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From Venus meeting Mars to Thunder moon: Celestial events in July to keep an eye out for – Firstpost

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This month stargazers are in for a treat since there is a long list of exciting events lined up for you. It will include meteors’ showers, Venus being spotted after sunset and planetary conjunctions, July will be an astronomer’s delight.

Night sky.

Take a look at the dates and time for all these astronomical events:

  • Thursday, 8 July: For a very short time period before sunrise, the moon will be positioned several finger-widths to the left of the bright dot of Mercury. The moon and Mercury will be close enough to see through binoculars, but stargazers must remember to turn their optics away before the sun rises.
  • Friday, 9 July: On this day, the moon will officially reach its new phase. It is the right day for star watchers to look at the moon as it becomes unobservable from anywhere on Earth for about a day.
  • Sunday, 11 July: On this day, the crescent moon will shine 6.5 degrees to the celestial northwest of the two planets – Venus and Mars. Before they set at about 10:00 pm, stargazers can catch the trio when they are composed of some interesting scenery.
  • Monday, 12 July: During the evenings, Venus and Mars will meet in very close conjunction. While both planets will be travelling eastward in their orbits, it will look like Venus kissing Mars as it will catch up and pass each other.
  • Friday, 16 July: For a few hours in the sky, Lunar X will become visible for stargazers. As per space.com, the Lunar X is located on the terminator where it is predicted to develop and then gradually fade out in due course of time.
  • Saturday, 17 July: On this day, the moon will complete the first quarter of its orbit around Earth. Usually, in the first quarter, the moon rises around mid-day and sets around midnight, so it will be visible in the afternoon daytime sky. On the same day, Pluto will reach opposition for 2021. During this time, the earth will be positioned between Pluto and the sun. It will minimize our distance from that outer world.
  • Sunday, 18 July: An asteroid named Pallas will halt its regular eastward motion and begin a retrograde loop that will last until early November. For stargazers, the asteroid and stars will appear together in the telescope.
  • Tuesday, 20 July: This is a special day as it will be the 52nd anniversary of man’s first steps on another world. On this day, six crewed Apollo Missions were sent to different regions of the moon to carry out experiments.
  • Wednesday, 21 July: On this day, the bright planet Venus will gleam above the prominent double star Regulus in Leo. Both will be observable in binoculars for the entire week.
  • Friday, 23 July: The moon will reach its full phase which is commonly called the Buck Moon, Thunder Moon, or Hay Moon. It always shines in or near the stars of Sagittarius or Capricorn.
  • Saturday, 24 July: Skywatchers will be able to see a natural satellite shining very brightly below and between bright Jupiter on the left and Saturn on the right. The trio will make a nice wide-field photo opportunity for people interested.
  • Sunday, 25 July: On this day, the moon’s eastward orbital motion will move towards Jupiter. The pair will be visible in binoculars all night long.
  • Thursday, 29 July: This special day will feature the annual Southern Delta Aquariids meteor shower that will last from 21 July to 23 August.
    On the same day, Mars will follow in Venus’ footsteps. They will be visible after sunset, with Venus shining brightly. Also, observers in Central Europe, the Middle East and most of Asia will be able to see small round black shadows crossing Jupiter at the same time on 29 July.
  • Saturday, 31 July: For the second time in July, the moon will reach its third quarter phase. This week of moonless nights will be the best time for observing deep-sky targets.

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Hot and dry: SPIRou reveals the atmosphere of hot Jupiter Tau Boötis b – News | Institute for Research on Exoplanets

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Measuring the composition of the atmosphere of the hot Jupiter Tau Boötis b more precisely than ever, an iREx-led team of astronomers provides a better understanding of giant exoplanets.

Artistic rendition of the exoplanet Tau Boötis b and its host star, Tau Boötis. Credit : ESO/L. Calçada.

Using the SPIRou spectropolarimeter on the Canada-France-Hawaii Telescope in Hawaii, a team led by Stefan Pelletier, a PhD student at Université de Montréal’s Institute for Research on Exoplanets (iREx), studied the atmosphere of the gas giant exoplanet Tau Boötis b, a scorching hot world that takes a mere three days to orbit its host star. 

Their detailed analysis, presented in a paper published today in the Astronomical Journal, shows that the atmosphere of the gaseous planet contains carbon monoxide, as expected, but surprisingly no water, a molecule that was thought to be prevalent and should have been easily detectable with SPIRou. 

Tau Boötis b is a planet that is 6.24 times more massive than Jupiter and eight times closer to its parent star than Mercury is to the Sun. Located only 51 light-years from Earth and 40 per cent more massive than the Sun, its star, Tau Boötis, is one of the brightest known planet-bearing stars, and is visible to the naked eye in the Boötes constellation.

Tau Boötis b was one of the first exoplanets ever discovered, in 1996, thanks to the radial velocity method, which detects the slight back-and-forth motion of a star generated by the gravitational tug of its planet. Its atmosphere had been studied a handful of times before, but never with an instrument as powerful as SPIRou to reveal  its molecular content. 

Searching for water 

Assuming Tau Boötis b formed in a protoplanetary disk with a composition similar to that of our Solar System, models show that water vapour should be present in large quantities in its atmosphere. It should thus have been easy to detect with an instrument such as SPIRou.

“We expected a strong detection of water, with maybe a little carbon monoxide,” explained Pelletier. “We were, however, surprised to find the opposite: carbon monoxide, but no water.”

The team worked hard to make sure the results could not be attributed to problems with the instrument or the analysis of the data.

“Once we convinced ourselves the content of water was indeed much lower than expected on Tau Boötis b, we were able to start searching for formation mechanisms that could explain this,” said Pelletier.

Studying hot Jupiters to better understand Jupiter and Saturn

“Hot Jupiters like Tau Boötis b offer an unprecedented opportunity to probe giant planet formation”, said co-author Björn Benneke, an astrophysics professor and  Pelletier’s PhD supervisor at UdeM. “The composition of the planet gives clues as to where and how this giant planet formed.”

The key to revealing the formation location and mechanism of giant planets is imprinted in their molecular atmospheric composition. The extreme temperature of hot Jupiters allows most molecules in their atmospheres to be in gaseous form, and therefore detectable with current instruments. Astronomers can thus precisely measure the content of their atmospheres.

“In our Solar System, Jupiter and Saturn are really cold,” said Benneke. “Some molecules such as water are frozen and hidden deep in their atmospheres; thus, we have a very poor knowledge of their abundance. Studying hot Jupiters provides a way to better understand our own giant planets. The low amount of water on Tau Boötis b could mean that our own Jupiter is also drier than we had previously thought.” 



SPIRou: a unique instrument

Tau Boötis b is one of the first planets studied with the new SPIRou instrument since it was recently put into service at the Canada-France-Hawaii Telescope. This instrument was developed by researchers from several scientific institutions including UdeM.

“This spectropolarimeter can analyze the planet’s thermal light — the light emitted by the planet itself — in an unprecedentedly large range of colours, and with a resolution that allows for the identification of many molecules at once: water, carbon monoxide, methane, etc.” said co-author and iREx researcher Neil Cook, an expert on the SPIRou instrument. 

The team spent 20 hours observing the exoplanet with SPIRou between April 2019 and June 2020.

“We measured the abundance of all major molecules that contain either carbon or oxygen,” said Pelletier. “Since they are the two most abundant elements in the universe, after hydrogen and helium, that gives us a very complete picture of the content of the atmosphere.” 

Like most planets, Tau Boötis b does not pass in front of its star as it orbits around it, from Earth’s point of view. However, the study of exoplanet atmospheres has mostly been limited to “transiting” planets – those that cause periodic dips in the light of their star when they obscure part of their light.

“It is the first time that we get such precise measurements on the atmospheric composition of a non-transiting exoplanet,” said PhD student Caroline Piaulet, a co-author of the study.

“This work opens the door to studying in detail the atmospheres of a large number of exoplanets, even those that do not transit their star.” 

A composition similar to Jupiter

Through their analysis, Pelletier and his colleagues were able to conclude that Tau Boötis b’s atmospheric composition has roughly five times as much carbon as that found in the Sun, quantities similar to that measured for Jupiter. 

This may be a suggest that hot Jupiters could form much further from their host star, at distances that are similar to the giant planets in our Solar System, and have simply experienced a different evolution, which included a migration towards the star. 

“According to what we found for Tau Boötis b, it would seem that, at least composition-wise, hot Jupiters may not be so different from our own Solar System giant planets after all,” concluded Pelletier.

About this study 

Where is the water? Jupiter-like C/H ratio but strong H2O depletion found on Tau Boötis b using SPIRou,” by Stefan Pelletier et al., was published July 28th, 2021 in the Astronomical Journal. 

In addition to Stefan Pelletier, Björn Benneke, Neil Cook and Caroline Piaulet, the team includes Institute for research on exoplanets (iREx) members Antoine Darveau-Bernier, Anne Boucher, Louis-Philippe Coulombe, Étienne Artigau, David Lafrenière, Simon Delisle, Romain Allart, René Doyon, Charles Cadieux and Thomas Vandal, all based at Université de Montréal, and seven other co-authors from France, the United States, Portugal and Brazil. 

Funding was provided by the the Technologies for Exo-Planetary Science (TEPS) CREATE program, the Fonds de recherche du Québec – Nature et technologies (FRQNT), the Natural Sciences and Engineering Research Council of Canada (NSERC), the Trottier Family Foundation and the French National Research Agency (ANR).

Media Contacts 

Marie-Eve Naud
EPO Coordinator, Institute for Research on Exoplanets
Université de Montréal, Montréal, Canada
514-279-3222, marie-eve.naud@umontreal.ca

Scientific Contacts 

Stefan Pelletier (lead author)
Ph.D. Candidate, Institute for Research on Exoplanets
Université de Montréal, Montréal, Canada
stefan.pelletier@umontreal.ca  

Björn Benneke (co-author)
Professor, Institute for Research on Exoplanets
Université de Montréal, Montréal, Canada
514-578-2716, bjorn.benneke@umontreal.ca  

Additional links 

Scientific article (Astronomical Journal, open source version on arXiv.org)
Université de Montréal press release
Canada-France-Hawaii press release

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Scientists capture most-detailed radio image of Andromeda galaxy to date – UBC News

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‘Disk of galaxy’ identified as region where new stars are born

Scientists have published a new, detailed radio image of the Andromeda galaxy – the Milky Way’s sister galaxy – which will allow them to identify and study the regions of Andromeda where new stars are born.

Sofia Fatigoni

The study – which is the first to create a radio image of Andromeda at the microwave frequency of 6.6 GHz – was led by University of British Columbia physicist Sofia Fatigoni, with colleagues at Sapienza University of Rome and the Italian National Institute of Astrophysics. It was published online in Astronomy and Astrophysics.

“This image will allow us to study the structure of Andromeda and its content in more detail than has ever been possible,” said Fatigoni, a PhD student in the department of physics and astronomy at UBC. “Understanding the nature of physical processes that take place inside Andromeda allows us to understand what happens in our own galaxy more clearly – as if we were looking at ourselves from the outside.”

Prior to this study, no maps capturing such a large region of the sky around the Andromeda Galaxy had ever been made in the microwave band frequencies between one GHz to 22 GHz. In this range, the galaxy’s emission is very faint, making it hard to see its structure. However, it is only in this frequency range that particular features are visible, so having a map at this particular frequency is crucial to understanding which physical processes are happening inside Andromeda.

In order to observe Andromeda at this frequency, the researchers required a single-dish radio telescope with a large effective area. For the study, the scientists turned to the Sardinia Radio Telescope, a 64-metre fully steerable telescope capable of operating at high radio frequencies, located in Italy.

The Sardinia Radio Telescope, located in Sardinia, Italy. Credit: S. Fatigoni et al (2021)

The Sardinia Radio Telescope, located in Sardinia, Italy. Credit: S. Fatigoni et al (2021)

It took 66 hours of observation and consistent data analysis for the researchers to map the galaxy with high sensitivity.

They were then able to estimate the rate of star formation within Andromeda, and produce a detailed map that highlighted the ‘disk of the galaxy,’ as the region where new stars are born.

“By combining this new image with those previously acquired, we have made significant steps forward in clarifying the nature of Andromeda’s microwave emissions and allowing us to distinguish physical processes that occur in different regions of the galaxy,” said Dr. Elia Battistelli, a professor in the department of physics at Sapienza and coordinator of the study.

“In particular, we were able to determine the fraction of emissions due to thermal processes related to the early stations of new star formation, and the fraction of radio signals attributable to non-thermal mechanisms due to cosmic rays that spiral in the magnetic field present in the interstellar medium,” Fatigoni said.

Final image of the Andromeda galaxy after averaging over the whole bandwidth at 6.6 GHz. Credit: S. Fatigoni et al (2021)

Final image of the Andromeda galaxy after averaging over the whole bandwidth at 6.6 GHz. Credit: S. Fatigoni et al (2021)

For the study, the team also developed and implemented software that allowed them to test new algorithms to identify never-before-examined lower emission sources in the field of view around Andromeda at a frequency of 6.6 GHz.

From the resulting map, researchers were able to identify a catalog of about 100 ‘point sources’ including stars, galaxies and other objects in the background of Andromeda.

Interview language(s): English, Italian

Note for reporters: Sofia Fatigoni is based in Rome, Italy and is available for interviews until 3 p.m. PST.

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To help chart the cosmos, Western space researchers turn to crowd sourcing – CBC.ca

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Western University researchers have tapped the help of hundreds of amateur and professional astronomers in an effort to make sure no meteor is unable to slip by the Earth undetected.

To do that, they’re relying on the observations taken from 450 cameras in 30 different countries manned by “enthusiastic amateur astronomers” made up of professional and citizen scientists.

That data is then sent to Western University as part of what’s called the Global Meteor Network (GMN), headed by Denis Vida.

“So we have a lot of enthusiastic amateur astronomers, citizen scientists and also professionals that build, operate and maintain these cameras,” Vida told CBC’s Chris dela Torre during Afternoon Drive. “And every night they inspect the data set and send their data to a central server here at the University of Western Ontario.”

It’s not just about observing meteors – it’s about tracking what’s left of the ones that make it to the earth’s surface too.

“So we also observe a meteorite dropping fireballs,” said Vida. “They’re quite rare over an area of let’s say the country the size of France or Spain. Could only expect two to three of those fireballs a year that drop more than, let’s say, 300 grams of meteorites on the ground.”

“So because these events are very rare, it is important to observe 24/7.”

Vida explained that when one of their cameras spot one of them, they collect the data and find its location so they can retrieve what’s left for analysis – and analysis needs to happen quickly.  

“There are certain things in them, like some radionuclide to decay very quickly, but those can tell us how old the meteorite is, how long it was after it was ejected from the parent asteroid that it fell on the ground,” he said.

Vida explained that what ends up on the ground are just “several kilograms of materials” by the time they reach the earth’s surface. They aren’t hot either. They cool down on their descent.

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