All posts by Tom

UGC 477

ugc477

There are a few different catalogs listing space objects.   UGC stands for Uppsala General Catalogue of Galaxies and is a catalog of galaxies to a limiting diameter of 1.0 arcminute and/or to a limiting apparent magnitude of 14.5 on the blue prints of the Palomar Observatory Sky Survey (POSS). Coverage is limited to the sky north of declination -02.5 degrees.

From Hubble (via NASA)

This striking NASA/ESA Hubble Space Telescope image captures the galaxy UGC 477, located just over 110 million light-years away in the constellation of Pisces (The Fish).

UGC 477 is a low surface brightness (LSB) galaxy. First proposed in 1976 by Mike Disney, the existence of LSB galaxies was confirmed only in 1986 with the discovery of Malin 1. LSB galaxies like UGC 477 are more diffusely distributed than galaxies such as Andromeda and the Milky Way. With surface brightnesses up to 250 times fainter than the night sky, these galaxies can be incredibly difficult to detect.

Most of the matter present in LSB galaxies is in the form of hydrogen gas, rather than stars. Unlike the bulges of normal spiral galaxies, the centers of LSB galaxies do not contain large numbers of stars. Astronomers suspect that this is because LSB galaxies are mainly found in regions devoid of other galaxies, and have therefore experienced fewer galactic interactions and mergers capable of triggering high rates of star formation.

LSB galaxies such as UGC 477 instead appear to be dominated by dark matter, making them excellent objects to study to further our understanding of this elusive substance. However, due to an underrepresentation in galactic surveys — caused by their characteristic low brightness — their importance has only been realized relatively recently.

Text credit: European Space Agency
Image credit: ESA/Hubble & NASA, Acknowledgement: Judy Schmidt

Watch the Transit of Mercury

There are a number of sites offering live coverage of the transit all will be good.  Here are the places I will be watching.  Along with actually viewing the transit for myself if the weather cooperates (??). I managed to get a peek through binoculars in between clouds.

Coverage should start about 10:00 UTC / 6 EDT and the transit from about  11:12 UTC / 7:12 a.m. and 18:42 UTC / 2:42 p.m. EDT

From the Griffith Observatory:

ESA has a fantastic list of events!

From the Solar Dynamics Laboratory.

From MIT Wallace Observatory

From NASA TV (updated the link):


Broadcast live streaming video on Ustream

The Transit is Coming

Tomorrow the planet Mercury moves along the face of the sun in what is known as a transit and we can see it. The Mercury transits occur about every 13 years.

First – DO NOT EVER look at the sun without ADEQUATE eye protection!!!!!

If it is cloudy where you are, no worries, check back here tomorrow for links for on-line sources.  Today a couple of video’s.

The first from Physics World entitled, Guide to the transit of Mercury 2016:

and the second from Science@NASA, an updated version of the video I put up a week ago titled, ScienceCasts: The 2016 Transit of Mercury (updated):

Also here’s a pdf with great information from the US Naval Observatory.

Peake At The Controls

Tim Peake takes control of the ESA’s Mars rover prototype named Bridget located in the UK from the International Space Station.

He controlled the rover for two hours and even drove it into a simulated cave. Nice work!

I don’t know what the odds of the rover going into a cave on Mars but I would hope they would code in a reverse route in the event radio contact was lost.

Video

SpaceX Launch Replay

This is the long version.

You may also remember SpaceX is landed the rocket on a ship in April. This time they attempted it again:

Elon Musk “Rocket reentry is a lot faster and hotter than last time, so odds of making it are maybe even, but we should learn a lot either way”.

The attempt was a success! A reusable rocket is reality.

Hydra

hydra_solo

We are beginning to get a bit of compositional data on Pluto’s four small moons.   The moon shown here is Hydra and it appears to be made mostly of water ice.

New Horizons:

The new data – known as infrared spectra – show the unmistakable signature of crystalline water ice: a broad absorption from 1.50 to 1.60 microns and a narrower water-ice spectral feature at 1.65 microns. The Hydra spectrum is similar to that of Pluto’s largest moon, Charon, which is also dominated by crystalline water ice. But Hydra’s water-ice absorption bands are even deeper than Charon’s, suggesting that ice grains on Hydra’s surface are larger or reflect more light at certain angles than the grains on Charon. Hydra is thought to have formed in an icy debris disk produced when water-rich mantles were stripped from the two bodies that collided to form the Pluto-Charon binary some 4 billion years ago. Hydra’s deep water bands and high reflectance imply relatively little contamination by darker material that has accumulated on Charon’s surface over time.

hydracomposite

~click~

Mission scientists are investigating why Hydra’s ice seems to be cleaner than Charon’s. “Perhaps micrometeorite impacts continually refresh the surface of Hydra by blasting off contaminants,” said Simon Porter, a New Horizons science team member from Southwest Research Institute in Boulder, Colorado, “This process would have been ineffective on the much larger Charon, whose much stronger gravity retains any debris created by these impacts.”

The New Horizons science team is looking forward to obtaining similar spectra of Pluto’s other small moons, for comparison to Hydra and Charon.

Credits: NASA/JHUAPL/SwRI

SpaceX Launch Delay

spacexdiscovrlaunch

SpaceX was supposed to launch the JCSat-14 today from Cape Canaveral Florida however due to weather concerns the launch as been moved to Friday 06 May at 05:20 UTC. That particular time is also 01:20 ET which means this will be a night time launch. Lucky us!

The JCSat-14 is a communications satellite to serve the Asia Pacific region.  The satellite will replace an older satellite at 154 degrees East longitude and provide improved capabilities.

The picture above is the SpaceX launch of DSCOVR, it’s one of my favorites.

Credit: SpaceX

Mark Your Calendars

On 09 May 2016 there will be a transit of Mercury.  Will you be able to see it?  Check here.  If it happens you are not able to view it, don’t worry there will be plenty of on-line sources, some of which I will post before hand.

Even if you do live in an area where the the transit is visible DO NOT LOOK AT THE SUN DIRECTLY WITHOUT THE AID OF A SAFE SOLAR FILTER. 

Science@NASA put up a nice video with all the details:

Video