2 Articles: Stargazing: Supermoons & Asteroid Bennu

Two Supermoons In August Mean Double The Stargazing Fun


Courtesy of Barrie360.comCanadian PressPublished: Jul 30th, 2023

By Marcia Dunn in Cape Canaveral, The Associated Press

The cosmos is offering up a double feature in August: a pair of supermoons culminating in a rare blue moon.

Catch the first show Tuesday evening as the full moon rises in the southeast, appearing slightly brighter and bigger than normal. That’s because it will be closer than usual, just 222,159 miles (357,530 kilometres) away, thus the supermoon label.

The moon will be even closer the night of Aug. 30 — a scant 222,043 miles (357,344 kilometres) distant. Because it’s the second full moon in the same month, it will be what’s called a blue moon.

“Warm summer nights are the ideal time to watch the full moon rise in the eastern sky within minutes of sunset. And it happens twice in August,” said retired NASA astrophysicist Fred Espenak, dubbed Mr. Eclipse for his eclipse-chasing expertise.

The last time two full supermoons graced the sky in the same month was in 2018. It won’t happen again until 2037, according to Italian astronomer Gianluca Masi, founder of the Virtual Telescope Project.

Masi will provide a live webcast of Tuesday evening’s supermoon, as it rises over the Coliseum in Rome.

“My plans are to capture the beauty of this … hopefully bringing the emotion of the show to our viewers,” Masi said in an email.

“The supermoon offers us a great opportunity to look up and discover the sky,” he added.

This year’s first supermoon was in July. The fourth and last will be in September. The two in August will be closer than either of those.

Provided clear skies, binoculars or backyard telescopes can enhance the experience, Espenak said, revealing such features as lunar maria — the dark plains formed by ancient volcanic lava flows — and rays emanating from lunar craters.

According to the Old Farmer’s Almanac, the August full moon is traditionally known as the sturgeon moon. That’s because of the abundance of that fish in the Great Lakes in August, hundreds of years ago.

‘Perfectly Excited’: Canadian Scientists Await First Look At Bits From Asteroid Bennu


Courtesy of Barrie360.com and Canadian PressPublished: Jul 29th, 2023

By Bob Weber

A group of Canadian scientists is awaiting the delivery of an outer space postcard from the past. 

On Sept. 24, seven years after it blasted off from its Florida launch pad, NASA’s OSIRIS-REx spacecraft is expected to drop a capsule into the Earth’s atmosphere containing matter plucked from the surface of an asteroid dating from the early history of the solar system.

“I’ve never worked with extraterrestrial material,” said Dominique Weis, a geoscientist at the University of British Columbia, who’s in line to get a tiny sample.

“I’m perfectly excited.”

The material comes from Bennu, previously known as near-Earth object 101955, a frozen chunk of rock about 500 metres across and roughly 450,000 kilometres from Earth. OSIRIS-REx has orbited within a couple hundred metres of its surface, scooped up a shovelful of it and is on its way home to drop off the package of whatever it found.

A Canadian-built set of lasers helped guide OSIRIS to its destination and produced a relief map of Bennu accurate to within a couple centimetres of height.

“In six weeks, we took data that provided the most detailed asteroid model ever,” said Michael Daly of York University’s Centre for Research in Earth and Space Science, who headed the team that designed the lasers. “You could see fractures and details in the rocks.

“We’re very proud of that.”

Bennu was chosen for several reasons.

It’s a doable distance. It’s large enough for a spacecraft to orbit — although OSIRIS set a record for the smallest orbit yet. And it’s considered “primitive,” relatively unmodified since its origin billions of years ago.  

That makes it a window into the early history of the solar system, said Weis.

“The idea is to go as far back in time as possible,” she said. 

Alan Hildebrand, a University of Calgary geoscientist, who is also to receive a Bennu bit, said that sheds light on Earth’s history as well.

“The Earth was formed by asteroids getting together,” he said. “Studying asteroids helps you understand the origins of our planet.”

Bennu can help answer questions such as how the early crust of the Earth formed, he said. 

As well, Bennu is from an area of space that cooled off well before the central part of what became the solar system, “freezing” those materials before they were altered by heat. And grabbing samples directly from the asteroid’s surface means scientists don’t have to account for the effects that flying through Earth’s atmosphere has on meteorites.

“The rocks comprising Bennu are from an older part of the solar system,” Hildebrand said. “We get to see the whole suite (of constituents) without the atmospheric filter.”

Finally, Bennu is thought to be rich in carbon. That could mean it contains organic compounds — those composed of carbon, hydrogen, oxygen and nitrogen.

Some scientists think those compounds could offer clues to how life began on Earth — although Hildebrand points out planets such as Mars and Venus are also showered with such material and don’t appear to host life.  

Bennu’s bits won’t be the first asteroid pieces brought to Earth. Two previous Japanese missions have brought back samples.

But the yield from OSIRIS is expected to be much larger. The Hayabusa missions brought back about five grams of asteroid — OSIRIS’s yield is estimated at anywhere between 60 grams and two kilograms.

“We’ll have more material to do more things,” Hildebrand said.  

Canadian scientists are getting samples of Bennu because of Canada’s $61-million investment in OSIRIS. But before any lab starts to warm up its mass spectrometer, NASA makes sure recipients know how to handle the precious grains, practising protocols on fragments of meteorites.

“We rehearse and rehearse and rehearse and rehearse some more,” said Weis. “We are working on the methods to be as sensitive and precise as possible.”

OSIRIS has already led to the publication of dozens of research papers. The arrival of its Bennu samples is expected to lead to many more.

The spacecraft also has enough fuel in its tank to take on more work after its return. 

OSIRIS-REx, renamed OSIRIS-APEX, is to head off to study Apophis, an asteroid roughly 370 metres in diameter that will come within 32,000 kilometres of Earth in 2029. The spacecraft will then use its thrusters to try to dislodge dust and small rocks on and below that asteroid’s surface.

OSIRIS will then send information on the rock’s behaviour back to Earth — its last assignment. 

Patricia Dent

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