JCC The All-New, All-Different JCC Astronomy Thread

The Carl Sagan Observatory.

 

All of these predictions have been subsequently confirmed, implying that there was a period of exponential expansion prior to the start of the hot Big Bang.

But how long did that period last, and what came before it?

For the first question of how long it lasted, that’s a question where we only have a lower limit, but there is no upper limit set by data. Inflation must have resulted in the Universe “doubling” in size at least a few hundred times, but if each “doubling” only takes something like 10-35 seconds, then that only tells us that the Universe must have undergone inflation for at least ~10-32 seconds. It could have lasted nanoseconds, seconds, years, trillions of years, googols of years, or even longer before ending and giving rise to the hot Big Bang.

When do we start counting the age of the Universe

 

Construction has begun on the Square Kilometer Array radio telescope

Conceived in the 1990s, and further developed and designed by the late-2010s, when completed sometime in the 2020s it will have a total collecting area of approximately one square kilometre. It will operate over a wide range of frequencies and its size will make it 50 times more sensitive than any other radio instrument. If built as planned, it should be able to survey the sky more than ten thousand times faster than before. With receiving stations extending out to a distance of at least 3,000 km (1,900 mi) from a concentrated central core, it will exploit radio astronomy's ability to provide the highest-resolution images in all astronomy.

 

During the upcoming weeks, a newly-discovered comet will be making a relatively close approach to the Earth. On Feb. 1, comet C/2022 E3 (ZTF) will pass to within 28 million miles (42 million km) of our planet, its first approach in 50,000 years. While this will no doubt entice many skywatchers to attempt to view the comet, whether or not one will actually be able to see it will depend on a variety of factors including location and light pollution from both natural and artificial sources.

project's website(opens in new tab) or on its YouTube channel.

From here

 

A win for MOND

The idea of dark matter is not destroyed, but it gets a black eye here.

 

Green-colored comet to swing close to Earth for first time in 50,000 years

https://www.nbcnews.com/science/space/green-comet-approach-flyby-earth-rcna65202

 

Also, we are finally going to test space-based solar power:
https://www.popsci.com/technology/caltech-solar-energy-power-satellite-prototype-launch/

 

A large Optical SETI experiment searching for alien objects within our solar system

 

Extensive solar storm today. Seeing posts on social media of Aurora Borealis as far down as Virginia, but also over at the British islands. Great visibility in Minnesota and rest of the US/Canadian border.

 

https://www.bbc.co.uk/news/science-environment-65061818 - massive asteroid to pass between the Earth and Moon this weekend. That's a bit too close for my comfort!

 

Just remember all the planets of the Solar System can fit between Earth and the Moon.

 

Is there some way to post youtube shorts correctly?

Anyway, the largest planet we know of.

 

Yeah, that video is almost certainly wrong. 752 Jupiter masses would be well above the threshold for a star, and I can't actually turn up anything reliable saying that is the mass, and the things that do talk about the mass put it at an estimated roughly 15-20 Jupiter masses. And that's even if that's in contention, because there's other work suggesting it's a much smaller planet creating a disk disturbance or a disk feature entirely it seems.

In any case, the 752 Jupiter masses seems to have been plucked from nowhere as far as I can tell (it may be coming from something else, but not about that "planet" it seems).

 

NASA says it's 752 Jupiters.

Though i recall now if Jupiter were what, 80 times more massive it could achieve fusion?

In the comments section of the vid:

It has a mass of 3.1 Jupiters...The star it orbits has a mass of 752 Jupiters. Update: It has a mass of up to 33 Jupiters, and mostly likely 17.5. The '752' figure is an error, it's stars mass is 2526 Jupiter masses or 2.4 solar masses

 

More reliable NASA doesn't say that 752 Jupiter masses bit, but does flag this as a controversial planet, so its existence isn't particularly secure (if there's not citations then there's an issue exactly due to things like this). And heck, it manages some fusion at about 13 masses as a brown dwarf, it's just 80 Jupiter masses or so to fuse helium

 

It appears the Andomeda galaxy has been knocked down a peg

In terms of mass, less "dark matter". I wonder how MOND folks will respond.

 

@JEDI-SOLO
This is probably the best thread for posts about meteor showers.

 

Right on man always so helpful!

Lyrids shower started tonight and will peak on the 22nd-23rd. Not sure how bright the moon will be then.