Year: 2023

Monitoring the gullies on Mars for changes

12:54 pm

Monitoring the gullies on Mars
Click for original image.

Cool image time! The picture to the right, cropped and reduced to post here, was taken on March 24, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO) as part of a long term monitoring program of the many Martian gullies scientists have found above 30 degrees north latitude on a variety of slopes.

Martian gullies are small, incised networks of narrow channels and their associated downslope sediment deposits, found on the planet of Mars. They are named for their resemblance to terrestrial gullies. First discovered on images from Mars Global Surveyor, they occur on steep slopes, especially on the walls of craters. Usually, each gully has a dendritic alcove at its head, a fan-shaped apron at its base, and a single thread of incised channel linking the two, giving the whole gully an hourglass shape. They are estimated to be relatively young because they have few, if any craters.

…Most gullies occur 30 degrees poleward in each hemisphere, with greater numbers in the southern hemisphere. Some studies have found that gullies occur on slopes that face all directions; others have found that the greater number of gullies are found on poleward facing slopes, especially from 30° to 44° S. Although thousands have been found, they appear to be restricted to only certain areas of the planet. In the northern hemisphere, they have been found in Arcadia Planitia, Tempe Terra, Acidalia Planitia, and Utopia Planitia. In the south, high concentrations are found on the northern edge of Argyre basin, in northern Noachis Terra, and along the walls of the Hellas outflow channels.

Orbital data has identified almost 5,000 gullies on Mars. Based on their shape and the Martian climate, scientists generally think these gullies were formed by some form of water flow, possibly coming from an underground aquifer at their top.
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Scientists increasingly put politics over uncertainty in their research papers

10:35 am

The modern scientific method
The modern scientific method

The death of uncertainty in science: According to a paper published this week in the peer-review journal Science, scientists in recent years are increasingly abandoning uncertainty in their research papers and are instead more willing to make claims of absolute certainty without hesitation or even proof.

If this trend holds across the scientific literature, it suggests a worrisome rise of unreliable, exaggerated claims, some observers say. Hedging and avoiding overconfidence “are vital to communicating what one’s data can actually say and what it merely implies,” says Melissa Wheeler, a social psychologist at the Swinburne University of Technology who was not involved in the study. “If academic writing becomes more about the rhetoric … it will become more difficult for readers to decipher what is groundbreaking and truly novel.”

The new analysis, one of the largest of its kind, examined more than 2600 research articles published from 1997 to 2021 in Science, which the team chose because it publishes articles from multiple disciplines. (Science’s news team is independent from the editorial side.) The team searched the papers for about 50 terms such as “could,” “appear to,” “approximately,” and “seem.” The frequency of these hedging words dropped from 115.8 instances per 10,000 words in 1997 to 67.42 per 10,000 words in 2021.

Those numbers represent a 40% decline, a trend that has been clear for decades, first becoming obvious in the climate field. » Read more

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Euclid’s first images look good

9:19 am

Scientists have determined that the first test images from the two cameras on the recently launched orbiting Euclid space telescope are sharp and as expected.

Both VIS and NISP provided these unprocessed raw images. Compared to commercial products, the cameras are immensely more complex. VIS comprises 36 individual CCDs with a total of 609 megapixels and produces high-resolution images of billions of galaxies in visible light. This is how astronomers determine their shape. The first images already give an impression of the abundance that the data will provide.

NISP’s detector consists of 16 chips with a total of 64 megapixels. It operates in the near-infrared at wavelengths between 1 and 2 microns. In addition, NISP serves as a spectrograph, which splits the light of the captured objects similar to a rainbow and allows for a finer analysis. These data will allow the mapping of the three-dimensional distribution of galaxies.

Knowing that 3D distribution will allow scientists to better determine the nature of both dark energy (related to the acceleration of the universe’s expansion) and dark matter (related to an undiscovered mass that affects the formation and shape of galaxies).

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India officials confirm Australian beach debris comes from an old PSLV rocket

9:12 am

Officials from India’s space agency ISRO have confirmed that the large metal cylinder that washed up on an Australian beach on July 16th came from an old PSLV rocket, which which one remains at present unknown.

“We have concluded the object located on a beach near Jurien Bay in Western Australia is most likely debris from an expended third-stage of a Polar Satellite Launch Vehicle (PSLV). The PSLV is a medium-lift launch vehicle operated by ISRO,” the space agency tweeted.

A day after the object surfaced on July 16, the ISRO had confirmed to HT that the object was a part of PSLV upper stage but an old one. ISRO chairman S Somanath had said, “This is a part of PSLV upper stage but an old one. It is not from a recent mission, it must be older.” PSLV’s third stage is a solid rocket motor that provides upper stages high thrust after the atmospheric phase of launch.

If this came from an upper stage, it means it survived re-entry far better than expected, and then survived floating the the ocean for a long period. Since it does not appear as yet that the agency has determined which launch the object came from, we do not know how long.

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India’s PSLV rocket places seven satellites into orbit

6:23 pm

India today (July 30th in India) successfully used its PSLV rocket to put seven satellites into orbit, launching from its coastal Satish Dhawan spaceport. This was the first time since India panicked over COVID and shut down in 2020 that the country has managed two launches within one month.

The leaders in the 2023 launch race:

51 SpaceX
30 China
9 Russia
6 Rocket Lab (with a launch planned for later tonight. Live stream here— Launch aborted at T-0)
6 India

American private enterprise still leads China in successful launches 58 to 30, and the entire world combined 58 to 50, with SpaceX by itself leading the entire world (excluding American companies) 51 to 50.

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Momentus completes deployment of all payloads launched on board its Vigoride-6 tug

9:14 am

Momentus yesterday announced that it has successfully completed deployment of all the payloads that were launched in April on its Vigoride-6 orbital tug.

So far, in three demonstration missions in fourteen months, the company has deployed fifteen customer satellites using its Vigoride tug, though two were sent into an incorrect orbit because of a “human error in the mapping of a software command.”

The company next two missions are presently scheduled to be launched in November 2023 and February 2024.

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ESA successfully completes controlled re-entry of its Aeolus satellite

9:07 am

Engineers for the European Space Agency (ESA) yesterday successfully completed the controlled re-entry of its Aeolus satellite above Antarctica, where it burned up in the atmosphere.

The spacecraft would never have hit the ground had its re-entry — which would have happened anyway in just a matter of weeks — been allowed to happen in an uncontrolled manner. However, ESA decided to use the satellite to practice disposal techniques it wishes to make standard for all future satellites, especially those whose orbit keeps them in space long after their mission is finished.

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SpaceX’s Falcon Heavy successfully launches the heaviest geosynchronous communications satellite ever

8:15 pm

SpaceX tonight successfully used its Falcon Heavy rocket to place a Hughes geosynchronous communications satellite into orbit, the heaviest ever, lifting off from Cape Canaveral.

The two side boosters successfully completed their third flight, landing back at Cape Canaveral only a few seconds apart. The rocket’s two fairing halves completed their fifth and sixth flights. The center core stage was not recovered as planned.

The leaders in the 2023 launch race:

51 SpaceX
30 China
9 Russia
6 Rocket Lab

American private enterprise still leads China in successful launches 58 to 30, and the entire world combined 58 to 49, with SpaceX by itself leading the entire world (excluding American companies) 51 to 49.

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July 28, 2023 Quick space links

3:22 pm

Courtesy of BtB’s stringer Jay.

 

 

 

 

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