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Astronomers Find The Oldest, Most Distant Galaxy to Date

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Since time immemorial, philosophers and scholars have contemplated the beginning of time and even tried to determine when all things began. It’s only been in the age of modern astronomy that we’ve come close to answering that question with a fair degree of certainty.

According to the most widely-accepted cosmological models, the Universe began with the Bang Bang roughly 13.8 billion years ago.

Even so, astronomers are still uncertain about what the early Universe looked like since this period coincided with the cosmic “Dark Ages”. Therefore, astronomers keep pushing the limits of their instruments to see when the earliest galaxies formed.

Thanks to new research by an international team of astronomers, the oldest and most distant galaxy observed in our Universe to date (GN-z11) has been identified.

The team, whose research was recently published in the journal Nature Astronomy, was led by Linhua Jiang of the Kavli Institute for Astronomy and Astrophysics and Prof. Nobunari Kashikawa of the University of Tokyo.

They were joined by researchers from the Observatories of the Carnegie Institution for Science, the Steward Observatory, the Geneva Observatory, Peking University, and the University of Tokyo.

Simply put, the cosmic Dark Ages began about 370 thousand years after the Big Bang and continued for another 1 billion years.

At this time, the only light sources were either the photons released before – which is still detectable today as the Cosmic Microwave Background (CMB) – and those released by neutral hydrogen atoms. The light of these photons is so shifted due to the expansion of the Universe that they are invisible to us today.

This effect is known as “redshift,” where the wavelength of light is elongated (or “shift” towards the red end of the spectrum) as it passes through the ever-expanding cosmos on its way to reach us.

For objects moving closer to our galaxy, the effect is reversed, with the wavelength shortening and shifting towards the blue end of the spectrum (aka. “blueshift”).

For nearly a century, astronomers have used these effects to determine the distance of galaxies and the rate at which the Universe is expanding. In this case, the research team used the Keck I telescope at Maunakea, Hawaii, to measure the redshift of GN-z11 to determine its distance.

The results they obtained indicated that it is the farthest (and oldest) galaxy ever observed. As Kashikawa explained in a University of Tokyo press release:

“From previous studies, the galaxy GN-z11 seems to be the farthest detectable galaxy from us, at 13.4 billion light years, or 134 nonillion kilometers (that’s 134 followed by 30 zeros). But measuring and verifying such a distance is not an easy task.”

Specifically, the team examined the carbon emissions lines coming from GN-z11, which were in the ultraviolet range when they left the galaxy and were shifted by a factor of 10 – to the infrared (0.2 micrometers) – by the time it reached Earth.

This level of redshift indicates that this galaxy existed as observed roughly 13.4 billion years ago – aka just 400 million years after the Big Bang.

At this distance, GN-z11 is so far that it defines the very boundary of the observable Universe itself! While this galaxy had been observed in the past (by Hubble), it took the resolving power and spectroscopic capabilities of the Keck Observatory to make accurate measurements.

This was performed as part of the Multi-Object Spectrograph for Infrared Exploration (MOSFIRE) survey, which captured the emission lines from GN-z11 in detail.

This allowed the team to produce distance estimates for this galaxy that were improved by a factor of 100 over any measurements that were previously made. Said Kashikawa:

“The Hubble Space Telescope detected the signature multiple times in the spectrum of GN-z11. However, even the Hubble cannot resolve ultraviolet emission lines to the degree we needed. So we turned to a more up-to-date ground-based spectrograph, an instrument to measure emission lines, called MOSFIRE, which is mounted to the Keck I telescope in Hawaii.”

If subsequent observations can confirm the results of this latest study, then the astronomers can say with certainty that GN-z11 is the farthest galaxy ever observed. Through the study of objects like this one, astronomers hope to be able to shed light on a period of cosmic history when the Universe was just a few hundred millions of years old.

This period coincides with the Universe was beginning to emerge from the “Dark Ages”, when the first stars and galaxies formed and filled the early Universe with visible light.

By studying these, astronomers hope to learn more about how the large-scale structures of the Universe subsequently evolved. This will be assisted by next-generation telescopes like the James Webb Space Telescope (JWST) – scheduled to launch on 31 October, 2021.

These instruments will even allow astronomers to be able to study the the “Dark Ages” itself, a time when the only non-CMB light was the spin line of neutral hydrogen – in the far microwave wavelength (21 cm).

To be able to probe the very beginnings of the Universe itself and watch as the first stars and galaxies form. What a time an exciting that will be!

The observations that made this research possible were conducted under the time exchange program between the Keck Observatory and the Subaru Telescope on Maunakea, Hawaii.

Source: – ScienceAlert

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SpaceX to launch dozens of satellites on Transporter-1 flight Sunday and you can watch it live – Space.com

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[embedded content]

Update for Jan. 23, 9:35 a.m. ET: Poor weather conditions forced SpaceX to scrub the launch this morning. The company is now targeting launch at 10 a.m. EST (1500 GMT) liftoff on Sunday, Jan. 24. You can read our new story here

Original story:

CAPE CANAVERAL, Fla. — SpaceX is preparing one of its veteran rockets to launch 143 satellites into space on Saturday (Jan. 23). You can watch the fiery action live online. 

A two-stage Falcon 9 rocket flight is scheduled to take off from Space Launch Complex 40 at Cape Canaveral Space Force Station here in Florida. Liftoff is expected during a one-hour window that opens at 9:40 a.m. EST (1440 GMT). 

Perched atop the 230-foot-tall (70 meters) launcher will be dozens of satellites as part of a dedicated rideshare mission. This cosmic carpool, known as Transporter-1, will also be ferrying 10 of the company’s own Starlink satellites into space and depositing them in a polar orbit — a first for the growing network of broadband satellites. Other payloads include 48 Earth-observing SuperDove satellites for Planet and one small nanosatellite called “Charlie” for Aurora Insight.

You’ll be able to watch the launch action live here and on the Space.com homepage, courtesy of SpaceX, or you can watch directly from SpaceX here about 15 minutes before liftoff.

Related: See the evolution of SpaceX’s rockets in pictures

Saturday’s launch marks the third mission of 2021 for SpaceX and the second in just two days from Florida’s Space Coast. The California-based rocket manufacturer launched a different Falcon 9 on a record-breaking flight on Wednesday (Jan. 20) to deliver a full stack of 60 Starlink satellites into orbit. 

The booster used on that mission became the first in SpaceX’s fleet of frequent fliers to launch and land eight times. (The previous record was seven, which was held by two different first-stage boosters.) 

Following liftoff on Saturday, the Transporter-1 Falcon 9 rocket’s first stage is expected to land on SpaceX’s drone ship “Of Course I Still Love You,” which is waiting out in the Atlantic. If successful, it will mark the 73rd recovery of a first-stage booster for SpaceX.  

It will also mark the first catch of the year for the veteran drone ship, which has sat out the past two missions while being refurbished.

SpaceX’s very big year: A 2020 of astronaut launches, Starship tests & more

The Falcon 9 rocket for the Transporter-1 launch  is a four-time flier and a record-setter as well. Known as B1058, this flight proven booster will embark on its fifth flight and, if all goes according to plan, will be able to stick its landing at sea.

B1058 made history in May when it launched two NASA astronauts — Doug Hurley and Bob Behnken — to the International Space Station on the first crewed flight to launch from U.S. soil since the retirement of the space shuttle program in 2011. 

Emblazoned with NASA’s iconic worm logo, the booster also ferried a communications satellite for South Korea’s military, a batch of Starlink satellites and  a Dragon cargo capsule to the ISS for SpaceX’s 21st cargo resupply mission.  

For its next mission, the veteran will serve as a kind of space Uber, delivering a group of small satellites into orbit as part of SpaceX’s rideshare program, which aims to help smaller satellites get into space by sharing a ride much like an Uber pool. 

SpaceX announced the program in August 2020, offering rides on a Falcon for $1 million a pop. The launch slots are booked through the company’s website and are offered on regular intervals approximately four times per year. 

Rideshares missions are not exactly new for SpaceX as the company launched more than 60 satellites from its California launch pad in December 2018. That mission, dubbed SSO-A, delivered a small armada of satellites into low-Earth orbit through a carefully choreographed orbital ballet so that the satellites did not collide with one another. 

Since then, SpaceX has ferried other payloads to space on a few of its Starlink missions. Those missions included small cubesat satellites for Planet and BlackSky

SpaceX’s two net-equipped boats — called GO Ms. Tree and GO Ms. Chief — will be part of the recovery team deployed for this mission. They will attempt to recover the two pieces of the rocket’s nose cone, known as the payload fairing, after they fall back to Earth.

The dynamic duo supported the Starlink mission earlier this week and are currently en route to the Transporter-1 mission’s designated landing zone. (Each fairing half is equipped with parachutes and on board navigation software that steers it to a specific landing zone out in the Atlantic Ocean.)

For the Starlink mission, the boats scooped the pieces out of the water and will likely do the same thing for this mission. That determination will be made officially on launch day. 

Currently, weather forecasts predict an 60% chance of good conditions for the launch opportunity on Saturday, with the only weather concerns being the potential for thick clouds over the launch site. 

Follow Amy Thompson on Twitter @astrogingersnap. Follow us on Twitter @Spacedotcom or Facebook. 

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Hot enough for you? 2020, 2016 tie for warmest years on record – NewmarketToday.ca

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It’s official: 2020 was tied with 2016 as the warmest year on record, the European Union’s Copernicus Climate Change Service (C3S) is reporting.

Last year, 2020, matches the 2016 record despite the cooling effects of a La Niña event whereas 2016 began with a strong warming El Niño.

The six years beginning in 2015 are the hottest six years and 2011 to 2020 was the warmest decade recorded. 2020 was 0.6°C warmer than the baseline 1981-2010 reference period and 1.25°C above pre-industrial temperatures.

Some of the largest annual temperature rises occurred in the Arctic and northern Siberia regions, with temperatures reaching over 6°C higher than the baseline in some areas.

There was an unusually active wildfire season in Northern Ontario, with that released a record 244 megatonnes of carbon dioxide in 2020, more than a third higher than the 2019 record. Arctic sea ice was significantly lower than average during the second half of the year with the lowest extent of sea ice on record for the months of July and October. 

“2020 stands out for its exceptional warmth in the Arctic and a number of tropical storms in the North Atlantic,” commented Carlo Buontemp, director of C3S. “It is no surprise that the last decade was the warmest on record, and is yet another reminder of the urgency of ambitious emissions reductions to prevent adverse climate impacts in the future.”

Concentrations of atmospheric carbon dioxide continued to rise despite the approximately seven percent reduction of fossil fuel carbon dioxide emissions due to COVID-19 pandemic lockdowns around the world.

An initial pandemic-related 17 per cent reduction in emissions was followed by record high carbon dioxide levels in May. While the overall rise was slightly less than in 2019, scientists warn this should not be cause for complacency.  Until net global emissions are reduced to zero, carbon dioxide will continue to accumulate and drive further climate change, said Vincent-Henri Peach, director of the Copernicus Atmosphere Monitoring Service.

Countries that signed onto the 2015 Paris climate agreement committed to limiting warming by no more than 1.5°C with a goal of less than 2°C. Scientists say this will require countries to commit to a more rapid transition away from fossil fuel dependency by investing in renewable energy. 

“The extraordinary climate events of 2020 and the data from the C3S show us that we have no time to lose,” said Matthias Petschke of the European Commission’s Directorate-General for Defence Industry and Space. “We must come together as a global community, to ensure a just transition to a net zero future. It will be difficult, but the cost of inaction is too great.”

– Lori Thompson, Local Journalism Initiative, Manitoulin Expositor

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Starlink satellite internet grants instant sign-up for eligible Canadians – Canada.com

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Article content continued

In a CBC article, some Starlink subscribers have reported service speeds of up to 150Mbps.

The Canadian Radio-Television and Telecommunication Commission (CRTC) granted Starlink’s operator, SpaceX, a Basic International Telecommunications Service (BITS) license in October 2020. The license allows SpaceX to provide telecommunication services in Canada but does not allow it to operate as an internet service provider within the issuing nation.

Related:

SpaceX granted basic telecom license in Canada  

Starlink says it aims to establish a global network by using a massive constellation of satellites. The satellites float at low earth orbit, which both cuts down on signal latency and can more easily return to earth once they’re decommissioned. But stargazers are worried that the massive amount of satellites could obscure the view of the night sky.

The company has expressed a keen interest in providing internet service to rural and underserved areas in Canada and the United States. It’s currently extending beta testing offers in Canada, U.S. and U.K.

Starlink says it has launched 955 satellites so far.

The post Starlink satellite internet grants instant sign-up for eligible Canadians first appeared on IT World Canada.

This section is powered by IT World Canada. ITWC covers the enterprise IT spectrum, providing news and information for IT professionals aiming to succeed in the Canadian market.

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