Just heard there will be a total lunar eclipse before dawn on 26 May 2021. Best visible from western North America into the Pacific Ocean. Just 4° altitude at first contact here in Ohio, so not good for us.

Phil S.

Hi All,

For those fortunate to have a large scope I found that the Apollo asteroid 2021 JG1 will approach within ~100,000 km on the 24th through the 26th of May. It's moving at 117"/min. at the fastest The estimated brightness is 16.4 mag.

The orbital elements are attached below, or you can download the latest elements from the MPC.

Phil S.

Hi All,

For those fortunate to have a large scope & live ~30N or further south I found that the Apollo asteroid 2021 GJ3 will approach within <0.02 AU on the 18th & <0.01 AU on the 19th. It's moving at 35.6"/min. The estimated brightness is 16.6 mag.

Phil S.

Hi Greg,

Are we able, and encouraged, to upload observing lists that we create?

If we are, how do we achieve this?

I have the following lists from handbooks to contribute, mostly for Southern Hemisphere observers really.

Deep Sky Companions - Southern Gems, Stephen O'Meara
Deep Sky Companions - The Secret Deep, Stephen O'Meara
Pearls of the Southern Skies - Dieter Willasch & Auke Slotegraaf
Objects in the Heavens - Peter Birren Naoyuki Kurita

I added Nova Cas 2021 to the Current Bright Novae and Supernovae list. It is mag 7.9.

I'm sure some have heard that the large asteroid, 231937 (2001 FO32)
will pass ~5LD or ~2,013,071Km by our blue planet this weekend. The rock
is said to be ~ 1Km in diameter by some sources but others say 0.55±0.11
km. Anyway, it could be as bright as magnitude 11.6 and moving
~3.5'/min, so easily watched motion. Some sources make it a bit
brighter. The down side is that the windows for observing it are
somewhat small.

On the 19th, it remains fairly low, only getting up to about 20° at
08:00UT during dark time from my location at 30°N.

It's worse in the wee hours of the 20th, loosing a few degrees of
altitude when no moon interference.

The 21st is even worse as it is only up in daylight:-(unless you can
snag it between 5 & 6am CDT!  It should be up 18° at 6am moving 190"/min
near azimuth 150°.

If you wait til 7am, you're well into nautical twilight.

You can use ST4 to generate the ephemeris from your location.

Hello everyone,

The version 4.0j R1 update is now ready. You will be prompted to update when you start SkyTools 4, or you can force the update by clicking the Check For Updates button on the Updates, Registration, and Feedback dialog, accessed via the top level Setup menu.

A lot of work has been done on the Imaging Scheduler and Imaging Database Power Search. I also updated the code that reads filter file data so it is much more forgiving of the data entered, and it offers more useful error messages.

SkyTools 4 Visual users should be aware of a bug found in the Backup/Restore feature. The links to plottable images could be lost when restoring a backup made on another computer. If you have seen this problem, restoring a previous backup will now restore your plottable image links correctly.

There are a lot of minor updates as well. For the list see: https://www.skyhound.com/stupdate4.html

It's Messier Marathon season, so I thought I share how to use SkyTools 4 Visual to plan for one.

One of my laments for the Nightly Planner was that it wasn't well suited to planning a Messier Marathon. The purpose of the Nightly Planner is to select the best objects to view on a given night. It's not meant to get you a bad view of something low on the horizon. For good views, the Messier objects are best observed year round, rather than be forced into a single night. 

I was thinking about this and it is one of the reasons that I added the Observing Plan feature. When we plan a Messier Marathon our goal is to observe every object on the list, no matter how bad the view. In this case,  what we want to do is to observe each object when we have the best chance to see it, and to move through the list efficiently. 

Here are the steps to make your own Messier Marathon plan using SkyTools 4 Visual:

1. Pick a night in the spring when you will be free to attempt it. The best nights for a Marathon can be found on the web, but they often choose only the very best night, yet others may work too. New moon nights work best, but a few days before/after may work too. Note the teal line on the Nightbar preview on the Night selection tool, which indicates the altitude of the moon during the night. The best nights will be when the moon is not above the horizon during the dark part of the night.

2. Select a telescope, location, observer and open the Messier Observing List (usually found in the Default folder).

3. Disable all filters. Sort the list by Difficulty, looking for any marked as undetectable. Any object marked as undetectable will most likely be impossible to observe on this night. For most locations and telescope, it is common for a few objects to be out of reach. The idea it to try for as many as possible. But you can try different nights to see if you can get more of these objects to be detectable. Select one of these undetectable objects and look at the red dashed line on the NightBar. Most objects will be low on the horizon during evening or morning twilight. In general, if in the morning twilight, try nights later in the month. If in evening twilight, try nights earlier in the month.

4. Set the weather to what is typical for this time of year or to match the forecast.

5. Under Generate Observing Plan set the amount of time you will typically need to find an object plus the amount of time you intend to view it. For a marathon, allow a little extra time for finding objects and less time to view them. It is best to be honest, especially with the time to find each object.

6. Enable the check box next to Plan to generate your plan.

7. I recommend right-clicking on the View Time column and selecting "Reset Custom View Times."

You may be a bit disappointing in the result. In addition to those objects that are not detectable, the algorithm may toss some objects in order to fit them all into the time allotted. A dark site and a larger telescope will naturally allow you to see more objects.

To see which objects are being skipped, right-click on the check mark column. Select Clear All, and then Check Displayed. Remove the check next to Plan. The objects that were not included in the plan will not have check marks next to them.

Hi All,

My searches of the DBPS for close approaching MPs uncovered a fast mover for next week: 2021 DW1 an Apollo class object. On 3 mar 2021 it's predicted to be 14.7 mag and moving at 106"/min. Here's the OI for 3 Mar:[attachment=1618]

Kenneth, what's your limiting magnitude? Will you be able to observe this one if the weather cooperates? The moon shouldn't interfere. It would be cool if someone's able to observe it.

Phil S.

We will get a near Earth pass of a large rock from space at the end of the month. 1999 RM45 will pass just under 8LD out, so not really super close. But being between 350-780 meters in size with a high albedo might make it worth a look. Possibly 12th magnitude. There are two windows for observing when the moon is below the horizon and the rock is up in the south and moving along at a good clip (42-72 arc seconds per minute) from my backyard. It will be moving along faster later on the evening of March 1, but getting lower and dimmer.

2/28 20:00cst (3/1 02:00UT) Moon 72° away and down 1.4°  or  3/1 20:00cst (3/2 02:00UT) Moon 107° away and down 15°

If you run the ephemeris just prior to observation in ST4, you should be able to get a detailed IA plot.

Kenneth Drake