Author: Andrew

An electrical engineer, amateur astronomer, and diver, living and working on the island of Hawaiʻi.

Scientists Build First Map of Hidden Universe

W. M. Keck Observatory press release…

A team led by astronomers from the Max Planck Institute for Astronomy has created the first three-dimensional map of the ‘adolescent’ Universe, just 3 billion years after the Big Bang. This map, built from data collected from the W. M. Keck Observatory, is millions of light-years across and provides a tantalizing glimpse of large structures in the ‘cosmic web’ – the backbone of cosmic structure.

The Cosmic Web
3D map of the cosmic web at a distance of 10.8 billion light years. Credit: Casey Stark (UC Berkeley) AND Khee-Gan Lee (MPIA)
On the largest scales, matter in the Universe is arranged in a vast network of filamentary structures known as the ‘cosmic web’, its tangled strands spanning hundreds of millions of light-years. Dark matter, which emits no light, forms the backbone of this web, which is also suffused with primordial hydrogen gas left over from the Big Bang. Galaxies like our own Milky Way are embedded inside this web, but fill only a tiny fraction of its volume.

Now a team of astronomers led by Khee-Gan Lee, a post-doc at the Max Planck Institute for Astronomy, has created a map of hydrogen absorption revealing a three-dimensional section of the universe 11 billions light years away – the first time the cosmic web has been mapped at such a vast distance. Since observing to such immense distances is also looking back in time, the map reveals the early stages of cosmic structure formation when the Universe was only a quarter of its current age, during an era when the galaxies were undergoing a major ‘growth spurt’.

The map was created by using faint background galaxies as light sources, against which gas could be seen by the characteristic absorption features of hydrogen. The wavelengths of each hydrogen feature showed the presence of gas at a specific distance from us. Combining all of the measurements across the entire field of view allowed the team a tantalizing glimpse of giant filamentary structures extending across millions of light-years, and paves the way for more extensive studies that will reveal not only the structure of the cosmic web, but also details of its function – the ways that pristine gas is funneled along the web into galaxies, providing the raw material for the formation of galaxies, stars, and planets.

Continue reading “Scientists Build First Map of Hidden Universe”

The Moon and Jupiter

Tomorrow morning the Moon and Jupiter will be close. The Moon will rise first, followed by Jupiter at 01:34 to be almost 65° above the eastern horizon at sunrise. The Moon will be about 32% illuminated and about 6° above a bright Jupiter. The next day the Moon will have moved to the other side of Jupiter and be a bit further apart, about 10° separation.

Hurricane Ana

Here we go with hurricane two for the season. The forecast continues to put the island of Hawaiʻi directly in the path of the storm. If anything the news is a little worse, with the storm tracking up the west side of the island.

I suspect we will need to take this storm even more seriously than Iselle. Time to put the patio furniture away again, and check around the house for anything loose that may be an issue. Pick a few of my ripe grapefruits as well.

The observatory is reactivating the response plan we had a chance to refine and put into action for hurricane Iselle. Time to batten down the hatches, somewhat literally in the case of the summit facility. We are working on the Keck 1 shutter today, checking the seals and resetting the fully closed position to deal with some leaks.

Hurricane Ana Foirecast Path
The predicted path for hurricane Ana from the Pacific Hurricane Center

The List

I usually have a list of things that need done on the summit. Mostly manini things, stuff that takes a few minutes, or maybe an hour. Not enough to justify a day on the summit, this stuff can usually wait for a week or two, until I find time. When a more serious issue takes me to the summit, something that must be done, it may take an hour, or half a day. When the main thing is done I always have the list to fill in the remainder of the day.

Summit To Do List
The list of things to do on the summit.
There were three things on the list, one that had to get done. No problem, I will be on the summit tomorrow. A phone call added another item to the list. A co-worker stopping by my desk with a favor to ask… One more item added. When the end of the day was finally upon me, the list had grown to ten items. It usually works that way.

A small yellow-lined piece of paper pulled from a pad, a scrap that would rule my day on the summit. I slip the list into my left breast pocket beside a black ball-point pen.

Attach a data logger to the K2 shutter drive controllers and move the top shutters. The data looks… Ummm… interesting. That will wait for another day to analyse. The shutters have been faulting out a bit lately, there is something wrong with the VFD drives, but I am not sure what. Hopefully the answer is in the data. Much of the morning is consumed with getting the test done.

Align the WYKO interferometer under the AO bench… No problem, takes five minutes… After I gown up to enter the AO enclosure. I can replace the wave front camera controller while I am in there, just swapping the unit with the controller from the development lab at headquarters. Alignment complete, nice fringes on the video monitor… Sam will be happy with that.

Time for lunch and a game of cribbage, a busy day makes this break all that much more enjoyable, It is a fun game, even if we do lose. We do not keep score, we play for fun and bragging rights for the day. All is forgotten a day later, with years of experience the skill level is pretty even and everyone takes a turn winning or losing.

A tour at 1pm, some family friends from Portland getting a tour of the telescope, always fun. A meeting at 3pm… I forget what for now… It must have been terribly important. The day was just a mite hectic, hurrying from task to task. Slowly the list dwindled as I cross off items.

As we headed down the mountain, I pulled the now well tattered list from my pocket. Not complete, a couple items will wait for another day. But still… A sense of satisfaction, of accomplishment. None of these tasks were of major importance, none would stop the telescope from going on-sky that night, just the routine minutiae of keeping the telescopes operating.

The First Storm of Winter on Mauna Kea

It is currently snowing on the summit. Not just a dusting this time, but a real blanket of white on the mountain. Poliʻahu has returned to the summit. The forecast is calling for up to three inches of white before tomorrow morning.

We just got word that the Keck summit crew is abandoning the summit. They are leaving before the conditions get worse.

A photo from a UKIRT webcam is below. I would post one from our Keck cameras, but the camera windows are covered with blown snow and ice. I have a new all-weather webcam, a full pan-tilt-zoom unit to install, but it is still sitting in a box at the summit. Personally I am not planning being up until Wednesday, I wonder if the snow will still be there, fresh snow on the mountain is always pretty.

Snow on Mauna Kea
The first winter storm on Mauna Kea for the 2014-2015 season blankets the summit in white.