YHK - yet another hacker news clone

A 12-year sequence of telescope images of a star and four planets orbiting

57 points mariuz 9 hours ago 11 comments

tocs3 6 hours ago | parent

Amazing. Scrolling down one of the comments has an animation of starts around the center of the Milky Way. I have seen a few short ones of nebulae. There should be much much more of this sort of thing.

I appreciate that scientist are not always after the pretty pictures. They can be expensive, do not always give the data needed, and the experiments do not always produce data that has obvious pretty picture potential. Still, for the average non professional scientist (me) the pictures are about all I will ever get out of the science.

swiftcoder 24 minutes ago | parent

A good chunk of science communication centres around how one conveys the wow factor to folks who aren't already obsessed with the particular field. Images like this really help sell it to the rest of us

turtletontine 22 minutes ago | parent

The galactic center data actually proved there was a supermassive black hole at the center of the Milky Way, and weighed it precisely from those stars motions. The name of the account that posted that animation (Sagittarius A*) is the name of that supermassive black hole.

This work earned the 2020 Nobel Prize in Physics: https://www.nobelprize.org/prizes/physics/2020/summary/

317070 1 hour ago | parent

Wow, in terms of angle, how far are these planets separated from the star?

I always thought we would never be able to image something like that. The distances would be too small and the contrast too large to figure something at the resolution we can get on earth. I'll need to read up on how this was done.

ceejayoz 53 minutes ago | parent

https://en.wikipedia.org/wiki/HR_8799

ryandrake 42 minutes ago | parent

Yea, the planets are gigantic, and in distant orbits from their star. I don't think we even have the ability yet to directly image exoplanets much smaller than, say, Saturn, or closer to their stars than Saturn.

jcims 41 minutes ago | parent

TL;DR - Two inside (16, 26AU) and two outside (43, 69AU) Pluto's orbit (39AU). They are all estimated to be a bit bigger than Jupiter.

turtletontine 15 minutes ago | parent

The scale bar (20 AU) represents 20 time the distance between the Earth and the sun. This star is about 41 parsecs away, so the angular size of that scale bar is about half an arcsec. (One degree is split into 60 arcminutes, one arcminute into 60 arcseconds. Just like a clock).

That angle is about the diameter of a US quarter coin seen from 11km (7mi) away.

Kaxo 22 minutes ago | parent

The noise from the blocked-out star noticably decreases in 2017. Is that due to changes in the stars' activity cycle, or is that due to better processing/capture technology?

rietta 13 minutes ago | parent

I do not know, but my best guess would be an improved post processing algorithm was introduced.

Sarkie 11 minutes ago | parent

They need to remove that one frame