r/space

If aliens 2,000 light years away just built a telescope powerful enough to see Earth, they’d be watching the Roman Empire right now. But think about this: the light that left Earth TODAY is already traveling toward them, sitting somewhere in that 2,000 light year corridor. So if their telescope could intercept light at different points along that path rather than just waiting for it to arrive, would they be sampling different moments in Earth’s history. The further out they reach, the more “recent” the Earth they see?

In the SpaceX stream today they brought on a guy who is supposed to be on an upcoming SpaceX manned mars flyby. A MANNED FLYBY? They are going to spend two months going there, two months back (6 months there, 6 months back), getting absolutely BUTT BLASTED by radiation and they don’t even get to claim a reward of landing and stretching legs and history book page? Wtf

Another major workplace injury occurred at SpaceX last year:

SpaceX crane collapse in Texas being investigated by OSHA.
PUBLISHED THU, JUN 26 2025 7:54 PM EDT UPDATED THU, JUN 26 2025 11:27 PM EDT
The crane collapse was captured in a livestream by Lab Padre on YouTube, a SpaceX-focused channel. Clips from Lab Padre were widely shared on social media, including on X, which is owned by SpaceX CEO Elon Musk. It wasn’t immediately clear whether any SpaceX workers were injured as a result of the incident. Musk and other company executives didn’t respond to a request for comment.
https://www.cnbc.com/2025/06/26/spacex-crane-collapse-in-texas-being-investigated-by-osha.html

A heads up about how multi-billion dollar corporations operate. Whenever there is an accident where people were potentially injured, if there were no injuries the company quickly gets out there were no injuries. For instance like how SpaceX quickly got out there were no injuries during the static test explosion. But if the company makes no comment on the accident, it’s a good chance there were injuries. And the longer the company says nothing about the accident the more likely it becomes there were serious injuries.

Article from 2023 detailing SpaceX culture downplaying worker safety:

A REUTERS INVESTIGATION
At SpaceX, worker injuries soar in Elon Musk’s rush to Mars.
SpaceX rockets on a launchpad near Brownsville, Texas. The facility had a worker-injury rate six times the space-industry average in 2022. REUTERS/Go Nakamura
Reuters documented at least 600 previously unreported workplace injuries at Musk’s rocket company: crushed limbs, amputations, electrocutions, head and eye wounds and one death. SpaceX employees say they’re paying the price for the billionaire’s push to colonize space at breakneck speed.
By MARISA TAYLOR
Filed Nov. 10, 2023, 11 a.m. GMT
https://www.reuters.com/investigates/special-report/spacex-musk-safety/

NASA's Ingenuity Mars Helicopter completed 72 historic flights since first taking to the skies above the Red Planet.

On April 19, 2021, NASA's Ingenuity Mars Helicopter made history when it completed the first powered, controlled flight on the Red Planet. It flew for the last time on Jan. 18, 2024.

Designed to be a technology demonstration that would make no more than five test flights in 30 days, the helicopter eventually completed 72 flights across nearly three years, soaring higher and faster than previously imagined. Ingenuity embarked on a new mission as an operations demonstration, serving as an aerial scout for scientists and rover planners, and for engineers ready to learn more about Perseverance’s landing-gear debris.

In its final phase, the helicopter entered a new engineering demonstration phase where it executed experimental flight tests that further expanded the team’s knowledge of the vehicle’s aerodynamic limits.

The international FLAMINGO project (Full-hydro Large-scale structure simulations with All-sky Mapping for the Interpretation of Next Generation Observations) has just released one of the biggest cosmological simulation datasets in history — more than 2.5 petabytes of data, roughly equivalent to 500,000 HD movies.

Led by researchers from Leiden University and the Virgo Consortium, FLAMINGO simulates the full evolution of the Universe from the Big Bang to the present day (13.8 billion years). Unlike traditional dark-matter-only simulations, it includes full hydrodynamics with:

- Ordinary (baryonic) matter — stars, galaxies, gas, cooling, star formation, supernovae, and AGN feedback.

- Dark matter.

- Massive neutrinos (modeled explicitly with particles).

- Dark energy.

Key specs of the flagship runs:

- Largest box: **2.8 Gpc** (~9 billion light-years) on a side.

- Up to **300 billion particles** (3 × 10¹¹).

- Three resolution levels, with the fiducial models carefully calibrated (using machine learning) to match the observed galaxy stellar mass function and cluster gas fractions at low redshift.

- Multiple variations exploring different feedback models, stellar mass functions, cosmologies, and neutrino masses.

- Full-sky lightcone outputs (HEALPix maps) for up to 8 observers, plus snapshots, halo/galaxy catalogues, and power spectra.

The entire suite includes 22 hydrodynamical + 16 gravity-only simulations. It was run on the COSMA 8 supercomputer (DiRAC, Durham University) using the highly efficient SWIFT code, consuming over 50 million CPU hours.

The FLAMINGO project consumed more than 50 million CPU hours (also called core-hours or processor hours) in total.

This figure is the most commonly cited value across official announcements from Durham University, Leiden University, and the Virgo Consortium for the full suite of simulations (hydrodynamical + dark-matter-only runs).

Key Details:

- The simulations were run on the COSMA 8 supercomputer (part of the DiRAC facility at Durham University, UK).

- The code used, SWIFT, scaled efficiently to 30,000–65,000 CPUs simultaneously.

- One of the largest flagship runs (L2p8_m9, the 2.8 Gpc box) took approximately 31 million core-hours and ran for about 42 days on ~30,000 CPUs.

- Another high-resolution run (L1_m8) required around 17 million core-hours.

- The full project (including all variations, calibrations, and the 2026 data release with >2.5 petabytes of data) pushed the total well above 50 million CPU hours.

For context, this is equivalent to many centuries of computing time on a single high-end CPU — only possible thanks to massive parallelization on a top-tier supercomputer.

Why it matters:

FLAMINGO bridges small-scale galaxy formation physics with enormous cosmic volumes needed for precision cosmology. It helps interpret data from telescopes like JWST, Euclid, DESI, and LSST, test models of structure formation, quantify baryonic effects on the matter power spectrum (up to ~20% suppression), and address tensions in cosmology.

The full dataset is publicly available (with selective download tools because of its massive size). Check the official site and the 2026 data release paper for details.

Links:

- Official website: https://flamingo.strw.leidenuniv.nl/

- Data Release Paper (arXiv 2026): https://arxiv.org/abs/2604.24324

- Main Project Paper (2023): https://arxiv.org/abs/2306.04024

This is a new golden age for computational cosmology. What do you think — will simulations like this finally help solve the Hubble tension or other big questions?!

I would like to take the question somewhat sincerely, albeit with a pinch of salt.

If you want to analyse this question scientifically first we have to look at the assumptions of the question.

The biggest assumption in the question is that there is a big bang.

We have been seeing "Little Red Dots" through the recently launched James Webb telescope. These seem to be very distant quasars or active Galactic nuclei that also seem to have a red shift greater than the age of the universe.

The second biggest assumption in the question is that there is a notion of past present and future for the universe. This seems very benign and obvious at first.

But we literally seem to have no clue on how the universe or its galaxies are maturing over time. A prior assumption was that the black hole in the centre of the galaxy slowly but surely grows larger with time but again we are seeing larger black holes in galaxies much further away and in the past. Even something as simple like the spin of a galaxy has slipped our brightest minds for over half a century. This does not mean that the universe did not have a start but it definitely calls into question the hand wavy inflation to explain how universe came to be.

The third assumption is that it is a fair question and the answer is within the realm of comprehensibility of a human mind. This is again assumption that we would not see in most questions to ask, but in existential questions especially once that are so steeped in reality and data, this becomes significant. We would need an answer that would satisfy us. And the truth for us could a satire of the real truth because of our minds limitations.

Another important factor over here is the nature of empty space itself. Every time we look at it, it seems to contain more than we think it does. It can stretch and pull and have particles becoming and unbecoming inside it. All while slowing time around it and shrinking black holes.

All this together puts quite an incomplete picture of the universe. It's uncertain if it's a singular explosion then expansion in space and collapse into galaxies around black holes we're told brought us here, has problems at every step of the way. Therefore the assumptions of the question as a whole stand on weak footing.

So I think this is an important question but an ill formed question which is why it is disliked. However I think it shows the various limits of our understanding of our reality and the universe in which we live.

To summarise, yes we don't know. And what all that we don't know shows us how ill equipped we are to ask and answer this question.

Hey everyone,

I am working on a Mars colonization project. During the process of extracting oxygen, I also end up with methane (CH4) as an output.

While having methane is a big plus, storing it is a major issue. Bringing large, dedicated gas cylinders or tanks from Earth is highly impractical due to mass and cargo constraints. My proposed solution is to store this methane directly inside the rocket's own empty tanks. I know that for modern rockets, the methane needs to be cryogenically cooled to around -165 C•, but in this situation, it seems like the best option.

I have two specific questions regarding this approach:

1. Import and Export: Is it technically possible to both import (load) and export (draw back) gas directly from a spacecraft's primary propellant tanks?

2. Feasibility: Do you see any major technical issues or better alternatives with this specific storage method?

Thanks for your insights!