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The Earthrise image

beamed from Apollo 8, 176,000 miles away,

to the Mission Operations Control Room in Houston.


Credit NASA/Johnson Space Center


Apollo 8’s Earthrise: The Shot Seen Round the World

Half a century ago today,

a photograph from the moon

helped humans rediscover Earth.


Dec. 21, 2018



















Control Room - 10ft x 10ft Wind Tunnel


One of three control panels in the control room

of the Lewis Unitary Plan Wind Tunnel.


The tunnel model (top center)

shows position of the valves

that control the operating cycle of the tunnel.


The TV monitor screens can be connected

to any of 3 closed-circuit TV cameras

used to monitor tunnel components.


NASA Center: Glenn Research Center

Image # : C1956-40250

Date : 10/17/1955

Reference Numbers

Center: GRC

Center Number: C1956-40250

GRIN DataBase Number: GPN-2000-000598

Creator/Photographer: Martin Brown

Great Images in NASA
































National Aeronautics and Space Administration    NASA        USA































NASA > Planet quest - The search for another Earth







Nasa marks 50 years of space photography - in pictures        29 December 2012


It's half a century

since Mariner 2 swept past Venus

at a distance of 22,000 miles,

and this year's stunning pictures

from across the solar system

show how much technology

has advanced







Astronomy Picture of the Day Archive






NASA Photography from the NASA Photography Office

These official NASA photographs

are being made available via Flickr

and showcase

what is making news across the agency.






Dryden Photo Gallery

This collection contains photos

of many of the unique research aircraft flown

at NASA Dryden Flight Research Center

at Edwards, California.


These images

date from the 1940s to the present.






NASA Voyager ships







exoplanets > NASA’s TESS Spacecraft        USA

watch?v=AxSqMdEA5M8 - NYT - 16 April 2018





space capsule / NASA's Stardust spacecraft









Nasa scientist





NASA's mission control in Houston / Mission Control Center at Johnson Space Center






Apollo 13,

scheduled to be the third lunar landing,

was launched at 1313 Houston time

on Saturday, April 11, 1970


 'Houston, we have a problem'













NASA > libraries of space images






NASA > Great Images in Nasa    GRIN






NASA > Images











9 Billion-Year-Old

‘Dark Energy’ Reported


November 17, 2006

The New York Times



A strange thing happened to the universe five billion years ago. As if God had turned on an antigravity machine, the expansion of the cosmos speeded up, and galaxies began moving away from one another at an ever faster pace.

Now a group of astronomers using the Hubble Space Telescope have discovered that billions of years before this mysterious antigravity overcame cosmic gravity and sent the galaxies scooting apart like muscle cars departing a tollbooth, it was already present in space, affecting the evolution of the cosmos.

“We see it doing its thing, starting to fight against ordinary gravity,” Adam Riess of the Space Telescope Science Institute said about the antigravity force, known as dark energy. He is the leader of a team of “dark energy prospectors,” as he calls them, who peered back nine billion years with the Hubble and were able to discern the nascent effects of antigravity. The group reported their observations at a news conference yesterday and in a paper to be published in The Astrophysical Journal.

The results, Dr. Riess and others said, provide clues and place new limits on the nature of dark energy, a mystery that has thrown physics and cosmology into turmoil over the last decade.

“It gives us the ability to look at changes in dark energy,” he said in an interview. “Previously, we knew nothing about that. That’s really exciting.”

The data suggest that, in fact, dark energy has changed little, if at all, over the course of cosmic history. Though hardly conclusive, that finding lends more support to what has become the conventional theory, that the source of cosmic antigravity is the cosmological constant, a sort of fudge factor that Einstein inserted into his cosmological equations in 1917 to represent a cosmic repulsion embedded in space.

Although Einstein later abandoned the cosmological constant, calling it a blunder, it would not go away. It is the one theorized form of dark energy that does not change with time.

Sean Carroll, a cosmologist at the California Institute of Technology who was not on the team, said: “Had they found the evolution was not constant, that would have been an incredibly earthshaking discovery. They looked where no one had been able to look before.”

The paper by Dr. Riess and his colleagues represents a sort of progress report from the dark side, where astrophysicists have found themselves more and more as they try to understand what is happening to the universe.

This encounter with the invisible began eight years ago, when two competing teams of astronomers were using exploding stars known as Type 1a supernovas as cosmic distance markers to determine the fate of the universe.

Ever since the Big Bang 14 billion years ago, the galaxies and the rest of the universe have been flying apart like a handful of pebbles tossed in the air. Astronomers reasoned that gravity would be slowing the expansion, and the teams were trying to find out by how much and, thus, determine whether all would collapse one day into a “big crunch” or expand forever.

Instead, to their surprise, the two teams, one led by Saul Perlmutter of the University of California, Berkeley, and the other by Brian Schmidt of the Mount Stromlo and Siding Spring Observatories in Australia, found that the universe was speeding up instead of slowing down.

But the ground-based telescopes that the two teams used could track supernovas to distances of just seven billion light-years, corresponding to half the age of the universe, and the effect could have been mimicked by dust or a slight change in the nature of the supernova explosions.

Since then, Dr. Riess, who was a member of Dr. Schmidt’s team, and his colleagues have used the Hubble telescope to prospect for supernovas and dark energy farther out in space or back in time.

The new results are based on observations of 23 supernovas that are more than eight billion years in the past, before dark energy came to dominate the cosmos. The spectra of those distant supernovas, Dr. Riess reported, appear to be identical to those closer and more recent examples. By combining the supernova results with data from other experiments like the NASA Wilkinson Microwave Anisotropy Probe, Dr. Riess and his colleagues could begin to address the evolution of dark energy.

“That’s one of the $64,000 questions,” he said. “Is dark energy changing?”

So far, he said, the results are consistent with the cosmological constant, but other answers are also possible. The possibility that it is the cosmological constant is a mixed blessing. Physicists concede that they do not understand it.

Dr. Carroll of Caltech said, “Dark energy makes us nervous.”

Einstein invented his constant to explain why the universe does not collapse. After he abandoned it, the theory was resuscitated by quantum mechanics, which showed that empty space should be bubbling with staggering amounts of repulsive energy. The possibility that it really exists in the tiny amounts measured by the astronomers has flummoxed physicists and string theorists.

Because it is a property of empty space, the overall force of Einstein’s constant grows in proportion as the universe expands, until it overwhelms everything. Other theories of dark energy like strange force fields called quintessence or modifications to Einstein’s theory of gravity can change in more complicated ways, rising, falling or reversing effects.

Astronomers characterize the versions of dark energy by their so-called equation of state, the ratio of pressure to density, denoted by the letter w. For the cosmological constant, w is minus one.

Dr. Riess and his group used their data to make the first crude measurement of this quantity as it stood nine billion years ago. The answer, he said, was minus one — the magic number — plus or minus about 50 percent. By comparison for more recent times, with many more supernovas observable and thus more data, the value is minus one with an uncertainty of about 10 percent.

“If at one point in history it’s not minus one,” Dr. Riess said, “then we have killed the very best explanation.”

Getting to the precision needed to kill or confirm Einstein’s constant, however, will be very difficult, he conceded. One of the biggest sources of uncertainty is the fact that the Type 1a explosions are not completely uniform, introducing scatter into the observations.

The Hubble is the sole telescope that can pursue supernova explosions deeply enough to chart the early days of dark energy. The recent announcement that the National Aeronautics and Space Administration will send astronauts to maintain and refurbish the Hubble once again, enabling it to keep performing well into the next decade, is a lift for Dr. Riess’s project. A new camera could extend observations to 11 billion or 12 billion years back.

9 Billion-Year-Old ‘Dark Energy’ Reported,










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