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Supernovae are one of the most useful events in all of astronomy. Scientists can directly measure their power, their spin, and their eventual fallout, whether that’s turning into a black hole or a neutron star in some cases or just a much smaller stellar remnant. One of these events happened around 350 years ago (or around 11,000 years ago from the star’s perspective) in the constellation Cassiopeia. The James Webb Space Telescope recently caught a glimpse of the aftereffects of the explosion, and it happened to shed light (literally) on a familiar area of study – interstellar gas.

The supernova in Cassiopeia ejected a massive amount of X-rays and ultraviolet light into the area surrounding the now-dead star. That energy is now hitting a clump of gas gathered in the interstellar medium about 350 light years from the star. An effect called a “light echo” is created in the process.

A light echo can be thought of as a giant photographer’s bulb. A bright flash (i.e., the energy from the supernova) travels in an ever-extending sphere outwards, gradually illuminating everything in its path, then moving on and leaving the objects it just passed back in darkness. As the material is illuminated, telescopes back on Earth can see this otherwise invisible matter existing in the interstellar medium.

Evolution of the lit-up gas and dust cloud over the course of months.
Credit – STScI YouTube Channel

The Cassiopeia A explosion caused dozens of light echoes, but one in particular caught the attention of astronomers. From our perspective, gas and dust located past the now-dead star have been gradually lit up as the flash from the supernova passes through it, creating a spectacular image.

Spitzer, one of NASA’s great observatories that ended its observations in 2020, examined this same clump of gas and dust back in 2008. Its image was fascinating but not as complete as the one by its successor, JWST.

The image from JWST, admittedly falsely colored since humans can’t see infrared light, is spectacular, both aesthetically and scientifically. It shows a series of “sheets” that are remarkably small for an interstellar structure, measuring only about 400 AU across. They seem to be influenced by interstellar magnetic fields, as video of still images shows them twisting and writhing around.

Image from Spitzer of the dust cloud taken in 2008.
Credit – NASA / JPL-Caltech / Y. Kim (U of Arizona / U of Chicago)

Another feature of the image is described as “knots in wood grain” in a press release from the Webb telescope researchers. It also twists and moves over months as if dragged by some invisible force.

Light echoes can also be seen in the visible light range. However, infrared wavelengths, which are better thought of as the heat emitted from this gas and dust as the light echo passes through it, are more capable of showing the 3D structure as the wavelengths themselves aren’t blocked by the dust as visible light would be.

Consistently taking images over the course of months also provides another advantage. As Armin Rest of the Space Telescope Science Institute puts it, “We have three slices taken at three different times,” comparing the layered result as equivalent to a CT scan commonly used in medicine.

Context for the area of the image in the Cassiopeia
Credit – NASA / ESA / CSA / STScI

While the first picture from these studies might be fantastic, there is plenty of science left to do on these clouds of matter. Future work will continue to watch as the supernova flash-bulb illuminates and darkens different parts of the collected material. Some of that might even be destroyed, as the high-power supernovae that are strong enough to cause infrared light echoes could potentially vaporize some of the matter it hits.

JWST will continue to monitor the evolving situation, but a helping hand is coming. The Nancy Grace Roman Space Telescope, due to launch in 2027, will help scan the sky for evidence of other infrared light echoes. JWST will then follow up with closer observations using its powerful infrared instruments. If we’re lucky, we’ll see plenty more astonishing pictures soon, like the ones released last week.

Learn More:
Webb Space Telescope – NASA’s Webb Reveals Intricate Layers of Interstellar Dust, Gas
UT – A Fast-Moving Star is Colliding With Interstellar gas, Creating a Spectacular bow Shock
UT – Local Interstellar Gas Mapped in 3-D
UT – A Black Hole Has Cleared Out Its Neighbourhood

The post Webb Sees Light Echoes in a Supernova Remnant appeared first on Universe Today.

The video of Day 1 of our “Censorship in the Sciences” conference is up (and down below), and this baby is nearly seven hours long.  Few people have the patience to listen to the first day’s sessions all at 0ne go, but I want to single out a few talks. The first is by Jonathan Rauch, author of The Constitution of Knowledge: A Defense of Truth, an excellent book. His talk begins at 12:01, outlines how knowledge acquisition should work, and is quite eloquent.

Later, the four-member panel on “Examples of Censorship” gives a good account of how ideology has led to suppression of science.  Luana introduces it at 2:43:26 and Lawrence Krauss kicks it off at 2:44:45 via Zoom. His examples are numerous and disturbing—and not just from physics.  He pulls no punches, and even calls out America’s National Academy of Sciences (NAS), the most prestigious honorary organization of scientists in the U.S. It so happened that the NAS President (Marcia McNutt) was in the audience, and heard Krauss call out her organization for identity-based choosing of candidates for a supposedly meritocratic society (see 2:55:45). As Krauss shows, the NAS even admitted this explicitly in a quote from an executive of the organization, and it’s widely admitted by Academy members themselves. (Note that at the end of her later talk, at 4:39:30, President McNutt denies this. accusing Krauss implicitly of ignorance, but her own organization’s stated policies belie her words.)  Finally, Krauss gives evidence that both the NSF and DOE have likewise been captured by ideology in their funding of grants.

If you want to hear about how indigenous peoples are preventing anthropologists and forensic scientists from studying relics likes bones and objects used by Native Americans, Elizabeth Weiss’s short talk in that panel, beginning at 3:23:43,  gives a good idea. She has a new book about these issues.

I heard all the talks, and some of the others engaged me as well, but I’ve just mentioned the ones I enjoyed the most.

Here is the first day’s schedule (from here)

And here’s some of the press as detailed by Heterodox at USC:

Press Coverage

Censorship in the Sciences conference speakers call on peers to organize, defend free speech, writes Jennifer Kabbany in The College Fix.

Rauch’s opening speech highlighted surveys which found that almost half of Americans think that colleges have a negative effect on the country.

“It really is a crisis,” he said, adding a combination of factors are to blame, including students’ emotional fragility, the politicization of hiring, tenure and funding based on ideology, and a newer trend of academic journals refusing to publish findings that allegedly harm some communities.

Kabbany also covered Musa al-Gharbi’s presentation at the conference. Read that article here.

Alice Dreger, managing editor at the Heterodox Academy, wrote a recap on HxA’s Free the Inquiry Substack:

On the issue of censorship of research publication, many speakers at the conference objected to the idea that claims about potential harm to vulnerable populations should be used as a reason to stop, force changes to, or retract research reports. Some raised the question of the harms that arise from alleged-harm-reduction censorship–that is, the harms that arise from stopping valuable research out of fear of harm

In response to a Saturday morning presentation by Nature editor Stavroula Kousta, journalist Jesse Singal, also a speaker at our event, published a critique of some the ideas presented.

Conference organizer and panelist Lee Jussim wrote about the conference (and whether we should just burn academia down).

Panelist Jerry Coyne wrote several dispatches about the conference on his blog Why Evolution is True (which reaches nearly 75,000 readers).

Attendee Zvi Shalem wrote up his take-ways from the conference here.

Panelist Michael Bowen of Free Black Thought reflected on attending conference on his Substack.

Natalya Murakhver wrote about her experience debuting her documentary 15 Days at the conference.

Panel chair Abhishek Saha wrote up excellent Twitter threads (in real time!) detailing conference proceedings. Here is one on the first day of conference.

Is 8 hours of sleep really the right amount for you? Understanding your personal chronotype could be a better way to approach how much time you should spend in bed

There really is a significant mystery in the world of cosmology. This, in my opinion, is a good thing. Such mysteries point in the direction of new physics, or at least a new understanding of the universe. Resolving this mystery – called the Hubble Tension – is a major goal of cosmology. This is a scientific cliffhanger, one which will unfortunately take years or even decades to sort out. Recent studies have now made the Hubble Tension even more dramatic.

The Hubble Tension refers to discrepancies in measuring the rate of expansion of the universe using different models or techniques. We have known since 1929 that the universe is not static, but it is expanding. This was the famous discovery of Edwin Hubble who notice

d that galaxies further from Earth have a greater red-shift, meaning they are moving away from us faster. This can only be explained as an expanding universe – everything (not gravitationally bound) is moving away from everything else. This became known as Hubble’s Law, and the rate of expansion as the Hubble Constant.

Then in 1998 two teams, the Supernova Cosmology Project and the High-Z Supernova Search Team, analyzing data from Type 1a supernovae, found that the expansion rate of the universe is actually accelerating – it is faster now than in the distant past. This discovery won the Nobel Prize in physics in 2011 for  Adam Riess, Saul Perlmutter, and Brian Schmidt. The problem remains, however, that we have no idea what is causing this acceleration, or even any theory about what might have the necessary properties to cause it. This mysterious force was called “dark energy”, and instantly became the dominant form of mass-energy in the universe, making up 68-70% of the universe.

I have seen the Hubble Tension framed in two ways – it is a disconnect between our models of cosmology (what they predict) and measurements of the rate of expansion, or it is a disagreement between different methods of measuring that expansion rate. The two main methods of measuring the expansion rate are using Type 1a supernovae and by measuring the cosmic background radiation. Type 1a supernovae are considered standard candle because they have roughly the same absolute magnitude (brightness). The are white dwarf stars in a binary system that are siphoning off mass from their partner. When they reach a critical point of mass, they go supernova. So every Type 1a goes supernova with the same mass, and therefore the same brightness. If we know an object’s absolute magnitude of brightness, then we can calculate its distance. It was this data that lead to the discovery that the universe is accelerating.

But using our models of physics, we can also calculate the expansion of the universe by looking at the cosmic microwave background (CMB) radiation, which is the glow left over after the Big Bang. This gets cooler as the universe expands, and so we can calculate that expansion by looking at the CMB close to us and farther away. Here is where the Hubble Tension comes in. Using Type 1a supernovae, we calculate the Hubble Constant to be 73 km/s per megaparsec. Using the CMB the calculation is 67 km/s/Mpc. These numbers are not close enough – they are very different.

At first it was thought that perhaps the difference is due to imprecision in our measurements. As we gather more and better data (such as building a more complete sample of Type 1a supernovae), using newer and better instruments, some hoped that perhaps these two numbers would come into alignment. The opposite has happened – newer data has solidified the Hubble Tension.

A recent study, for example, uses the Dark Energy Spectroscopic Instrument (DESI) to make more precise measurements of Type 1a’s in the nearby Coma cluster. This is used to make a more precise calibration of our overall measurements of distance in the universe. With this more precise data, the authors argue that the Hubble Tension should now be considered a “Hubble Crisis” (a term which then metastasized throughout reporting headlines). The bottom line is that there really is a disconnect between theory and measurements.

Even more interesting, another group has used updated Type 1a supernovae data to argue that perhaps dark energy does not have to exist at all. This is their argument: The calculation of the Hubble Constant throughout the universe used to establish an accelerating universe is based on the assumption of isotropy and homogeneity at the scale we are observing. Isotropy means that the universe is essentially the same density no matter which direction you look in, while homogeneity means that every piece of the universe is the same as every other piece. So no matter where you are and which direction you look in, you will observe about the same density of mass and energy. This is obviously not true at small scales, like within a galaxy, so the real question is – at what scale does the universe become isotropic and homogenous? Essentially cosmologists have used the assumption of isotropy and homogeneity at the scale of the observable universe to make their calculations regarding expansion. This is called the lambda CDM model (ΛCDM), where lambda is the cosmological constant and CDM is cold dark matter.

This group, however, argues that this is not true. There are vast gaps with little matter, and matter tends to clump along filaments in the universe. If instead you take into account these variations in the density of matter throughout the universe, you get different results for the Hubble Constant. The primary reason for this is General Relativity. This is part of Einstein’s (highly verified) theory that matter affects spacetime. Where matter is dense, time relatively slows down. This means as we look out into the universe, the light that we see is travelling faster through empty space than it is through space with lots of matter, because that matter is causing time to slow down. So if you measure the expansion rate of the universes it will appear faster in gaps and slower in galaxy clusters. As the universe expands, the gaps expand, meaning the later universe will have more gaps and therefore measure a faster acceleration, while the older universe has smaller gaps and therefore measures a slower expansion. They call this the timescape model.

If the timescape model is true, then the expansion of the universe is not accelerating (it’s just an illusion of our observations and assumptions), and therefore there is no need for dark energy. They further argue that their model is a better fit for the data than ΛCDM (but not by much). We need more and better data to definitively determine which model is correct. They are also not mutually exclusive – timescape may explain some but not all of the observed acceleration, still leaving room for some dark energy.

I find this all fascinating. I will admit I am rooting for timescape. I never liked the concept of dark energy. It was always a placeholder, but also just has properties that are really counter-intuitive. For example, dark energy does not dilute as spacetime expands. This does not mean it is false – the universe can be really counterintuitive to us apes with our very narrow perspectives. I will also follow whatever the data says. But wouldn’t it be exciting if an underdog like timescape overturned a Nobel Prize winning discovery, and for at least a second time in my lifetime radically changed how we think about cosmology. Timescape may also resolve the Hubble Tension to boot.

Whatever the answer turns out to be – clearly there is something wrong with our current cosmology. Resolving this “crisis” will expand our knowledge of the universe.

The post The Hubble Tension Hubbub first appeared on NeuroLogica Blog.

Today’s photos come from mathematician and Hero of Intellectual Freedom Abby Thompson of UC Davis, whose avocation is photographing California tide pools and their invertebrates. Abby’s captions are indented, and you can enlarge her photos by clicking on them.

New year’s tidepool pictures from Dillon Beach in northern California, plus a few older photos.  It’s not that much colder during the winter here- August can be freezing, December delightful.   To see much in December you have to be willing to go out after dark, which is a little spooky, but has the advantage that you often get to see racoons foraging on the rocks.    Sadly the only pictures I get of them look like two red dots (their eyes) on a black background.

As usual I got help with some of the IDs from people on inaturalist.

Schuchertinia milleri (tentative):

This is through a microscope, taken with my iphone.  In the tidepools it appears as a small very pink blob stuck to a rock. These are hydroids, closely related to jellyfish, unlikely as that seems.

Kelp crab:

These crabs are one of the few things you should be cautious about in the tidepools here- they are reported to have a strong bite with their claws (I haven’t tested this), and they’re not shy.

The next four pictures are all nudibranchs. As you can see, their coloration is quite varied, but nevertheless they are all the same species. Keep this in mind for when we get to pictures 7,8 and 9.

Triopha maculata 1:

 

Triopha maculata 2:

 

Triopha maculata 3:

 

Triopha maculata 4:

 

Ok, the next two pictures are two distinct species of nudibranch.    To my eye, the difference in coloration here is a bit more subtle than for the Triophas; H. crassicornis has white “stripes” on the frilly stuff on its back.

Hermissenda opalescens:

Hermissenda crassicornis:

And the next picture is of these two local species of Hermissenda hanging out together.  Not exactly in flagrante (nudibranchs spend an awful lot of their time mating and laying eggs), but still, looking pretty friendly. Maybe Jerry will chime in with some info on delimiting species?  and how exactly it is done, for us non-experts. [JAC: two different forms copulating doesn’t resolve their species status!]

Hermissenda opalescens and Hermissenda crassicornis:

Clam siphons:

There is not enough appreciation of bivalves in the world, except as dinner,  Their siphons can be lovely (I admit this may be in the eye of the beholder).

Coryphella trilineata:

A pretty nudibranch. There are lots of this species at the moment.

Pycnogonid stearnsi:

There are several species of “sea spiders” locally.   They’re small (this one was less than an inch across), and lively.      This is the most common here.

Anthopleura artemisia (Moonglow anemone):

You may remember from earlier pictures that this is another species with many dramatically different color variants.

Camera info:  Mostly Olympus TG-7, in microscope mode, pictures taken from above the water.

Countries like the UK, Spain and Italy rely on gas to step in when renewables can’t produce power, leading to higher energy prices – but a more flexible system could avoid this

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Even as President Donald Trump is inaugurated today and his pick for HHS Secretary, Robert F. Kennedy, Jr. prepares to face confirmation hearings, there is trouble in "make America healthy" paradise.

The post Trouble in (MAHA) paradise? first appeared on Science-Based Medicine.

Here is a live video of a group of Israelis watching the release of three of the hostages, Romi Gonen, Emily Damari and Doron Steinbrecher, captured during the October 7 massacre. They are all young women, and of course they are alive.  We know that some families will be getting their relatives in boxes, which is ineffably sad, but today we can rejoice at this reunion of the living.

The released:

(From the NYT): Undated handout photographs from the Hostages Families Forum Headquarters of the freed hostages Romi Gonen, left, Emily Damari, center, and Doron Steinbrecher.Credit…The Hostages Families Forum

This will be the next-to-last item I write about my entanglement with the Freedom From Religion Foundation (FFRF)—I hope.

I am pretty sure that the joint statement below resulted from the fracas that ensued after the FFRF took down my post about biological sex, followed by my resignation and those of Richard Dawkins and Steve Pinker—all of us members of the FFRF’s Honorary Board.  This censorship didn’t look good, and although some blogging miscreants defended the FFRF’s claim that what I wrote was “harmful”, the real press didn’t make the FFRF’s censorship look so good.  Further, the organization then simply dissolved its entire honorary board of 15 remaining members. The FFRF’s announcement of that, below, actually comes from an Intelligent Design site run by the Discovery Institute:

Here’s the announcement from the FFRF site (archived here as well); rectangle is mine:

and from the Intelligent Design site Mind Matters:

They really need some competent people to run their website, even more so because there’s still a page listing the entire Honorary Board. Oy!  I suspect the “Mind Matters” citation will be removed within a day or so. (This reminds me of the “”cdesign proponentsists” vestigial wording found by Barbara Forrest and revealed during the Dover Trial as evidence that “Intelligent Design” was simply a recasting of creationism.)

At any rate, the FFRF got together with 16 other humanist organizations to issue a joint statement that is below, and which you can find here .  The words are indented below the headline. I have bolded three passages.

As the 119th Congress and state legislative sessions begin across the nation — and the incoming Trump-Vance administration prepares to take office — the extreme White Christian nationalist movement and their politician enablers have made it clear that LGBTQ-plus Americans, particularly trans people, will be singled out for discrimination, exclusion and attacks in 2025. Indeed, this dangerous movement has made anti-LGBTQ rhetoric and policies a cornerstone of their agenda.

As organizations committed to protecting the separation of government and religion, as well as universal human and civil rights threatened by the White Christian nationalist ideology, the undersigned organizations reaffirm our commitment to forcefully advocate for the rights of LGBTQ-plus Americans, create inclusive and welcoming communities, represent the interests of our diverse constituents, and act in accordance with our values.

We will not permit religious extremists to foment a moral panic, encourage harassment or violence, and enact dangerous policies that seek to force LGBTQ-plus Americans generally — and trans Americans in particular — out of public life and out of existence. Nor will we sit silently or ignore when the talking points, misinformation and outright fabrications of anti-LGBTQ-plus extremists are laundered and given a veneer of legitimacy or acceptability by those who hold themselves out as voices of reason or science.

In just the past year, we have seen book bans forcing libraries and schools to remove materials that even mention LGBTQ-plus characters; bathroom bans and “bounty” laws that threaten harassing lawsuits or even criminal prosecution against trans Americans simply for using the restroom; religious refusal laws allowing medical providers to deny treatment; outright bans on a range of medical care for gender dysphoria, substituting the judgement of state governments for that of patients, parents, and physicians; and even investigations threatening to remove trans and gender nonconforming children from their families. More of the same is coming in 2025.

For the more than 1.5 million trans Americans, this is the reality they are forced to live every day. It is not merely some academic debate.

These unworkable, ill-conceived and plainly discriminatory laws and policies are about one thing: forcing a regressive, largely religious view of gender norms onto the American people. They are “solutions” in search of a problem that simply doesn’t exist. Instead, the extremists advocating for these actions intend to send a clear message that trans Americans are not worthy of dignity or respect — and their cruel and dehumanizing rhetoric only confirms that intention. We cannot and will not ignore such bigotry, no matter its source.

Instead, we stand with our trans members, supporters, and constituents. We will continue to advocate for policies that protect the civil and human rights of every community that comes under threat from the White Christian nationalist ideology. And we will ensure that the inherent dignity and worth of all people is respected within our community and beyond.

American Atheists
Nick Fish
President
American Humanist Association
Fish Stark
Executive Director
Association of Secular Elected Officials
Leonard Presberg
President
Black Nonbelievers
Mandisa Thomas
President
Camp Quest
Alyssa Fuller
Executive Director
The Clergy Project
Duane Grady
President
Freedom From Religion Foundation
Dan Barker & Annie Laurie Gaylor
Co-Presidents
Freethought Society
Margaret Downey
President
Hispanic American Freethinkers
David Tamayo
President
Military Association of Atheists & Freethinkers
Jason Torpy
President
Recovering From Religion
Gayle Jordan
Executive Director
Secular Student Alliance
Kevin Bolling
Executive Director
Secular Coalition for America
Steven Emmert
Executive Director
Secular Woman
Monette Richards
President
Society for Humanistic Judaism
Paul Golin
Executive Director
Unitarian Universalist Humanist Association
Leika Lewis-Cornwell
President

Now I largely agree with this statement! As I have made clear many times, I think that LGBTQ+ individuals deserve exactly the same rights and dignity afforded to everyone else, save for a few areas in which the rights of such people (mostly of the “T” persuasion rather than the other letters) clash with the rights of other groups. But singling out these few areas (like sports or hormones given to children) gets one called a “transphobe”. So be it. I am not sure whether the organizations above approve of things like infusing children with hormones, proselytizing them with “affirmative” therapy, or allowing a biological male who self-identifies as a woman to compete in women’s athletics. If they wouldn’t, then we largely agree!  But they don’t tell us.

Further, it is not just “White Christian Nationalists” who are wary of giving unlimited rights to trans people. A new NYT poll, summarized here, shows that the American public in general has pushed back against the two trans rights I mentioned above.  Here’s a summary of the NYT data, divided by political affiliation. As you see nearly 80% of Americans, including 67% of Democrats, don’t think that trans female athletes should be able to compete in women’s sports.  These are clearly not all “White Christian Nationalists”!  For these people, as for me, the views on sports reflect a simple concern of fairness for women. And the concerns about drugs and hormone therapy on minors comes from the fact that we don’t know the long-term effects of these drugs plus people should be of a certain age (I think about 18 or 21) before they can decide whether to take hormone therapy or surgery to assume some secondary traits of their non-natal sex. There are, after all, permanent effects of such treatment that require a certain maturity to grasp and understand.

As for “White Christian Nationalists,” well, I suspect that many people of color share the attitudes given in the tables above.  Where does the “White” come from? Are there no Christian Nationalists of Color? And, of course, neither I nor, I suspect, most of the Democrats (or even Republicans) mentioned above, are Christian Nationalists.  In fact, as far as I see, their views seem to me to be based on ethics, not religion! But it is in the interest of humanist organizations to blame religion for every ideological or ethical view they don’t like, as it keeps the members and money flowing in.

Finally, I have no doubt about one thing: the statement below was aimed at me, Steve Pinker, and Richard Dawkins:

Nor will we sit silently or ignore when the talking points, misinformation and outright fabrications of anti-LGBTQ-plus extremists are laundered and given a veneer of legitimacy or acceptability by those who hold themselves out as voices of reason or science.

I stand by my “talking points”, affirm that sex in humans is binary, and reject assertions that “a woman is whoever she says she is.” If that is not misinformation, then I’m a monkey’s uncle (actually, I’m a monkey’s relative).

As one reader emailed me, and I quote with permission:

[The FFRF] apparently canvassed other humanist/atheist organizations and got them to endorse the statement as well, though I’d guess at least some those organizations viewed it as a boilerplate expression of support for those communities and weren’t aware of FFRF’s larger agenda. This is a textbook and quite literal case of “virtue signalling” — a full-throated declaration that they are the virtuous ones, complete with a strenuous denunciation of heretics to demonstrate that virtue. It’s incredible, and incredibly disappointing to see this level of ideological and (frankly) religious capture within the allegedly-secular community.

Now I don’t know if the FFRF instigated this group statement, but, as I said, I’m pretty sure that it wouldn’t have been issued had I not written my short essay (archived here) that was taken down after a day by the FFRF.

Now, onto what seems to be one of the few remaining secular/skeptical organizations that remains sensible: the Center for Inquiry. Click to read. It was written by Robyn Blumner, the President and CEO

The text:

January 17, 2025

The Center for Inquiry (CFI) stands for reason, science, and secularism and has been doing so for nearly fifty years.

We are often the speakers of inconvenient truths: There is no evidence that you will see your departed loved one in a place called heaven. There is no evidence that a loving god is answering your prayers. Ancient indigenous medicine is not on a par with western medicine. GMO crops are not harmful per se and can be hugely beneficial.

Lately, there has been a disagreement among secular groups with regard to transgender activism. As disagreements go, this one is rather narrow, though it has been made to seem gigantic.

Biological science indicates there are two biological sexes, a fact consistent throughout the animal world of which humans are a part. There is also a more fluid concept of gender that allows for a more complex picture of human sexuality. Both things can be true at the same time. There can be two biological sexes and multiple gender identities. And when public policy is enacted, it should be sensitive to the former as well as the latter.

This appears to be an inconvenient truth in light of the response by some secular groups.

Some secular groups are taking the position that any discussion of biological facts is transphobic and a denial of civil and human rights. They posit that giving reasons for understanding the natural world as a place divided into biological male and female members of species isn’t just a scientific discussion but a cover for full-on Christian nationalism.

CFI is opposed to Christian nationalism in all its guises. And to the extent Christian nationalists have used transgender issues to gin up outrage and make gains politically for their agenda of injecting religion into public policy, we are opposed.

None of that changes biological facts or the complexities of the issues involved. Good people of good will should be willing to grapple with these complexities without imputing bad motives for divergent views.

For instance, if there is a medical clinical trial for women to determine if a medication has a different impact on women than men, should transgender women participate? If transgender women are to be considered the same as natal women, the answer is “yes” they should participate. However, science suggests otherwise, because they are not biologically the same.

Saying as much doesn’t make you a tool of Christian nationalism.

There are other places where the biology of sex has a significant role to play. In sports, for instance. Once male puberty has occurred, it is no longer fair physiologically for whoever has benefited from it to compete in almost any category of women’s sports. At least that is what the science and evidence demonstrate.

One of the most contested areas involves transitioning minors before they reach the age of majority. In light of the latest research and actions by several European countries that have stepped back from such medical interventions, the way “gender-affirming care” is practiced in the United States is no longer universally accepted as the most beneficial approach. There are increasing numbers of detransitioners, whether transgender activists want to believe it or not, and those stories can be just as heartbreaking as the stories of transgender-identifying children seeking medical intervention.

To elide past these complex issues and claim that only one side involves civil and human rights is simply wrong. Natal women athletes have civil rights as well. Children have human rights that include not having permanent disabling surgeries before they truly understand the consequences.

Those who think these and other areas are open to rational, scientific, evidence-based debate are not laundering the fabrications of Christian nationalists as has been charged. They are recognizing that these are not simple matters of right and wrong and that the full panoply of interests at stake should be considered.

But if the conversation is over before it even begins, if any crack of daylight between one’s point of view and that of the most extreme transgender activist is considered hateful bigotry and shall not be uttered without fear of cancellation, then that is a place where reason and science have disappeared and all that remains is vitriol, anger, and self-righteousness.

That won’t happen at CFI.

CFI will continue to promote the separation of church and state, the rights of nonbelievers here and around the world, and the end of pseudoscience wherever it arises. And we strongly disagree with people or groups who think discussion is dangerous, biology is bigotry, and science is Christian nationalism in disguise.

Robyn E. Blumner,
CEO and President, Center for Inquiry
Executive Director, Richard Dawkins Foundation for Reason & Science

This is eminently rational, and I have nothing to add to it.  But I have to repeat this part, which I especially like:

But if the conversation is over before it even begins, if any crack of daylight between one’s point of view and that of the most extreme transgender activist is considered hateful bigotry and shall not be uttered without fear of cancellation, then that is a place where reason and science have disappeared and all that remains is vitriol, anger, and self-righteousness.

That won’t happen at CFI.

No, it won’t happen at CFI—not as long as they steer the course that Robyn describes.

While I continue to admire the work that the FFRF does in keeping church and state separate, I will no longer support them financially given their new ideology and behavior. Instead, my donations will go to the Center for Inquiry as the sole secular/skeptical organization I support.  If you have rescinded membership in the FFRF, I would suggest that you simply give that money to the CFI, which will need it since it may lose some donors over this fracas.

We’re back to readers’ wildlife, and I have about five days’ worth, but please send in your photos. Today being Sunday, we’re featuring the photos of John Avise, who has moved from birds to butterflies. John’s captions are indented, and you can enlarge his photos by clicking on them.

Butterflies in North America, Part 6 

This week continues my many-part series on butterflies that I’ve photographed in North America.  I’m continuing to go down my list of species in alphabetical order by common name.

Dorantes Longtail (Urbanus dorantes), topwing:

Dorantes Longtail, underwing:

Dotted Blue (Euphilotes enoptes):

Dotted Blue, underwing:

Dun Skipper (Euphyes vestris):

Eastern Comma (Polygonia comma):

Eastern Comma, underwing:

Eyed Brown (Satyrodes eurydice):

Eyed Brown, another specimen:

Field Crescent (Phyciodes pulchella), topwing:

Field Crescent, underwing:

Fiery Skipper (Hylephila phyleus), male topwing:

Fiery Skipper, male underwing:

Fiery Skipper, female topwing:

Fiery Skipper, female underwing:

The exoplanet census continues to grow. Currently, 5,819 exoplanets have been confirmed in 4,346 star systems, while thousands more await confirmation. The vast majority of these planets were detected in the past twenty years, owing to missions like the Kepler Space Telescope, the Transiting Exoplanet Survey Satellite (TESS), the venerable Hubble, the Convection, Rotation and planetary Transits (CoRoT) mission, and more. Thousands more are expected as the James Webb Space Telescope continues its mission and is joined by the Nancy Grace Roman Space Telescope (RST).

In the meantime, astronomers will soon have another advanced observatory to help search for potentially habitable exoplanets. It’s called Pandora, a small satellite that was selected in 2021 as part of NASA’s call for Pioneer mission concepts. This observatory is designed to study planets detected by other missions by studying these planets’ atmospheres of exoplanets and the activity of their host stars with long-duration multiwavelength observations. The mission is one step closer to launch with the completion of the spacecraft bus, which provides the structure, power, and other systems.

Funded by NASA’s Astrophysics Pioneers, Pandora is a joint effort between Lawrence Livermore National Laboratory in California and NASA’s Goddard Space Flight Center. The mission will study planets detected by other observatories that rely on Transit Photometry (aka. the Transit Method), where astronomers monitor stars for periodic dips in brightness that indicate the presence of orbiting planets. Pandora will then monitor these planets for future transits and obtain spectra from their atmospheres – a process known as Transit Spectroscopy.

Using this method, scientists can determine the chemical composition of exoplanet atmospheres and search for indications of biological activity (aka. “biosignatures”). During its year-long primary mission, the SmallSat will study 20 stars and their 39 exoplanets in visible and infrared light. The mission team anticipates Pandora will observe at least 20 exoplanets 10 times for 24 hours, during which transits will occur, and the satellite will obtain spectra from the exoplanets’ atmospheres.

In particular, Pandora will be looking to determine the presence of hazes, clouds, and water. The data it obtains will establish a firm foundation for interpreting measurements by Webb and future missions to search for habitable worlds. Daniel Apai, a co-investigator of the mission, is a professor of astronomy and planetary sciences at the U of A Steward Observatory and Lunar and Planetary Laboratory, who leads the mission’s Exoplanets Science Working Group. As he said in a U of A News release:

“Although smaller and less sensitive than Webb, Pandora will be able to stare longer at the host stars of extrasolar planets, allowing for deeper study. Better understanding of the stars will help Pandora and its ‘big brother,’ the James Webb Space Telescope, disentangle signals from stars and their planets.” 

The concept for the telescope emerged to address a specific problem with Transit Spectroscopy. During transits, telescopes capture far more than just the passing through the planet’s atmosphere. They also capture light from the star itself. In addition, stellar surfaces are not uniform and have hotter, brighter regions (faculae) and cooler, darker regions (stellar spots) that change in size and position as the star rotates. This produces “mixed signals” that make it difficult to distinguish between light passing through the planet’s atmosphere and light from the star – which can mimic the signal produced by water.

Pandora will disentangle these signals by simultaneously monitoring the host star’s brightness in visible and infrared light. These observations will provide constraints on the variations in the star’s light, which can used to separate the star’s spectrum from the exoplanet’s. With the completion of the spacecraft bus, Pandora is one step closer to launch thanks to the completion of the spacecraft bus, which provides the structure, power, and other systems vital to the mission.

The completion of the bus was announced on January 16th during a press briefing at the 245th Meeting of the American Astronomical Society (AAS) in National Harbor, Maryland. “This is a huge milestone for us and keeps us on track for a launch in the fall,” said Elisa Quintana, Pandora’s principal investigator at NASA’s Goddard Space Flight Center. “The bus holds our instruments and handles navigation, data acquisition, and communication with Earth — it’s the brains of the spacecraft.” Said Ben Hord, a NASA Postdoctoral Program Fellow who discussed the mission at the 245 AAS:

“We see the presence of water as a critical aspect of habitability because water is essential to life as we know it. The problem with confirming its presence in exoplanet atmospheres is that variations in light from the host star can mask or mimic the signal of water. Separating these sources is where Pandora will shine.”

“Pandora’s near-infrared detector is actually a spare developed for the Webb telescope, which right now is the observatory most sensitive to exoplanet atmospheres. In turn, our observations will improve Webb’s ability to separate the star’s signals from those of the planet’s atmosphere, enabling Webb to make more precise atmospheric measurements.”

Unlike Webb and other flagship missions, Pandora can conduct continuous observations for extended periods because the demand for observation time will be low by comparison. Therefore, the Pandora satellite will fill a crucial gap between exoplanet discovery provided by flagship missions and exoplanet characterization. The mission is also a boon for the University of Arizona since Pandora’s science working group is led from there, and Pandora will be the first mission to have its operations center at the U of A Space Institute.

Further Reading: U of A News

The post NASA is Building a Space Telescope to Observe Exoplanet Atmospheres appeared first on Universe Today.

After a vacation hiatus, Bill Maher is back with a monologue called, “New rules: political firestorm.”  Here he parses blame for the L.A. fires between unavoidable causes (no rain, lots of brush) and avoidable ones (blockheaded politicians).  The latter, he says, involves cuts in the firse-department budget, stolen or nonfunctional hydrants, empty reservoirs, exposed power lines, and a mayor who was off in Africa after saying she wouldn’t leave L.A. while in office.

Maher is clearly pissed off, more so than in many other videos. But he’s still funny (note his criticism for a city statement apparently prioritizing DEI over fighting fires.)

h/t: Divy

When I was invited to go on Piers Morgan Uncensored, I was deeply undecided.  I knew Morgan was quite conservative and religious, and I’ve seen clips of him bullying his guests.  So I had a back-and-forth with the producer, trying to discern what Morgan wanted to ask me about. I got a long list of questions, which I decided I could field, but it turned out that Morgan was on my side about the sex binary, the need to treat trans and non-binary gender people with respect and dignifty, but also for the need to discuss the issue of what happens when trans rights conflict with the rights of other groups, most especially women. Further it also turned out that the big issue for Morgan was trans women in women’s sports, something I could easily discuss.  Finally, I asked several of my friends who had been on that show, who encouraged me to go on.

So I said “yes”—with some trepidation. I emphasized that I didn’t want to debate, because I don’t see debates as a good way to rationally discuss issues (you can see a failed attempt below), and I prefer to express my views in talks or written articles, where rhetorical dexterity is not so important.  That was fine with the producer.  They gave me half an hour, and then said there would be a multi-person debate following my segment, though they didn’t tell me the participants.  They are listed below.  They sent a fancy studio truck to my University, complete with a Chicago background and a satellite broadcasting dish, and lo and behold, I was on t.v. (taped).

It turned out that yes, Piers and I agreed in our one-on-one, which goes for the first 25½ minutes below and involves mostly sports. My segment was followed by a heated debate.  Here’s the YouTube description:

This week, House Republicans passed a bill that bans transgender women and girls from school sports, and soon that legislation will advance to the Senate. Speaker Mike Johnson, says this move protects young girls, but others say this will further ostracise vulnerable kids. Emotions are running high, and people on both sides of the debate are reporting receiving online abuse and death threats.

To cover this vital discussion, Piers Morgan speaks to biologist Jerry Coyne, who left the Freedom from Religion Foundation due to its position on sex and gender. Then, he turns to his panel made up of host of ‘Tomi Lahren is Fearless’ Tomi Lahren, Executive Director from the progressive organisation, Rebellion Pac, Brianna Wu and trans rights activist, Eli Erlick for their expert opinions.

I had heard of Tomi Lahren and Brianna Wu before, but not Eli Erlick. (Wu and Erlick are trans women, while Lahren is a biological woman, but hates that term and prefers to call herself just “a woman.”)  But I knew little about any of them. It turns out that both Wu and Lahren agree that extreme trans activism was hurting the trans movement, while Erlick basically takes issue with everything I said.  Everybody save Erlick got quite exercised, and of course there was no rapprochement.

But one thing that came out, which is mentioned on Wikipedia, is that Erlick, at the least, had a plan to illegally supply puberty blockers to “trans children and adolescents”.  And at least one source says that Erlick actually followed through with this distribution, which is clearly unethical and possibly dangerous. (At 46:00, Erlick more or less admits she did indeed do the distribution.)

I think Wu would have had a bit more credibility had she not characterized Erlick and her confrères as “trans freak show friends”, and the same with Lahren and her “rainbow mafia” designation. (Wu is clearly disturbed that the excesses of gender activists could have helped Harris lose the election.)

Nevertheless, I do agree in general with what Wu and Lahren said.  Even conservatives (e.g., Lahren and Morgan) can be right about some things, and this is one of them.  Surely organizations like the ACLU or FFRF would not approve of the illegal distribution of puberty blockers to children!

Anyway, here’s the 50-minute video, which shows that, at least at present, there is no possibility of a thoughtful adjudication of the few areas in which trans rights clash with women’s rights.

Addendum: Although Erlick denies that the authors of study described below—mentioned by Lahren at 46:45—tried to bury it, Erlick is wrong.It has, as far as I know, still not been published.  Read the NYT article below by clicking the headline, or find it archived here:

An excerpt:

An influential doctor and advocate of adolescent gender treatments said she had not published a long-awaited study of puberty-blocking drugs because of the charged American political environment.

The doctor, Johanna Olson-Kennedy, began the study in 2015 as part of a broader, multimillion-dollar federal project on transgender youth. She and colleagues recruited 95 children from across the country and gave them puberty blockers, which stave off the permanent physical changes — like breasts or a deepening voice — that could exacerbate their gender distress, known as dysphoria.

The researchers followed the children for two years to see if the treatments improved their mental health. An older Dutch study had found that puberty blockers improved well-being, results that inspired clinics around the world to regularly prescribe the medications as part of what is now called gender-affirming care.

But the American trial did not find a similar trend, Dr. Olson-Kennedy said in a wide-ranging interview. Puberty blockers did not lead to mental health improvements, she said, most likely because the children were already doing well when the study began.

“They’re in really good shape when they come in, and they’re in really good shape after two years,” said Dr. Olson-Kennedy, who runs the country’s largest youth gender clinic at the Children’s Hospital of Los Angeles.

That conclusion seemed to contradict an earlier description of the group, in which Dr. Olson-Kennedy and her colleagues noted that one quarter of the adolescents were depressed or suicidal before treatment.

This is a prime example of scientific truth being kept under wraps because it undermines people’s ideology.

Interview with Nick Tiller, News Items: Does Fact-Checking Work, Nuclear Electric Propulsion, The LA Fires, Building Materials for Storing Carbon; Who's That Noisy; Science or Fiction

On Thursday, January 16th, at 02:03 AM EST, Blue Origin’s New Glenn rocket took off on its maiden flight from Launch Complex 36 at Cape Canaveral Space Force Station. This was a momentous event for the company, as the two-stage heavy-lift rocket has been in development for many years, features a partially reusable design, and is vital to Bezos’ plan of “building a road to space.” While the company failed to retrieve the first-stage booster during the flight test, the rocket made it to orbit and successfully deployed its payload -the Blue Ring Pathfinder – to orbit (which has since begun gathering data).

According to the most recent statement by Blue Origin, the second stage reached its final orbit following two successful burns of its two BE-3U engines. The successful launch of NG-1 means that Blue Origin can now launch payloads to Low Earth Orbit (LEO), a huge milestone for the commercial space company. “I’m incredibly proud New Glenn achieved orbit on its first attempt,” said Blue Origin CEO Dave Limp in a company statement. “We knew landing our booster, So You’re Telling Me There’s a Chance, on the first try was an ambitious goal. We’ll learn a lot from today and try again at our next launch this spring. Thank you to all of Team Blue for this incredible milestone.”  

The rocket is named in honor of NASA astronaut John Glenn, a member of the Mercury 7 and the first American astronaut to orbit Earth as part of the Liberty Bell 7 mission on July 21st, 1961. This is in keeping with Blue Origin’s history of naming their launch vehicles after famous astronauts, such as the New Shepard rocket. This single-stage suborbital launch vehicle is named in honor of Alan Shepard, the first American astronaut to go to space as part of the Freedom 7 mission on May 5th, 1961.

Unlike the New Shepard, a fully reusable vehicle used primarily for space tourism and technology demonstrations and experiments, the New Glenn has a reusable first stage designed to land at sea on a barge named Jacklyn, or Landing Platform Vessel 1 (LPV1). While the second stage is not currently reusable, Blue Origin has been working on a reusable second stage (through Project Jarvis) since 2021. While development began on the New Glenn in 2013, the rocket has been stuck in “development hell” since 2016, shortly after it was first announced.

As a result, Blue Origin began lagging behind its main competitor (SpaceX) and missed out on several billion dollars worth of contracts. This included the company’s failure to secure a National Security Space Launch (NSSL) procurement contract and the U.S. Space Force’s termination of their launch technology partnership in late 2020. In 2021, the ongoing delay led to Jeff Bezos announcing that he would step down as CEO of Amazon Web Services (AWS) to take the helm at Blue Origin. By February 2024, the first fully-developed New Glenn rocket was unveiled at Launch Complex 36.

This mission not only validated the launch vehicle that is vital to the company’s future plans in space. It also served as the first of several demonstrations required to be certified for use by the National Security Space Launch program. “The success of the NG-1 mission marks a new chapter for launch operations at the Eastern Range, redefining commercial-military collaboration to maintain SLD 45’s position as the world’s premier gateway to space,” wrote Airman 1st Class Collin Wesson of the U.S. Space Force (USSF) Space Launch Delta 45 (SLD 45) Public Affairs, shortly after the launch.

These plans include the launch of Amazon’s proposed constellation of internet satellites (Project Kuiper) and the creation of the Orbital Reef – a proposed commercial space station under development by Blue Origin and Sierra Space. They have also secured a contract with NASA to launch the Escape and Plasma Acceleration and Dynamics Explorers (ESCAPADE) mission, two satellites that will study how solar wind interacts with Mars’ magnetic environment and drives atmospheric escape. NASA has also contracted with Blue Origin to provide payload and crewed launch services for the Artemis Program.

Artist’s concept of the Blue Moon Mk. II lander. Credit: Blue Origin

This includes the cargo lander Blue Moon Mark 1 and the Mark 2 that will transport the Artemis V astronauts to the lunar surface. This flight and those that will follow place Blue Origin among other commercial space companies poised to break up the near-monopoly SpaceX has enjoyed for over a decade. Said Jarrett Jones, the Senior VP for Blue Origin’s New Glenn:

“Today marks a new era for Blue Origin and for commercial space. We’re focused on ramping our launch cadence and manufacturing rates. My heartfelt thanks to everyone at Blue Origin for the tremendous amount of work in making today’s success possible, and to our customers and the space community for their continuous support. We felt that immensely today.” 

Further Reading: Blue Origin

The post New Glenn Reaches Orbit, but Doesn't Recover the Booster appeared first on Universe Today.

Six or seven billion years ago, most stars formed in super star clusters. That type of star formation has largely died out now. Astronomers know of two of these SSCs in the modern Milky Way and one in the Large Magellanic Cloud (LMC), and all three of them are millions of years old.

New JWST observations have found another SSC forming in the LMC, and it’s only 100,000 years old. What can astronomers learn from it?

SSCs are responsible for a lot of star formation, but billions of years have passed since their heyday. Finding a young one in a galaxy so close to us is a boon for astronomers. It gives them an opportunity to wind back the clock and see how SSCs are born.

New research published in The Astrophysical Journal presents the new findings. It’s titled “JWST Mid-infrared Spectroscopy Resolves Gas, Dust, and Ice in Young Stellar Objects in the Large Magellanic Cloud.” The lead author is Omnarayani (Isha) Nayak from the Space Telescope Science Institute and NASA’s Goddard Space Flight Center.

At about 160,000 light-years away, the LMC is close in terms of galactic neighbours. It’s also face-on from our vantage point, making it easier to study. The N79 region in the LMC is a massive star-forming nebula about 1600 light-years across. The JWST used its Mid-Infrared Instrument (MIRI) and found 97 new young stellar objects (YSOs) in N79, where the newly discovered super star cluster, H72.97-69.39, is located.

This image from the NASA/ESA/CSA James Webb Space Telescope shows N79, a region of interstellar atomic hydrogen that is ionized and is captured here by Webb’s Mid-InfraRed Instrument (MIRI). N79 is a massive star-forming complex spanning roughly 1630 light-years in the generally unexplored southwest region of the LMC. At the longer wavelengths of light captured by MIRI, Webb’s view of N79 showcases the region’s glowing gas and dust. Star-forming regions such as this are of interest to astronomers because their chemical composition is similar to that of the gigantic star-forming regions observed when the Universe was only a few billion years old, and star formation was at its peak. Image Credit: ESA/Webb, NASA & CSA, M. Meixner CC BY 4.0 INT

Stellar metallicity increases over time as generations of stars are born and die. The LMC’s metallic abundance is only half that of our Solar System, meaning the conditions in the new SSC are similar to when stars formed billions of years ago in the early Universe. This is another of those situations in astronomy where studying a particular object or region is akin to looking into the past.

“Studying YSOs in the LMC gives astronomers a front-row seat to witness the birth of stars in a nearby galaxy. For the first time, we can observe individual low-mass protostars similar to the Sun forming in small clusters—outside of our own Milky Way Galaxy,” said Isha Nayak, lead author of this research. “We can see with unprecedented detail extragalactic star formation in an environment similar to how some of the first stars formed in the universe.”

The YSOs near the SSC H72.97-69.39 (hereafter referred to as H72) are segregated by mass. The most massive YSOs are concentrated near H72, while the less massive are on the outskirts of N79. The JWST revealed that what astronomers used to think were single massive young stars are actually clusters of YSOs. These observations confirm for the first time that what appear to be individual YSOs are often small clusters of protostars.

A composite image created using JWST NIRCam and ALMA data. Light from stars is shown in yellow, while blue and purple represent the dust and gas fueling star formation. Image Credit: NSF/AUI/NSF NRAO/S.Dagnello

This finding brings attention to the complex processes of early star formation. “The formation of massive stars plays a vital role in influencing the chemistry and structure of the interstellar medium (ISM),” the authors write in their published research. “Star formation takes place in clusters, with massive stars dominating the luminosity.”

One of the five young stars is over 500,000 times more luminous than the Sun. As revealed by the JWST Near InfraRed Camera (NIRCam), it’s surrounded by more than 1,550 young stars.

This Spitzer image from the new research shows the N79 region in the LMC. N79 consists of three giant molecular clouds. Spitzer data showed that each of the red circles is a massive young stellar object of at least eight solar masses. However, the JWST has revealed that three of them, with the exception of the one in N79W, aren’t individual YSOs; they’re clusters. Together, they could make up a very young super star cluster. Image Credit: Nayak et al. 2025.

Previous Atacama Large Millimeter/submillimeter Array (ALMA) observations hinted at what might contribute to the formation of SSCs. ALMA showed that colliding filaments of molecular gas at least one parsec long are in the region. These filaments could be behind H72’s formation.

This figure from previous research shows ALMA observations of the region near the super star cluster H72. Each one shows carbon monoxide in a different velocity channel. The white “x” shows the location of H72. “Scrolling through the channels it is clear there is a filament in the northeast to southwest direction and a distinct filament in the northwest to southeast direction,” the authors explain. Image Credit: Nayak et al. 2019.

This work highlights JWST’s power to resolve complex star formation locations in other galaxies. Not only did the JWST show us that what appeared to be individual YSOs are actually groups of stars, but it allowed the researchers to determine their mass accretion rates and chemical properties. The JWST’s new data gives astronomers new insights into complex chemistry, including the presence of organic molecules, dust, and ice in star-forming regions.

The post Astronomers are Watching a Newly Forming Super Star Cluster appeared first on Universe Today.

In the years following the launch of NASA's Hubble Space Telescope, astronomers have tallied over 1 trillion galaxies in the universe. But only one galaxy stands out as the most important nearby stellar island to our Milky Way -- the magnificent Andromeda galaxy (Messier 31). It can be seen with the naked eye on a very clear autumn night as a faint cigar-shaped object roughly the apparent angular diameter of our Moon. A century ago, Edwin Hubble first established that this so-called 'spiral nebula' was actually very far outside our own Milky Way galaxy -- at a distance of approximately 2.5 million light-years or roughly 25 Milky Way diameters.