Search found 5849 matches

by brian livesey
Mon Nov 29, 2021 5:38 pm
Forum: Observing
Topic: Omicron-2 Eridani A or Keid
Replies: 2
Views: 40

Omicron-2 Eridani A or Keid

This star, also known as Keid, is the primary in an interesting triple system, comprising 40 Eridani B, a white dwarf, and 40 Eridani C, a red dwarf. Keid at 4th magnitude is an orange K-type star. The two dwarfs orbit the primary in 8,000 years. The K-type stars are regarded as possibly the best fo...
by brian livesey
Fri Nov 26, 2021 1:29 pm
Forum: Observing
Topic: ISS Pass through a Dob
Replies: 14
Views: 108

Re: ISS Pass through a Dob

Regarding the ISS through 10X50 bins, the Station would appear to be 25 miles away when directly overhead. Obviously, it’s the solar panels that dominate in the binocular view.
by brian livesey
Thu Nov 25, 2021 8:38 pm
Forum: Visual Satellite Observing
Topic: Solar Orbiter space debris risk
Replies: 0
Views: 32

Solar Orbiter space debris risk

The European Space Agency’s Solar Orbiter, launched on February 10th last year, is now approaching the Earth for a gravity slowdown. The spacecraft will whizz past Earth in the next two days, when it’s minimum altitude will be a little higher than the Space Station. A major concern for mission contr...
by brian livesey
Thu Nov 25, 2021 8:07 pm
Forum: Observing
Topic: ISS Pass through a Dob
Replies: 14
Views: 108

Re: ISS Pass through a Dob

Even in 10X50 binoculars the ISS looks irregular in shape.
by brian livesey
Wed Nov 24, 2021 10:22 pm
Forum: Observing
Topic: The Sun Today
Replies: 191
Views: 5356

Re: The Sun Today

A surprising point about dark sunspots is that water molecules are present in them, in the form of steam. The discovery was made by researchers in 1997, combining spectroscopy with other techniques.
by brian livesey
Tue Nov 23, 2021 3:06 pm
Forum: Space exploration
Topic: DART mission to asteroid Dimorphos
Replies: 0
Views: 31

DART mission to asteroid Dimorphos

Tomorrow should see the launch of the asteroid impactor, DART, to attempt to deflect Didymos’s moonlet asteroid, Dimorphos. The craft should arrive at the binary asteroid in September, 2022. DART carries an Italian cubesat that will position itself to monitor the impact, including imaging the result...
by brian livesey
Tue Nov 23, 2021 2:08 pm
Forum: Astrophysics
Topic: A star in a spin
Replies: 0
Views: 36

A star in a spin

A white dwarf has been discovered that has a rotational spin of 25 seconds. This makes the star the fastest of its type so far discovered. The high rotational spin is due to what astrophysicists call a magnetic propellor system, a phenomenon that’s extremely rare. The white dwarf is sloughing off ma...
by brian livesey
Sun Nov 21, 2021 9:51 pm
Forum: Observing
Topic: The Sun Today
Replies: 191
Views: 5356

Re: The Sun Today

Have you seen the live Gong H-a images of the Sun? They correspond more to the details we see with our modest equipment. I find the SOHO and SDO images overpowering with detail and grainy.
by brian livesey
Sun Nov 21, 2021 12:34 pm
Forum: Visual Satellite Observing
Topic: Astronauts and space debris
Replies: 7
Views: 111

Re: Astronauts and space debris

Possibly the chance of being hit by a meteorite is the same or higher than being hit by space junk.
Some years ago, there was a report of highly toxic spent booster fuel leaking out in the Altai region, where boosters frequently fell/fall.
by brian livesey
Sun Nov 21, 2021 12:25 pm
Forum: Observing
Topic: The Sun Today
Replies: 191
Views: 5356

Re: The Sun Today

Some nice proms and a very distinct filament ( like a reversed question mark ) today, through double-stacked PST.
by brian livesey
Sat Nov 20, 2021 3:02 pm
Forum: Visual Satellite Observing
Topic: Astronauts and space debris
Replies: 7
Views: 111

Re: Astronauts and space debris

What are the chances of being hit on the head by space junk? Surely, it doesn’t all burn up.
by brian livesey
Fri Nov 19, 2021 7:23 pm
Forum: Telescopes and instruments
Topic: Large dobsonians
Replies: 30
Views: 305

Re: Large dobsonians

Then you can boldly go where no-one has gone before ... .
by brian livesey
Fri Nov 19, 2021 7:20 am
Forum: Telescopes and instruments
Topic: Large dobsonians
Replies: 30
Views: 305

Re: Large dobsonians

Regarding ‘scope portability, some observers get round the problem by using wheels thence jacks.
by brian livesey
Thu Nov 18, 2021 10:21 pm
Forum: Telescopes and instruments
Topic: Large dobsonians
Replies: 30
Views: 305

Re: Large dobsonians

I had fun with a Prinz 60mm/f.11 refractor. While some were straining with various apertures to see their first white dwarf, the Pup, I was able to see the much easier white dwarf, 40 Eridani B. It was faint in the small refractor, but visible and not overpowered by the orange primary. The mass-prod...
by brian livesey
Thu Nov 18, 2021 7:23 am
Forum: Observing
Topic: Moon @ midnight
Replies: 6
Views: 81

Re: Moon @ midnight

Where’s the bat?