New Universe map unearths 300,000 more galaxies

A new project found 300,000 previously unseen light sources using a telescope that can detect light sources optical instruments cannot see. Above, galaxy MACS1149-JD1 located 13.28 billion light-years away as seen with the NASA/ESA Hubble Space Telescope in May 2018. (AFP)
Updated 19 February 2019
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New Universe map unearths 300,000 more galaxies

  • Discovery literally sheds new light on some of the Universe’s deepest secrets
  • More than 200 astronomers from 18 countries were involved in the study

PARIS: The known Universe just got a lot bigger.
A new map of the night sky published Tuesday charts hundreds of thousands of previously unknown galaxies discovered using a telescope that can detect light sources optical instruments cannot see.
The international team behind the unprecedented space survey said their discovery literally shed new light on some of the Universe’s deepest secrets, including the physics of black holes and how clusters of galaxies evolve.
“This is a new window on the universe,” Cyril Tasse, an astronomer at the Paris Observatory who was involved in the project, said.
“When we saw the first images we were like: ‘What is this?!’ It didn’t look anything at all like what we are used to seeing.”
More than 200 astronomers from 18 countries were involved in the study, which used radio astronomy to look at a segment of sky over the northern hemisphere, and found 300,000 previously unseen light sources thought to be distant galaxies.
Radio astronomy allows scientists to detect radiation produced when massive celestial objects interact.
The team used the Low Frequency Array (LOFAR) telescope in the Netherlands to pick up traces — or “jets” — of ancient radiation produced when galaxies merge. These jets, previously undetected, can extend over millions of light years.
“With radio observations we can detect radiation from the tenuous medium that exists between galaxies,” said Amanda Wilber, of the University of Hamburg.
“LOFAR allows us to detect many more of these sources and understand what is powering them.”
The discovery of the new light sources may also help scientists better understand the behavior of one of space’s most enigmatic phenomena.
Black holes — which have a gravitational pull so strong that no matter can escape them — emit radiation when they engulf other high-mass objects such as stars and gas clouds.
Tasse said the new observation technique would allow astronomers to compare black holes over time to see how they form and develop.
“If you look at an active black hole, the jets (of radiation) disappear after millions of years, and you won’t see them at a higher frequency (of light),” he said.
“But at a lower frequency they continue to emit these jets for hundreds of millions of years, so we can see far older electrons.”
The Hubble telescope has produced images that lead scientists to believe there are more than 100 billion galaxies in the Universe, although many are too old and distant to be observed using traditional detection techniques.
The map created by the LOFAR observations, part of which was published in the journal Astronomy & Astrophysics, contains data equivalent to ten million DVDs yet charts just two percent of the sky.
The LOFAR telescope is made up of a Europe-wide network of radio antenna across seven countries, forming the equivalent of a 1,300-kilometer diameter satellite dish.
The team plans to create high-resolution images of the entire northern sky, which they say will reveal as many as 15 million as-yet undetected radio sources.
“The oldest objects in the Universe are around 11-12 billion light years old,” said Tasse. “So we are going to see lots more of these objects.”


SpaceX launches first satellites for Musk’s Starlink Internet service

Updated 24 May 2019
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SpaceX launches first satellites for Musk’s Starlink Internet service

  • The rocket blasted off from Cape Canaveral Air Force Station at about 10:30 p.m. local time
  • The Falcon 9 was due to release its cargo of 60 satellites into orbit about an hour after Thursday’s launch

CAPE CANAVERAL, Florida: High-tech entrepreneur Elon Musk’s SpaceX company launched a Falcon 9 rocket from Florida on Thursday on a mission to carry the first batch of five dozen small satellites into low-Earth orbit for his new Starlink Internet service.
The rocket blasted off from Cape Canaveral Air Force Station at about 10:30 p.m. local time (0230 GMT Friday), marking a milestone in a global enterprise aimed at generating cash for Musk’s larger ambitions in space.
The launch came a week after two back-to-back countdowns for the mission were scrubbed — once due to high winds over the Cape and the next night in order to update satellite software and “triple-check” all systems.
The Falcon 9 was due to release its cargo of 60 satellites into orbit about an hour after Thursday’s launch. Each one weighs 500 pounds (227 kg), making it the heaviest payload for any SpaceX rocket to date.
Those satellites are designed to form the initial phase a planned constellation capable of beaming signals for high-speed Internet service from space to paying customers around the globe.
Musk has said he sees the new Starlink venture as an important new revenue stream for his California-based Space Exploration Technologies, known as SpaceX, whose launch service income he expects to top out at around $3 billion a year.
Speaking to reporters last week, Musk said that makes Starlink pivotal in helping pay for his larger goals of developing a new spacecraft to fly paying customers to the moon and for eventually trying to colonize Mars.
“We think this is a key stepping stone on the way toward establishing a self-sustaining city on Mars and a base on the moon,” said Musk, the billionaire entrepreneur who is also chief executive officer of automaker Tesla Inc.
At least 12 launches carrying similar payloads are needed to achieve constant Internet coverage of most of the world, Musk said. Starlink is only currently authorized for operations in the United States.
Musk faces stiff competition. In February, Airbus SE-backed OneWeb launched its own clutch of satellites, while LeoSat Enterprises and Canada’s Telesat are also working to build data networks.
In each network, the tiny satellites orbit closer to Earth than traditional communications satellites, a technological shift made possible by advances in laser technology and computer chips.
Musk said SpaceX would begin approaching customers later this year or next year. As many as 2,000 satellites will be launched per year, with the ultimate objective of placing up to 12,000 into orbit.