Day: July 10, 2022

Drawing back the curtain to a photo gallery unlike any other, NASA will soon present the first full-color images from its James Webb Space Telescope, a revolutionary apparatus designed to peer through the cosmos to the dawn of the universe.

The highly anticipated July 12 unveiling of pictures and spectroscopic data from the newly operational observatory follows a six-month process of remotely unfurling various components, aligning mirrors and calibrating instruments.

With Webb now finely tuned and fully focused, astronomers will embark on a competitively selected list of science projects exploring the evolution of galaxies, the life cycles of stars, the atmospheres of distant exoplanets and the moons of our outer solar system.

The first batch of photos, which have taken weeks to process from raw telescope data, are expected to offer a compelling glimpse at what Webb will capture on the science missions that lie ahead.

NASA on Friday posted a list of the five celestial subjects chosen for its showcase debut of Webb, built for the U.S. space agency by aerospace giant Northrop Grumman Corp.

Among them are two nebulae – enormous clouds of gas and dust blasted into space by stellar explosions that form nurseries for new stars – and two sets of galaxy clusters.

One of those, according to NASA, features objects in the foreground so massive that they act as “gravitational lenses,” a visual distortion of space that greatly magnifies the light coming from behind them to expose even fainter objects farther away and further back in time. How far back and what showed up on camera remains to be seen.

NASA will also publish Webb’s first spectrographic analysis of an exoplanet, revealing the molecular signatures from patterns of filtered light passing through its atmosphere. The exoplanet in this case, roughly half the mass of Jupiter, is more than 1,100 light years away. A light year is the distance light travels in a year – 9.5 trillion kilometers.

‘Moved me as a scientist … as a human being’

All five of the Webb’s introductory targets were previously known to scientists. One of them, the galaxy group 290 million light-years from Earth known as Stephan’s Quintet, was first discovered in 1877.

But NASA officials promise Webb’s imagery captures its subjects in an entirely new light, literally.

“What I have seen moved me as a scientist, as an engineer and as a human being,” NASA deputy administrator Pam Melroy, who has reviewed the images, told reporters during a June 29 news briefing.

Klaus Pontoppidan, a Webb project scientist at the Space Telescope Science Institute in Baltimore, where mission control engineers operate the telescope, has promised the first pictures would “deliver a long-awaited ‘wow’ for astronomers and the public.”

The $9 billion infrared telescope, the largest and most complex astronomical observatory ever sent to space, was launched on Christmas Day from French Guiana, on the northeastern coast of South America.

A month later, the 6,350-kilogram instrument reached its gravitational parking spot in solar orbit, circling the sun in tandem with Earth more than 1.6 million kilometers from home.

Webb, which views its subjects chiefly in the infrared spectrum, is about 100 times more sensitive than its 30-year-old predecessor, the Hubble Space Telescope, which orbits Earth from 547 kilometers away and operates mainly at optical and ultraviolet wavelengths.

The larger light-collecting surface of Webb’s primary mirror – an array of 18 hexagonal segments of gold-coated beryllium metal – enables it to observe objects at greater distances, thus further back in time, than Hubble or any other telescope.

Its infrared sensitivity allows it to detect light sources that would otherwise be hidden in the visible spectrum by dust and gas.

Taken together, these features are expected to transform astronomy, providing the first glimpse of infant galaxies dating to just 100 million years after the Big Bang, the theoretical flashpoint that set the expansion of the known universe in motion an estimated 13.8 billion years ago.

Webb’s instruments also make it ideal to search for signs of potentially life-supporting atmospheres around scores of newly documented planets orbiting distant stars and to observe worlds much closer to home, such as Mars and Saturn’s icy moon Titan.

Besides a host of studies already lined up for Webb, the telescope’s most revolutionary findings may prove to be those that have yet to be anticipated.

Such was the case in Hubble’s surprising discovery, through observations of distant supernovas, that the expansion of the universe is accelerating, rather than slowing down, opening a new field of astrophysics devoted to a mysterious phenomenon scientists call dark energy.

The Webb telescope is an international collaboration led by NASA in partnership with the European and Canadian space agencies.

Source: Voice of America

The Yellowstone National Park area’s weather forecast the morning of June 12 seemed fairly tame: warmer temperatures and rain showers would accelerate mountain snow melt and could produce “minor flooding.” A National Weather Service bulletin recommended moving livestock from low-lying areas but made no mention of danger to people.

By nightfall, after several inches of rain fell on a deep spring snowpack, there were record-shattering floods.

Torrents of water poured off the mountains. Swollen rivers carrying boulders and trees smashed through Montana towns over the next several days. The flooding swept away houses, wiped out bridges and forced the evacuation of more than 10,000 tourists, park employees and residents near the park.

As a cleanup expected to last months grinds on, climate experts and meteorologists say the gap between the destruction and what was forecast underscores a troublesome aspect of climate change: Models used to predict storm impacts do not always keep up with increasingly devastating rainstorms, hurricanes, heat waves and other events.

“Those rivers had never reached those levels. We literally were flying blind not even knowing what the impacts would be,” said Arin Peters, a senior hydrologist with the National Weather Service.

Hydrologic models used to predict flooding are based on long-term, historical records. But they do not reflect changes to the climate that emerged over the past decade, said meteorologist and Weather Underground founder Jeff Masters.

“Those models are going to be inadequate to deal with a new climate,” Masters said.

Another extreme weather event where the models came up short was Hurricane Ida, which slammed Louisiana last summer and then stalled over the Eastern Seaboard — deluging parts of Pennsylvania, New Jersey and New York with unprecedented rainfall that caused massive flooding.

The weather service had warned of a “serious situation” that could turn “catastrophic,” but the predicted of 3 to 6 inches (8 to 15 centimeters) of rain for New York, New Jersey and Pennsylvania was far short of the 9 to 10 inches (23 to 25 centimeters) that fell.

The deadly June 2021 heat wave that scorched the Pacific Northwest offered another example. Warmer weather had been expected, but not temperatures of up to 116 degrees (47C degrees) that toppled previous records and killed an estimated 600 or more people in Oregon, Washington state and western Canada.

The surprise Yellowstone floods prompted a nighttime scramble to close off roads and bridges getting swept away by the water, plus rushed evacuations that missed some people. No one died, somewhat miraculously, as more than 400 homes were damaged or destroyed.

As rockslides caused by the rainfall started happening in Yellowstone, park rangers closed a heavily used road between the town of Gardiner and the park headquarters in Mammoth Hot Springs, Wyoming. The road was later washed out in numerous places.

The rain and snowmelt was “too much too fast and you just try to stay out of the way,” Yellowstone Deputy Chief Ranger Tim Townsend said.

If the road hadn’t been closed, “we probably would have had fatalities, unquestionably” park Superintendent Cam Sholly said.

“The road looks totally fine and then it’s like an 80-foot drop right into the river,” Sholly said.

Interior Secretary Deb Haaland was scheduled to visit Yellowstone on Friday to survey the damage and ongoing repairs.

Within a matter of hours on June 12, Rock Creek, which runs through the city of Red Lodge and normally is placid and sometimes just ankle deep, became a raging river. When the weather service issued a flood warning for the creek, the water already had surged over its banks and begun to knock down bridges.

By the time the warning was sent, “we already knew it was too late,” said Scott Williams, a commissioner for Carbon County, Montana, which borders Yellowstone.

Red Lodge resident Pam Smith was alerted to the floods by something knocking around in her basement before dawn. It was her clothes dryer, floating in water pouring through the windows.

Smith says her partner keeps track of the weather on his computer and they were aware rain was coming and that the creek was running high. But they were not aware of flooding threat when they went to bed the night before, she said.

In a scramble to save belongings including her violins, the music teacher slipped on the wet kitchen floor and fell, shattering a bone in her arm. Smith recalls biting back tears and trudging through floodwaters with her partner and 15-year-old granddaughter to reach their pickup truck and drive to safety.

“I went blank,” Smith said. “I was angry and like, ‘Why didn’t anybody warn us? Why was there no knock on the door? Why didn’t the police come around and say there’s flooding, you need to get out?'”

Local authorities say sheriff’s deputies and others knocked on doors in Red Lodge and a second community that flooded. But they acknowledged not everyone was reached as numerous rivers and streams overflowed, swamping areas never known previously to flood.

While no single weather event can be conclusively tied to climate change, scientists said the Yellowstone flooding was consistent with changes already documented around the park as temperatures warm.

Those changes include less snowfall in mid-winter and more spring precipitation — setting the stage for flash floods when rains fall on the snow, said Montana State University climate scientist Cathy Whitlock.

Warming trends mean spring floods will increase in frequency — even as the region suffers from long-term drought that keeps much of the rest of the year dry, she said.

Masters and other experts noted that computer modeling of storms has become more sophisticated and is generally more accurate than ever. But extreme weather by its nature is hard to predict, and as such events happen more frequently there will be many more chances for forecasters to get it wrong.

The rate of the most extreme rainstorms in some areas has increased up to a factor of five, Masters said. So an event with a 1% chance of happening in any given year — commonly referred to as a “one in 100-year” event — would have an approximately 5% chance of happening, he said.

“We are literally re-writing our weather history book,” said University of Oklahoma Meteorology Professor Jason Furtado.

That has widespread implications for local authorities and emergency officials who rely on weather bulletins to guide their disaster response approaches. If they’re not warned, they can’t act.

But the National Weather Service also strives to avoid undue alarm and maintain public trust. So if the service’s models show only a slim chance of disaster, that information can get left out of the forecast.

Weather service officials said the agency’s actions with the Yellowstone flooding will be analyzed to determine if changes are needed. They said early warnings that river levels were rising did help officials prepare and prevent loss of life, even if their advisories failed to predict the severity.

Computer-based forecasting models are regularly updated to account for new meteorological trends due to climate change, Peters said. Even with those refinements, events like the Yellowstone flooding still are considered low-probability and so often won’t make it into forecasts based on what the models say is most likely to occur.

“It’s really difficult to balance that feeling that you’ve got that this could get really bad, but the likelihood of it getting really bad is so small,” Peters said. He added that the dramatic swing from drought to flood was hard even for meteorologists to reconcile and called it “weather whiplash.”

To better communicate the potential for extreme weather, some experts say the weather service needs to change its forecasts to inform the public about low probability hazardous events. That could be accomplished through more detailed daily forecasts or some kind of color-coded system for alerts.

“We’ve been slow to provide that information,” North Carolina State University atmospheric scientist Gary Lackmann said. “You put it on people’s radars and they could think about that and it could save lives.”

Source: Voice of America