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Breathtaking new map of the X-ray Universe – BBC News

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Behold the hot, energetic Universe.

A German-Russian space telescope has just acquired a breakthrough map of the sky that traces the heavens in X-rays.

The image records a lot of the violent action in the cosmos – instances where matter is being accelerated, heated and shredded.

Feasting black holes, exploding stars, and searingly hot gas.

The data comes from the eRosita instrument mounted on Spektr-RG.

This orbiting telescope was launched in July last year and despatched to an observing position some 1.5 million km from Earth. Once commissioned and declared fully operational in December, it was left to slowly rotate and scan the depths of space.

eRosita’s first all-sky data-set, represented in the image at the top of this page, was completed only last week. It records over a million sources of X-rays.

“That’s actually pretty much the same number as had been detected in the whole history of X-ray astronomy going back 60 years. We’ve basically doubled the known sources in just six months,” said Kirpal Nandra, who heads the high-energy astrophysics group at the Max Planck Institute for Extraterrestrial Physics (MPE) in Garching, Germany.

“The data is truly stunning and I think what we’re doing here will revolutionise X-ray astronomy,” he told BBC News.

The map uses the so-called Aitoff projection, which unwraps the sphere of the sky on to an ellipse. The band across the middle is the plane of our Milky Way Galaxy, with the centre of the galaxy in the middle of the ellipse.

The image has been encoded with colour to help describe what’s going on. Blues represent higher energy X-rays (1-2.3 kiloelectron volts, keV); greens are mid-range (0.6-1 keV); and reds are lower energy (0.3-0.6 keV).

Much of the galaxy’s plane is dominated by highly energetic sources. In part, that’s because copious amounts of gas and dust have absorbed and filtered out the lower energy radiation. Sources include stars with strong, magnetically active and extremely hot atmospheres.

The greens and yellows that draw a kind of mushroom feature covering a great swathe of the map represent hot gas inside and just outside our galaxy. This material imprints information about the formation and evolution of the Milky Way.

Some of the bigger splodges are well known actors on the sky. The bright yellow patch just above the plane on the far right is a concentration of supernova remnants – the wreckage of stars that have exploded and whose shockwaves have super-heated a surrounding cocoon of dust and gas. This particular patch is dominated by the Vela supernova remnant. This was an explosion that happened thousands of years ago but a mere 800 light-years from Earth.

Look next at the diffuse red glow at the top and bottom of the map. This is largely X-ray emission from hot gas well beyond our galaxy. And in the white speckles, we are seeing principally the signature of super-massive black holes. Indeed, about 80% of all the sources contained in the new map are the gargantuan black holes that reside at the centres of distant galaxies. They pump out X-rays as their immense gravitational pull draws in and eviscerates matter.

Some of super-massive black holes making an appearance in the map are seen when the Universe was younger than one billion years old, less than 10% of its present age.

Spektr-RG and its eRosita instrument intend to gather seven more all-sky surveys over the next 3.5 years. This will enable the telescope to refine its data, to remove artefacts and noise, but also to sense deeper into the cosmos and pick up the faint sources that would otherwise be beyond detection.

One key goal is to map the distribution of the hot, X-ray-emitting gas that illuminates the great clusters of galaxies.

Astronomers hope this information can lead them to some fresh insights on how the Universe is structured and how it has changed through time. It’s possible there may be some clues in this project about the nature of dark energy, the mysterious “force” that appears to be pushing the cosmos apart at an ever accelerating rate.

“That’s the big prize, but it would only come at the end of the mission,” explained Prof Nandra.

“Eight surveys allows us to go really deep into the distant Universe. Basically, we’re trying to detect all of the clusters of galaxies in the Universe above a certain mass limit. We’ve got a nice sample already – maybe around 10,000. But we’re hoping to get at least 100,000 clusters of galaxies.”

eRosita is the German element on Spektr-RG. It takes up most of the room on the spacecraft bus, or chassis. But it sits next to a Russian instrument known as ART-XC, which is sensitive to higher energies, up to 30 keV.

Both eRosita and ART-XC use a cluster of seven tubular mirror modules to corral X-ray light down on to their sensitive camera detectors.

Jonathan.Amos-INTERNET@bbc.co.uk and follow me on Twitter: @BBCAmos

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Rocket Lab Electron launch fails – SpaceNews

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Updated 6:15 p.m. Eastern.

WASHINGTON — A Rocket Lab Electron rocket failed to reach orbit during a July 4 launch after a problem during the rocket’s second-stage burn.

The Electron rocket lifted off from the company’s Launch Complex 1 at Mahia Peninsula, New Zealand, at 5:19 p.m. Eastern. The launch was originally scheduled for July 3 but pushed back two days because of poor weather in the forecast, only for the company to move up the launch to July 4 based on a reassessment of the weather.

The initial phases of the launch appeared to go as planned, although the vehicle’s passage through “max-q,” or maximum dynamic pressure, appeared to be rougher than what was seen in previous launches. Onboard video taken shortly before first-stage separation showed material appearing to peel from the rocket, although it was not clear if it simply a decal applied to the rocket or something more substantial.

The onboard video from the rocket froze about five minutes and 45 seconds after liftoff, or three minutes into the seconds stage burn. At six and a half minutes after liftoff, a launch controller on the company’s webcast of the launch said, “Initiating mishap response plan.”

Telemetry from the rocket, displayed on the webcast, showed the rocket’s altitude falling from about 194 kilometers to less than 165 kilometers for about 90 seconds before that information was removed from the screen. The company ended the webcast 11 minutes after liftoff, two minutes after the rocket’s second stage should have shut down and the kick stage, carrying its payload of seven satellites, deployed.

“An issue was experienced today during Rocket Lab’s launch that caused the loss of the vehicle. We are deeply sorry to the customers on board Electron,” the company tweeted about 25 minutes after liftoff. “The issue occurred late in the flight during the 2nd stage burn. More information will be provided as it becomes available.”

“We lost the flight late into the mission. I am incredibly sorry that we failed to deliver our customers satellites today,” Peter Beck, chief executive of Rocket Lab, tweeted after the failure. “Rest assured we will find the issue, correct it and be back on the pad soon.”

The launch was the 13th for the Electron rocket. The vehicle had 11 consecutive successful launches after the rocket’s inaugural launch in May 2017 was terminated because of a telemetry issue involving range safety systems, and not a problem with the rocket itself.

The primary payload for the launch was CE-SAT-1B, a 67-kilogram imaging satellite built by Canon Electronics, whose launch was arranged by Spaceflight Inc. The satellite, capable of taking images with a resolution of 90 centimeters, was intended to demonstrate the spacecraft’s technologies as the company prepared mass production of similar satellites.

“This launch is very critical for Canon Electronics as we are launching a satellite where we have remarkably increased the ratio of in-house development of components compared to the previous launch,” said Nobutada Sako, group executive of the Satellite Systems Lab at Canon Electronics said in a pre-launch release. Canon launched a similar satellite, CE-SAT-1, in 2017.

The rocket carried five SuperDove imaging cubesats developed by Planet. These satellites are upgraded versions of its original Dove line of cubesats, with additional spectral bands to support geospatial applications in fields like architecture.

The seventh satellite on the Electron was Faraday-1, a six-unit cubesat developed by British startup In-Space Missions. The satellite is the first in a series by the company designed to carry hosted payloads. Faraday-1 included payloads for several customers such Airbus Defence and Space, which flew a payload called Prometheus 1 to test a reprogrammable software-defined radio.

This mission, dubbed “Pics or It Didn’t Happen” by Rocket Lab, featured the shortest turnaround time between Electron missions to date. The previous Electron launch, which carried three National Reconnaissance Office satellites and smallsats for American and Australian universities, launched June 13.

After a halt in launch activity caused by the coronavirus pandemic, Rocket Lab had planned to ramp up its launch activity in the second half of the year. The next mission after this was to take place with an even shorter turnaround, Beck said in a June 18 interview. The company was also looking ahead to a first Electron launch from Launch Complex 2 in Virginia that, prior to this failure, was expected to take place before the end of the summer.

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'Canada, Canada, Cana…da': Researchers Spot Change To White-Throated Sparrow's Song – NPR

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MARY LOUISE KELLY, HOST:

Experienced birders might be familiar with the sounds of the white-throated sparrow. Some say the end of the call sounds like the word Canada repeated several times.

(SOUNDBITE OF WHITE-THROATED SPARROW CALLING)

KEN OTTER: Canada, Canada, Canada, Canada.

KELLY: That is Dr. Ken Otter. In 2000 he was doing his first field study in northern British Columbia. He was studying area bird populations and made a discovery.

OTTER: I was working on chickadees, but I noticed that there was white-throated sparrows around.

KELLY: White-throated sparrows – they weren’t known to be in the area, but there they were. And they sounded a bit different.

OTTER: They were going, can-a-can-a-can-a-Canada-da (ph), almost like they were stuttering that last phrase.

(SOUNDBITE OF WHITE-THROATED SPARROW CALLING)

KELLY: Otter figured this unusual new tune was maybe specific to this one community of sparrows.

OTTER: It wasn’t until seven or eight years later that we started to realize that the song was actually spreading eastwards.

KELLY: Yeah. In 2004 only around half of the sparrows in Alberta, Canada, were singing the song. By 2014, that had changed. You might say the tweet went viral.

OTTER: All the birds in Alberta were now singing this Western dialect.

KELLY: Now, Otter does not know why exactly this new song has caught on. He imagines this little spark of variation maybe might improve a male sparrow’s chances with the ladies.

OTTER: If there’s a little bit of female preference, which is something we want to test next, then it would be advantageous for males to sing an atypical song. And after a while, it would just take over.

KELLY: In that case, it seems like the white-throated sparrow’s sultry new crooner is here to stay.

(SOUNDBITE OF THE BEATLES’ “FLYING”)

KELLY: You’re listening to All Tweets Considered.

Copyright © 2020 NPR. All rights reserved. Visit our website terms of use and permissions pages at www.npr.org for further information.

NPR transcripts are created on a rush deadline by Verb8tm, Inc., an NPR contractor, and produced using a proprietary transcription process developed with NPR. This text may not be in its final form and may be updated or revised in the future. Accuracy and availability may vary. The authoritative record of NPR’s programming is the audio record.

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How can we be alone? – Skywatching – Castanet.net

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The latest estimate is that there are around six billion Earth-like planets in our galaxy alone.

However, when we really dig into the issue regarding what makes a planet suitable for life as we know it, this large number could be a considerable understatement.

First, we know about places where liquid water and warmth are available for living things, but otherwise they are very un-Earth-like — such as Europa, one of the moons of Jupiter, where tidal forces warm an ocean hidden under a roof of ice.

For the moment, let’s just stick to the Earth-like planets. The starting point in identifying an Earth-like planet is that it is the right size, it has an atmosphere, and its surface temperature is high enough to support a water ocean.

There also needs to be a water cycle, where water evaporates from the ocean and returns to it as rain. If there are landmasses, they will be irrigated and material will be eroded from the land and taken into the sea as nutrients for living creatures. However, there is a range of conditions under which this may happen.

First, the planet should be in the Goldilocks Zone, where the planet receives enough warmth and light from its star to ensure a high enough surface temperature and to drive a water cycle.

This is where the situation becomes more complicated. Planets, including ours, exist in a thermal equilibrium. Heat from our star warms our world. As the temperature rises, the Earth radiates increasing amounts of infrared, sending heat off into space.

Eventually, the input and output are equal and the planet’s temperature stabilizes. Intriguingly though, if we do this calculation for the Earth, we find our planet should be frozen solid, with a mean temperature more or less equal to the Moon’s, around minus 50C.

This obviously isn’t the case, and the explanation is the greenhouse effect. Gases such as water vapour, carbon dioxide and methane are greenhouse gases, which means they impeded the ability of a planet to re-radiate heat into space.

The result is that in order to meet a balance of input and output, the planet has to be hotter. Planets with lots of greenhouse gases can be further from their stars and still have comfortable temperatures.

Planets with atmospheres low in greenhouse gases must be closer. The atmospheres of young planets are rich in greenhouse gases.

During the 4.5 billion years since the Earth formed, the Sun has brightened steadily, but on Earth living things removed them and replaced them with oxygen, which is not a greenhouse gas, keeping our environment stable and our planet inhabitable.

In the 1970s, James Lovelock proposed the Gaia Hypothesis (Gaia is the Earth goddess), in which he proposed that once life is established, it has a certain power to keep its environment comfortable.

There are two other factors.

First, there are clouds.

Water evaporated from the oceans by solar heat forms clouds, which can reflect solar energy back into space, providing a stabilizing influence. Of course, more energy in the atmosphere can drive more severe weather.

Second, there is dust.

Every day, warm air heated by contact with warm ground rises, carrying dust with it.  This can act as an insulator, keeping in heat, or as a reflector, sending it back out, depending on the grain size and the amount.

In addition to being the right distance from their stars, we need our planets to have an atmosphere and a signature of water vapour.

If we see oxygen, which needs living things to produce and maintain it, we can be pretty sure there are living things.

Maybe fortunately, the distances between stars ensure it will be a long time before we can interfere with our alien brethren or they with us.

  • Jupiter and Saturn rise in the southeast around midnight
  • Mars follows in the early hours.
  • Venus lies low in the sunrise glow.
  • The Moon will reach Last Quarter on the 12th.

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