSIRIS-REx will approach the surface at 0.1 m/sec (only 0.2 mph, less than a tenth of walking pace) and, without landing, stretch out its arm equipped with a sample collector. We'll simply agitate the asteroid's surface with ultra-pure nitrogen to stir up material for capture."

Asteroids appear to be as lifeless as Yorick's skull, yet material captured from 1999 RQ36 could hold clues to life's origin on Earth.

Some scientists believe Earth's surface was sterilized2 soon after the planet was formed some 4.5 billion years ago. Planetoids and other debris left over from the genesis of planets pummeled Earth, turning it into a cratered wasteland. The tremendous kinetic energy from the collisions heated Earth to the boiling point.

"Earth at 'time zero' had a steam atmosphere that was wrung out to make a boiling hot ocean," says Drake. "Imagine standing on a lava lake in Hawaii, but it's a planet-wide, 600 mile deep lake. You and everything else, including any organics and any one-celled organisms, would be converted to carbon dioxide and water. Gone."

In this scenario, an infusion of organics from elsewhere might be required to ignite life here. The building blocks for life on our planet may have come, at least in part, from asteroids.

"Observations by ground-based telescopes suggest that asteroid 1999 RQ36 has a wealth of carbon-based compounds, but we don't know exactly what is there. Are there amino acids? To find out, we need to bring a sample home where we have sophisticated, exquisitely precise instruments, plus the ability to react to new discoveries."

Obtaining that sample is a key part of OSIRIS-REx's mission.

OSIRIS-REx's sampling arm stirs up the topsoil using pure nitrogen. [97 MB movie]

Upon reaching 1999 RQ36 in 2019, the spacecraft's suite of cameras and instruments will spend a year photographing the asteroid and measuring its surface topography, composition, and thermal emissions while its radio provides mass and gravity field maps. This information will increase our understanding of asteroids as well as help the mission team select the most promising sample site.

Like the ancient Egyptian god Osiris, the OSIRIS-REx mission is associated with death as well as life, with both our destiny and our origin. That's because 1999 RQ36 is the Near Earth Object "Most Likely to Succeed" – in affecting our destiny, that is. It has a 1/1800 chance of hitting Earth by the 22nd century.

Evidence suggests that a 6-mile wide asteroid smashed into Earth about 65 million years ago, wiping out the dinosaurs and altering the history of life. Instead of dinosaurs prevailing, mammals flourished, evolving into humans. "We're the first species that can mitigate asteroid extinction," notes Drake. "With enough information, we can project the orbit of a threatening asteroid."

If researchers can track an NEO's precise path, they can devise a way to nudge the object out of a collision course with Earth. OSIRIS-REx wil help NASA learn to navigate near an asteroid, laying the groundwork for landing on one. That could be pretty tricky, considering asteroids like 1999 RQ36 have so little gravity.

"If you simply pushed your finger into the surface, you'd fly off into space, disappear, and never come back!"

OSIRIS-REx, however, will hang close, and its cameras will give us window seats to watch its delicate sampling maneuvers. The mission team plans near-live coverage of the operations. But the real action starts, says Drake, when the sample is returned to Earth in 2023.

Video here. [1 min 42 sec]

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2011-08-19 (G+)

Spacecraft Sees Solar Storm Engulf Earth

Awesome!

Spacecraft Sees Solar Storm Engulf Earth

August 18, 2011: For the first time, a spacecraft far from Earth has turned and watched a solar storm engulf our planet. The movie, released today during a NASA press conference, has galvanized solar physicists, who say it could lead to important advances in space weather forecasting.

“The movie sent chills down my spine,” says Craig DeForest of the Southwest Research Institute in Boulder, Colorado. "It shows a CME swelling into an enormous wall of plasma and then washing over the tiny blue speck of Earth where we live. I felt very small.”

CMEs are billion-ton clouds of solar plasma launched by the same explosions that spark solar flares. When they sweep past our planet, they can cause auroras, radiation storms, and in extreme cases power outages. Tracking these clouds and predicting their arrival is an important part of space weather forecasting.

“We have seen CMEs before, but never quite like this,” says Lika Guhathakurta, program scientist for the STEREO mission at NASA headquarters. “STEREO-A has given us a new view of solar storms.”

STEREO-A is one of two spacecraft launched in 2006 to observe solar activity from widely-spaced locations. At the time of the storm, STEREO-A was more than 65 million miles from Earth, giving it the “big picture” view other spacecraft in Earth orbit have been missing.

When CMEs first leave the sun, they are bright and easy to see. Visibility is quickly reduced, however, as the clouds expand into the void. By the time a typical CME crosses the orbit of Venus, it is a billion times fainter than the surface of the full Moon, and more than a thousand times fainter than the Milky Way. CMEs that reach Earth are almost as gossamer as vacuum itself and correspondingly transparent.

“Pulling these faint clouds out of the confusion of starlight and interplanetary dust has been an enormous challenge,” says DeForest. Indeed, it took almost three years for his team to learn how to do it. Footage of the storm released today was recorded back in December 2008, and they have been working on it ever since. Now that the technique has been perfected, it can be applied on a regular basis without such a long delay.

Alysha Reinard of NOAA’s Space Weather Prediction Center explains the benefits for space weather forecasting: “Until quite recently, spacecraft could see CMEs only when they were still quite close to the sun. By calculating a CME's speed during this brief period, we were able to estimate when it would reach Earth. After the first few hours, however, the CME would leave this field of view and after that we were 'in the dark' about its progress.”

“The ability to track a cloud continuously from the Sun to Earth is a big improvement,” she continues. “In the past, our very best predictions of CME arrival times had uncertainties of plus or minus 4 hours,” she continues. “The kind of movies we’ve seen today could significantly reduce the error bars.”

The movies pinpoint not only the arrival time of the CME, but also its mass. From the brightness of the cloud, researchers can calculate the gas density with impressive precision. Their results for the Dec. 2008 event agreed with actual in situ measurements at the few percent level. When this technique is applied to future storms, forecasters will be able to estimate its impact with greater confidence.

At the press conference, DeForest pointed out some of the movie’s highlights: When the CME first left the sun, it was cavernous, with walls of magnetism encircling a cloud of low-density gas. As the CME crossed the Sun-Earth divide, however, its shape changed. The CME “snow-plowed” through the solar wind, scooping up material to form a towering wall of plasma. By the time the CME reached Earth, its forward wall was sagging inward under the weight of accumulated gas.

The kind of magnetic transformations revealed by the movie deeply impressed Guhathakurta: “I have always thought that in heliophysics understanding the magnetic field is equivalent to the ‘dark energy’ problem of astrophysics. Often, we cannot see the magnetic field, yet it orchestrates almost everything. These images from STEREO give us a real sense of what the underlying magnetic field is doing.”

All of the speakers at today’s press event stressed that the images go beyond the understanding of a single event. The inner physics of CMEs have been laid bare for the first time—a development that will profoundly shape theoretical models and computer-generated forecasts of CMEs for many years to come.

“This is what the STEREO mission was launched to do,” concludes Guhathakurta, “and it is terrific to see it live up to that promise."

Author: Dr. Tony Phillips | Credit: Science@NASA

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2011-08-18 (G+)

Has graphene been detected in space?

Interesting!

HAS GRAPHENE BEEN DETECTED IN SPACE by the Spitzer Space Telescope?

A team of astronomers, using the Spitzer Space Telescope, have reported the first extragalactic detection of the C70 fullerene molecule, and the possible detection of planar C24 (“a piece of graphene”) in space. Letizia Stanghellini and Richard Shaw, members of the team at the National Optical Astronomy Observatory in Tucson, Arizona describe how collisional shocks powered by the winds from old stars in planetary nebulae could be responsible for the formation of fullerenes (C60 and C70) and graphene (planar C24). The team is led by Domingo Aníbal García-Hernández of the Instituto de Astrofísica de Canarias in Spain and includes international astronomers and biochemists.

Planetary nebulae originate from stars similar to our sun that have reached the end of their lives and are shedding shells of gas into space. In this case, the planetary nebulae are located in the Magellanic Clouds, two satellite galaxies to our own Milky Way, that are best seen from the Southern Hemisphere. At the distance of the Magellanic Clouds, planetary nebula appear as small fuzzy blobs. However, unlike planetaries in our own Milky Way Galaxy whose distances are very uncertain, the distance to planetaries in the Magellanic Clouds can be determined to better than 5%. With such accurate distances, the research team determined the true luminosity of the stars and confirmed that the objects are indeed planetary nebulae and not some other object in the astrophysical zoo.

Fullerenes, or Buckyballs, are known from laboratory work on earth, and have many interesting and important properties. Fullerenes consist of carbon atoms arranged in a three dimensional sphere similar to the geodesic domes popularized by Buckminster Fuller. The C70 fullerene can be compared with a rugby ball, while C60 is compared to a soccer ball. Both of these molecules have been detected in the sample. Graphene (planar C24) is a flat sheet of carbon atoms, one atom thick, that has extraordinary strength, conductivity, elasticity and thinness. Cited as the thinnest substance known, graphene was first synthesized in the lab in 2004 by Geim and Novoselov for which they received the 2010 Nobel Prize in physics. “If confirmed with laboratory spectroscopy – something that is almost impossible with the present techniques – this would be the first detection of graphene in space” said team member García-Hernández.

The team has proposed that fullerenes and graphene are formed from the shock-induced (i.e., grain-grain collisions) destruction of hydrogenated amorphous carbon grains (HACs). Such collisions are expected in the stellar winds emanating from planetary nebulae, and this team sees evidence for strong stellar winds in the ultraviolet spectra of these stars. “What is particularly surprising is that the existence of these molecules does not depend on the stellar temperature, but on the strength of the wind shocks” says Stanghellini.

The Small Magellanic cloud is particularly poor in metals (any element besides hydrogen and helium, in astronomers’ parlance) but this sort of environment favors the evolution of carbon rich-planetary nebulae, which turns out to be a favorable place for complex carbon molecules. The challenge has been to extract the evidence for graphene (planar C24) from Spitzer data. “The Spitzer Space Telescope has been amazingly important for studying complex organic molecules in stellar environments” says Stanghellini. “We are now at the stage of not only detecting fullerenes and other molecules, but starting to understand how they form and evolve in stars.” Shaw adds “We are planning ground-based follow up through the NOAO system of telescopes. We hope to find other molecules in planetary nebulae where fullerene has been detected to test some physical processes that might help us understand the biochemistry of life.”

The accompanying image includes an artist’s conception of these molecules superimposed on the well known Helix Nebula. The smaller image shows one of the objects from this study in which fullerene has been detected in the Large Magellanic Cloud (SMP 48, from the catalog by Sanduleak, MacConnell, & Philip) The name “Planetary Nebula” was applied to these star systems because their shell of surrounding gas made them appear like the disks of Jupiter, Saturn and Uranus as observed in 18th century telescopes. The reason for this name is obvious from the modern image.

These results are presented in a paper published by the Astrophysical Journal. Letters, Volume 737, Issue 2, article id. L30 (2011) The team includes D. A. García-Hernandez, S. Iglesias-Groth, J. A. Acosta-Pulido, A. Manchado, P. García-Lario, L. Stanghellini, E. Villaver, R. A. Shaw and F. Cataldo

NOAO is operated by Association of Universities for Research in Astronomy Inc. (AURA) under a cooperative agreement with the National Science Foundation.

For more info on the Spitzer Space Telescope - http://www.spitzer.caltech.edu/

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2011-07-21

An old Google+ post:

Wow!

I remember all the grown-ups were clustered round the radio that night. We were up later than usual.

I said I could see the man in the moon. (Of course, I meant the 'face' that everyone sees). That certainly sparked an excited discussion till the truth emerged.

Originally shared by Michael Interbartolo

MAN ON THE MOON - Apollo 11 Anniversary

July 20, 1969

An estimated 1 billion people on the planet Earth are watching or listening to transmissions from the Apollo spacecraft in lunar orbit All three U.S. television networks are on live. At 1:30pm U.S. Armed Forces Network radio is on live. In lunar orbit, Mike Collins has taken the controls of the Command Ship Columbia and gently undocks from the lunar lander, the Eagle.

In train stations and bus stations, ball parks and airports the sounds coming from the moonships and the crackling static are heard around the country. Briefly, for a fleeting moment in time, the entire American nation has come together as one to follow an event- this time, not a national tragedy but a voyage of exploration: humans on their way down to the surface of an alien world.

1:40pm EDT -

“The Eagle has wings!” Cries Buzz Aldrin and Apollo moves away from the Eagle. Slowly Columbia and Eagle pull away from each other but remain in the same orbit.

Eagle Has wings.

3:12pm EDT -

Now with both craft on the back side of the Moon, the Eagle’s engine fires up and begins to break the craft down into a lower orbit. The engine fires at 10 percent thrust for 15 seconds, then is gradually increased up to some 40 percent of its 9,970 lbs of capability.

The crew is flying with their feet first, face up. The craft speeds across the barren landscape below just 60 miles up with a low point of eight miles. At that low point they are to fire up for the final descent burn, riding a rocket’s tail of hot gas towards the lunar landscape.

3:47pm EDT -

Columbia’s Mike Collins calls the ground and reports that the Eagle is “on its way down” towards the surface. At 260 miles uprange from the touchdown point, the LM’s rocket engine fires again for its final burn -or PDI (Powered Descent Initiate). Now Eagle is dropping from 50,000 feet above the Moon to a low point of 10,000 feet. The engine is powered down to 6,000 pounds of thrust. But now, at 39,000 foot altitude, things begin to go wrong.

On the instrument panel, the Caution-And-Warning System alerts the crew that they are close to radar lockup. If this happens, their radar system will be unable to guide them towards the landing site. The crew quickly resets the switches for the system, and it returns to normal.

At 9,620 feet, the craft’s computer begins to send a series of alarms to the crew. These “1202” alarms warn that the computer was becoming overloaded with data inputs that were taking too long to process. Armstrong cleared the computer’s memory and asked Houston control for a judgment call. Mission Control calls the crew: go!

Just above 2,000 feet Armstrong takes manual control of Eagle briefly to check out the flight controls. The spacecraft is snappy and responsive. Below 1,500 feet, the astronauts are now scanning the landing site below. What they see concerns them. The autopilot is bringing Eagle down into a boulder-strewn field. At 500 feet altitude, concerned that the landing site was not suitable, Armstrong reached over and took control of the spacecraft away from the autopilot and the computer: he was flying the Eagle.

Using the ascent stage thrusters, Armstrong brings the Eagle laterally across the surface looking for a landing site. At 100 feet he stops the rate of descent, the begins it again slowly.

At 30 feet, peering through a cloud of dust stirred up on the surface of the Sea of Tranquility, Aldrin calls out that Eagle has less than a minute of fuel left in its tanks. Should they abort? Peering through the clouds, Armstrong sees a smooth area through a break in the dust. He has moved more than 1,100 feet across from the original landing point as chosen by the computer. Armstrong was still looking out the window when Aldrin calls: “Contact Light!” A small light has illuminated on their instrument panel, indicating that a probe in one of the LM’s footpads has touched the alien lunar soil.

With the engine still running, the LM drops down onto the surface. Armstrong shuts off the descent engine. All is quiet .In Mission Control Capsule Communicator Charles Duke calls to the crew “we copy you down Eagle?” At first there is only static. Then Armstrong calls across the generations: “Houston, Tranquility Base here-the Eagle has landed!”.

On the east coast of the United States it was 4:18pm EDT. In Yankee Stadium in New York city 16,000 people rose to sing the National Anthem as they stopped a baseball game in progress. At Grand Central Station, the thousands of Sunday travelers cheered so loud Aldrin’s last words before touchdown were not heard. In Trafalgar Square, London announcers screamed “the Americans have done it!”. In Japan, television viewers were told "a new age has now begun". In Mission Control Houston, flight controllers come to their feet cheering, breaking a tradition of silence.

It had been nearly exactly 8 years, 2 months since John Fitzgerald Kennedy had walked up the center aisle of the U.S. House of Representatives and made the lunar landing a national goal. In his CBS News control booth, newsman Walter Cronkite cannot speak. He turns to astronaut Walter Schirra and then says: "Man on the Moon!"It is Sunday, July 20, 1969.

The mission has been accomplished...

6:00 p.m.

With everything in order, Armstrong radios a recommendation that they plan to start the EVA (Extra Vehicular Activity), earlier than originally scheduled, at about 9:OO p.m. EDT. Mission Control replies: "We will support you anytime."

10:39 p.m.

Later than proposed at 6:00 p.m., but more than five hours ahead of the original schedule, Armstrong opens the LM hatch and squeezes through the opening. It is a slow process. Strapped to his shoulders is a portable life support and communications system weighing 84 pounds on Earth, 14 on the Moon, with provision for pressurization; oxygen requirements and removal of carbon dioxide.

Armstrong moves slowly down the 10-foot, nine-step ladder. On reaching the second step, he pulls a "D-ring," within easy reach, deploying a television camera, so arranged on the LM that it will depict him to Earth as he proceeds from that point.

Down the ladder he moves and halts on the last step. "I'm at the foot of the ladder," he reports. "The LM footpads are only depressed in the surface about one or two inches. . . the surface appears to be very, very finegrained, as you get close to it, it's almost like a powder."

10:56 p.m.

Armstrong puts his left foot to the Moon. It is the first time in history that man has ever stepped on anything that has not existed on or originated from the Earth.

"That's one small step for a man, one giant leap for mankind," Armstrong radios. Aldrin is taking photographs from inside the spacecraft.

The first print made by the weight of man on the Moon is that of a lunar boot which resembles an oversized galosh.

Its soles are of silicon rubber and its 14-layer sidewalls of aluminized plastic. Specially designed for super-insulation, it protects against abrasion and has reduced friction to facilitate donning. On Earth, it weighs four pounds, nine ounces. on the Moon, 12 ounces.

Armstrong surveys his surroundings for a while and then moves out, testing himself in a gravity environment one-sixth of that on Earth. "The surface is fine and powdery," he says. "I can pick it up loosely with my toe. It does adhere in fine layers like powdered charcoal to the sole and sides of my boots. I only go in a small fraction of an inch. Maybe an eighth of an inch, but I can see the footprints of my boots and the treads in the fine sandy particles.

"There seems to be no difficulty in moving around as we suspected. It's even perhaps easier than the simulations...."

Feeling more confident, Armstrong begins making a preliminary collection of soil samples close to the landing craft. This is done with a bag on the end of a pole.

"This is very interesting," he comments. "It's a very soft surface, but here and there . . . I run into a very hard surface, but it appears to be very cohesive material of the same sort.... It has a stark beauty all its own. It's like much of the high desert of the United States."

He collects a small bagful of soil and stores it in a pocket on the left leg of his space suit. This is done early, according to plan, to make sure some of the Moon surface is returned to Earth in case the mission has to be cut short.

11:11 p.m.

After lowering a Hasselblad still camera to Armstrong, Aldrin emerges from the landing craft and backs down the ladder, while his companion photographs him.

"These rocks . . . are rather slippery," Armstrong says. The astronauts report that the powdery surface seems to fill up the fine pores on the rocks, and they tend to slide over them rather easily.

Armstrong fits a long focal length lens into position on the TV camera and trains it upon a small, stainless steel plaque on one of the legs of the landing craft. He reads: "Here men from the planet Earth first set foot on the Moon. July 1969 A.D. We came in peace for all mankind." Below the inscription are the names of the Apollo crew and President Nixon.

Armstrong next removes the TV camera from its fixed position on the LM and moves it away about 40 feet so it can cover the area in which the astronauts will operate.

As scheduled, the astronauts set up the first of three experiments. From an outside storage compartment in the LM, Aldrin removes a foot-long tube containing a roll of aluminum foil. Inside the roll is a telescoped pole that is driven into the lunar surface, after which the foil is...

...suspended from it, with the side marked "Sun" next to the Sun. Its function will be to collect the particles of "solar wind" blowing constantly through space so that they can be brought back and analyzed in the hope they will provide information on how the Sun and planets were formed.

11:41 p.m.

From a leg of the spacecraft, the astronauts take a three-by-five-foot, nylon United States flag, its top edge braced by a spring wire to keep it extended on the windless Moon and erect it on a staff pressed into the lunar surface.

Taken to the Moon are two other U.S. flags, to be brought back and flown over the houses of Congress, the flags of the 50 States, the District of Columbia and U.S. territories, the United Nations flag, as well as those of 136 foreign countries.

11:47 p.m.

Mission Control announces: "The President of the United States is in his office now and would like to say a few words to you." Armstrong replies: "That would be an honor."

11:48 p.m.

The astronauts listen as the President speaks by telephone: "Neil and Buzz. I am talking to you from the Oval Room at the White House. And this certainly has to be the most historic telephone call ever made For every American this has to be the proudest day of our lives. And for people all over the world I am sure they, too, join with Americans in recognizing what a feat this is. Because of what you have done, the heavens have become a part of man's world. As you talk to us from the Sea of Tranquillity, it inspires us to redouble our efforts to bring peace and tranquility to Earth. For one priceless moment, in the whole history of man, all the people on this Earth are truly one."

As the President finishes speaking, Armstrong replies: "Thank you, Mr. President. It's a great honor and privilege for us to be here representing not only the United States but men of peace of all nations. And with interest and a curiosity and a vision for the future. It's an honor for us to be able to participate here today."

The two astronauts stand at attention, saluting directly toward the television as the telephone conversation concludes.

Armstrong next sets up a folding table and opens on it two specimen boxes. Using tongs and the lunar scoop, a quantity of rocks and soil are picked up and sealed in the boxes, preparatory to placing them in the ascent stage of the landing craft.

Aldrin, meanwhile, opens another compartment in the ship and removes two devices to be left on the Moon, taking each out about 30 feet from the ship. One is a seismic detector, to record moonquakes, meteorite impact, or volcanic eruption, and the other a laser-reflector, a device designed to make a much more precise measurement of Earth-Moon distances than has ever been possible before.

Source: Michael Interbartolo III, NASA

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2011-07-08

Michael Interbartolo's weekly space pictures July 2011

Michael Interbartolo III, a NASA Project Manager, used to share the best space images weekly on Google+. Here are a few thumbnails from some of those posts, and his descriptive comments.

2011-07-29

"Rapture" a time-lapse video

Fantabulous. Sighhhhh.

Video by Tom Lowe. He says: My most recent timelapse video, "Rapture."

2 min 6 sec video. This is on Vimeo, higher definition, so it is likely that more bandwidth will be needed than YouTube.

At around the 1 min 25 sec mark, there is a scene in which you can see stars in the day-lit sky!

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