Deep Space and Interplanetary Exploration - Houston, we are go for launch!

[worktroll]

We had rain & 100% clouds :(

[kato]

Since i haven't posted the pictures here yet at all, let's do it all at once...

All three chambers of the sample container of the return capsule of Hayabusa 2 have both been opened. Chamber B was empty as expected - only two out of three possible landings were performed after all. The contents have since been moved from the sample container to separate containers. The samples remain in a cleanroom environment.



Chamber A contains surface material from the first landing, mostly rather small granules of a few mm size.
 


Chamber C contains larger rocks - up to one cm diameter - from the second landing. This is subsurface material dug up by firing a space mine at the asteroid.

There was a "possible artificial object" in Chamber C, marked at the top left here. It has so far not been examined closely, but is considered to be likely aluminium foil dislodged from the sampler horn when Hayabusa 2 fired one of its guns at the asteroid to throw up material as part of the sampling process.



Free add-on sample: This is the bottom of the chamber in which the sample container was housed inside the return capsule. Finer dust escaped the sample container and collected at the bottom.

As a second freebie, Hayabusa 2 also brought back the first gas sample from deep space, first discovered during an initial opening of the return capsule in Australia. The gas is outgassing from the sample itself as it was being heated, mostly during reentry. The sample continued to outgas in ambient temperature, sufficiently enough for the same gas to be again present in noticable quantities during a second examination in Japan after a week.

[rebs]

https://cnn.it/3qzTRvF

The Perseverance rover has landed on Mars.

[Daryk]

Huzzah!  Another defeat for the ghoul...  ^-^

[Sabelkatten]

The robot invasion is proceding as planned...

[Wrangler]

View from the Sky Crane as its dropping off the Rover!

[marauder648]

https://www.youtube.com/watch?v=tHbU4Vk1kfA&ab_channel=SubBrief

This chap use to be a sonar man on USN subs so he knows his stuff when it comes to sound.

[Daryk]

Definitely a sonar tech... I think some of the comments on the video are correct, though.  The metallic noise is almost certainly something caused by the rover.  I agree with the comments that asserted NASA only filtered out the motor noises (some of the commenters are surely sonar techs too).

[rebs]

NASA has test fired the SLS booster in anticipation of a future moon mission.

https://www.space.com/nasa-sls-megarocket-engine-test-artemis-1-march-2021?utm_campaign=socialflow&utm_medium=social&utm_source=facebook.com&utm_content=space.com

[rebs]

Data from the Juno mission has uncovered a thin but fairly substantial cloud of orbital dust that leads to a phenomenon  called Zodiacal Light that slightly brightens the sky at, you guessed it, the Zodiac path. 

The culprit?  MARS.  And specifically the dust storms that rage on the surface.  Read more about it in the below link.

https://scitechdaily.com/serendipitous-juno-spacecraft-detections-shatter-ideas-about-origin-of-zodiacal-light/amp/

[Daryk]

It really makes you wonder if "dark matter" is just more of the usual stuff that we just haven't seen yet...

[Sabelkatten]

Data from the Juno mission has uncovered a thin but fairly substantial cloud of orbital dust that leads to a phenomenon  called Zodiacal Light that slightly brightens the sky at, you guessed it, the Zodiac path. 

The culprit?  MARS.  And specifically the dust storms that rage on the surface.  Read more about it in the below link.

https://scitechdaily.com/serendipitous-juno-spacecraft-detections-shatter-ideas-about-origin-of-zodiacal-light/amp/

Interplanetary dust is what Brian May wrote his thesis about. :) Rock on! ;D

[Sabelkatten]

It really makes you wonder if "dark matter" is just more of the usual stuff that we just haven't seen yet...

As I understand it that seems extremely unlikely. First off the required densities should be visible, second it should be distributed closer to how other matter is distributed. Dark matter, as far as we have been able to determine, doesn't interact through EM. That's how it stays dark and spreads out around galaxies.

[rebs]

Things to ponder and things to laugh about.

This thread is awesome!  :D

[marauder648]

I dunno if you folks have seen these, they're the Melodysheep video's, they do stuff that's like documentary worthy in terms of visuals

https://www.youtube.com/watch?v=6SrsZVdU740&t   - The history of the Moon

https://www.youtube.com/watch?v=SUelbSa-OkA&t   - Alien life and worlds vol 1

https://www.youtube.com/watch?v=ThDYazipjSI - alien life and worlds vol 2.

https://www.youtube.com/watch?v=uD4izuDMUQA - Timelaps of the future.

well worth a watch :)

[Daryk]

As I understand it that seems extremely unlikely. First off the required densities should be visible, second it should be distributed closer to how other matter is distributed. Dark matter, as far as we have been able to determine, doesn't interact through EM. That's how it stays dark and spreads out around galaxies.

The non-existence of "aether" was "extremely unlikely" until Michelson and Morely showed it to be so...

[rebs]

Somewhat related to the discussion...

https://www.space.com/magellanic-clouds-photo-dark-energy-camera

[Sabelkatten]

The non-existence of "aether" was "extremely unlikely" until Michelson and Morely showed it to be so...

While it's certainly possible there is a mundane explanation for dark matter, the situations aren't similar.

Before M&M there was no real evidence against the aether theory. However there is a lot of evidence against dark matter being just diffused normal matter - that was one of the first things investigated.

[worktroll]

Dark matter - the modern epicycles. Amazing how its properties change to meet the need of the latest theory? And no predictive, falsifiable work (proving a foregone selected conclusion ain't falsifiable).

But the modern thinking assumes it's either WIMPs or MACHOs - Weakly Interacting Massive Particles, or Massive Compact Halo Objects. Think is, if it's not magical, we'd see the effect on light travelling over billions of light years. And we don't. So it has to be magical, to keep that sweet, sweet grant money coming.

[Sabelkatten]

Dark matter - the modern epicycles. Amazing how its properties change to meet the need of the latest theory? And no predictive, falsifiable work (proving a foregone selected conclusion ain't falsifiable).

But the modern thinking assumes it's either WIMPs or MACHOs - Weakly Interacting Massive Particles, or Massive Compact Halo Objects. Think is, if it's not magical, we'd see the effect on light travelling over billions of light years. And we don't. So it has to be magical, to keep that sweet, sweet grant money coming.

Implying that thousands of physicists are all lying about their work to get more grant money is a rather serious accusation. Do you have any evidence to back that up?

As for the properties of dark matter - no one knows what the properties actually are. AFAIK, current knowledge is:

-Interacts with gravity.
-Not directly bound to visible matter.
-Minimal or no interaction with EM.

Plus a number of early hypothesis has been ruled out. But there's still something like a dozen possibly hypothesis left, including measurement errors, errors in general relativity, misunderstanding how cold ordinary matter will interact on a galactic scale, and so on.

[Natasha Kerensky]

we'd see the effect on light travelling over billions of light years. And we don't.

We do and have done so, for about a quarter century now.

Using spectroscopic data from the Sloan Digital Sky Survey, the SLACS1 team has so far isolated 98 ellipticals that strongly lens background blue star-forming galaxies at moderately high redshift (Bolton et al. 2008). Since the redshifts of both the lens and the background source are known, the lensing geometry, revealed by Hubble Space Telescope images (figure 4a), defines the total mass interior to the critical line (or ‘Einstein radius’) irrespective of whether that material is shining. Together with a dynamically based mass on a smaller physical scale derived from the dispersion of stellar velocities in the lensing galaxy itself, the total mass density in the lens as a function of galactocentric distance ρ(r) can be determined. Across a wide range in cosmic time and lens mass, the total mass distribution is remarkably uniform, following an isothermal distribution, Inline Formula (figure 4b). This distribution is spatially more extended than that of the visible baryons, demonstrating clearly the existence of dark matter...

Techniques for robustly analysing the pattern of distortions of background galaxies and inverting these to map the foreground dark matter were developed by Kaiser and others (Kaiser 1992; Kaiser et al. 1995). Yet the clear detection of weak lensing from the large-scale distribution of dark matter along random sight lines, an effect known as ‘cosmic shear’, was not announced until 2000 (Bacon et al. 2000; van Waerbeke et al. 2000; Wittman et al. 2000). There are excellent reviews of this rapidly developing field by Bartelmann & Schneider (2001), Huterer (2002) and Refregier (2003)...

The early papers (cited above) analysed the strength of the signal to constrain the amount of dark matter per unit volume, confirming independently values from other methods. Later papers exploited the capabilities of the Hubble Space Telescope to produce the first projected map of its distribution (Massey et al. 2007a; figure 7a). This map of dark matter can be compared with that of the light in the same direction as revealed by visible galaxies and X-ray clusters (figure 7b). To first order, there is a reassuring similarity, indicative of the fact that dark matter acts as the gravitational framework (or scaffolding) for the normal baryonic material...

In addition to tracing dark matter around clusters and on cosmic scales, a similar statistical technique can be applied around individual galaxies to detect their dark matter ‘haloes’. Suppose that we conduct a large spectroscopic survey of bright nearby galaxies and select a subset of systems of a particular class for which we have deeper imaging data. By ‘stacking’ the imaging data for that class of object, we can determine the average density of dark matter around a mean galaxy of this type to much larger radius than is possible using strong lensing (§3a(i)), and for a much wider variety of objects that may not be compact enough to act as strong lenses. Early detections of this so-called galaxy–galaxy lensingsignal were made by Brainerd et al. (1996).

The Sloan Digital Sky Survey (York et al. 2000) is a good example of a recent imaging and spectroscopic survey that has been used to analyse this signal (Fischer et al. 2000; Sheldon et al. 2004). By correlating the positions of foreground galaxies of a given type with the effect that they have on the shapes of background galaxies, we can not only measure the extent of their dark matter haloes for given types, but also determine the extent to which such galaxies are, or are not, representative tracers of the underlying dark matter density field. Such analyses can be used to determine the shapes of the dark matter haloes (Parker et al. 2007) as well as to eliminate claimed non-Newtonian gravitational forces laws invoked to eliminate the need for dark matter (Tian et al. 2009). Finally, by comparing the dark matter haloes associated with galaxies as a function of their spatial positions in dense clusters, we can demonstrate that galaxies suffer violent environmental forces that work to strip their dark matter haloes (Natarajan et al.2002, 2009).

Despite seemingly difficult technical obstacles only a few years ago, great strides have been made in using weak lensing to chart dark matter on large scales and around clusters and various galaxy populations. In the space of 3–4 years, we have confirmed the theoretical paradigm that emerged in the 1980s, which postulated that galaxies and clusters owe their existence to the gravitational clumping of a dominant dark matter density field. We can trace this dark matter around galaxies in statistically well-controlled samples and see how it differs in its extent and shape in various environments...

https://royalsocietypublishing.org/doi/10.1098/rsta.2009.0209

[Daryk]

To the "first order"?  I'm pretty sure Einstein was a few orders of magnitude beyond that (GPS, anyone?).  And I have to say, "gravitational framework (or scaffolding) for the normal baryonic material" sounds an awful lot like "universal metric" to me (no, it's not a perfect analogy, merely suspicious).

This is almost as much fun as debating Oxford commas, and I say that as a physicist (albeit one almost 28 years removed from their Astronomy minor).  I get a lot of observations have been made since I graduated, but I did stare at a lot of photographic plates as an undergrad.  I think there's still plenty of room for interpretation and error in that, modern technology notwithstanding.  Worktroll may have overstated his case, but he's not fundamentally wrong.

[Natasha Kerensky]

To the "first order"?  I'm pretty sure Einstein was a few orders of magnitude beyond that (GPS, anyone?).  And I have to say, "gravitational framework (or scaffolding) for the normal baryonic material" sounds an awful lot like "universal metric" to me (no, it's not a perfect analogy, merely suspicious).

This is almost as much fun as debating Oxford commas, and I say that as a physicist (albeit one almost 28 years removed from their Astronomy minor).  I get a lot of observations have been made since I graduated, but I did stare at a lot of photographic plates as an undergrad.  I think there's still plenty of room for interpretation and error in that, modern technology notwithstanding.  Worktroll may have overstated his case, but he's not fundamentally wrong.

Regardless of the impact of dark matter on galactic formation and distribution, to “first order” or otherwise, there is no doubt that otherwise undetectable matter is causing gravitational lensing effects.  There are too many lines of evidence across different lensing phenomena and objects and across too many teams and observatories to ascribe these effects to systemic error. 

Whether we’re spending too much on theory grants trying to come up with dark matter candidates and modeling their impact on early cosmological evolution, I’ll leave for other astrophysicists, armchair and otherwise, to debate.  But a statement that we have yet to observe the effects of dark matter on “light traveling over billions of light years” is grossly ignorant about our field and “fundamentally wrong”.  We have.  Repeatedly.  For a quarter century.

It’s the equivalent of claiming that medieval epicycle calculations are worthless because the planets never move retrograde.  An observed phenomenon exists whether or not we have a good explanation for it.

[PuppyLikesLaserPointers]

Well, personally, I didn't care about my lifespan seriously - I am not old enough to worry about that right now, and when I need to go then it is the time to go. Simple, as many people does since the dawn of our species(or lifeform in earth). I will eventually grow old, and finally on someday, die. It is just natural.

But when I read the information about the concept level project to launch the unmanned probe to the Alpha Centauri system some years ago, I am seriously wish that live long enough to see its result. We can get the report around 20~30 years after launch it, so how long I could live is a serious problem on it.

[marauder648]

Well, personally, I didn't care about my lifespan seriously - I am not old enough to worry about that right now, and when I need to go then it is the time to go. Simple, as many people does since the dawn of our species(or lifeform in earth). I will eventually grow old, and finally on someday, die. It is just natural.

But when I read the information about the concept level project to launch the unmanned probe to the Alpha Centauri system some years ago, I am seriously wish that live long enough to see its result. We can get the report around 20~30 years after launch it, so how long I could live is a serious problem on it.

And speaking of ligthening up, an awesome little vid about stars for ya'll

https://www.youtube.com/watch?v=3mnSDifDSxQ

[PuppyLikesLaserPointers]

https://en.wikipedia.org/wiki/File:Artist%27s_impression_of_the_evolution_of_a_hot_high-mass_binary_star.ogv

For lighten up, I like to keep playing it. ;D

[rebs]

Now to make things heavy again!  Lol...

Astronomers have imaged the magnetic field of the super-massive black hole in galaxy M87's core, the first such image of its kind.   Read more about this exciting development in the link below...

https://phys.org/news/2021-03-astronomers-image-magnetic-fields-edge.html

[Daryk]

Those are some fascinating and beautiful links folks... keep them coming!  :thumbsup:

[rebs]

Researchers have laid out a new theory about solar system  formation in the bubble of a supernova.  Pretty interesting read in the link below...

https://astronomy.com/news/2018/01/did-the-solar-system-form-in-a-bubble?utm_source=asyfb&utm_medium=social&utm_campaign=asyfb

[marauder648]

There's another Life beyond vid coming out by Melody Sheep and by the looks of it they're gonna do the Kardashev scale for Alien races

https://www.youtube.com/watch?v=dQ82y1ax1U0&ab_channel=melodysheep

The Kardashev scale's an interesting thing itself - https://en.wikipedia.org/wiki/Kardashev_scale