Speaker 1: Welcome to Bedtime Astronomy. Explore the wonders of the cosmos
Speaker 1: with our soothing Bedtime Astronomie podcast. Each episode offers a
Speaker 1: gentle journey through the stars, planets, and beyond, perfect for
Speaker 1: unwinding after a long day. Let's travel through the mysteries
Speaker 1: of the universe as you drift off into a peaceful
Speaker 1: slumber under the night sky.
Speaker 2: Imagine for a moment that the universe is this massive,
Speaker 2: complex symphony, but we've only ever listened to it through
Speaker 2: a tiny, cheap am radio speaker. You get the melody maybe,
Speaker 2: but you're missing ninety nine percent of the instruments, the texture,
Speaker 2: the death. Now, imagine someone hands you this full high
Speaker 2: definition digital receiver and it's capable of isolating one hundred
Speaker 2: and two distinct frequency channels, most of which we've never
Speaker 2: even heard before.
Speaker 3: That is absolutely the right analogy.
Speaker 2: That's sudden explosion of information. That's the perspective shift we're
Speaker 2: diving into today. We are talking about NASA's monumental achievement
Speaker 2: with the SPHEREx telescope, which has just given us a
Speaker 2: completely new way of seeing the cosmos.
Speaker 3: It really is the sources we've pulled together all center
Speaker 3: on this massive milestone announced by NASA. And this isn't
Speaker 3: just some incremental improvement on existing views of the universe.
Speaker 3: This is a wholesale, systemic revolution in how we capture
Speaker 3: the entire sky. It forces us to redefine what an
Speaker 3: all sky map even means.
Speaker 2: Okay, let's unpack this. The big news is that SPHEREx
Speaker 2: and that stands for a spectro photometer for the history
Speaker 2: of the universe, epoch of realization and ICE's.
Speaker 4: Explorer, which is a mouthful.
Speaker 2: It is, but we absolutely have to explain why every
Speaker 2: part of that name is so critical. The news is
Speaker 2: that it has successfully completed its first full sky infrared map,
Speaker 2: and it did this by capturing the entire cosmos in
Speaker 2: an unprecedented one hundred and two distinct bands of infrared
Speaker 2: light exactly.
Speaker 3: So our mission today is to extract the most critical
Speaker 3: insights from this. I mean, it's an astronomical achievement in
Speaker 3: every sense of the word. We need to look at
Speaker 3: the tech, how they actually built a system capable of this,
Speaker 3: the mechanics of it, and then crucially, how this multi
Speaker 3: channel high resolution spectral atlas is specifically designed to answer
Speaker 3: some of the most fundamental lingering questions we have about
Speaker 3: the Universe's origin, its rapid early expansion, and well it's
Speaker 3: evolution over fourteen billion years.
Speaker 2: And I want to emphasize the value for you, the learner.
Speaker 2: This is not just an announcement of a pretty picture.
Speaker 2: This is NASA saying we have created one hundred and
Speaker 2: two completely unique data fields, one hundred and two separate
Speaker 2: maps of the entire cosmos, all at the same time.
Speaker 2: It's staggering, and each map is packed with information that
Speaker 2: was previously either too faint, too obscured, or was just
Speaker 2: hidden in a wavelength we weren't even monitoring. So this
Speaker 2: deep dive will reveal what those data streams are designed
Speaker 2: to tell us from the universe's absolute infancy, tracing those
Speaker 2: fundamental ripples from the moment of inflation, all the way
Speaker 2: to locating the molecular ingredients for life in our own
Speaker 2: Milky Way galaxy. It's a fantastic in depth shortcut to
Speaker 2: understanding one of the most powerful tools in modern astrophysics.
Speaker 3: Let's start with the core accomplishment, then the mapping of
Speaker 3: the entire sky in infrared light. It sounds simple when
Speaker 3: you say it like that, but the scope is just
Speaker 3: enormous and the choice of infrared is really the wnchpin
Speaker 3: of the whole mission.
Speaker 2: And crucially, this is energy the human eye can't detect.
Speaker 2: Infrared light. We often think of it as heat radiation,
Speaker 2: and it's absolutely everywhere in the cosmos revelent. Yeah, it's
Speaker 2: the light from cooler objects like dust and certain molecules,
Speaker 2: and it's also the light from the most distant objects
Speaker 2: stretched by the universe's expansion. If you're only looking invisible light,
Speaker 2: you're missing most of the action and you're often blocked
Speaker 2: completely by cosmic dust.
Speaker 3: The ability of infrared light to pierce through those dense,
Speaker 3: dusty nebulae is it's paramount here. Stars and planets are
Speaker 3: born in these huge clouds of gas and dust. They're
Speaker 3: like oh paque curtains. In the visible spectrum, you can't
Speaker 3: see a thing, not a thing. But in for red light,
Speaker 3: with its longer wavelengths, it just slips right through that curtain.
Speaker 3: It allows us to see the actual heat the molecular
Speaker 3: signatures of the stellar nurseries. Within SPHEERX isn't trying to
Speaker 3: find new visible light objects. It's trying to see the
Speaker 3: objects that are defined by their invisibility, and.
Speaker 2: The timeline for this mission's initial phase is just incredibly tight.
Speaker 3: It is so the sphex mission launched in March twenty
Speaker 3: twenty five and began systematic sky mapping by May, just
Speaker 3: a couple months barely, and by December eighteenth, twenty twenty five,
Speaker 3: so just about six months after the censors turned on,
Speaker 3: it completed its first all sky mosaic six months. In
Speaker 3: just half a year, it viewed space in every single direction,
Speaker 3: capturing three hundred and sixty degrees of the celestial sphere.
Speaker 2: A six month turnaround for a map of the entire universe,
Speaker 2: especially one with that much complex spectral data, that sounds
Speaker 2: almost impossibly fast. It makes me wonder how robust can
Speaker 2: a single six month scan really? Are we talking about
Speaker 2: high quality final data right out of the gate.
Speaker 3: That's a critical question, and the answer is that this
Speaker 3: first mosaic is really just the foundation. The sources confirm
Speaker 3: that Spherrex is designed as a marathon, a systematic survey
Speaker 3: that requires repetition. Its primary mission is set for two
Speaker 3: years two years, and during that time it will complete
Speaker 3: three additional all sky scans, so it's going to view
Speaker 3: the entire sky four times. Over two years.
Speaker 2: So it's not just one one oh two channel map,
Speaker 2: but four overlapping maps of the entire sky, all layered
Speaker 2: on top of each other. Why why is that layering necessary?
Speaker 2: What does that biome? Scientifically?
Speaker 3: Precisely merging those formaps together is fundamentally about increasing the
Speaker 3: signal to noise ratio. Okay, think of it like taking
Speaker 3: four long exposures with a camera instead of one short one.
Speaker 3: Each time SPHEREx scans a region, it collects more photons,
Speaker 3: more information. By co adding the data from all four passes,
Speaker 3: they can significantly increase the sensitivity of the measurements. It
Speaker 3: lets them detect fainter, more distant objects with much greater
Speaker 3: confidence and filter out you know, transient noise like cosmic
Speaker 3: rays hitting the detector.
Speaker 2: That systematic repetition for complete scans. Yeah, that must be
Speaker 2: absolutely essential for the mission's cosmological golds, especially when you're
Speaker 2: trying to marror these tiny, subtle differences in how galaxies
Speaker 2: are clustered billions of light years away.
Speaker 3: Absolutely, And here's a crucial detail that really aligns with
Speaker 3: the collaborative ethos of modern space science. What's that the
Speaker 3: entire data set, all four scans all the co added
Speaker 3: final maps, all the raw spectral information is being made
Speaker 3: freely available to scientists and to the public.
Speaker 2: Wow.
Speaker 3: This completely democratizes the discovery process globally. It ensures that
Speaker 3: every research institution, regardless of its size, can dig into
Speaker 3: the deepest mysteries of the universe.
Speaker 2: That public access feature seems critical. What's the precedent for
Speaker 2: releasing such a massive spectral data set so quickly? Is
Speaker 2: that typical for emission of this scale.
Speaker 3: It's becoming the gold standard, particularly for survey emissions like this.
Speaker 3: The sheer vastness of the data I mean, spanning one
Speaker 3: hundred and two unique channels across the entire sky, no
Speaker 3: single team could ever exploit its full scientific potential on
Speaker 3: their own.
Speaker 2: Just just too much.
Speaker 3: Exactly. By making it immediately public, NASA ensures that thousands
Speaker 3: of independent researchers, from planetary scientists to cosmologists, can apply
Speaker 3: their specific expertise to different subsets of the data, all
Speaker 3: at the same time. It just accelerates discovery exponentially.
Speaker 2: But let's go back to those one hundred and two
Speaker 2: spectral channels. For a non astrophysicist, it's still a bit abstract.
Speaker 2: I find it hard to picture what having one hundred
Speaker 2: and two specific measurements of invisible light actually means in practice.
Speaker 2: What information is being separated by these distinct wavelengths. Well,
Speaker 2: the number one of two is a technological and scientific
Speaker 2: sweet spot. It's a compromise between survey speed scanning the
Speaker 2: whole sky quickly, and spectral resolution getting enough detail to
Speaker 2: identify materials and measure distances. The source Maduig exists some
Speaker 2: really concrete examples. Okay, give us an example of this
Speaker 2: separation in action.
Speaker 3: All right, Consider a star forming region. In one set
Speaker 3: of say ten spectral channels. The emissions might be completely
Speaker 3: dominated by the light from hot, massive young stars. Okay,
Speaker 3: that data would show up as these bright energetic points,
Speaker 3: maybe looking blue or white if we assign them visible colors.
Speaker 3: But shift your focus just slightly to a different set
Speaker 3: of channels centered around say four to eight microns and
Speaker 3: the other red, and suddenly you see something completely different.
Speaker 2: You lose the stars and you gain the dust.
Speaker 3: Right precisely, you gain the thermal radiation that's emitted by
Speaker 3: the cosmic dust grains that have been heated up by
Speaker 3: those very stars. Cosmic dust, like you said, is critical
Speaker 3: for forming new stars and planets, but it's the ultimate
Speaker 3: obscure invisible light right. SPHERX captures this dust brilliantly because
Speaker 3: it radiates so strongly in specific infrared bands, and conversely,
Speaker 3: the source mentions that the same dust is totally invisible
Speaker 3: in others.
Speaker 2: So you have one map where a massive star forming
Speaker 2: nebula is a glowing beacon of heat, and then you
Speaker 2: have a complimentary map where that same nebula just disappears entirely,
Speaker 2: leaving only the background stars exactly. The scientific breakthrough isn't
Speaker 2: just the map itself, it's the comparison and synthesis of
Speaker 2: all one hundred and two of those maps.
Speaker 3: That's it. Each channel acts as a targeted filter. It's
Speaker 3: picking up the unique emission signatures, the fingerprints of specific atoms,
Speaker 3: or ions or cold molecules. Comparing the intensity across those
Speaker 3: one hundred and two channels, less astronomers figure out not
Speaker 3: only what is present like.
Speaker 2: Carbon monoxide, water, ice, hot.
Speaker 3: Hydrogen exactly, but also how distant it is and how
Speaker 3: much of it there is.
Speaker 2: This is where it gets really interesting, because this mission's
Speaker 2: unique ability to combine this massive scale with such a wide,
Speaker 2: rich spectrum earned it this fantastic memorable nickname.
Speaker 3: Ah yes, the comparison to the Ultimate Eye and the
Speaker 3: Animal Kingdom.
Speaker 2: Yes.
Speaker 3: Beth Favinsky, the sphere X project manager at JPL, she
Speaker 3: called it the Mantis Shrimp of telescopes.
Speaker 2: That is instantly memorable and it's such a high bar
Speaker 2: for those who don't know. The manta shrimp is famous
Speaker 2: for having one of the most complex visual systems in nature.
Speaker 2: It can see up to sixteen different types of photoreceptors.
Speaker 3: Compared to R three.
Speaker 2: Exactly. It sees channels for ultraviolet light, polarized light. Stuff
Speaker 2: that's way beyond what we can.
Speaker 3: Perceive, and the analogy holds up perfectly for spherx's function.
Speaker 3: The telescope's real power is that it combines this amazing
Speaker 3: multicolored detection system one hundred and two spectral channels with
Speaker 3: the ability to survey a massive, wide swath of its
Speaker 3: surroundings the entire sky, and.
Speaker 2: To do it over and over again quickly.
Speaker 3: That's the key. It's not just seeing many colors in
Speaker 3: one tiny spot like GWST does. It's seeing everything in
Speaker 3: one hundred and two colors every six months. It's the
Speaker 3: ultimate cosmic spectral survey machine.
Speaker 2: The mantis shrimp is a brilliant analogy for the result
Speaker 2: the richness of the data. But let's shift our deep
Speaker 2: dive into the engineering behind the How How does a
Speaker 2: telescope manage to generate one hundred and two separate spectral
Speaker 2: maps at the same time with this kind of speed
Speaker 2: in coverage?
Speaker 3: This brings us to the core scientific technique driving the mission. Spectroscopy.
Speaker 3: At its heart, spectroscopy is just the process of separating
Speaker 3: the light from a source into its.
Speaker 4: Component wavelengths, into its colors.
Speaker 3: Into its colors exactly. So when SPHEREx says it detects
Speaker 3: one hundred and two spectral bands, it means it is
Speaker 3: precisely measuring the intensity of light at one hundred and
Speaker 3: two specific, narrowly defined points all across the infrared spectrum.
Speaker 2: So it's not just painting a general infrared picture. It's
Speaker 2: quantitatively measuring the specific fingerprints of light emitted by different
Speaker 2: atoms and molecules out there. It's doing chemistry on a
Speaker 2: cosmic scale.
Speaker 3: That's precisely right. Every element, every common molecule, hydrogen, oxygen,
Speaker 3: carbon dioxide, and every physical process in the universe from
Speaker 3: the extremely hot glow of Equasar to the cold complex
Speaker 3: organic molecules hidden in dust clouds has a unique spectral signature.
Speaker 3: By sampling one hundred and two points across that spectrum,
Speaker 3: SPHEREx acquires a detail yet wide ranging picture of what's
Speaker 3: there and what state it's in.
Speaker 2: That still sounds like a massive technical challenge. How did
Speaker 2: the engineers manage to create a system that can look
Speaker 2: at the whole sky and filter it into one hundred
Speaker 2: and two separate data streams, all while staying cold enough
Speaker 2: to even function in the infrared.
Speaker 3: It is a technical marvel, and it required overcoming some
Speaker 3: significant thermal challenges. Since sphere x is looking for infrared light,
Speaker 3: which is essentially heat, the detectors themselves have to be
Speaker 3: kept incredibly cold, many degrees below zero, to prevent their
Speaker 3: own thermal radiation from drowning out the faint cosmic signal.
Speaker 4: Right, it would just be noise, total noise.
Speaker 3: But the real innovation is in the filtering mechanism.
Speaker 2: Let's detail that. How did they physically achieve one hundred and.
Speaker 3: Two channels so to get this massive color spectrum simultaneously
Speaker 3: across its wide field of view. The observatory uses six
Speaker 3: individual detectors, and here is the clever bit of optical engineering.
Speaker 3: Each of those six detectors is paired with a specially
Speaker 3: designed filter called a linear variable filter or LVF.
Speaker 2: Any or variable filter. Okay, explain that in concrete terms,
Speaker 2: what does a gradient filter look like.
Speaker 3: Picture a standard camera filter, which usually just blocks all
Speaker 3: light except for one specific color. Okay, The CRX filter
Speaker 3: is different. Imagine a narrow rectangle of glass where the
Speaker 3: color it transmits changes continuously along its length, kind of
Speaker 3: like a smooth rainbow or a gradient. At one end,
Speaker 3: it might only let through light at one micron, which
Speaker 3: is near infrared. Halfway down it might let through three microns,
Speaker 3: which is mid infrared, and at the far end five microns.
Speaker 2: Ah. So the filter's properties actually change depending on where
Speaker 2: the light hits it.
Speaker 3: Exactly as the light from the sky passes through the
Speaker 3: telescope and hits the detector, the light falling on different
Speaker 3: physical locations of that detector is simultaneously measuring a different wavelength.
Speaker 3: The light that hits the left side the detector is
Speaker 3: filtered differently than the light that hits the right side.
Speaker 3: This gradient allows each detector to simultaneously measure seventeen distinct
Speaker 3: colors or wavelength bands.
Speaker 2: That makes them add very clear but incredibly efficient detectors.
Speaker 2: Times seventeen distinct simultaneous spectral bands per detector gives you
Speaker 2: the grand total of one hundred and two.
Speaker 3: That's it.
Speaker 2: So every time SPHEREx takes a snapshot of a tiny
Speaker 2: patch of sky, it's actually generating one hundred and two
Speaker 2: separate measurements of spectral intensity for that one patch.
Speaker 3: Correct, every all sky map SPHEREx produces isn't just one file.
Speaker 3: It's one hundred and two separate, highly precise maps, each
Speaker 3: one telling a different, unique story about the structure and
Speaker 3: content of the universe at a different spectral depth. And
Speaker 3: this high sampling rate one hundred and two channels is
Speaker 3: what sets it so far apart from its predecessors, which
Speaker 3: might have used only three or four broad bands.
Speaker 2: Okay, now let's talk logistics. How does this system, this
Speaker 2: cosmic barcode scanner, manage to systematically cover the entire sky
Speaker 2: so quickly and precisely.
Speaker 3: It all relies on a very carefully maintained orbit and
Speaker 3: a systematic scanning pattern. SPHEREx is orbiting Earth in what's
Speaker 3: called a polar orbit. It travels from north to south
Speaker 3: passing over the poles about fourteen and a half times
Speaker 3: every day, and during those orbits, it points its gaze
Speaker 3: slightly away from the Earth in the sun, and it
Speaker 3: captures a specific narrow strip of the sky.
Speaker 2: So I'm picturing it essentially painting a long circular swath
Speaker 2: of the sky with every single orbit.
Speaker 3: That's a perfect way to put it. Each day it
Speaker 3: captures about three allows and six hundred individual images along
Speaker 3: one of these circular strips. But here's the key to
Speaker 3: getting full coverage. Because the Earth is also moving around
Speaker 3: the Sun, the telescope's line of sight gradually shifts relative
Speaker 3: to the distant stars. The strip of sky at views
Speaker 3: on day one is slightly different from the strip it
Speaker 3: views on day ten or day ninety.
Speaker 2: That gradual systematic shift must eventually guarantee a full sweep.
Speaker 3: It does after six months of continuous systematic scanning along
Speaker 3: these slightly shifting strips. This gradual progression allows the observatory
Speaker 3: to view space in every direction. It captures the entire
Speaker 3: three hundred and sixty degrees of.
Speaker 4: The sky, and then it just starts over, and then as.
Speaker 3: The orbital geometry repeats itself, it starts over again. For
Speaker 3: the second stand ensuring they collect those or repeated exposures.
Speaker 2: We talked about that repetitive systematic coverage is what guarantees
Speaker 2: that sensitivity boost. But let's talk about the real revolutionary leap.
Speaker 2: This detailed spectral data enables the jump from a two
Speaker 2: dimensional map of the cosmos to a complete three D atlas.
Speaker 3: This is perhaps the most critical scientific application of those
Speaker 3: one hundred and two spectral bands. Other powerful observatories have
Speaker 3: been mapping the positions of galaxies for years, but generally
Speaker 3: those maps are two dimensional. We know where they are
Speaker 3: in the sky they're celestial coordinates, but we don't know
Speaker 3: precisely how far away they are. They're just flattened onto
Speaker 3: a sphere.
Speaker 2: So if I see two galaxies that look like they're
Speaker 2: right next to each other on the map, I have
Speaker 2: no idea if they are actually cosmic neighbors, or if
Speaker 2: one is ten billion light years behind the other just
Speaker 2: lined up by chance in our.
Speaker 3: Field of view Exactly That missing depth is the distance component,
Speaker 3: and SPHEREx is one O two channel multi wavelength view
Speaker 3: provides the solution through what's called cosmological red shift.
Speaker 2: Okay, let's elaborate on this because This is where the
Speaker 2: precision of those hundred two channels really proves its value.
Speaker 2: How does measuring one hundred and two points across the
Speaker 2: infrared spectrum give them the distance?
Speaker 3: Well, when a galaxy emits light, that light has specific
Speaker 3: recognizable spectral features, emission lines and absorption lines created by
Speaker 3: the elements within it.
Speaker 2: Okay, like a fingerprint, perfect.
Speaker 3: Fingerprint, But because the universe is expanding, the farther away
Speaker 3: a galaxy is, the faster it appears to be moving
Speaker 3: away from us. This rapid motion stretches the light waves,
Speaker 3: shifting those recognizable spectral features towards the red or infrared
Speaker 3: end of the spectrum. This is redshift.
Speaker 2: So the farther away the galaxy, the more the light
Speaker 2: is stretched, and the deeper into the infrared, SPHEREx will
Speaker 2: see those fingerprint features precisely.
Speaker 3: Now. The older, simpler infrared surveys like ys used only
Speaker 3: four broad channels. That's enough to guess the red shift,
Speaker 3: but it's often prone to errors, especially when you're trying
Speaker 3: to pin down the distance to hundreds of millions of objects.
Speaker 2: So it is more of an estimate, a very rough one.
Speaker 3: Yes, SPHEREx by measuring one hundred and two specific points
Speaker 3: allows astronomers to do much more accurate spectral curve fitting.
Speaker 3: They can map the precise shape of the spectral curve
Speaker 3: of that galaxy's light.
Speaker 2: That ability to measure the curve with high resolution the
Speaker 2: one hundred and two photometric bands must allow them to
Speaker 2: pin down the distance with far greater certainty than before
Speaker 2: it does.
Speaker 3: They can identify specific spectral breaks and molecular features and
Speaker 3: then measure exactly how far they've been redshifted. This allows
Speaker 3: them to determine the distance to hundreds of millions of galaxies.
Speaker 3: Converting that two D celestial map into a full three
Speaker 3: D map of the universe, it provides accurate depth and volume,
Speaker 3: and that three D distribution how galaxies are clustered and
Speaker 3: distributed across billions of cubic light years that holds the
Speaker 3: key to unlocking the deepest mysteries of the universe's past.
Speaker 2: That transition to the high fidelity three D map really
Speaker 2: sets the stage for the enormous scientific goals of this mission.
Speaker 2: When you look at the name again spectrophotometer for the
Speaker 2: history of the Universe, epoch of realization and ices explore,
Speaker 2: it's clear this telescope is targeting cosmic history across the
Speaker 2: entire age of the cosmos. So let's tackle the most
Speaker 2: dramatic one first.
Speaker 3: We have to start with the most distant and complex target,
Speaker 3: which is literally at the very very beginning of time goal.
Speaker 2: Number one, gaining insights into the epoch of cosmic inflation.
Speaker 3: This is the cosmological reason they need that three D
Speaker 3: map of hundreds of millions of galaxies. Inflation is a
Speaker 3: theory describing an extraordinarily rapid and massive expansion of the
Speaker 3: universe in the earliest moments of existence.
Speaker 2: And the timing is just mind bendingly short.
Speaker 3: It's almost incomprehensible. The sources detail the timing of this event.
Speaker 3: It occurred in the first billionth of a trillion of
Speaker 3: a trillionth of a second after the.
Speaker 2: Big Bang, a fraction of a fraction of a fraction
Speaker 2: of a second, and yet it determined everything we see today.
Speaker 3: During that infinitesimally brief moment, the universe expanded by a
Speaker 3: factor of a trillion trillion fold. This dramatic burst solved
Speaker 3: several long standing cosmological puzzles, but the evidence for it
Speaker 3: is incredibly difficult to find because it happened so quickly
Speaker 3: and so early.
Speaker 2: So if this event was so fast and happened so
Speaker 2: long ago, how can it tell usco Blanch in twenty
Speaker 2: twenty five possibly find the evidence for it billions of
Speaker 2: years later. What's the link between Spherx's three D map
Speaker 2: and that moment of inflation?
Speaker 3: The link is quantum mechanics and gravity. According to inflation theory,
Speaker 3: the universe was not perfectly uniform before, during, or after
Speaker 3: that rapid expansion. The quantum fluctuations, these tiny random variations
Speaker 3: and energy density that existed at the subatomic level, they
Speaker 3: were stretched out to cosmic scales during that trillion trillionfold expansion.
Speaker 2: So the tiny random jitters that are inherent in quantum
Speaker 2: mechanics became massive, observable ripples across the structure of the
Speaker 2: brand new universe.
Speaker 3: Precisely, these initial microscopic variations and density were stretched out,
Speaker 3: and they became the seeds for all the large scale
Speaker 3: structure we observed today. Over the next fourteen billion years,
Speaker 3: gravity acted on these slight denser regions, causing them to
Speaker 3: collapse and form the massive clusters and superclusters of galaxies
Speaker 3: were now mapping.
Speaker 2: So the current three D distribution of galaxies like a
Speaker 2: fossil field of those initial quantum ripples.
Speaker 3: That's the perfect term for it.
Speaker 2: Ah, I see the connection. Now. By creating a precise
Speaker 2: three D map of how those hundreds of millions of
Speaker 2: galaxies are distributed in clustered today, scientists can effectively reverse
Speaker 2: engineer the size and shape of those initial density ripples
Speaker 2: that were set during inflation. They're looking for subtle statistical
Speaker 2: patterns in the galaxy distribution.
Speaker 3: Exactly, the subtle variations in galaxy clustering today are the
Speaker 3: imprint of that brief explosive moment. Sphere X is looking
Speaker 3: for two specific signatures, evidence of something called non gaussianity,
Speaker 3: meaning the distribution of the ripples wasn't perfectly random. Includes
Speaker 3: about the physics of the energy field that actually powered inflation.
Speaker 3: Measuring these variations with the precision afforded by a three
Speaker 3: D map of this size is one of the mission's
Speaker 3: absolute highest priority goals. It's trying to help us understand
Speaker 3: the specific physics of how the universe began.
Speaker 2: That is truly tackling the biggest possible question. Okay, let's
Speaker 2: fast forward from that microsecond event to goal number two,
Speaker 2: tracing the intermediate history of the cosmos, specifically galaxy evolution
Speaker 2: over fourteen billion years.
Speaker 3: This goal leverages the full spectral depth of the one
Speaker 3: hundred and two channels to understand how galaxies have lived
Speaker 3: and died across the universe's history. Galaxies aren't static elers.
Speaker 3: They're dynamic, chaotic systems that are constantly merging, consuming gas,
Speaker 3: generating new stars, or shutting down their star formation process entirely.
Speaker 2: And the one hundred and two spectral maps allow scientists
Speaker 2: to trace this history in a way that the handful
Speaker 2: of colors available to older instruments simply.
Speaker 3: Couldn't yes because different spectral channels are sensitive to different
Speaker 3: cosmic phenomena. For example, some channels are dominated by the
Speaker 3: light of young, hot massive stars. Other channels might be
Speaker 3: more sensitive to the older, redder stellar populations. By measuring
Speaker 3: the relative intensity across all one hundred and two bands,
Speaker 3: astronomers can accurately reconstruct the star formation history of a
Speaker 3: galaxy at any point in time.
Speaker 2: So they can look at a distant galaxy, measure it's
Speaker 2: one hundred and two spectral fingerprints and determine not only
Speaker 2: its distance, but also whether it's currently a starburst galaxy.
Speaker 2: Furiously generating new stars or a quenched galaxy that's run
Speaker 2: out of gas and is basically dormant.
Speaker 3: That's the key power. They can trace phenomena like metallicity,
Speaker 3: the amount of heavy elements present, which is an indicator
Speaker 3: of how many generations of stars have already lived and
Speaker 3: died within that galaxy. The one hundred and two bands
Speaker 3: allowed them to build a complete, time sequenced inventory of
Speaker 3: how galactic structures have.
Speaker 2: Evolved, distinguishing between changes caused by say, just running out
Speaker 2: of gas versus changes from violent galactic mergers.
Speaker 3: Right, this provides the context for everything we see locally,
Speaker 3: including our own Milky Way.
Speaker 2: That's a staggering amount of data focused on the distant
Speaker 2: past and present. But let's bring the focus much closer
Speaker 2: home for goal number three, the ingredients for life.
Speaker 3: This is where the ice is Explorer part of the
Speaker 3: SPHEREx acronym comes into play. It's focusing on the chemical
Speaker 3: precursors for life, which are distributed across the dense, cold
Speaker 3: molecular clouds of our own Milky Way galaxy.
Speaker 2: So we move from mapping the distribution of hundreds of
Speaker 2: millions of galaxies across fourteen billion years of history right
Speaker 2: back to the dense dust clouds in our own arm
Speaker 2: of the spiral. That's a massive shift in scale.
Speaker 3: It is, but it uses the exact same technology spectroscopy,
Speaker 3: just applied to different objects. This goal ties directly back
Speaker 3: to what we were saying earlier about specific infrared wavelengths
Speaker 3: penetrating dust. The source material stress that these dense clouds
Speaker 3: of dust where stars and planets form, radiate brightly in
Speaker 3: very specific infrared wavelengths.
Speaker 2: Right if you look at those dust clouds in visible light,
Speaker 2: they're just black silhouettes. They block all the light from behind.
Speaker 2: They're cold and dark, correct, But.
Speaker 3: If you look at them in spherx's specific infrared channels,
Speaker 3: you're seeing the thermal heat signature of the dust itself
Speaker 3: and the unique spectral fingerprints of the malicles the ice
Speaker 3: is contained within those clouds. When atoms bond together to
Speaker 3: form molecules like water or carbon dioxide, they vibrate at
Speaker 3: unique frequencies.
Speaker 2: And those unique frequencies fall into the infrared spectrum precisely.
Speaker 3: The one hundred and two channels are strategically positioned to
Speaker 3: detect the vibrational and rotational wobbles of these crucial molecules,
Speaker 3: especially those that are frozen onto the surface of dust
Speaker 3: grains in the cold, dark recesses of molecular clouds. They're
Speaker 3: specifically targeting things like water, ice, solid carbon monoxide, carbon dioxide,
Speaker 3: and methane, alongside more complex organic molecules.
Speaker 2: Why is mapping in the distribution of these specific ice.
Speaker 3: Is so vital because these are the chemical precursors that
Speaker 3: eventually coalesce into the protoplanetary discs, comets, and asteroids that
Speaker 3: seed new solar systems. Understanding the abundance and precise distribution
Speaker 3: of water ice, for example, tells us a great deal
Speaker 3: about the environment in which planets are born. If a
Speaker 3: region of the galaxy is rich in water and organic molecules,
Speaker 3: it's arguably a much better nurse for potentially habitable planetary systems.
Speaker 2: So by mapping the distribution and composition of these ingredients
Speaker 2: for life throughout the Milky Way, Spheerrex helps us understand
Speaker 2: not just if life is possible elsewhere, but where the
Speaker 2: best nurseries are located and what feedstock those new planetary
Speaker 2: systems had to start with. It's connecting the cosmological history
Speaker 2: to the biological possibility, all using the same hundred and
Speaker 2: two spectral keys.
Speaker 3: To truly appreciate the necessity and the scale of spherrex's achievement,
Speaker 3: we really need to place it in context alongside other
Speaker 3: major missions, both historical and cutting edge. SPHERX didn't invent
Speaker 3: infrared's die mapping, after all, but it absolutely took the
Speaker 3: technique to an entirely new level.
Speaker 2: So let's start with the history. How does spherx stack
Speaker 2: up against its infrared predecessors.
Speaker 3: We can look at previous all sky surveys, most notably
Speaker 3: NASA's Wide Field Infrared Survey Explorer or WHYSE. WHISE was
Speaker 3: a hugely successful mission that also mapped the entire sky
Speaker 3: and infrared light. It performed a crucial census of the
Speaker 3: local and distant universe.
Speaker 2: The worded whys fall short. What was the thing that
Speaker 2: necessitated SPHEREx.
Speaker 3: The key differentiator, as the source material makes very clear,
Speaker 3: is the spectral depth. The number of channels. WYSE used
Speaker 3: only four broad spectral bands, only four four. Imagine listening
Speaker 3: to that one oh two piece symphony through only four speakers.
Speaker 3: You get the volume, sure, but you lose all the
Speaker 3: detail you need to distinguish a tuba from a trombone,
Speaker 3: or in space terms, a dusty galaxy from a distant quasar. Spherrex,
Speaker 3: with its one hundred and two phonometric bands provides far,
Speaker 3: far greater precision.
Speaker 2: So wise was the initial low resolution sketch maybe in
Speaker 2: four colors, and SPHEREx is the final high definition spectral
Speaker 2: at LISS with one hundred and two distinct shades.
Speaker 3: Exactly the sheer volume of spectral data. The detail provided
Speaker 3: by those one hundred and two different measurement points is
Speaker 3: what transforms the map from a broad sensus into a
Speaker 3: precise diagnostic tool. As we discussed, that detail is necessary
Speaker 3: for accurate redshift measurement, which is the whole foundation of
Speaker 3: the three D map. The precision of the hundred and
Speaker 3: two channels minimizes the ambiguity that plague distance measurements derived
Speaker 3: from only four broadbands.
Speaker 2: Okay, now, let's move to the other end of the
Speaker 2: spectrum and compare SPHEREx to the current rock star of astrophysics,
Speaker 2: the James Web Space Telescope JWST. Right. JWST is legendary
Speaker 2: for its infrared capabilities and depth. If JWST is so powerful,
Speaker 2: why did NATHA decide the single biggest priority was another
Speaker 2: all sky survey like SPHEREx.
Speaker 3: That's a fantastic critical question, and the answer lies in
Speaker 3: their fundamentally complementary design philosophies. The sources provide a very
Speaker 3: clear distinction. DATAWST can perform spectroscopy with significantly more wavelengths
Speaker 3: of light than SPHEREx and has a much higher.
Speaker 4: Spectral resolution, so more detail, much more.
Speaker 3: Where SPHEREx measures one hundred and two distinct points, JWST
Speaker 3: might measure thousands of points across a narrower spectral range.
Speaker 3: It allows for incredibly fine identification of molecules and precise velocities.
Speaker 2: So JWST is the equivalent of a forensic lab microscope,
Speaker 2: capable of identifying every single trace element in a sample precisely.
Speaker 3: But the trade off is its field of view. The
Speaker 3: field of view for JAWST is thousands of times smaller
Speaker 3: than sphere x's. JAWST is designed to peer at one
Speaker 3: incredibly small, faint target for dozens, even hundreds of hours
Speaker 3: to gather maximum detail. It is the deep focus magnifying glass.
Speaker 3: If JWST were to try to map the entire sky,
Speaker 3: it would take centuries.
Speaker 2: Which makes SPHERX the necessary ultra wide angle survey camera.
Speaker 2: It may not get the forensic detail of JWST, but
Speaker 2: its unique power comes from that combination of seeing one
Speaker 2: hundred and two spectral channels and having a massive field
Speaker 2: of view that covers the entire sky, and doing it
Speaker 2: four times over.
Speaker 3: That combination is what allows the cosmological survey, the three
Speaker 3: D mapping of hundreds of millions of galaxies. That's something
Speaker 3: JWST simply couldn't achieve due to its narrow focus and
Speaker 3: time constraints. SPHEREx provides the universal context. It finds the
Speaker 3: millions of needles in the cosmic hay stack that are
Speaker 3: worthy of follow up.
Speaker 2: So it's a spotterer.
Speaker 3: It's the ultimate spotterer. It provides the initial distance and
Speaker 3: classificification for targets that JWST or ground based observatories can
Speaker 3: then be guided to for deeper, higher resolution inspection. They
Speaker 3: are a scientific tag team.
Speaker 2: That synergy and complementary role are vital for the mission's
Speaker 2: broader impact. It's something NASA officials were quick to stress,
Speaker 2: acknowledging that no single telescope can solve all of astrophysics questions.
Speaker 3: Yeah. Shawn Domigol Goldman, the director of the Astrophysics Division
Speaker 3: at NASA Headquarters noted that the information will be especially
Speaker 3: valuable when used alongside our other missions data to better
Speaker 3: understand our universe. This is the definition of multimission synergy.
Speaker 3: The whole is greater than the sum of its parts.
Speaker 2: He also perfectly captured the scale of the data delivery
Speaker 2: when he emphasized, and I'm quoting here, we essentially have
Speaker 2: one hundred and two new maps of the entire sky,
Speaker 2: each one in at a different wavelength and containing unique
Speaker 2: information about the objects it sees.
Speaker 3: That just highlights that this is not one discovery, but
Speaker 3: one hundred and two simultaneous data atlases being handed to
Speaker 3: the global scientific community exactly. And the expectation is that
Speaker 3: this treasure trove of public data will benefit everyone well
Speaker 3: beyond the initial mission goals. He expressed confidence that every
Speaker 3: astronomer is going to find something of value here, helping
Speaker 3: the world answer fundamental questions about the universe's start and
Speaker 3: the eventual creation of a home for us.
Speaker 2: It's a massive public data release. It means that the
Speaker 2: mission's primary goals inflation, galaxy evolution, ices that's only going
Speaker 2: to be the beginning of the discovery's sphere x.
Speaker 3: Enables right, which really underscores the point made by JPL
Speaker 3: director Dave Gallagher. He highlighted the mission as a phenomenal
Speaker 3: example of a mid sized astrophysics mission delivering big science.
Speaker 2: It's proof that powerful focused survey missions, when they're designed cleverly,
Speaker 2: like combining under and two high resolution spectral channels with
Speaker 2: systematic full sky coverage, can unlock enormous potential for discovery
Speaker 2: and accelerate our understanding faster than just relying on a
Speaker 2: single mega telescope alone.
Speaker 3: The man to shrimp, it turns out, is the essential
Speaker 3: key to unlocking the universal spectral Atlas.
Speaker 2: And what's interesting is how this blend of speed and
Speaker 2: spectral resolution addresses these fundamental unknowns. It's giving as context
Speaker 2: for the entire structure of the universe, and it's simultaneously
Speaker 2: informing cosmology and planetary science. The three D map links
Speaker 2: the earliest moments of existence with the very molecules that
Speaker 2: might form life right here in our backyard. It's a
Speaker 2: truly comprehensive scope.
Speaker 3: Well. The ability to cross reference data points is unparalleled.
Speaker 3: Imagine identifying a dense cloud of carbon dioxide ice in
Speaker 3: the Milky Way, knowing its precise spectral signature from one
Speaker 3: set of SPHEREx channels. Okay, then you use another set
Speaker 3: of Spherrex channels to calculate the distance and the environment
Speaker 3: of a very distant galaxy, and you identify a similar
Speaker 3: chemical process occurring billions of years ago. Spherx bridges these
Speaker 3: vast differences in time and space with its systematic spectral coverage.
Speaker 2: The fact that they are collecting one hundred and two
Speaker 2: data points for every single object that's moves this from
Speaker 2: a survey to a catalog of spectroscopic fingerprints. Every major
Speaker 2: cosmic structure now has a chemical and distance profile that
Speaker 2: is publicly available.
Speaker 3: And that access is transformative. It means that small universities
Speaker 3: or even highly motivated citizen scientists with powerful computing capabilities
Speaker 3: can contribute meaningfully to core cosmological research. The barrier to
Speaker 3: entry for analyzing the universe's large scale structure has been
Speaker 3: lowered significantly.
Speaker 2: The precision they must maintain to complete those four systematic
Speaker 2: scans over two years is also just mind boggling. They
Speaker 2: have to ensure that when they layer that fourth scan
Speaker 2: onto the first, they are aligned perfectly down to the
Speaker 2: pixel to maximize that sensitivity gain.
Speaker 3: Oh. Absolutely. That requires continuous precise monitoring of the spacecraft's
Speaker 3: orientation and highly stable operational temperatures for the detectors. Any
Speaker 3: fluctuation in temperature could throw off the infrared measurements, rendering
Speaker 3: the spectral data inaccurate. The engineering feed that's supporting the
Speaker 3: science is immense.
Speaker 2: So what does this all mean? Then, let's summarize the
Speaker 2: core contribution of SPHERX. It's providing one hundred and two
Speaker 2: detailed spectral maps one hundred and two different windows into
Speaker 2: invisible light of the entire sky, and it repeats this
Speaker 2: four times in two years, boosting its sensitivity.
Speaker 3: This multi channel spectral data enables the first truly comprehensive,
Speaker 3: high fidelity three D map of hundreds of millions of galaxies.
Speaker 3: It's moving us beyond the two D position maps and
Speaker 3: the simple estimates of distance we've primarily relied on.
Speaker 2: And this data is purpose built to tackle the biggest
Speaker 2: mysteries in the history of the universe. From tracing the
Speaker 2: subtle statistical patterns that fossil field left by the rapid
Speaker 2: expansion of cosmic inflation the very first fraction.
Speaker 3: Of a second, all the way to the continuous evolution
Speaker 3: of galaxies over fourteen billion years.
Speaker 2: Down to precisely mapping the dust clouds and ices that
Speaker 2: form stars and planets in our own Milky Way.
Speaker 3: So you now have the context for why this particular mission,
Speaker 3: with its specific combination of a y field of view
Speaker 3: and one hundred and two specific spectral channels is so
Speaker 3: essential for piecing together the universe's full history. It fills
Speaker 3: that crucial gap between broad, low resolution surveys and extremely
Speaker 3: high resolution, narrow focused deep field studies. It really is
Speaker 3: the crucial middle layer of modern astrophysics.
Speaker 2: But the truly provocative thought the thing for you to
Speaker 2: maul over. It comes back to the public availability of
Speaker 2: this data. If the universe's history is encoded in these
Speaker 2: under and two infrared maps, and if astronomers are using
Speaker 2: the three D plustering data to figure out what happened
Speaker 2: during inflation, imagine this. The entire data set is freely
Speaker 2: available to the public, ready for analysis. If you, the
Speaker 2: curious learner, had access to this incredible three D at
Speaker 2: LISS focused on those one hundred and two spectral bands,
Speaker 2: what specific structure or pattern would you look for first?
Speaker 3: And think about that manta shrimp analogy one final time.
Speaker 3: Even with one hundred and two spectral channels, we are
Speaker 3: only sampling the continuous infrared spectrum. There are still structures, processes,
Speaker 3: or even entirely new malag kills out there that may
Speaker 3: emit their unique fingerprint between the bands that spherx is measuring,
Speaker 3: perhaps existing at wavelengths we simply weren't looking for. What
Speaker 3: key cosmic information are we still blind to even with
Speaker 3: the most colorful, high volume cosmic map ever created. That's
Speaker 3: the challenge that remains, even with this phenomenal achievement now
Speaker 3: in the public domains at