Tag: science

Sunspot update: The Sun continues to boom!

12:02 pm

It is time for my monthly sunspot update, taking NOAA’s most recent update of its monthly graph tracking the number of sunspots on the Sun’s Earth-facing hemisphere and adding my own analysis as well as some additional details to provide the larger context.

During August the Sun continued to confound the experts, with the number of sunspots not only greater than July’s high count. the August count exceeded the numbers from December 2001 (215.5 vs 213.4), the last time the Sun was this active.

None of the predictions by anyone in the solar science community had predicted this level of activity.
» Read more

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A galaxy with a halo and a stupendous central black hole

9:22 am

A galaxy with a halo and a stupendous black hole
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken by the Hubble Space Telescope as part of a survey of galaxies that have what astronomers call active galactic nuclei (AGNs). This galaxy, dubbed IC 4709, is about 240 million light years away.

If IC 4709’s core were just filled with stars, it would not be nearly so bright. Instead it hosts a gargantuan black hole, 65 million times the mass of our Sun. A disc of gas spirals around and eventually into this black hole, with the gas crashing together and heating up as it spins. It reaches such high temperatures that it emits vast quantities of electromagnetic radiation, from infrared to visible to ultraviolet light and beyond — in this case including X-rays. The AGN in IC 4709 is obscured by a lane of dark dust, just visible at the centre of the galaxy in this image, which blocks any optical emission from the nucleus itself.

To get a very vague sense of scale, this supermassive black hole is more than sixteen times more massive than the relatively inactive supermassive black hole in the center of the Milky Way. This imagery and data from Hubble will help astronomers better understand the interaction between the black hole and its surrounding galaxy.

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Due to thruster problem, the Mercury orbiter BepiColombo will arrive at Mercury almost one year late

9:05 am

The joint ESA and JAXA Mercury mission BepiColombo will now reach its destination eleven months late because its ion electric thrusters are producing less thrust than expected.

The spacecraft is actually made up of two orbiters, one built by the European Space Agency (ESA) and the second built by Japan’s space agency JAXA. During launch and the journey to Mercury each is attached to a third spacecraft called the Mercury Transfer Module (MTM), which has the large electric ion thrusters used for making the mid-course corrections prior to and after each fly-by of the Earth (once), Venus (twice), and Mercury (six) before finally entering orbit around Mercury. It has already completed the Earth, Venus and three Mercury fly-bys.

In April 2024 engineers discovered that during a mid-course correction on April 26st the MTM’s thrusters failed to produce the desired thrust.

Engineers identified unexpected electric currents between MTM’s solar array and the unit responsible for extracting power and distributing it to the rest of the spacecraft. Onboard data imply that this is resulting in less power available for electric propulsion. ESA’s BepiColombo Mission Manager, Santa Martinez explains: “Following months of investigations, we have concluded that MTM’s electric thrusters will remain operating below the minimum thrust required for an insertion into orbit around Mercury in December 2025.”

In order not to lose the mission entirely, the science team has come up with a new trajectory that will have it fly past Mercury on its fourth fly-by on September 4, 2024 only 103 miles above the surface, 22 miles closer than originally planned. This will give it a larger slingshot speed boost to help make up for the under-powered thrusters. It will then make its planned fifth and sixth Mercury fly-bys in December ’24 and January ’25, the adjusted route having it arrive in Mercury orbit eleven months later than planned, in November 2026.

This new plan however means that the pictures taken this week during the Mercury fly-by will provide some nice high resolution details, far better than those produced by the earlier fly-bys.

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A cliff of ice on Mars

12:56 pm

A cliff of ice on Mars
Click for original image.

Cool image time! The picture to the right, cropped to post here, was taken on April 10, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows the southern nose of a large plateau located in the deep south of Mars, at 63 degrees south latitude. This cliff is only about 20-25 feet high, but within that small distance orbital imagery as revealed what appears to be an underground layer of ice. When this photo was released in late June, it came with a short caption, which noted:

On these steep scarps, ice can still be seen on the south facing walls of the scarp towards the end of the Southern Hemisphere’s winter.

Note the white sections on that cliff wall, both inside and outside the color strip. The surrounding orange suggests dust and sand. This photo suggests that during the dark winter underground ice leaches out on these slopes, and is then sublimated away when the Sun returns in the spring. Since the south-facing walls remain in shadow the longest, the ice there lasts the longest, leaving behind these patches we see now.

It is also possible that this is not water ice and there is no underground ice layer. Instead, this might be the last leftover of the dry ice mantle that falls as snow and covers all of the Martian high latitudes during the winter, and then sublimates away come spring.
» Read more

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First New Glenn launch, set for October 13, 2024, only has an 8-day launch window

9:16 am

According to an article from Aviation Week today, in order for Blue Origin’s New Glenn rocket to get its payload of two Mars orbiters on their way to Mars it must launch within a very short window lasting only eight days, beginning on the present launch date of October 13, 2024.

The Oct. 13-21 launch window is an ambitious goal. The aft and mid modules of New Glenn’s reusable first stage were recently attached, clearing the path for installation of the vehicle’s seven methane-fueled BE-4 engines, CEO Dave Limp noted in an Aug. 23 update on the X social media site.

A static hot-fire at New Glenn’s Florida launch complex is planned prior to launch. The company did not release the status of the New Glenn upper stage, which is to be powered by a pair of BE-3U engines fueled by liquid oxygen and liquid hydrogen. A hot-fire of the second stage is also pending.

This launch will be the first ever for New Glenn. To get ready for that tight launch window it appears a great deal of work must be done in the next six weeks, some of which Blue Origin engineers will be doing for the very first time.

If there are any issues and that launch window is missed, the two NASA Escapade orbiters, built by Rocket Lab, will face a two-year delay until the next window to get to Mars re-opens. At that point New Glenn will likely do this launch with a dummy payload, since it needs to get off the ground in order to fulfill other launch contracts, including a 27-launch contract with Amazon for its Kuiper satellite constellation.

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Changing Martian slope streaks

12:27 pm

Changing slope streaks on Mars
Click here, here, and here for original images.

Overview map

Time for some cool images from Mars taken over a dozen years! The three pictures above were taken, from left to right, in 2012, 2020, and 2024 and show the same exact Martian terrain. The first two pictures were photographed by the lower resolution context camera on Mars Reconnaissance Orbiter (MRO). The rightmost picture was taken on May 20, 2024 by MRO’s high resolution camera.

The white dot on the overview map to the right marks the location, in the middle of the vast lava flood plains found between Mars’ giant volcanos and north of the Medusae Fossae Formation, the largest volcanic ash deposit on Mars. The 1,200-foot-high mesa pictured above, its peak indicated by the red dot, is part of a group of such mesas that either represent the peaks of a mountain range now mostly buried by lava, or volcanic vents pushed up when those eruptions were occurring more than a billion years ago.

The focus of these pictures however is not volcanism, but the numerous slope streaks seen on the mesa slopes. Note how the 2012 earliest streaks are still visible in 2024, but have faded. Note also how there appears to have been no new streaks since 2020.

Slope streaks are a geological feature unique to Mars that at the moment remain unexplained. At first glance they appear to be a landslide of some kind, but years of orbital study has shown they do not change the topography at all, they never have debris piles at their base, and the streaks even sometimes actually flow up and over small rises in the slopes. They occur randomly throughout the year, and as seen above, over time fade.

Recent research has suggested their formation is related to dust avalanches triggered by dust storms, conclusions that are strengthened by the fact that slope streaks are generally found on dusty slopes, which in this case makes sense as the location is in the dry Martian tropics. That these dust avalanches do not change the topography at all, merely staining it, while sometimes actually flowing up and over rises, illustrates how Mars’ one-third gravity and thin, cold atmosphere makes things happen that are impossible on Earth.

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NASA leans toward launching Europa Clipper as scheduled, despite transistor issue

9:26 am

Though the final decision will be made in early September, NASA revealed today in a short post that management is leaning towards launching the multi-billion Europa Clipper mission as scheduled on October 10, 2024, despite a very recently discovered transistor issue where the transistors were not properly hardened in construction for the harsh radiation environment surrounding Jupiter.

The next major milestone for Clipper is Key Decision Point E on Monday, Sept. 9, in which the agency will decide whether the project is ready to proceed to launch and mission operations. NASA will provide more information at a mission overview and media briefing targeted for that same week.

The Europa Clipper mission team recently conducted extensive testing and analysis of transistors that help control the flow of electricity on the spacecraft. Analysis of the results suggests the transistors can support the baseline mission. [emphasis mine]

The highlighted sentence suggests NASA officials have weighed the option between launching on time with a limited ability to do science once at Jupiter versus delaying the launch years to fix the transistors, and are now favoring the former option. The cost of delay would be high and long, and NASA officials might believe the bad press for that option would be much greater than a mission that only achieves its bare minimum results. For example, to admit publicly that NASA installed transistors that were not space-hardened when that necessity has been known about since the 1960s would be as embarrassing to the agency as it was for Boeing when it discovered it had installed flammable tape in its Starliner capsule. NASA management might be leaning to letting a flawed multi-billion dollar project launch, knowing its capabilities are quite limited, in order to avoid that embarrassment.

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Evidence of Martian near-surface ice in an unusual location

11:48 am

Evidence of Martian near-surface ice in an unusual location
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on May 27, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). Labeled merely as a terrain sample, it was likely taken not as part of any specific research request, but to fill a gap in the camera’s picture-taking schedule so as to maintain its proper temperature.

The picture however shows features that help confirm earlier research into the near-surface ice believed to permeate Mars’ middle latitudes. The knobby flat terrain both inside and outside of the crater resembles what scientists have labeled “brain terrain”, an as-yet unexplained geological feature unique to Mars and usually associated with near-surface ice and the glacial features found above 30 degrees latitude.

This 1.4-mile-wide unnamed crater is located at 40 degrees north latitude, so expecting near-surface ice or glacial features here is not unreasonable. The location however is different for other reasons, that make this data more intriguing.
» Read more

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Webb finds six exoplanets, all flying in interstellar space without a star

11:11 am

Astronomers using the Webb Space Telescope have discovered six different planets ranging in mass 5 to 10 times that of Jupiter, all unattached to any star or solar system.

The most intriguing of the starless objects is also the lightest, having an estimated mass of five Jupiters (about 1,600 Earths). The presence of a dusty disk means the object almost certainly formed like a star, as space dust generally spins around a central object in the early stages of star formation, said Langeveld, a postdoctoral researcher in Jayawardhana’s group.

All of these starless planets likely formed like this one, coalescing like a star does but unlike a star never having enough mass to ignite.

The astronomers are next going to attempt to detect the atmosphere’s of these rogue exoplanets, though it is not clear exactly how they will do this unless one of the exoplanets just happened to transit across a more distant star, something that simply does not happen very often.

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A real whirlpool in space

9:52 am

A real whirlpool in space
Click for original image.
Cool image time! The picture above, cropped to post here, was taken by the Hubble Space Telescope as part of a survey of nearby galaxies that have what astronomers call an Active Galactic Nuclei (AGN), because the supermassive black hole at the center is devouring nearby material at a great rate and thus producing high energy emissions as it does so.

Many active galaxies are known to astronomers at vast distances from Earth, thanks to the great brightness of their nuclei highlighting them next to other, dimmer galaxies. At 128 million light-years from Earth, UGC 3478 is positively neighbourly to us. The data used to make this image comes from a Hubble survey of nearby powerful AGNs found in relatively high-energy X-rays, like this one, which it is hoped can help astronomers to understand how the galaxies interact with the supermassive black holes at their hearts.

The bottom line is that this spiral galaxy literally is a whirlpool, the entire galaxy spiralling down into that massive black hole in its center. One cannot help wondering why such galaxies don’t end up eventually getting completely swallowed by that black hole.

Or maybe they do, and we don’t see such things because all that is left is a supermassive black hole that emits no light or energy at all, a dark silent ghost traveling between the galaxies unseen and undetectable.

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First high resolution images released from Juice’s fly-by of the Earth & Moon

9:34 am

Juice's high resolution view of the Moon
Click for original image.

The Italian science team that runs the high resolution camera on the asteroid probe Juice have now released that camera’s first images, taken to test its operation during the spacecraft’s close fly-by of both the Moon and then the Earth a week ago.

The picture to the right, cropped, reduced, and sharpened to post here, shows the Moon’s surface during that close fly-by, which got within 435 miles. The camera is dubbed Janus, and was developed by Italy and operated by the Italian National Institute for Astrophysics.

JANUS will study global, regional and local features and processes on the moons, as well as map the clouds of Jupiter. It will have a resolution up to 2.4 m per pixel on Ganymede and about 10 km per pixel at Jupiter.

The main aim of JANUS’s observations during the lunar-Earth flyby was to evaluate how well the instrument is performing, not to make scientific measurements. For this reason, JANUS took images with various camera settings and time intervals – a bit like if you’re going out to test a DSLR camera for the first time. In some cases, researchers intentionally ‘blurred’ the images so that they can test out resolution recovery algorithms. In other cases, they partially saturated the image to study the effects induced on the unsaturated areas.

As can be seen by the sample image above, the test images appear to have demonstrated that Janus will function as planned when Juice arrives in orbit around Jupiter in 2031 in order to study that gas giant’s upper atmosphere as well as its larger icy moons, Ganymede, Calisto, and Europa.

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Finding beauty on Mars in all the strange places

12:08 pm

Overview map

Beauty on Mars
Click for original image.

Cool image time! The picture to the right, cropped to post here, was taken on May 23, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The white dot in the inset of the overview map above indicates the location on Mars, smack dab in the middle of the 2,000-mile-long mid-latitude strip that I call glacier country, because practically every close-up image of this region shows glacial features.

This picture is no exception. The arrows in the inset show the downhill grade, falling about 1,700 feet across the entire inset. That grade is a reflection of the transition that takes place in this glacier country from the cratered southern highlands to the northern lowland plains.

I decided to crop the image at full resolution — showing only a tiny portion — because to my eye these curving linear grooves, produced naturally as Mars’ climate cycles cause glaciers to shrink and then grow repeatedly so that each cycle lays down a new line while squeezing the previous lines, are almost like a work of art. This might be nothing more than a glacier on an alien planet, but nature has caused it to form a very beautiful picture.

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