Connect with us

Science

Due to Precision Launch, NASA Says Webb Space Telescope's Fuel Likely To Last Way More Than 10 Years – SciTechDaily

Published

 on


NASA’s James Webb Space Telescope. Credit: NASA’s Goddard Space Flight Center Conceptual Image Lab

After a successful launch of <span aria-describedby="tt" class="glossaryLink" data-cmtooltip="

NASA
Established in 1958, the National Aeronautics and Space Administration (NASA) is an independent agency of the United States Federal Government that succeeded the National Advisory Committee for Aeronautics (NACA). It is responsible for the civilian space program, as well as aeronautics and aerospace research. It’s vision is "To discover and expand knowledge for the benefit of humanity."

“>NASA’s <span aria-describedby="tt" class="glossaryLink" data-cmtooltip="

James Webb Space Telescope
The James Webb Space Telescope (JWST or Webb) is an orbiting infrared observatory that will complement and extend the discoveries of the Hubble Space Telescope. It covers longer wavelengths of light, with greatly improved sensitivity, allowing it to see inside dust clouds where stars and planetary systems are forming today as well as looking further back in time to observe the first galaxies that formed in the early universe.

“>James Webb Space Telescope on December 25, and completion of two mid-course correction maneuvers, the Webb team has analyzed its initial trajectory and determined the observatory should have enough propellant to allow support of science operations in orbit for significantly more than a 10-year science lifetime.  (The minimum baseline for the mission is five years.)

Ariane 5 Rocket Launches Webb Space Telescope

Arianespace’s Ariane 5 rocket launches with NASA’s James Webb Space Telescope onboard, Saturday, December 25, 2021, from the ELA-3 Launch Zone of Europe’s Spaceport at the Guiana Space Centre in Kourou, French Guiana. The James Webb Space Telescope (sometimes called JWST or Webb) is a large infrared telescope with a 21.3 foot (6.5 meter) primary mirror. The observatory will study every phase of cosmic history—from within our solar system to the most distant observable galaxies in the early universe. Credit: NASA/Bill Ingalls

The analysis shows that less propellant than originally planned for is needed to correct Webb’s  trajectory toward its final orbit around the second Lagrange point known as L2, a point of gravitational balance on the far side of Earth away from the Sun. Consequently, Webb will have much more than the baseline estimate of propellant – though many factors could ultimately affect Webb’s duration of operation.

Webb has rocket propellant onboard not only for midcourse correction and insertion into orbit around L2, but also for necessary functions during the life of the mission, including “station keeping” maneuvers – small thruster burns to adjust Webb’s orbit — as well as what’s known as momentum management, which maintains Webb’s orientation in space.

The extra propellant is largely due to the precision of the Arianespace Ariane 5 launch, which exceeded the requirements needed to put Webb on the right path, as well as the precision of the first mid-course correction maneuver – a relatively small, 65-minute burn after launch that added approximately 45 mph (20 meters/sec) to the observatory’s speed.  A second correction maneuver occurred on December 27, adding around 6.3 mph (2.8 meters/sec) to the speed.

The <span aria-describedby="tt" class="glossaryLink" data-cmtooltip="

accuracy
How close the measured value conforms to the correct value.

“>accuracy of the launch trajectory had another result: the timing of the solar array deployment. That deployment was executed automatically after separation from the Ariane 5 based on a stored command to deploy either when Webb reached a certain attitude toward the Sun ideal for capturing sunlight to power the observatory – or automatically at 33 minutes after launch. Because Webb was already in the correct attitude after separation from the Ariane 5 second stage, the solar array was able to deploy about a minute and a half after separation, approximately 29 minutes after launch.

From here on, all deployments are human-controlled so deployment timing – or even their order — may change. Explore what’s planned here.

Adblock test (Why?)



Source link

Continue Reading

Science

Consistent Asteroid Collisions Rock Previous Thinking on Mars Impact Craters – SciTechDaily

Published

 on


This image provides a perspective view of a triple crater in the ancient Martian highlands. Credit: ESA/DLR/FU Berlin

New Curtin University research has confirmed the frequency of asteroid collisions that formed impact craters on <span aria-describedby="tt" class="glossaryLink" data-cmtooltip="

Mars
Mars is the second smallest planet in our solar system and the fourth planet from the sun. Iron oxide is prevalent in Mars’ surface resulting in its reddish color and its nickname "The Red Planet." Mars’ name comes from the Roman god of war.

“>Mars has been consistent over the past 600 million years.

New Curtin University research has confirmed the frequency of asteroid collisions that formed impact craters on Mars has been consistent over the past 600 million years.

The study, published in Earth and Planetary Science Letters, analyzed the formation of more than 500 large Martian craters using a crater detection algorithm previously developed at Curtin, which automatically counts the visible impact craters from a high-resolution image.

Despite previous studies suggesting spikes in the frequency of asteroid collisions, lead researcher Dr. Anthony Lagain, from Curtin’s School of Earth and Planetary Sciences, said his research had found they did not vary much at all for many millions of years.

Impact Craters on Mars

One of the 521 large craters that has been dated in the study. The formation age of this 40km crater has been estimated using the number of small craters accumulated around it since the impact occurred. A portion of these small craters are shown on the right panel and all of them have been detected using the algorithm. In total, more than 1.2 million craters were used to date the Martian craters. Credit: Curtin University

Dr. Lagain said counting impact craters on a planetary surface was the only way to accurately date geological events, such as canyons, rivers, and volcanoes, and to predict when, and how big, future collisions would be.

“On Earth, the erosion of plate tectonics erases the history of our planet. Studying planetary bodies of our Solar System that still conserve their early geological history, such as Mars, helps us to understand the evolution of our planet,” Dr. Lagain said.

“The crater detection algorithm provides us with a thorough understanding of the formation of impact craters including their size and quantity, and the timing and frequency of the asteroid collisions that made them.”

Past studies had suggested that there was a spike in the timing and frequency of asteroid collisions due to the production of debris, Dr. Lagain said.

“When big bodies smash into each other, they break into pieces or debris, which is thought to have an effect on the creation of impact craters,” Dr. Lagain said.

“Our study shows it is unlikely that debris resulted in any changes to the formation of impact craters on planetary surfaces.”

Co-author and leader of the team that created the algorithm, Professor Gretchen Benedix, said the algorithm could also be adapted to work on other planetary surfaces, including the Moon.

“The formation of thousands of lunar craters can now be dated automatically, and their formation frequency analyzed at a higher resolution to investigate their evolution,” Professor Benedix said.

“This will provide us with valuable information that could have future practical applications in nature preservation and agriculture, such as the detection of bushfires and classifying land use.”

Reference: “Has the impact flux of small and large asteroids varied through time on Mars, the Earth and the Moon?” by Anthony Lagain, Mikhail Kreslavsky, David Baratoux, Yebo Liu, Hadrien Devillepoix, Philip Bland, Gretchen K. Benedix, Luc S. Doucet and Konstantinos Servis, 7 January 2022, Earth and Planetary Science Letters.
DOI: 10.1016/j.epsl.2021.117362

Adblock test (Why?)



Source link

Continue Reading

Science

B.C. researchers uncover mechanism that keeps large whales from drowning while feeding on krill – CTV News Vancouver

Published

 on


Vancouver –

New research from the University of British Columbia is shedding light on the ways that whales feed underwater without flooding their airways with seawater.

The research, published this month in Current Biology, shows that lunge-feeding whales – the type that lunge and gulp at large schools of krill – have a special mechanism in the back of their mouths that stops water from entering their lungs when eating.

“It’s kind of like when a human’s uvula moves backwards to block our nasal passages, and our windpipe closes up while swallowing food,” says lead author Dr. Kelsey Gil, a postdoctoral researcher in the department of zoology, in a statement.

Specifically, a fleshy bulb acts as a plug, to close off upper airways, while a larynx closes to block lower airways.

The humpback whale and the blue whale are both lunge-feeders, but the scientists’ research focused on fin whales, thanks in part to being able to travel to Iceland in 2018 and examine carcass remains at a commercial whaling station.

“We haven’t seen this protective mechanism in any other animals, or in the literature. A lot of our knowledge about whales and dolphins comes from toothed whales, which have completely separated respiratory tracts, so similar assumptions have been made about lunge-feeding whales,” Gil said.

Lunge-feeders are impressive, Gil said, because sometimes the amount of food and water they consume is larger than their bodies. After snapping at krill, and while blocking the water from their airways, the whales then drain the ocean water through their baleen, leaving behind the tasty fish.

The study’s senior author Dr. Robert Shadwick, a professor in the UBC department of zoology, says the efficiency of the whales’ feeding is a key factor in their evolution.

“Bulk filter-feeding on krill swarms is highly efficient and the only way to provide the massive amount of energy needed to support such a large body size. This would not be possible without the special anatomical features we have described,” he said in a statement. 

Adblock test (Why?)



Source link

Continue Reading

Science

Study confirmed the frequency of asteroid collisions that formed Mars craters – Tech Explorist

Published

 on


Mapping and counting impact craters are the most commonly used technique to derive detailed insights on geological events and processes shaping the surface of terrestrial planets. Scientists from Curtin University have used a crater detection algorithm to analyze the formation of more than 500 large Martian craters.

The algorithm they used automatically counts the visible impact craters from a high-resolution image. Scientists found that the frequency of asteroid collisions that formed Mars craters has been consistent for over 600 million years.

Lead scientist Dr. Anthony Lagain from Curtin’s School of Earth and Planetary Sciences said, “Despite previous studies suggesting spikes in the frequency of asteroid collisions, this research had found they did not vary much at all for many millions of years.”

“Counting impact craters on a planetary surface was the only way to accurately date geological events, such as canyons, rivers, and volcanoes, and to predict when, and how big, future collisions would be.”

“On Earth, the erosion of plate tectonics erases the history of our planet. Studying planetary bodies of our Solar System that still conserve their early geological history, such as Mars, helps us to understand the evolution of our planet.”

“The crater detection algorithm provides us with a thorough understanding of the formation of impact craters, including their size and quantity, and the timing and frequency of the asteroid collisions that made them.”

“Past studies had suggested that there was a spike in the timing and frequency of asteroid collisions due to the production of debris.”

“When big bodies smash into each other, they break into pieces of debris, which is thought to affect the creation of impact craters.”

“Our study shows it is unlikely that debris resulted in any changes to the formation of impact craters on planetary surfaces.”

Co-author and leader of the team that created the algorithm, Professor Gretchen Benedix, said“the algorithm could also be adapted to work on other planetary surfaces, including the Moon.”

“The formation of thousands of lunar craters can now be dated automatically, and their formation frequency analyzed at a higher resolution to investigate their evolution.”

“This will provide us with valuable information that could have future practical applications in nature preservation and agriculture, such as the detection of bushfires and classifying land use.”

Journal Reference:

  1. Anthony Lagain et al. Has the impact flux of small and large asteroids varied through time on Mars, the Earth, and the Moon? DOI: 10.1016/j.epsl.2021.117362

Adblock test (Why?)



Source link

Continue Reading

Trending