Hubble is 30 years old, and was probably based on a military spy satellite (KH-11) design.
I agree it was a milestone for astronomy, but it's been very long without any progress since. Why don't we at least have 4 more Hubbles in orbit?
I agree it was a milestone for astronomy, but it's been very long without any progress since. Why don't we at least have 4 more Hubbles in orbit?
Hubble - Visible / NIR, 1990 - Present
Compton - Gamma Ray / Xray, 1991 - 2000
Chandra - Xray, 1999 - Present
Spitzer - Infrared, 2003 - 2020
But again, even though it was "visible" it did not have many pretty pictures because the mission was looking at brightness variations in particular stars (planet transients).
> There's also JWST
Which is 15 years late and still on the ground.
The reason is pretty simple, there's no money to be made. Your potential customers are researchers scraping together grant money. There's no way to make enough to cover the CapEx and OpEx of a space telescope let alone make a profit.
There's no magic SpaceX fairy dust you can sprinkle on a project to change that calculus. The launch cost is a small portion of the total CapEx of a space based instrument.
Meant to launch in 2026.
"The PLATO payload is based on a multi-telescope approach, involving 26 cameras in total: a set of 24 "normal" cameras organised in 4 groups, and a set of 2 "fast" cameras for bright stars. The 24 "normal" cameras work at a readout cadence of 25 seconds and monitor stars fainter than apparent magnitude 8. The two "fast" cameras work at a cadence of 2.5 seconds to observe stars between magnitude 4 to 8. The cameras are refracting telescopes using six lenses; each camera has an 1,100 deg2 field and a 120 mm lens diameter. Each camera is equipped with its own CCD staring array, consisting of four CCDs of 4510 x 4510 pixels.
The 24 "normal cameras" will be arranged in four groups of six cameras with their lines of sight offset by a 9.2° angle from the +ZPLM axis. This particular configuration allows surveying an instantaneous field of view of about 2,250 deg2 per pointing. The space observatory will rotate around the mean line of sight once per year, delivering a continuous survey of the same region of the sky."
I posted a sibling comment, but both the proposed HabEx and LUVOIR space telescope designs would be visible-light.
The next Roman optical space telescope is slated for 2025.
The mirror in Hubble is 2.4 meters
Large ground based telescopes now have mirrors in multiple segments with motors keeping them at the right curvature.
The largest has 10.4 meter mirror. That is about 11 times larger area than Hubble.
https://en.wikipedia.org/wiki/List_of_largest_optical_reflec...
One of the original reasons for Hubble was to have a telescope above the atmosphere. The atmosphere distorts the light as it passes through making stars "twinkle."
Now we we use a laser beam to energize sodium atoms in the upper atmosphere. We see how that is distorted by the atmosphere so that with software we can cancel it out.
https://en.wikipedia.org/wiki/Laser_guide_star
Combined with lucky imaging where instead of taking a single long exposure we take thousands of images in the 100 millisecond range. We can toss out the images where the atmosphere was moving a lot and combine the other good images.
Kepler, Spitzer, Herschel, WISE and more. I agree that there ought to be more by now but its not like we did not see 'any progress'. Today we know hundreds of earth sized planets in the galaxy. If that's not progress, I feel the telescopes JamesWebb and NancyGraceRose will only disappoint you ;)
Hubble was launch in 1990, and have 5 servicing missions for repairs and upgrades, with the last one being in 2009.
An exact clone of Hubble is not nearly as useful as the first one, so it is reasonable to put your resources into a novel telescope. Unfourtuantly that telescope hit some scheduling challanges.
Not to mention all the other space telescopes https://en.m.wikipedia.org/wiki/List_of_space_telescopes
Which includes a gravitational telescope prototype.
NASA is well funded, not underfunded. It receives over three times the funding of ESA by comparison.
Why aren't the Europeans funding their scientific institutions better? Because the combination of soaring entitlement costs and stagnant growth robs them of the necessary tax revenue for that. Which is exactly what's happening in the US, and it's going to get a lot worse yet. The US has a bit less of an excuse, seeing as it could safely cut $200b off of its military. However, that $200b spread around to every squeaky wheel still won't go very far (it's equal to a mere ~2.3% of total government spending), you might be able to fairly boost NASA's budget by $3b per year if you slashed the military. Back in reality, that $200b in cuts should probably be entirely allocated to healthcare, which brings us right back to the central issue of priorities; and the Europeans know that quite well, which is why ESA is poorly funded.
Across all industries the average R&D budget is around 4%. When you look at the US R&D budget it's about 3% of the annual budget with 2% going directly to Military R&D and 0.5% going to defense and other military adjacent R&D. That's not entirely accurate thought because the Military budget for R&D also encompasses Training and Exercises. So only a fraction of that 2% is used for actual R&D.
That missing 1% is 3x Nasa's budget and 1.5 the DOD's.