Scientists discover mechanism that may prevent death of cells

Washington D.C., Feb 6: An international team of astronomers has found an unusual monster galaxy that existed about 12 billion years ago when the universe was only 1.8 billion years old.

The team of astronomers was led by scientists at the University of California, Riverside.

Dubbed XMM-2599, the galaxy formed stars at a high rate and then died. Why it suddenly stopped forming stars is unclear.

"Even before the universe was 2 billion years old, XMM-2599 had already formed a mass of more than 300 billion suns, making it an ultra massive galaxy," said Benjamin Forrest, a postdoctoral researcher in the UC Riverside Department of Physics and Astronomy and the study's lead author.

"More remarkably, we show that XMM-2599 formed most of its stars in a huge frenzy when the universe was less than 1 billion years old and then became inactive by the time the universe was only 1.8 billion years old," Forrest added.

The team used spectroscopic observations from the W. M. Keck Observatory's powerful Multi-Object Spectrograph for Infrared Exploration or MOSFIRE, to make detailed measurements of XMM-2599 and precisely quantify its distance.

The study results appear in the Astrophysical Journal.

"In this epoch, very few galaxies have stopped forming stars, and none are as massive as XMM-2599," said Gillian Wilson, a professor of physics and astronomy at UCR in whose lab Forrest works.

"The mere existence of ultramassive galaxies like XMM-2599 proves quite a challenge to numerical models. Even though such massive galaxies are incredibly rare at this epoch, the models do predict them."

"The predicted galaxies, however, are expected to be actively forming stars. What makes XMM-2599 so interesting, unusual, and surprising is that it is no longer forming stars, perhaps because it stopped getting fuel or its black hole began to turn on. Our results call for changes in how models turn off star formation in early galaxies," the professor stated.

The research team found XMM-2599 formed more than 1,000 solar masses a year in stars at its peak of activity -- an extremely high rate of star formation. In contrast, the Milky Way forms about one new star a year.

"XMM-2599 may be a descendant of a population of highly star-forming dusty galaxies in the very early universe that new infrared telescopes have recently discovered," said Danilo Marchesini, an associate professor of astronomy at Tufts University and a co-author on the study.

"We have caught XMM-2599 in its inactive phase," Wilson said, who led the W. M. Keck Observatory data acquisition
Co-author Michael Cooper, a professor of astronomy at UC Irvine, said this outcome is a strong possibility.

"Perhaps during the following 11.7 billion years of cosmic history, XMM-2599 will become the central member of one of the brightest and most massive clusters of galaxies in the local universe," he said.

"Alternatively, it could continue to exist in isolation. Or we could have a scenario that lies between these two outcomes," he stated.

The study was supported by grants from the National Science Foundation and NASA.

Cape Canaveral, May 31: SpaceX, the private rocket company of billionaire entrepreneur Elon Musk, launched two Americans into orbit from Florida on Saturday in a landmark mission marking the first spaceflight of NASA astronauts from U.S. soil in nine years.

A SpaceX Falcon 9 rocket lifted off from the Kennedy Space Center at 3:22 p.m. EDT (19:22 GMT), launching Doug Hurley and Bob Behnken on a 19-hour ride aboard the company’s newly designed Crew Dragon capsule bound for the International Space Station.

Just before liftoff, Hurley said, “SpaceX, we’re go for launch. Let’s light this candle,” paraphrasing the famous comment uttered on the launch pad in 1961 by Alan Shepard, the first American flown into space.

Minutes after launch, the first-stage booster rocket of the Falcon 9 separated from the upper second-stage rocket and flew itself back to Earth to descend safely onto a landing platform floating in the Atlantic.

High above the Earth, the Crew Dragon jettisoned moments later from the second-stage rocket, sending the capsule on its way to the space station.

The exhilarating spectacle of the rocket soaring flawlessly into the heavens came as a welcome triumph for a nation gripped by racially-charged civil unrest as well as ongoing fear and economic upheaval from the coronavirus pandemic.

The Falcon 9 took off from the same launch pad used by NASA’s final space shuttle flight, piloted by Hurley, in 2011. Since then, NASA astronauts have had to hitch rides into orbit aboard Russia’s Soyuz spacecraft.

“It’s incredible, the power, the technology,” said U.S. President Donald Trump, who was at Kennedy Space Center at Cape Canaveral in Florida for the launch. “That was a beautiful sight to see.”

The mission’s first launch attempt on Wednesday was called off with less than 17 minutes remaining on the countdown clock. Weather again threatened Saturday’s launch, but cleared in time to proceed with the mission.

SPACEFLIGHT MILESTONES

NASA chief Jim Bridenstine has said resuming launches of American astronauts on American-made rockets from U.S. soil is the space agency’s top priority.

“I’m breathing a sigh of relief, but I will also tell you I’m not gonna celebrate until Bob and Doug are home safely.” Bridenstine said.

For Musk, the launch represents another milestone for the reusable rockets his company pioneered to make spaceflight less costly and more frequent. And it marks the first time commercially developed space vehicles - owned and operated by a private entity rather than NASA - have carried Americans into orbit.

The last time NASA launched astronauts into space aboard a brand new vehicle was 40 years ago at the start of the space shuttle program.

Musk, the South African-born high-tech entrepreneur who made his fortune in Silicon Valley, is also chief executive of electric carmaker and battery manufacturer Tesla Inc. He founded Hawthorne, California-based SpaceX, formally known as Space Exploration Technologies, in 2002.

Hurley, 53, and Behnken, 49, NASA employees under contract to fly with SpaceX, are expected to remain at the space station for several weeks, assisting a short-handed crew aboard the orbital laboratory.

Boeing Co, producing its own launch system in competition with SpaceX, is expected to fly its CST-100 Starliner vehicle with astronauts aboard for the first time next year. NASA has awarded nearly $8 billion combined to SpaceX and Boeing for development of their rival rockets.

Trump also hailed the launch as a major advance toward the goal of eventually sending humans to Mars.

He was joined at the viewing by Musk, as well as Vice President Mike Pence, Commerce Secretary Wilbur Ross, Education Secretary Betsy DeVos, Florida congressman Matt Gaetz and Senator Rick Scott.

Earlier on Saturday, the crew bid goodbye to their families. Prior to climbing into a specially designed Tesla automobile for the ride to the launch site, Behnken told his young son, “Be good for mom. Make her life easy.”

During the drive, Behnken and Hurley passed former astronaut Garrett Reisman who held a sign saying, “Take me with you.”

Tokyo, Feb 25: Japan's Chitetsu Watanabe, recognized at 112 years as the oldest man in the world, has passed away 11 days after he received the Guinness World Record certificate, his family said on Tuesday.

Watanabe died on Sunday night, Efe news reported.

He received the official certificate on February 12 at a nursing home in Joetsu in Niigata prefecture, where he resided.

Soon after being certified as the oldest man, he began to experience a lack of appetite and respiratory problems, the wife of his eldest son told public broadcaster NHK.

Born on March 5, 1907 in a family of farmers, Watanabe moved at the age of 20 to Taiwan, where he worked at a sugar refinery for 18 years before returning to Japan after the end of World War II.

A fan of calligraphy, custard and ice cream, Watanabe told the Guinness team that the key to his long life was laughter.

He was recognized as the oldest male in the world following the deaths in 2019 of German Gustav Gerneth (in October), aged 114 years, and Japan's Masazo Nonaka (in January), at the age of 113, three months older than the German.

It remains to be seen who will be recognized after the death of Watanabe, the only male on the list drawn up by the Gerontology Research Group of the 30 oldest people in the world.

Japan has among the highest life expectancy in the world and the number of centenarians in the country has crossed 71,000, according to the latest government figures.

Since 2000, the number of centenarians censored has quintupled, raising concern for the economic outlook and future workforce of the country - where the birthrate is on a downward trend.

Out of these, 88 per cent are women.