Earth-bound exoplanet hunter's eyes blink open

Re: Question

This project cost £2.5 million.

Kepler answered 'how common are exoplanets'. This project will answer 'what are the easiest largish exoplanets to observe'. The TESS satellite, launching in summer 2017, which is much the same as this project but done from space at about a hundred times the cost, will produce a complete catalogue of exoplanets around bright stars, down to half the size of the ones found by this project.

The problem with Kepler is that it looked at such faint stars that it took inordinate effort to follow up the results; if you find planets around significantly brighter stars, you can do radial-velocity follow-up with moderate telescopes (which confirms that you've found a planet rather than a sunspot of unusual size, and tells you whether there are other planets in the system), there's the possibility of doing differential spectroscopy from space to find out what their atmospheres are made of, and if the stars are bright because they're close there's the possibility of directly imaging the planets with things like the Gemini Planet Imager.

Re: Question

" I just don't quite get how they attract funding whereas SETI struggles for every dollar, a project which I think could in time reap rewards whereas this duplication seems rather strange????"

I disagree that this is a "duplication," but to address your basic question: it's about results and interest.

Even Kepler, which spots little wiggles of light from stars and gives results as dull charts and tables, is producing newsworthy, publishable data. It finds ALIEN EARTHS, which are TOTALLY like EARTH! (Except for being 5 times as massive, having surface temperatures over 500K, and a 1000-bar hydrogen atmosphere.) Mars rovers attract attention because they're plucky and they return cool pics of Martian vistas (and have Twitter accounts now!). Cassini buzzes distant moons and, yep, returns cool pics. Rosetta is hanging out with a space duck and had this attention-grabbing story about the stalwart little lander that bounced across the surface of a FRICKIN' COMET and then spent its last, dying joules of energy sending home scientific data. ("3% ammonia...getting cold now...2% carbon monoxide...Tell Wanda and the kids I love them..." [static]) Hubble...ZOMG, Hubble pictures! Pillars of Creation! Carina Nebula! The mysteries of the universe boiled down to cool pics that get published by every newspaper! And against all that, SETI peeps out, "Didn't hear anything today, either."

Hubble's actually a decent place to start for looking at "Why Project X instead of SETI"? Hubble has scientists going to bat for it. Lots of astronomers and astrophysicists and, heck, probably even astrologers get publishable data from buying time on Hubble. When the annual funding scramble hits, Hubble has legions (and lobbyists) selling its case to NASA administrators and Congresscritters. Every grad student hoping to write their doctoral thesis from Hubble results will submit letters to Congress.

Meanwhile, Hubble has public people power, too. Hubble's last servicing mission was an enormous pain in the butt for NASA, but all the roaring crowds demanding their awesome Hubble pics for another decade wouldn't let the plucky space telescope die with the shuttles. The usual nasty letters from fiscal conservatives decrying waste of taxes on crazY cOmmie SCience hipPIes instead of NATIONAL DEFENSE didn't stand a chance against the tidal wave of public support created by a reprint of the Pillars of Creation.

SETI? "Nope, didn't see an ET today, either. Also, one of our grad students published a paper showing, in a very clever fashion, that we didn't find ET last year, either. Can I have another $10 million to survive?" That's harder to sell.

Don't get me wrong, I like SETI. I'd like a warning to evacuate the cities before our new Zeta Reticulan Overlords show up. It's important. But without another Contact movie to help sell it, SETI doesn't have the academic backing, lobbyists, and star power of programs that produce flashier results.

Re: So they can see planets so far away but no high quality Moon pics ?

Well actually no, they can't "see" planets at those distances at all. They're inferring their existence by looking at the changes in the spectra of the stars they're orbiting. From this they can work out, or at minimum an educated guess of , the mass, temperature, orbital speeds and possibly even what the planet is primarily made of. You won't be seeing any pics anytime soon either. I've heard it described as like trying to see a candle right next to a 40kW searchlight from 1 mile away.

Re: So they can see planets so far away but no high quality Moon pics ?

"As well as Mars, Jupiter, Venus... no high quality uncensored pictures from nearby planets..."

It is an interesting syndrome wherein a person not only refuses to look for information that's at their fingertips via Google** Image search, but then leaps to the conclusion that because they didn't see the information they didn't search for it thus doesn't exist.

Databases of photos at meter resolution of Mars and the Moon are available online for free, as are the (over-meter scale) results from Galileo, Cassini, and other space probes. Since the 1970s-1980s, the attitude with sharing space probe has at least partly changed from "It belongs to the lead investigator, who gets first dibs on publishing results," to "Taxpayers funded these public works, so they get all the data." ESA, NASA, USGS, and other organizations thus have websites dedicated to specific missions and/or planets filled with all the raw and processed photos you could ask for.

**Or Bing, or Yahoo!. I don't want to exclude any alternative search life choices.

Re: So they can see planets so far away but no high quality Moon pics ?

"As well as Mars, Jupiter, Venus..."

And none of Uranus? Uh hurr, uh hurr

Signed

B. BUTThead

Re: From twice to eight times 'Super Earths' or ...

Sorry, we didn't invent the term super-Earth, but others have run with it.

Simplistically speaking a super-Earth is a planet that's thought to be rocky, but is significantly larger than Earth. If you look at our Solar system you have the rocky planets (Mercury, Venus, Earth, Mars), the Ice Giants (Neptune, Uranus) and the Gas Giants (Saturn, Jupiter). To first order these classes are distinguishable based on their measured density.

NGTS is looking for rocky planets (as deduced from their measured density), but fundamentally is limited to finding planets that are ~2x Earth radius (ie. 8x Earth mass assuming Earth density).

That's about the best that can be done from the ground. Finding 1x Earth radius / 1x Earth mass planets is really only possible from space, and that's ~100x more expensive. A small number have been found, but they are in short-period orbits, and unlikely to be habitable.

If you're really looking for true analogs of our Earth (ie. a 1 Earth mass planet, in a 1 Earth year orbit about a 1 Sun mass G-class star), then the space missions mentioned here (Kepler, TESS) are not capable of detecting these. You will have to wait until PLATO flies in 2024, then wait maybe a decade after that for its findings to be verified.