Roman Launches: A Telescope's Countdown Ends

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Anna: Hey, everyone. Welcome back to Astronomy

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daily. It's Monday, August 31st,

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series five, episode 181.

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Avery: And, um, this is the good kind of Monday,

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Anna, because we finally get to talk about a

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launch that actually happened.

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Anna: Finally, after a full week of. It's coming,

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it's coming. Roman is up.

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Avery: The Nancy Grace Roman Space Telescope

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launched yesterday morning, right on time.

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And it went about as clean as a launch can

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go. We'll walk through the whole thing.

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Anna: Then SpaceX drops a pretty big hint

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about Falcon 9's eventual retirement.

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Two Nobel laureates weigh in on whether the

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universe's expansion is actually still

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speeding up. One very old

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asteroid strike explains two separate

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mysteries on a tiny Martian moon.

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And we'll get you sorted for what's actually

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worth looking up at tonight, wherever you

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are.

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Avery: Lots to get through, let's go.

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Anna: But start with the, uh, Nancy Grace Roman

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Space Telescope launch then.

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Avery: Okay. I've been waiting all week to say this.

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Tell me it went well.

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Anna: It went about as well as a launch

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possibly can. Liftoff was

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7:26 yesterday morning, Eastern Time.

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That's Sunday, August 30th, right on the

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primary window. No scrubs, no holds.

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SpaceX's Falcon Heavy took the Nancy Grace

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Roman Space Telescope up From Launch Complex

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39A at Kennedy Space Centre.

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Avery: The same pad Apollo flew from.

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Anna: The very same. And More recently, Artemis

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1 side boosters peeled away about 2

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1/2 minutes in and flew themselves home to

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landing zones at Cape Canaveral. Textbook

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boost back and landing on both. Main

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engine cutoff on the core stage came around

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the four minute mark and, um, Roman itself

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deployed clean 31 minutes after

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liftoff. No anomalies reported at any

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stage of the flight. By NASA's own account,

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about as tidy a run as you could hope for.

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Avery: I love it when they get to actually say that.

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Anna: There was a nice moment in the post launch

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press conference too. President Trump called

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in live to congratulate the team, which made

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for a slightly surreal watch alongside all

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the mission control.

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Avery: CHEERING okay, it's up, it's safely away from

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the rocket. What's next for it? And, um,

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remind everyone what it's actually for,

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because we've built this thing up all week

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without it existing in orbit.

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Anna: Yet right now it's real.

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Romans on a 90 day cruise out to the

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sun. Earth L2 point, about a

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million and a half kilometres from Earth,

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same neighbourhood as Webb. The first 40 days

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or so are instrument activation and status

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cheques. Then science commissioning kicks in

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from around day 45. First images

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are expected in early 2027.

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Avery: And there's an actual local link to this one

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too, isn't there? Not just an American

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storey.

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Anna: There is, and it's worth saying out loud,

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part of Roman's data is going to come down

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through a brand new ESA antenna in

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New Norcia in Western Australia.

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Roman's a formal ESA partnership, so

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that antenna's already built into how this

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mission gets its data home.

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Avery: I like that a lot. Okay. Remind people why

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this telescope is such a big deal. Because

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similar mirror size to Hubble undersells it

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badly.

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Anna: It does. Same 2.4 metre

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primary mirror as Hubble. But Roman's wide

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Field instrument gives it a view roughly a

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hundred times wider at basically the same

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sharpness. Where Hubble gives you a postage

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stamp, Roman gives you a poster.

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Programme scientist Dominic Benford put it

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nicely before launch. The smallest Roman

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images will be a billion pixels.

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There isn't a screen on Earth big enough to

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display all of them at once.

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Avery: Billion pixels in the smallest image.

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Anna: The smallest. And that scale is

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entirely the point. The flagship project is

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the High Latitude Wide area survey.

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Roughly 2 billion galaxies imaged to

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map dark matter and chart how dark energy

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is pulling the universe apart faster over

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time. There's a companion supernova time

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domain survey chasing the same question from

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a different angle. And funnily enough, that's

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relevant to our next storey today too.

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Avery: And um, the exoplanet hunt, that's the one I

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always want.

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Anna: More detail on the galactic bulge. Time

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domain survey, a completely different

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technique to Kepler or tess. It watches for

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a foreground star's gravity, briefly

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magnifying light from something behind it.

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With a planet adding its own little blip to

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that signal, it catches things. Transit

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surveys can't wide orbit planets. Even

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free floating rogue planets with no star at

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all bear expecting on the order of

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100,000 new detections from that

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survey alone.

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Avery: 100,000 new worlds from one survey.

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Anna: From one survey. And there's a fourth

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instrument riding along the coronagraph, a

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technology demonstration for directly imaging

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exoplanets by blocking out the glare of their

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host star rather than just inferring they're

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there. If it works as hoped, it's a real

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stepping stone toward NASA's future flagship

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missions. Doing that a, uh, standard.

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Avery: So walk me back through the week because this

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has actually been a four part storey and I

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don't think we've said that out loud yet.

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Anna: It has. Tuesday we told you. Roman

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got cleared for launch nine months ahead of

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schedule, which is almost unheard of for a

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NASA flagship mission. Thursday we told the

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genuinely Strange storey of how its core

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optics started life inside a, uh,

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cancelled National Reconnaissance Office

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spy satellite programme before being

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donated to NASA back in 2012.

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Friday we told you it survived a budget

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draught that would have cancelled it

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outright, and how the team that saved it

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responded by pulling the launch forward eight

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months instead of slipping it. And Saturday

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we previewed the launch itself.

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Avery: And today the actual thing happened.

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Anna: The actual thing happened. Clean launch,

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clean deployment, on its way to L2.

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First images due early next year. After

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everything that had to go right just to get

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it off the ground, it's genuinely satisfying

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to get to close the loop on this one.

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Avery: A very good Monday indeed.

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Next up, sticking with SpaceX for a second

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because Elon Musk said something last week we

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haven't gotten to yet worth flagging.

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Anna: Even though the post itself isn't brand new.

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Musk said on X on August 22

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that winding down both Falcon 9 and

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Falcon Heavy is, in his words,

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inevitable.

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Avery: Inevitable. That's a strong word for the

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rocket that's basically been SpaceX's entire

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business for a decade.

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Anna: It is, but the condition he attached

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matters. Once Starship is flying

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reliably several times a week, he says it

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makes sense to shift production resources

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over to Starship and push its launch rate

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up to multiple times a day.

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Avery: So this isn't, um, we're retiring Falcon 9

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next quarter?

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Anna: Not remotely. It's a statement of intent,

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not a timeline. Falcon 9 only just hit

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its 100th launch of the year back on August

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25th, and Booster

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B1067 set a new

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single booster reuse record at 37

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flights on that very mission. This is still

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an enormously active fleet.

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Avery: So what's the actual estimate for when this

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starts to bite?

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Anna: Industry reporting points to most Falcon 9

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missions winding down from around

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2028, with a limited number of flights

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continuing well past that. NASA's crew

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and cargo runs to the ISS are expected to

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keep flying on Falcon 9 through at least

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2030. Since human rating, a brand new

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vehicle for those missions isn't something

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anyone rushes.

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Avery: There's something almost poetic about this

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landing. The same week Roman flew on a Falcon

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Heavy.

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Anna: Genuinely, Roman rode one of the very rockets

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Musk is talking about eventually phasing out

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on what could well end up being one of Falcon

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Heavy's higher profile flights. And it's not

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an isolated signal either. We've already told

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you about Starbase, Louisiana. SpaceX's

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planned second Starship focused launch

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complex, and Starship's own Flight 14

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is still tracking toward, uh, no earlier than

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September 15th.

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Avery: So the plan really is get starship flying

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like Falcon 9 does now, then hand over the

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keys.

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Anna: That's the plan. As Musk describes it,

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whether starship's flight cadence actually

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gets there on anything like that timeline is

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very much the open question.

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Avery: Onto our next storey today. And this one's

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got some serious star power behind it,

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literally. Nobel Prize star power.

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Anna: This is a good one. Back in November last

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year, a, uh, South Korean research team

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published a paper suggesting the universe's

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expansion might actually, actually be slowing

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down, not speeding up. Which, if true,

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would upend a huge chunk of modern cosmology.

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Avery: That's the kind of headline that gets a lot

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of attention.

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Anna: It did, and it also got a lot of

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scrutiny. A team led by Phil Wiseman at the

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University of Southampton, working alongside

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Adam Reese And Brian Schmidt, two of the

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three scientists who shared the 2011 Nobel

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Prize in Physics for discovering the

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universe's accelerating expansion in the

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first place, which went back through the

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analysis and published a rebuttal in the

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monthly notices of the Royal Astronomical

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Society this week. And their finding,

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the universe is in fact still speeding up.

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Nobody's disputing that part. What they found

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was a specific flaw in the earlier study's

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method. It had effectively treated the age of

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a distant galaxy as if it were the age of the

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individual star inside it that later

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exploded as a supernova and hadn't properly

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accounted for the host galaxy's mass either.

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Avery: Which matters because.

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Anna: Because the whole technique relies on type

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1A supernovae, extremely bright,

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reliably behaved stellar explosions from

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white dwarf stars as standardised cosmic

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candles to measure distance. And from that,

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the universe's expansion rate over time.

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Get the underlying age or mass assumptions,

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even subtly wrong, and you can shift your

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final answer in a way that looks like new

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physics, when it's actually just an error

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creeping in upstream.

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Avery: So this isn't new data, it's a correction to

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how old data was read.

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Anna: Exactly. No new telescope, no new

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survey, just a more careful reanalysis of

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existing supernova observations. Which,

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fittingly, is precisely the kind of question

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Roman was built to help nail down for good

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with its own dedicated supernova time domain

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survey.

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Avery: Once it's up and running, dark energy remains

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undefeated.

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Anna: Then, for now, nobody's claiming to know

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what dark energy actually is. Only

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that, whatever it is, it's still doing what

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we thought it was doing.

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Avery: Next up, we're heading to Mars. Well,

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technically, just passed it to one of its two

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little moons, Themos, the

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Anna: smaller and more distant of Mars. Two moons.

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It's always been a Bit of an odd duck. It's

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shaped like a lumpy potato. It's got an

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unexplained depression near its south pole

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and its surface is oddly smooth and dusty for

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a body that small.

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Avery: Small. And somebody's finally worked out why.

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Anna: A team led by Sabina Radican, now at the

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Vri Universitite Brussels, working with

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Martin Uzi at the University of Bern,

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published the answer in Nature Astronomy. And

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this is the first published study to use

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actual Flyby Data from ESA's HERA mission,

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which swung past Deimos on its way out to the

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asteroid Dimorphos.

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Avery: What did they find?

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Anna: A single asteroid impact explains both

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quirks at once. They're simulations, about

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a hundred of them, each needing roughly a

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week of supercomputer time. Using a piece

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of impact modelling software the University

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of Bern has been developing for two

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decades, show an asteroid around

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320 metres across, hitting

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at a 45 degree angle is enough

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to carve out that south polar depression

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and scatter enough debris around the entire

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moon to explain the dusty regolith

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layer everywhere else.

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Avery: 45 degrees feels oddly specific.

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Anna: It's the sweet spot. Violent enough to

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genuinely redistribute material across the

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whole surface, but not so violent it would

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have shattered a moon this small entirely.

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Deimos, by the way, is basically a porous

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rubble pile rather than one solid rock.

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So getting that balance right mattered a lot

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in the models.

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Avery: One impact, two mystery, M solved.

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Anna: One impact, two mysteries. And a nice

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example of a spacecraft doing useful science

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on the way to somewhere else entirely.

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Hera's primary job is studying what NASA's

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DART mission did to Dimorphos. This

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Deimos flyby was almost a bonus stop on the

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way past.

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Avery: Alright, let's get everyone sorted for

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tonight, wherever tonight actually is for

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you.

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Anna: Venus is the headline act, and it's an easy

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one to find. Low in the west, west

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southwest, roughly 45 minutes after

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sunset from Sydney tonight. Sunsets

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around 5.32pm, so you're looking

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from about a quarter past six. Wherever

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else you are, just use your own local sunset

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and add the same 45 minutes.

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Avery: How long do people have before it sets?

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Anna: Uh, not long. Venus is following the

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sun down pretty quickly at the moment,

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setting only 90 minutes after sunset. So

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don't dawdle. It's sitting close to Spica

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right now, too. Tonight's basically a

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preview, because the real close pass happens

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tomorrow night, September 1, when the two

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will be less than 2 degrees apart. It's

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heading toward its brightest of the year

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later in September So this is really just the

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opening act.

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Avery: What about Saturn? We've called it the

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reliable one a lot lately.

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Anna: Saturn's actually graduated to a better slot.

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It's now rising close to sunset and staying

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up for the most of the night, sitting in

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aquarius at magnitude 0.3,

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brighter than anything else nearby in that

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stretch of sky. Even a modest telescope

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will show the rings clearly separated from

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the disc now that they've opened up to about

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7.5 degrees, a big improvement

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on how flat and hard to read they were last

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year. It's closing in on opposition on

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October 4, so it only gets better from

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here. Great target either hemisphere.

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Avery: And for the early risers, Jupiter's

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just

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Anna: returned to the morning sky after being lost

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in the Sun's glare, so it's back as a pre

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dawn target. Low in the east, best

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windows roughly 4 to 6 in the morning.

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Mars is out there too, fading a uh, bit these

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days in that same pre dawn eastern sky.

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And the moon waning gibbous tonight,

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still bright. It was sitting right next to

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Saturn the last couple of nights and it'll

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keep thinning out through the week.

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Avery: One quick standing reminder before we go.

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Since we're talking about bright things low

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Anna: near the horizon, always worth repeating.

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Whenever you're pointing anything, even just

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your eyes near the Sun's position in the sky,

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sunrise, sunset or any direct solar

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viewing, make sure any filter you're using is

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certified to ISO

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123122.

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Ordinary sunglasses are nowhere near enough

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protection. Venus and Saturn ah, are

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perfectly safe to look at anytime. Obviously

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this one's just a standing habit worth

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keeping. Sharp.

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Avery: Good habit to keep sharp indeed.

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And that's a show for today. The Nancy Grace

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Roman Space Telescope safely away and headed

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for deep space. SpaceX uh, signalling the

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eventual end of the Falcon 9 era. Two Nobel

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laureates defending an accelerating universe,

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one very old asteroid strike solving two

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mysteries on Deimos, and everything you need

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to get outside tonight.

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Anna: If you enjoyed today's episode, the best

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thing you can do for us is leave a rating or

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00:16:18.840 --> 00:16:21.080
review wherever you're listening and share it

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with a fellow space nerd. Full show notes,

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sources and links for every storey we covered

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today are @astronomydaily IO

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and you can find us on social media. We're

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AstroDaily Pod pretty much everywhere.

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Avery: We'll be back tomorrow with more space and

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astronomy news. Until then, keep looking up.

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Anna: See you next time. Clear skies.

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Avery: Mhm.

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Anna: The storey.